Re: 7x Lathe Transmission Gear Specs?
I stand corrected. Module = PCD (Metric) / #
teeth? Managed to
dig out my old broken plastic gears (never throw anything away) and? measured PDM (Pitch Circle Diameter). of both 21 tooth = 45.5 mm dia Module 2.2? 29 tooth 63 mm dia. module
2.17 Possibly both rounded off to Module 2 ? Cutters normally sold in sets of 8 for MOD ranges of ?0.3 to 8 ?to cut from 12 teeth to rack. Thanks John L
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From: drmico60 To: 7x12minilathe@... Sent:
Thursday, December 6, 2012 3:02 PM Subject: [7x12minilathe] Re: 7x Lathe Transmission Gear Specs?
?
Hi John, Andy and others,
I have rechecked my measurements and still come up with Mod 2.2 for the spindle gears. John L's machine is a Real Bull from Amadeal whereas mine is a Sieg version of the minilathe. Is this yet another diifference between the two machines?
What is the origin of the OP's machine?
Mike
--- In 7x12minilathe@..., John Lindo wrote:
>
> Ian
> Andy is correct ??1.5 module.
> I went through the heartache of machining new Hi/Low gears out of brass.All the gears were to be fly cut??
> off??separate??arbors for each pair and brazing together after finish machining.
> This gear cutting project was due to braking one set of plastic gears while turning an??intermittent??cut at a 100 mm diameter.
> I bought another plastic set and decided to make my own.Out of brass.Silly mistake.
> After making 3 special high speed steel fly cutter bits and a boring bar holder to suit the small and large gears (although all 4 gears are 1.5 module)??
> and applied the correct??relief??angles etc.even used slitting saws to cut between teeth to the various root??diameters to help in metal removal.
> the chatter and banging (although feeding in several passes) seemed to be beating my Weiss mill (the Rolls of the Chinese mills) to pieces.I gave up.
> I still have the cutters if you want them.just send me a PM of your address.
> Also check out out of Hong Kong?? they have good offers.
> It's possibly better to buy the off the shelf steel gears and save your tooling and machines for other projects.
> Again,my Real Bull lathe runs fine with steel gears,but noisy,I was told that the noise will reduce in time,I am still waiting.
> I??regularly??apply lithium (white) grease through my cut out hatch.see link.and it does??quieten??it down.
>
>
> possibly the new brushless High torque lathes have not this problem gear problem.
> Who would of thought we could travel around the world after the Wright brothers barely got off the ground.
> Anyway.
> Also I drop oil directly onto the H/L shift mechanism through the??inspection??hatch.,note from the photos the other lube tube is oiling the plumber block of the feed screw.
> Again no need to remove the back cover.The plastic tube is attached to a nipple on top of the bearing block.
> Using an inspection cover you can also do regular greasing of the tapered roller bearings without having to dismantle the spindle.
> Regards
> John L
> Spain.
>
>
>
>
>
> >________________________________
> > From: Andy Franks
> >To: 7x12minilathe@...
> >Sent: Thursday, December 6, 2012 10:33 AM
> >Subject: RE: [7x12minilathe] Re: 7x Lathe Transmission Gear Specs?
> >
> >
> >??
> >Ian, I believe the gears inside the headstock are Mod 1.5.
> >??
> >You can check this by measuring the outside diameter of one of them in millimetres; preferably one with an even number of teeth. If that measurement is approximately equal to (N + 2) x 1.5 where N is the number of teeth, then they are Mod 1.5.
> >??
> >If I'm wrong and??they are a different Module, use the formula Mod = OD/(N + 2). The gears??are made in China, so don't expect it to work out exactly.
> >??
> >In terms of diametral pitch, Mod 1.5 is just under 17DP, so if you prefer to work in DP, 16 DP would work OK. Actually, these gears only have to mesh with each other so don't have to be to any particular standard, as??long as they are about the right overall??size.
> >??
> >Will it be difficult to cut the smaller gear without the cutter hitting the larger one to which it is attached?
> >??
> >Metal headstock gears are available from LMS. They are probably noisier than the plastic ones.
> >??
> >Andy
> >??
> >
> >
> >________________________________
> > To: 7x12minilathe@...
> >From: iannovak19@...
> >Date: Thu, 6 Dec 2012 06:31:07 +0000
> >Subject: [7x12minilathe] Re: 7x Lathe Transmission Gear Specs?
> >
> >??
> >Thank you for your reply. I am not so worried about the specs of the gears that are right behind the cover. I am looking for specs (pressure angle, diameter, spacing between gears, pitch diameter etc.) for the Hi-Low gears inside the cast spindle head stock.
> >
> >These gears are the most important for the lathe, and the most likely to break compared the the carriage travel speed adjustment gears.
> >
> >If they turn out to be straightforward to make with the help of the experienced instructors, it could be a valuable learning experience and a economic decision.
> >
> >Thank you,
> >
> >Ian
> >
> >--- In 7x12minilathe@..., SirJohnOfYork wrote:
> >>
> >> Metric. Module 1. Center hole is 12mm and on most lathes the keyway is
> >> 3mm (there were some 7x mini-lathes with 4mm
> keyways, check yours if in
> >> doubt.) Thickness is 8mm, but I made some using 5/16" thick plate that I
> >> happened to have handy and they work well.
> >>
> >> You can look at LMS to see the replacement gear sets here
> >> <> for the plastic and here
> >> <> for the steel sets, which list all of the
> >> factory gear sizes minus the two 80 tooth gears which are sold
> >> separately, here <> (plastic) and here
> >> <> (steel).
> >>
> >> Useful sizes not included on the older lathes are 21 and 32 tooth
> >> gears, with the 21 gear
> being most helpful for doing closer
> >> approximations of metric threads with a 16tpi leadscrew (or I believe
> >> inch threads with a metric leadscrew, not sure where you are located or
> >> whether you have a U.S inch or metric leadscrew machine.).
> >>
> >> LMS's Change Gear Page
> >> <> is real handy
> >> for finding workable gear combos for threads not listed on the machine
> >> labels or instructions, and for seeing how the 21 tooth gear can make
> >> for more accurate approximations and such. To see the A, B, C & D gears
> >> illustrated on that page, you need to first enter in a desired thread
> >> and click Calculate, then scroll down to see the pictures. There is a
> >> spacer that is normally behind the D gear than can be swapped to
> in
> >> front of it for those gear combos where an "any" gear is specified, so D
> >> will mesh directly with B (instead of with C as per normal).
> >>
> >> Cheers,
> >> John Z.
> >> York, Pa. USA
> >>
> >> On 12/5/2012 10:40 PM, Ian wrote:
> >> >
> >> > Hello. I have the resources to make my own metal gears in my machine
> >> > shop at school. I would like to be able to make my own set of
> >> > replacement Metal Gears for my 7x Mini lathe.
> >> >
> >> > I am looking for help in finding information about the dimensions and
> >> > specifications of the gears located in the head stock.
> >> >
> >> > Thank you,
> >> >
> >> > Ian
> >> >
> >>
> >
> >
> >
> >
> >
> >
>
|
Re: Threading for the first time
Ralph,
I used your Version 2, 1A style, more or less. Thank you much for sharing
your plans, I¡¯ve either built several or at least used some of the ideas. Great
job!!
?
???????????????????????????????????????????????????????????????????
<>
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Sent: Thursday, December 06, 2012 10:42 AM
Subject: [7x12minilathe] Re: Threading for the first
time
?
?
You can find 3 different sets of Hand Crank Plans here:
HTH
|
Re: Threading for the first time
On 12/06/2012 07:20 AM, andyf1108 wrote: It might be an idea to make it as a wheel rather than a crank, Charlie.
I have a crank, and unplug the lathe before using it, as a reminder to remove the crank before starting the motor later on. If I forget, the crank tries to whack me as the motor starts, at the same time as the lathe tries to turn upside down due to the imbalance. A wheel wouldn't hit me, and would be better balanced.
Andy
I made mine a wheel with removable crank, never considered only making one or the other. For anyone who hasn't seen it: Made almost entirely on the lathe. Saw cuts with a 4x6 bandsaw and the grub screw flat on a mill. -- Jerry Durand, Durand Interstellar, Inc. www.interstellar.com tel: +1 408 356-3886, USA toll free: 1 866 356-3886 Skype: jerrydurand
|
Re: Threading for the first time
Gadgetbuilder has a nice wheel for turning the lathe be hand, see www.gadgetbuilder.com. Mike
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--- In 7x12minilathe@..., "andyf1108" <andyf.1108@...> wrote: It might be an idea to make it as a wheel rather than a crank, Charlie.
I have a crank, and unplug the lathe before using it, as a reminder to remove the crank before starting the motor later on. If I forget, the crank tries to whack me as the motor starts, at the same time as the lathe tries to turn upside down due to the imbalance. A wheel wouldn't hit me, and would be better balanced.
Andy
--- In 7x12minilathe@..., "CLevinski" <clevinski@> wrote:
OK, looks like I need to make a hand-crank for the mini-lathe...
Thanks to all for their suggestions and comments!
Charlie
--- In 7x12minilathe@..., "CLevinski" <clevinski@> wrote:
Hi, All,
I'm going to try single-point threading for the first time. I've read up on the procedure, and I figure the best way is to just jump in and give it a try. I'll initially make a 3/8-24 thread, only because it's big enough for me to really see the progress as it develops. But what I would really like to make for use after that is a 5 mm thread. These are, I believe, a 0.8 mm pitch. My goal is to make some thumbscrews to hold the gear cover on my lathe without having to use a hex key to get it off. My question is whether this is too fine a thread for me to do as a beginner? Are there any special tricks?
I guess it really doesn't matter; if I screw it up (pun intended), I'll just try it again.
Thanks, Charlie
|
Re: Threading for the first time
You can find 3 different sets of Hand Crank Plans here:
HTH
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Show quoted text
--- In 7x12minilathe@..., "CLevinski" <clevinski@...> wrote: OK, looks like I need to make a hand-crank for the mini-lathe...
Thanks to all for their suggestions and comments!
Charlie
--- In 7x12minilathe@..., "CLevinski" <clevinski@> wrote:
Hi, All,
I'm going to try single-point threading for the first time. I've read up on the procedure, and I figure the best way is to just jump in and give it a try. I'll initially make a 3/8-24 thread, only because it's big enough for me to really see the progress as it develops. But what I would really like to make for use after that is a 5 mm thread. These are, I believe, a 0.8 mm pitch. My goal is to make some thumbscrews to hold the gear cover on my lathe without having to use a hex key to get it off. My question is whether this is too fine a thread for me to do as a beginner? Are there any special tricks?
I guess it really doesn't matter; if I screw it up (pun intended), I'll just try it again.
Thanks, Charlie
|
Re: Threading for the first time
It might be an idea to make it as a wheel rather than a crank, Charlie.
I have a crank, and unplug the lathe before using it, as a reminder to remove the crank before starting the motor later on. If I forget, the crank tries to whack me as the motor starts, at the same time as the lathe tries to turn upside down due to the imbalance. A wheel wouldn't hit me, and would be better balanced.
Andy
toggle quoted message
Show quoted text
--- In 7x12minilathe@..., "CLevinski" <clevinski@...> wrote: OK, looks like I need to make a hand-crank for the mini-lathe...
Thanks to all for their suggestions and comments!
Charlie
--- In 7x12minilathe@..., "CLevinski" <clevinski@> wrote:
Hi, All,
I'm going to try single-point threading for the first time. I've read up on the procedure, and I figure the best way is to just jump in and give it a try. I'll initially make a 3/8-24 thread, only because it's big enough for me to really see the progress as it develops. But what I would really like to make for use after that is a 5 mm thread. These are, I believe, a 0.8 mm pitch. My goal is to make some thumbscrews to hold the gear cover on my lathe without having to use a hex key to get it off. My question is whether this is too fine a thread for me to do as a beginner? Are there any special tricks?
I guess it really doesn't matter; if I screw it up (pun intended), I'll just try it again.
Thanks, Charlie
|
Re: Threading for the first time
I made 2, for 2 different 7X lathes, it was very easy. Used a length of
1/2¡± water pipe for the main part, turned down the one end for a couple of
inches or so to be maybe .002¡± smaller than the headstock bore. Split it with a
hacksaw; a long 1/4¡± bolt draws a tapered plug into the end to expand and lock
the thing into place. The crank is made from 1/4¡± flat stock, the handle is a
piece of 3/4¡± aluminum rod, and a long shoulder bolt serves as the crankpin.
There¡¯s plans someplace or another that I followed. I¡¯m lucky enough to have all
of the stuff ¡®in stock¡¯ except for the shoulder bolt, but one could use a
regular bolt and a sleeve instead.
?
????????????????????????????????????????????????????????????????????????????
<>
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Show quoted text
Sent: Wednesday, December 05, 2012 10:06 PM
Subject: [7x12minilathe] Re: Threading for the first
time
?
?
OK, looks like I need to make a hand-crank for the
mini-lathe...
Thanks to all for their suggestions and
comments!
Charlie
--- In mailto:7x12minilathe%40yahoogroups.com,
"CLevinski" wrote: > > Hi, All, >
> I'm going to try single-point threading for the first time. I've read
up on the procedure, and I figure the best way is to just jump in and give it a
try. I'll initially make a 3/8-24 thread, only because it's big enough for me to
really see the progress as it develops. But what I would really like to make for
use after that is a 5 mm thread. These are, I believe, a 0.8 mm pitch. My goal
is to make some thumbscrews to hold the gear cover on my lathe without having to
use a hex key to get it off. My question is whether this is too fine a thread
for me to do as a beginner? Are there any special tricks? > > I
guess it really doesn't matter; if I screw it up (pun intended), I'll just try
it again. > > Thanks, > Charlie >
|
Re: 7x Lathe Transmission Gear Specs?
Hi John, Andy and others, I have rechecked my measurements and still come up with Mod 2.2 for the spindle gears. John L's machine is a Real Bull from Amadeal whereas mine is a Sieg version of the minilathe. Is this yet another diifference between the two machines? What is the origin of the OP's machine? Mike
toggle quoted message
Show quoted text
--- In 7x12minilathe@..., John Lindo <bechetboat@...> wrote: Ian Andy is correct ??1.5 module. I went through the heartache of machining new Hi/Low gears out of brass.All the gears were to be fly cut?? off??separate??arbors for each pair and brazing together after finish machining. This gear cutting project was due to braking one set of plastic gears while turning an??intermittent??cut at a 100 mm diameter. I bought another plastic set and decided to make my own.Out of brass.Silly mistake. After making 3 special high speed steel fly cutter bits and a boring bar holder to suit the small and large gears (although all 4 gears are 1.5 module)?? and applied the correct??relief??angles etc.even used slitting saws to cut between teeth to the various root??diameters to help in metal removal. the chatter and banging (although feeding in several passes) seemed to be beating my Weiss mill (the Rolls of the Chinese mills) to pieces.I gave up. I still have the cutters if you want them.just send me a PM of your address. Also check out out of Hong Kong?? they have good offers. It's possibly better to buy the off the shelf steel gears and save your tooling and machines for other projects. Again,my Real Bull lathe runs fine with steel gears,but noisy,I was told that the noise will reduce in time,I am still waiting. I??regularly??apply lithium (white) grease through my cut out hatch.see link.and it does??quieten??it down.
possibly the new brushless High torque lathes have not this problem gear problem. Who would of thought we could travel around the world after the Wright brothers barely got off the ground. Anyway. Also I drop oil directly onto the H/L shift mechanism through the??inspection??hatch.,note from the photos the other lube tube is oiling the plumber block of the feed screw. Again no need to remove the back cover.The plastic tube is attached to a nipple on top of the bearing block. Using an inspection cover you can also do regular greasing of the tapered roller bearings without having to dismantle the spindle. Regards John L Spain.
________________________________ From: Andy Franks <andyf.1108@...> To: 7x12minilathe@... Sent: Thursday, December 6, 2012 10:33 AM Subject: RE: [7x12minilathe] Re: 7x Lathe Transmission Gear Specs?
?? Ian, I believe the gears inside the headstock are Mod 1.5. ?? You can check this by measuring the outside diameter of one of them in millimetres; preferably one with an even number of teeth. If that measurement is approximately equal to (N + 2) x 1.5 where N is the number of teeth, then they are Mod 1.5. ?? If I'm wrong and??they are a different Module, use the formula Mod = OD/(N + 2). The gears??are made in China, so don't expect it to work out exactly. ?? In terms of diametral pitch, Mod 1.5 is just under 17DP, so if you prefer to work in DP, 16 DP would work OK. Actually, these gears only have to mesh with each other so don't have to be to any particular standard, as??long as they are about the right overall??size. ?? Will it be difficult to cut the smaller gear without the cutter hitting the larger one to which it is attached? ?? Metal headstock gears are available from LMS. They are probably noisier than the plastic ones. ?? Andy ??
________________________________ To: 7x12minilathe@... From: iannovak19@... Date: Thu, 6 Dec 2012 06:31:07 +0000 Subject: [7x12minilathe] Re: 7x Lathe Transmission Gear Specs?
?? Thank you for your reply. I am not so worried about the specs of the gears that are right behind the cover. I am looking for specs (pressure angle, diameter, spacing between gears, pitch diameter etc.) for the Hi-Low gears inside the cast spindle head stock.
These gears are the most important for the lathe, and the most likely to break compared the the carriage travel speed adjustment gears.
If they turn out to be straightforward to make with the help of the experienced instructors, it could be a valuable learning experience and a economic decision.
Thank you,
Ian
--- In 7x12minilathe@..., SirJohnOfYork <steelchipper@> wrote:
Metric. Module 1. Center hole is 12mm and on most lathes the keyway is 3mm (there were some 7x mini-lathes with 4mm
keyways, check yours if in
doubt.) Thickness is 8mm, but I made some using 5/16" thick plate that I happened to have handy and they work well.
You can look at LMS to see the replacement gear sets here <> for the plastic and here <> for the steel sets, which list all of the factory gear sizes minus the two 80 tooth gears which are sold separately, here <> (plastic) and here <> (steel).
Useful sizes not included on the older lathes are 21 and 32 tooth gears, with the 21 gear being most helpful for doing closer
approximations of metric threads with a 16tpi leadscrew (or I believe inch threads with a metric leadscrew, not sure where you are located or whether you have a U.S inch or metric leadscrew machine.).
LMS's Change Gear Page <> is real handy for finding workable gear combos for threads not listed on the machine labels or instructions, and for seeing how the 21 tooth gear can make for more accurate approximations and such. To see the A, B, C & D gears illustrated on that page, you need to first enter in a desired thread and click Calculate, then scroll down to see the pictures. There is a spacer that is normally behind the D gear than can be swapped to in
front of it for those gear combos where an "any" gear is specified, so D will mesh directly with B (instead of with C as per normal).
Cheers, John Z. York, Pa. USA
On 12/5/2012 10:40 PM, Ian wrote:
Hello. I have the resources to make my own metal gears in my machine shop at school. I would like to be able to make my own set of replacement Metal Gears for my 7x Mini lathe.
I am looking for help in finding information about the dimensions and specifications of the gears located in the head stock.
Thank you,
Ian
|
Re: 7x Lathe Transmission Gear Specs?
I do have a set of these:
Metal Transmission Gear Kit, Mini Lathe & 3MT Mini Mill Don't use them... anyone needs them let me know...free to good home.
They appear to be a single piece....
WAM wrote:
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Uh... yes - sorry 'bout that..
andyf1108 wrote:
That's certainly true for the changewheels, Wam, but the query was about the hi/lo speed change gears inside the headstock, which I think are to a different module. Andy
--- In 7x12minilathe@..., WAM <ajawam2@...> wrote:
From this site:
The specifications for the gears used on the Mini-lathe are: module 1, 20??? pressure angle, 8mm face width, and a 12mm bore with a 3mm wide by 1.4mm deep keyway. Any gear that meets these specifications can be used on the lathe.
Andy Franks wrote:
Ian, I believe the gears inside the headstock are Mod 1.5. You can check this by measuring the outside diameter of one of them in millimetres; preferably one with an even number of teeth. If that measurement is approximately equal to (N + 2) x 1.5 where N is the number of teeth, then they are Mod 1.5. If I'm wrong and they are a different Module, use the formula Mod = OD/(N + 2). The gears are made in China, so don't expect it to work out exactly.
In terms of diametral pitch, Mod 1.5 is just under 17DP, so if you prefer to work in DP, 16 DP would work OK. Actually, these gears only have to mesh with each other so don't have to be to any particular standard, as long as they are about the right overall size.
Will it be difficult to cut the smaller gear without the cutter hitting the larger one to which it is attached? Metal headstock gears are available from LMS. They are probably noisier than the plastic ones.
Andy
To: 7x12minilathe@... From: iannovak19@... Date: Thu, 6 Dec 2012 06:31:07 +0000 Subject: [7x12minilathe] Re: 7x Lathe Transmission Gear Specs?
Thank you for your reply. I am not so worried about the specs of the gears that are right behind the cover. I am looking for specs (pressure angle, diameter, spacing between gears, pitch diameter etc.) for the Hi-Low gears inside the cast spindle head stock.
These gears are the most important for the lathe, and the most likely to break compared the the carriage travel speed adjustment gears.
If they turn out to be straightforward to make with the help of the experienced instructors, it could be a valuable learning experience and a economic decision.
Thank you,
Ian
--- In 7x12minilathe@..., SirJohnOfYork <steelchipper@> wrote:
Metric. Module 1. Center hole is 12mm and on most lathes the keyway is 3mm (there were some 7x mini-lathes with 4mm keyways, check yours if in doubt.) Thickness is 8mm, but I made some using 5/16" thick plate that I happened to have handy and they work well.
You can look at LMS to see the replacement gear sets here <> for the plastic and here <> for the steel sets, which list all of the factory gear sizes minus the two 80 tooth gears which are sold separately, here <> (plastic) and here <> (steel).
Useful sizes not included on the older lathes are 21 and 32 tooth gears, with the 21 gear being most helpful for doing closer approximations of metric threads with a 16tpi leadscrew (or I believe inch threads with a metric leadscrew, not sure where you are located or whether you have a U.S inch or metric leadscrew machine.).
LMS's Change Gear Page <> is real handy for finding workable gear combos for threads not listed on the machine labels or instructions, and for seeing how the 21 tooth gear can make for more accurate approximations and such. To see the A, B, C & D gears illustrated on that page, you need to first enter in a desired thread and click Calculate, then scroll down to see the pictures. There is a spacer that is normally behind the D gear than can be swapped to in front of it for those gear combos where an "any" gear is specified, so D will mesh directly with B (instead of with C as per normal).
Cheers, John Z. York, Pa. USA
On 12/5/2012 10:40 PM, Ian wrote:
Hello. I have the resources to make my own metal gears in my machine shop at school. I would like to be able to make my own set of replacement Metal Gears for my 7x Mini lathe.
I am looking for help in finding information about the dimensions and specifications of the gears located in the head stock.
Thank you,
Ian
------------------------------------
Yahoo! Groups Links
|
Re: 7x Lathe Transmission Gear Specs?
Uh... yes - sorry 'bout that..
andyf1108 wrote:
toggle quoted message
Show quoted text
That's certainly true for the changewheels, Wam, but the query was about the hi/lo speed change gears inside the headstock, which I think are to a different module.
Andy
--- In 7x12minilathe@..., WAM wrote:
From this site:
The specifications for the gears used on the Mini-lathe are: module 1,
20¡ã pressure angle, 8mm face width, and a 12mm bore with a 3mm wide by
1.4mm deep keyway. Any gear that meets these specifications can be used
on the lathe.
Andy Franks wrote:
Ian, I believe the gears inside the headstock are Mod 1.5.
You can check this by measuring the outside diameter of one of them in millimetres; preferably one with an even number of teeth. If that measurement is approximately equal to (N + 2) x 1.5 where N is the number of teeth, then they are Mod 1.5.
If I'm wrong and they are a different Module, use the formula Mod = OD/(N + 2). The gears are made in China, so don't expect it to work out exactly.
In terms of diametral pitch, Mod 1.5 is just under 17DP, so if you prefer to work in DP, 16 DP would work OK. Actually, these gears only have to mesh with each other so don't have to be to any particular standard, as long as they are about the right overall size.
Will it be difficult to cut the smaller gear without the cutter hitting the larger one to which it is attached?
Metal headstock gears are available from LMS. They are probably noisier than the plastic ones.
Andy
To: 7x12minilathe@...
From: iannovak19@...
Date: Thu, 6 Dec 2012 06:31:07 +0000
Subject: [7x12minilathe] Re: 7x Lathe Transmission Gear Specs?
Thank you for your reply. I am not so worried about the specs of the gears that are right behind the cover. I am looking for specs (pressure angle, diameter, spacing between gears, pitch diameter etc.) for the Hi-Low gears inside the cast spindle head stock.
These gears are the most important for the lathe, and the most likely to break compared the the carriage travel speed adjustment gears.
If they turn out to be straightforward to make with the help of the experienced instructors, it could be a valuable learning experience and a economic decision.
Thank you,
Ian
--- In 7x12minilathe@..., SirJohnOfYork wrote:
Metric. Module 1. Center hole is 12mm and on most lathes the keyway is
3mm (there were some 7x mini-lathes with 4mm keyways, check yours if in
doubt.) Thickness is 8mm, but I made some using 5/16" thick plate that I
happened to have handy and they work well.
You can look at LMS to see the replacement gear sets here
for the plastic and here
for the steel sets, which list all of the
factory gear sizes minus the two 80 tooth gears which are sold
separately, here (plastic) and here
(steel).
Useful sizes not included on the older lathes are 21 and 32 tooth
gears, with the 21 gear being most helpful for doing closer
approximations of metric threads with a 16tpi leadscrew (or I believe
inch threads with a metric leadscrew, not sure where you are located or
whether you have a U.S inch or metric leadscrew machine.).
LMS's Change Gear Page
is real handy
for finding workable gear combos for threads not listed on the machine
labels or instructions, and for seeing how the 21 tooth gear can make
for more accurate approximations and such. To see the A, B, C & D gears
illustrated on that page, you need to first enter in a desired thread
and click Calculate, then scroll down to see the pictures. There is a
spacer that is normally behind the D gear than can be swapped to in
front of it for those gear combos where an "any" gear is specified, so D
will mesh directly with B (instead of with C as per normal).
Cheers,
John Z.
York, Pa. USA
On 12/5/2012 10:40 PM, Ian wrote:
Hello. I have the resources to make my own metal gears in my machine
shop at school. I would like to be able to make my own set of
replacement Metal Gears for my 7x Mini lathe.
I am looking for help in finding information about the dimensions and
specifications of the gears located in the head stock.
Thank you,
Ian
------------------------------------
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Re: 7x Lathe Transmission Gear Specs?
Ian Andy is correct ?1.5 module. I went through the heartache of machining new Hi/Low gears out of brass.All the gears were to be fly cut? off?separate?arbors for each pair and brazing together after finish machining. This gear cutting project was due to braking one set of plastic gears while turning an?intermittent?cut at a 100 mm diameter. I bought another plastic set and decided to make my own.Out of brass.Silly mistake. After making 3 special high speed steel fly cutter bits and a boring bar holder to suit the small and large gears (although all 4 gears are 1.5 module)? and applied the correct?relief?angles etc.even used slitting saws to cut between teeth to the various root?diameters to help in metal removal. the chatter and banging (although feeding in several passes) seemed to be beating my Weiss mill (the Rolls of the Chinese mills) to pieces.I gave up. I still have the cutters if you want them.just send me a PM of your address. Also check out out of Hong Kong?http://www.ctctools.biz/servlet/StoreFront they have good offers. It's possibly better to buy the off the shelf steel gears and save your tooling and machines for other projects. Again,my Real Bull lathe runs fine with steel gears,but noisy,I was told that the noise will reduce in time,I am still waiting. I?regularly?apply lithium (white) grease through my cut out hatch.see link.and it does?quieten?it
down. https://plus.google.com/photos/112848589944601328801/albums/5757093689495731969
possibly the new brushless High torque lathes have not this problem gear problem. Who would of thought we could travel around the world after the Wright brothers barely got off the ground. Anyway. Also I
drop oil directly onto the H/L shift mechanism through the?inspection?hatch.,note from the photos the other lube tube is oiling the plumber block of the feed screw. Again no need to remove the back cover.The plastic tube is attached to a nipple on top of the bearing block. Using an inspection cover you can also do regular greasing of the tapered roller bearings without having to dismantle the
spindle. Regards John L Spain.
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From: Andy Franks To: 7x12minilathe@... Sent: Thursday, December 6, 2012 10:33 AM Subject:
RE: [7x12minilathe] Re: 7x Lathe Transmission Gear Specs?
?
Ian, I believe the gears inside the headstock are Mod 1.5.
?
You can check this by measuring the outside diameter of one of them in millimetres; preferably one with an even number of teeth. If that measurement is approximately equal to (N + 2) x 1.5 where N is the number of teeth, then they are Mod 1.5.
?
If I'm wrong and?they are a different Module, use the formula Mod = OD/(N + 2). The gears?are made in China, so don't expect it to work out exactly.
?
In terms of diametral pitch, Mod 1.5 is just under 17DP, so if you prefer to work in DP, 16 DP would work OK. Actually, these gears only have to mesh with each other so don't have to be to any particular standard, as?long as they are about the right overall?size.
?
Will it be difficult to cut the smaller gear without the cutter hitting the larger one to which it is attached?
?
Metal headstock gears are available from LMS. They are probably noisier than the plastic ones.
?
Andy ?
To: 7x12minilathe@... From: iannovak19@... Date: Thu, 6 Dec 2012 06:31:07 +0000 Subject: [7x12minilathe] Re: 7x Lathe Transmission Gear Specs? ?
Thank you for your reply. I am not so worried about the specs of the gears that are right behind the cover. I am looking for specs (pressure angle, diameter, spacing between gears, pitch diameter etc.) for the Hi-Low gears inside the cast spindle head stock. These gears are the most important for the lathe, and the most likely to break compared the the carriage travel speed adjustment gears. If they turn out to be straightforward to make with the help of the experienced instructors, it could be a valuable learning experience and a economic decision. Thank you, Ian --- In 7x12minilathe@..., SirJohnOfYork wrote: > > Metric. Module 1. Center hole is 12mm and on most lathes the keyway is > 3mm (there were some 7x mini-lathes with 4mm
keyways, check yours if in > doubt.) Thickness is 8mm, but I made some using 5/16" thick plate that I > happened to have handy and they work well. > > You can look at LMS to see the replacement gear sets here > <> for the plastic and here > <> for the steel sets, which list all of the > factory gear sizes minus the two 80 tooth gears which are sold > separately, here <> (plastic) and here > <> (steel). > > Useful sizes not included on the older lathes are 21 and 32 tooth > gears, with the 21 gear
being most helpful for doing closer > approximations of metric threads with a 16tpi leadscrew (or I believe > inch threads with a metric leadscrew, not sure where you are located or > whether you have a U.S inch or metric leadscrew machine.). > > LMS's Change Gear Page > <> is real handy > for finding workable gear combos for threads not listed on the machine > labels or instructions, and for seeing how the 21 tooth gear can make > for more accurate approximations and such. To see the A, B, C & D gears > illustrated on that page, you need to first enter in a desired thread > and click Calculate, then scroll down to see the pictures. There is a > spacer that is normally behind the D gear than can be swapped to
in > front of it for those gear combos where an "any" gear is specified, so D > will mesh directly with B (instead of with C as per normal). > > Cheers, > John Z. > York, Pa. USA > > On 12/5/2012 10:40 PM, Ian wrote: > > > > Hello. I have the resources to make my own metal gears in my machine > > shop at school. I would like to be able to make my own set of > > replacement Metal Gears for my 7x Mini lathe. > > > > I am looking for help in finding information about the dimensions and > > specifications of the gears located in the head stock. > > > > Thank you, > > > > Ian > > >
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Re: 7x Lathe Transmission Gear Specs?
I have a spare gear set and I have just measured them with the following results:
21/29 gear for the spindle has diameters of 52mm and 68mm this gives a mod of 2.2
The metal 21/29 gear supplied by ArcEurotrade are supplied as three pieces comprising the the two gears and a spacer. I think this is because it is difficult to machine it as one piece because the cutter for the small gear would interfere with the larger gear. Making it in this way has a downside because there is very little metal between the bottom of the gear tooth and the hole for the shaft on the 21 tooth gear, making the gear very weak particularly near the keyway. In fact the gear supplied to me by ArcEuro is cracked at this point and it has never been fitted because of this.(I did not return it to Arc Euro because I did not attempt to fit it until a long time after having purchased it.)
The 21/29 gear has a bore of 30 mm and a 5 mm keyway to fit the spindle. The smaller 12/20 tooth layshaft gear is bored 12 mm and has a 3 mm keyway.
If you are going to make new gears then it does not matter too much what pressure angle and module you use as long as it is the same for the two gears and the dimensions are about right. However, in view of the intrinsic weakness with gears made in three pieces the selection of material for the gear may be critical.
I hope this is helpful.
Mike
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Show quoted text
--- In 7x12minilathe@..., Andy Franks <andyf.1108@...> wrote:
Ian, I believe the gears inside the headstock are Mod 1.5.
You can check this by measuring the outside diameter of one of them in millimetres; preferably one with an even number of teeth. If that measurement is approximately equal to (N + 2) x 1.5 where N is the number of teeth, then they are Mod 1.5.
If I'm wrong and they are a different Module, use the formula Mod = OD/(N + 2). The gears are made in China, so don't expect it to work out exactly.
In terms of diametral pitch, Mod 1.5 is just under 17DP, so if you prefer to work in DP, 16 DP would work OK. Actually, these gears only have to mesh with each other so don't have to be to any particular standard, as long as they are about the right overall size.
Will it be difficult to cut the smaller gear without the cutter hitting the larger one to which it is attached?
Metal headstock gears are available from LMS. They are probably noisier than the plastic ones.
Andy
To: 7x12minilathe@... From: iannovak19@... Date: Thu, 6 Dec 2012 06:31:07 +0000 Subject: [7x12minilathe] Re: 7x Lathe Transmission Gear Specs?
Thank you for your reply. I am not so worried about the specs of the gears that are right behind the cover. I am looking for specs (pressure angle, diameter, spacing between gears, pitch diameter etc.) for the Hi-Low gears inside the cast spindle head stock.
These gears are the most important for the lathe, and the most likely to break compared the the carriage travel speed adjustment gears.
If they turn out to be straightforward to make with the help of the experienced instructors, it could be a valuable learning experience and a economic decision.
Thank you,
Ian
--- In 7x12minilathe@..., SirJohnOfYork <steelchipper@> wrote:
Metric. Module 1. Center hole is 12mm and on most lathes the keyway is 3mm (there were some 7x mini-lathes with 4mm keyways, check yours if in doubt.) Thickness is 8mm, but I made some using 5/16" thick plate that I happened to have handy and they work well.
You can look at LMS to see the replacement gear sets here <> for the plastic and here <> for the steel sets, which list all of the factory gear sizes minus the two 80 tooth gears which are sold separately, here <> (plastic) and here <> (steel).
Useful sizes not included on the older lathes are 21 and 32 tooth gears, with the 21 gear being most helpful for doing closer approximations of metric threads with a 16tpi leadscrew (or I believe inch threads with a metric leadscrew, not sure where you are located or whether you have a U.S inch or metric leadscrew machine.).
LMS's Change Gear Page <> is real handy for finding workable gear combos for threads not listed on the machine labels or instructions, and for seeing how the 21 tooth gear can make for more accurate approximations and such. To see the A, B, C & D gears illustrated on that page, you need to first enter in a desired thread and click Calculate, then scroll down to see the pictures. There is a spacer that is normally behind the D gear than can be swapped to in front of it for those gear combos where an "any" gear is specified, so D will mesh directly with B (instead of with C as per normal).
Cheers, John Z. York, Pa. USA
On 12/5/2012 10:40 PM, Ian wrote:
Hello. I have the resources to make my own metal gears in my machine shop at school. I would like to be able to make my own set of replacement Metal Gears for my 7x Mini lathe.
I am looking for help in finding information about the dimensions and specifications of the gears located in the head stock.
Thank you,
Ian
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Bearing seal for front tapered roller bearing?
I am installing tapered roller bearings in my 7x lathe headstock. In reading various postings on the subject I have noted that some people have used o rings and some have used automotive gasket material to prevent swarf from reaching the unsealed front bearing. I have been considering using a felt wiper gasket under the bearing cover. I welcome input on this topic and look forward to hearing about how you have addressed this issue. Thanks Dick
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Re: 7x Lathe Transmission Gear Specs?
That's certainly true for the changewheels, Wam, but the query was about the hi/lo speed change gears inside the headstock, which I think are to a different module.
Andy
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Show quoted text
--- In 7x12minilathe@..., WAM <ajawam2@...> wrote: From this site:
The specifications for the gears used on the Mini-lathe are: module 1, 20¡ã pressure angle, 8mm face width, and a 12mm bore with a 3mm wide by 1.4mm deep keyway. Any gear that meets these specifications can be used on the lathe.
Andy Franks wrote:
Ian, I believe the gears inside the headstock are Mod 1.5.
You can check this by measuring the outside diameter of one of them in millimetres; preferably one with an even number of teeth. If that measurement is approximately equal to (N + 2) x 1.5 where N is the number of teeth, then they are Mod 1.5.
If I'm wrong and they are a different Module, use the formula Mod = OD/(N + 2). The gears are made in China, so don't expect it to work out exactly.
In terms of diametral pitch, Mod 1.5 is just under 17DP, so if you prefer to work in DP, 16 DP would work OK. Actually, these gears only have to mesh with each other so don't have to be to any particular standard, as long as they are about the right overall size.
Will it be difficult to cut the smaller gear without the cutter hitting the larger one to which it is attached?
Metal headstock gears are available from LMS. They are probably noisier than the plastic ones.
Andy
To: 7x12minilathe@... From: iannovak19@... Date: Thu, 6 Dec 2012 06:31:07 +0000 Subject: [7x12minilathe] Re: 7x Lathe Transmission Gear Specs?
Thank you for your reply. I am not so worried about the specs of the gears that are right behind the cover. I am looking for specs (pressure angle, diameter, spacing between gears, pitch diameter etc.) for the Hi-Low gears inside the cast spindle head stock.
These gears are the most important for the lathe, and the most likely to break compared the the carriage travel speed adjustment gears.
If they turn out to be straightforward to make with the help of the experienced instructors, it could be a valuable learning experience and a economic decision.
Thank you,
Ian
--- In 7x12minilathe@..., SirJohnOfYork <steelchipper@> wrote:
Metric. Module 1. Center hole is 12mm and on most lathes the keyway is 3mm (there were some 7x mini-lathes with 4mm keyways, check yours if in doubt.) Thickness is 8mm, but I made some using 5/16" thick plate that I happened to have handy and they work well.
You can look at LMS to see the replacement gear sets here <> for the plastic and here <> for the steel sets, which list all of the factory gear sizes minus the two 80 tooth gears which are sold separately, here <> (plastic) and here <> (steel).
Useful sizes not included on the older lathes are 21 and 32 tooth gears, with the 21 gear being most helpful for doing closer approximations of metric threads with a 16tpi leadscrew (or I believe inch threads with a metric leadscrew, not sure where you are located or whether you have a U.S inch or metric leadscrew machine.).
LMS's Change Gear Page <> is real handy for finding workable gear combos for threads not listed on the machine labels or instructions, and for seeing how the 21 tooth gear can make for more accurate approximations and such. To see the A, B, C & D gears illustrated on that page, you need to first enter in a desired thread and click Calculate, then scroll down to see the pictures. There is a spacer that is normally behind the D gear than can be swapped to in front of it for those gear combos where an "any" gear is specified, so D will mesh directly with B (instead of with C as per normal).
Cheers, John Z. York, Pa. USA
On 12/5/2012 10:40 PM, Ian wrote:
Hello. I have the resources to make my own metal gears in my machine shop at school. I would like to be able to make my own set of replacement Metal Gears for my 7x Mini lathe.
I am looking for help in finding information about the dimensions and specifications of the gears located in the head stock.
Thank you,
Ian
|
Re: Narrow angle center drill
--- In 7x12minilathe@..., "chucketn" <chunk07@...> wrote: I have a narrow angle center drill I found in my late fathers tools. Only markings are USA and 0-2. Definitly different than the center drills I bought from LMS. What would it be used fore? /guseeing it is about 30 ¡ã.
Chuck
I took a picture of the center drill in question next to the 60¡ã one from my set from LMS. Any ideas as to what it's tued for? Chuck
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Re: 7x Lathe Transmission Gear Specs?
From this site:
The specifications for the gears used on the Mini-lathe are: module 1,
20??? pressure angle, 8mm face width, and a 12mm bore with a 3mm wide by
1.4mm deep keyway. Any gear that meets these specifications can be used
on the lathe.
Andy Franks wrote:
toggle quoted message
Show quoted text
Ian, I believe the gears inside the headstock are Mod 1.5.
You can check this by measuring the outside diameter of one of them in millimetres; preferably one with an even number of teeth. If that measurement is approximately equal to (N + 2) x 1.5 where N is the number of teeth, then they are Mod 1.5.
If I'm wrong and they are a different Module, use the formula Mod = OD/(N + 2). The gears are made in China, so don't expect it to work out exactly.
In terms of diametral pitch, Mod 1.5 is just under 17DP, so if you prefer to work in DP, 16 DP would work OK. Actually, these gears only have to mesh with each other so don't have to be to any particular standard, as long as they are about the right overall size.
Will it be difficult to cut the smaller gear without the cutter hitting the larger one to which it is attached?
Metal headstock gears are available from LMS. They are probably noisier than the plastic ones.
Andy
To: 7x12minilathe@...
From: iannovak19@...
Date: Thu, 6 Dec 2012 06:31:07 +0000
Subject: [7x12minilathe] Re: 7x Lathe Transmission Gear Specs?
Thank you for your reply. I am not so worried about the specs of the gears that are right behind the cover. I am looking for specs (pressure angle, diameter, spacing between gears, pitch diameter etc.) for the Hi-Low gears inside the cast spindle head stock.
These gears are the most important for the lathe, and the most likely to break compared the the carriage travel speed adjustment gears.
If they turn out to be straightforward to make with the help of the experienced instructors, it could be a valuable learning experience and a economic decision.
Thank you,
Ian
--- In 7x12minilathe@..., SirJohnOfYork wrote:
Metric. Module 1. Center hole is 12mm and on most lathes the keyway is
3mm (there were some 7x mini-lathes with 4mm keyways, check yours if in
doubt.) Thickness is 8mm, but I made some using 5/16" thick plate that I
happened to have handy and they work well.
You can look at LMS to see the replacement gear sets here
for the plastic and here
for the steel sets, which list all of the
factory gear sizes minus the two 80 tooth gears which are sold
separately, here (plastic) and here
(steel).
Useful sizes not included on the older lathes are 21 and 32 tooth
gears, with the 21 gear being most helpful for doing closer
approximations of metric threads with a 16tpi leadscrew (or I believe
inch threads with a metric leadscrew, not sure where you are located or
whether you have a U.S inch or metric leadscrew machine.).
LMS's Change Gear Page
is real handy
for finding workable gear combos for threads not listed on the machine
labels or instructions, and for seeing how the 21 tooth gear can make
for more accurate approximations and such. To see the A, B, C & D gears
illustrated on that page, you need to first enter in a desired thread
and click Calculate, then scroll down to see the pictures. There is a
spacer that is normally behind the D gear than can be swapped to in
front of it for those gear combos where an "any" gear is specified, so D
will mesh directly with B (instead of with C as per normal).
Cheers,
John Z.
York, Pa. USA
On 12/5/2012 10:40 PM, Ian wrote:
Hello. I have the resources to make my own metal gears in my machine
shop at school. I would like to be able to make my own set of
replacement Metal Gears for my 7x Mini lathe.
I am looking for help in finding information about the dimensions and
specifications of the gears located in the head stock.
Thank you,
Ian
|
Re: 7x Lathe Transmission Gear Specs?
Ian, I believe the gears inside the headstock are Mod 1.5.
?
You can check this by measuring the outside diameter of one of them in millimetres; preferably one with an even number of teeth. If that measurement is approximately equal to (N + 2) x 1.5 where N is the number of teeth, then they are Mod 1.5.
?
If I'm wrong and?they are a different Module, use the formula Mod = OD/(N + 2). The gears?are made in China, so don't expect it to work out exactly.
?
In terms of diametral pitch, Mod 1.5 is just under 17DP, so if you prefer to work in DP, 16 DP would work OK. Actually, these gears only have to mesh with each other so don't have to be to any particular standard, as?long as they are about the right overall?size.
?
Will it be difficult to cut the smaller gear without the cutter hitting the larger one to which it is attached?
?
Metal headstock gears are available from LMS. They are probably noisier than the plastic ones.
?
Andy ?
To: 7x12minilathe@... From: iannovak19@... Date: Thu, 6 Dec 2012 06:31:07 +0000 Subject: [7x12minilathe] Re: 7x Lathe Transmission Gear Specs? ?
Thank you for your reply. I am not so worried about the specs of the gears that are right behind the cover. I am looking for specs (pressure angle, diameter, spacing between gears, pitch diameter etc.) for the Hi-Low gears inside the cast spindle head stock.
These gears are the most important for the lathe, and the most likely to break compared the the carriage travel speed adjustment gears.
If they turn out to be straightforward to make with the help of the experienced instructors, it could be a valuable learning experience and a economic decision.
Thank you,
Ian
toggle quoted message
Show quoted text
--- In 7x12minilathe@..., SirJohnOfYork wrote: > > Metric. Module 1. Center hole is 12mm and on most lathes the keyway is > 3mm (there were some 7x mini-lathes with 4mm keyways, check yours if in > doubt.) Thickness is 8mm, but I made some using 5/16" thick plate that I > happened to have handy and they work well. > > You can look at LMS to see the replacement gear sets here > <> for the plastic and here > <> for the steel sets, which list all of the > factory gear sizes minus the two 80 tooth gears which are sold > separately, here <> (plastic) and here > <> (steel). > > Useful sizes not included on the older lathes are 21 and 32 tooth > gears, with the 21 gear being most helpful for doing closer > approximations of metric threads with a 16tpi leadscrew (or I believe > inch threads with a metric leadscrew, not sure where you are located or > whether you have a U.S inch or metric leadscrew machine.). > > LMS's Change Gear Page > <> is real handy > for finding workable gear combos for threads not listed on the machine > labels or instructions, and for seeing how the 21 tooth gear can make > for more accurate approximations and such. To see the A, B, C & D gears > illustrated on that page, you need to first enter in a desired thread > and click Calculate, then scroll down to see the pictures. There is a > spacer that is normally behind the D gear than can be swapped to in > front of it for those gear combos where an "any" gear is specified, so D > will mesh directly with B (instead of with C as per normal). > > Cheers, > John Z. > York, Pa. USA > > On 12/5/2012 10:40 PM, Ian wrote: > > > > Hello. I have the resources to make my own metal gears in my machine > > shop at school. I would like to be able to make my own set of > > replacement Metal Gears for my 7x Mini lathe. > > > > I am looking for help in finding information about the dimensions and > > specifications of the gears located in the head stock. > > > > Thank you, > > > > Ian > > >
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Re: What is description for the button head screws used to replace the allen heads on cross and topslide handles?
Hi M6x8 is a normal metric thread with diameter is 6mm there ar 1 mm from top to top and the angle of the thread is 60. 8 is lhe length off the bolt Jorgen
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Show quoted text
--- In 7x12minilathe@..., Richard Brennan <brennan8@...> wrote: What he said! Cap Screw M6-1.0 X 8 (I had just looked it up yesterday...)
-------------------- Richard Brennan - San Leandro CA --------------------
At 04:20 PM 12/5/2012, Chris Wood wrote:
The screw is an M6x8 button head socket cap screw.
Regards,
Chris Wood <>LittleMachineShop.com The premier source of tooling, parts, and accessories for bench top machinists. 396 W. Washington Blvd. #500, Pasadena, CA 91103 (800)981-9663 * Fax (626)797-7934
From: 7x12minilathe@... [mailto:7x12minilathe@...] On Behalf Of Michael Jablonski Sent: Wednesday, December 05, 2012 3:05 PM To: 7x12minilathe@... Subject: RE: [7x12minilathe] What is description for the button head screws used to replace the allen heads on cross and topslide handles?
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Re: 7x Lathe Transmission Gear Specs?
Thank you for your reply. I am not so worried about the specs of the gears that are right behind the cover. I am looking for specs (pressure angle, diameter, spacing between gears, pitch diameter etc.) for the Hi-Low gears inside the cast spindle head stock.
These gears are the most important for the lathe, and the most likely to break compared the the carriage travel speed adjustment gears.
If they turn out to be straightforward to make with the help of the experienced instructors, it could be a valuable learning experience and a economic decision.
Thank you,
Ian
toggle quoted message
Show quoted text
--- In 7x12minilathe@..., SirJohnOfYork <steelchipper@...> wrote: Metric. Module 1. Center hole is 12mm and on most lathes the keyway is 3mm (there were some 7x mini-lathes with 4mm keyways, check yours if in doubt.) Thickness is 8mm, but I made some using 5/16" thick plate that I happened to have handy and they work well.
You can look at LMS to see the replacement gear sets here <> for the plastic and here <> for the steel sets, which list all of the factory gear sizes minus the two 80 tooth gears which are sold separately, here <> (plastic) and here <> (steel).
Useful sizes not included on the older lathes are 21 and 32 tooth gears, with the 21 gear being most helpful for doing closer approximations of metric threads with a 16tpi leadscrew (or I believe inch threads with a metric leadscrew, not sure where you are located or whether you have a U.S inch or metric leadscrew machine.).
LMS's Change Gear Page <> is real handy for finding workable gear combos for threads not listed on the machine labels or instructions, and for seeing how the 21 tooth gear can make for more accurate approximations and such. To see the A, B, C & D gears illustrated on that page, you need to first enter in a desired thread and click Calculate, then scroll down to see the pictures. There is a spacer that is normally behind the D gear than can be swapped to in front of it for those gear combos where an "any" gear is specified, so D will mesh directly with B (instead of with C as per normal).
Cheers, John Z. York, Pa. USA
On 12/5/2012 10:40 PM, Ian wrote:
Hello. I have the resources to make my own metal gears in my machine shop at school. I would like to be able to make my own set of replacement Metal Gears for my 7x Mini lathe.
I am looking for help in finding information about the dimensions and specifications of the gears located in the head stock.
Thank you,
Ian
|
Re: Threading for the first time
My first threads were 1/4 -20 ,then I made 1/2-40. Both turned out well. I could test the 1/4-20 with a standard nut but the 1/2-40 wasn't tested.I could have tried making a nut to fit, I figured I'll leave well enough alone for now.I read a lot, asked questions and then gave it a try.I was happy that the threads looked right . I'm sure you can do it with a bit of practice.As far as tips go, I'm almost as much a rank beginner cutting threads as you are. mike
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From: CLevinski To: 7x12minilathe@... Sent: Wednesday, December 5, 2012 7:57 AM Subject: [7x12minilathe] Threading for the first time
?
Hi, All,
I'm going to try single-point threading for the first time. I've read up on the procedure, and I figure the best way is to just jump in and give it a try. I'll initially make a 3/8-24 thread, only because it's big enough for me to really see the progress as it develops. But what I would really like to make for use after that is a 5 mm thread. These are, I believe, a 0.8 mm pitch. My goal is to make some thumbscrews to hold the gear cover on my lathe without having to use a hex key to get it off. My question is whether this is too fine a thread for me to do as a beginner? Are there any special tricks?
I guess it really doesn't matter; if I screw it up (pun intended), I'll just try it again.
Thanks,
Charlie
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