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Re: Horsepower Resistor

 

--- In 7x12minilathe@..., "Tony Smith" wrote:
watts
of the "official" HP resistors. Tony Smith's 5W suggestion a few posts
back will
most likely work perfectly well. 0.022 ohm, rather than 0.025 ohm, will
before get 4 of those and solder them together. Looking in the case
arranging them in a 2x2 formation might be the go.
I agree , either use a 0.022 or 4 in parallel .
If you look at the schematic, you will see that all curent drawn is going through this resistor, and an opamp are then measuring on the current ..
The only thing that could happen is that the motor draw a bit more before the regulator cutt out.

it would be close to 12 percent more..if they are spot on value.. therefore choose 5% or better ,in tollerance.

to be on the safe side, you could choose a 0.033 .,but if there is room for 4 , maybe 2watt then I would choose this solution with four 0.1 R
alex
Re: Horsepower Resistor

Jerry Durand
 

On 02/04/2013 01:23 AM, andyf1108 wrote:
The originals are plug-in jobs, so you may have to find two bits of brass to stick down the sockets, and solder the resistor(s) between them. The aluminium chassis under KB boards prevents you soldering one on the underside.
or cut the brass bits off the old resistor and solder on the new ones.

--
Jerry Durand, Durand Interstellar, Inc. www.interstellar.com
tel: +1 408 356-3886, USA toll free: 1 866 356-3886
Skype: jerrydurand
Re: Horsepower Resistor

Jerry Durand
 

开云体育

On 02/04/2013 01:03 AM, Clive Burdikin wrote:
The Chinese New Year is 10 February, so you should be alright

Except Friday was the last day before vacation for a lot of them.? Think Christmas vacation...can't find anyone working a week before.?

I just received notification that FedEx has the package in Shanghai.? They updated my delivery to this Friday so I warned my customer this rush job won't be quite as rush as hoped.
-- 
Jerry Durand, Durand Interstellar, Inc.  
tel: +1 408 356-3886, USA toll free: 1 866 356-3886
Skype:  jerrydurand

Re: Digital linear scale for 7x lathe?

 

Someone at projectsinmetal.com is working on a similar project using an arduino board and a tablet for a display. Grizzly sells a couple of different types of scales. One may even work for you out of the box.
Kenny

--- In 7x12minilathe@..., WAM wrote:

There's a 3D model and PDF drawings of my setup at:


A pic:



John Mattis wrote:

I just use a 1 inch travel dial indicator with a removable mount that
attaches to the front of the bed. I also have a adjustable stop that goes
between the carriage and the head stock. Drawings are available if you
E-mail me separate from the group.
John
Re: Digital linear scale for 7x lathe?

 

There's a 3D model and PDF drawings of my setup at:


A pic:



John Mattis wrote:

I just use a 1 inch travel dial indicator with a removable mount that
attaches to the front of the bed. I also have a adjustable stop that goes
between the carriage and the head stock. Drawings are available if you
E-mail me separate from the group.
John
Re: Digital linear scale for 7x lathe?

 

I just use a 1 inch travel dial indicator with a removable mount that attaches to the front of the bed. I also have a adjustable stop that goes between the carriage and the head stock. Drawings are available if you E-mail me separate from the group.
John
Re: Which lube do you use

David Everett
 

Do not use coolant/lube on cast iron or brass/gunmetal. ?Coolant is normally used on steel.

For normal hobby type work, if you must use a coolant/lube then soluble oil is quite adequate when used from an old pump spray bottle that your domestic staff have finished with. ?Alternatively, you can have a small pot and use an old paintbrush to wipe the oil on. ?Others may recommend neat cutting oil - your choice. ?I say 'must use' - normally we don't push our machines hard enough to warrant the use of coolant, except perhaps on the finishing cut, where it can improve the surface finish.

If you are using carbide tools (why?) do not use a coolant unless you are flooding the work. ?To use flood cooling, your machines are best used in an enclosed working space to prevent oil flying all over the place.? If you are using HSS tools, then you may consider using a coolant.? Mist cooling has its adherents. ?Some love it, others say it fogs up the workshop.

When you have finished working, wipe your machines down to the oil prevent staining of the bare metal.

Just re-read your question. ?For aluminium, WD40 is a good lubricant and can prevent build up of chips on the tool cutting edge. ?WD40 in aerosol form is expensive, get a 5 ltr. drum and use the above mentioned spray bottle.?

Dave
The Emerald Isle

From: Ebner Heating Air Conditioning Co.
To: 7x12minilathe@...
Sent: Monday, 4 February 2013, 13:23
Subject: [7x12minilathe] Which lube do you use

?
Excuse me if this question has already been asked but I am curious as to what you recommend to keep cutting tools cool. Do you recommend a pump to flood the tool and material being machined, a mist coolant spray, or the old fashioned chip brush dunked in cutting oil? Most of my work?will be done with aluminum.
?
Also is there any one book that stands out from the rest as far as lathe and mill practices that you might recommend to a newb?
Digital linear scale for 7x lathe?

 

I am strongly considering a Z axis digital linear scale for my 7 x 16 lathe.
I am thinking I might want to mount it onto the rear side of the bed below the saddle gibs. The scale would have a remote reader that I could place anywhere within 48".
Has anyone done this? I like to get as much info and learn of any experiences others may have had when doing this mod.
Thanks
Dick
Which lube do you use

Ebner Heating Air Conditioning Co.
 

开云体育

Excuse me if this question has already been asked but I am curious as to what you recommend to keep cutting tools cool. Do you recommend a pump to flood the tool and material being machined, a mist coolant spray, or the old fashioned chip brush dunked in cutting oil? Most of my work?will be done with aluminum.
?
Also is there any one book that stands out from the rest as far as lathe and mill practices that you might recommend to a newb?
Re: Horsepower Resistor

 

I suggested 10W wirewounds because I simply don't know the ratings in
watts
of the "official" HP resistors. Tony Smith's 5W suggestion a few posts
back will
most likely work perfectly well. 0.022 ohm, rather than 0.025 ohm, will
make
no practical difference.

The originals are plug-in jobs, so you may have to find two bits of brass
to stick
down the sockets, and solder the resistor(s) between them. The aluminium
chassis under KB boards prevents you soldering one on the underside.

Andy

I've had a quick look, and they are 5W resistors (size determines power).
You can unsolder the original; the pins are hollow so just heat them up with
the soldering and pull on the resistor, they'll come out easily enough.

It's occurred to me that 0.022 ohm is rather smaller, and it seems these are
a rather special resistor.

The smallest you'll be able to get without any major effort (i.e. beyond
wandering into a Jaycar store) would be 0.1 ohms, as per here:
. As Andy suggested
before get 4 of those and solder them together. Looking in the case
arranging them in a 2x2 formation might be the go.

Total cost will be $1.60 plus a bit of soldering.

I'm not surprised you can't get them locally, none of the sellers want to
stock spare parts to cater for the 6 of us who own these lathes here in Oz.
We should track down the other 4 and start a club or something.

Tony
Re: Horsepower Resistor

Den Strods
 

Thank you to all for your help.
I think i will try making my own
?"The originals are plug-in jobs, so you may have to find two bits of brass to stick down the sockets, and solder the resistor(s) between them. The aluminium chassis under KB boards prevents you soldering one on the underside."
Cheers
Re: Horsepower Resistor

 

I suggested 10W wirewounds because I simply don't know the ratings in watts of the "official" HP resistors. Tony Smith's 5W suggestion a few posts back will most likely work perfectly well. 0.022 ohm, rather than 0.025 ohm, will make no practical difference.

The originals are plug-in jobs, so you may have to find two bits of brass to stick down the sockets, and solder the resistor(s) between them. The aluminium chassis under KB boards prevents you soldering one on the underside.

Andy

--- In 7x12minilathe@..., "Den" wrote:

Will give it a try.
Thanks

--- In 7x12minilathe@..., "andyf1108" wrote:

I'm reasonably familiar with KB's website, Den, having used it to find UK distributors.

If all else fails, you could make one up yourself. Ceramic cased, 0.1 ohm 10 watt wirewound resistors seem pretty readily available, and four of those in parallel would give you 0.025 ohms. They would handle 40W, which is probably an unecessarily high rating for the job, but there's no harm in that.

Andy

--- In 7x12minilathe@..., Den Strods wrote:

That was quick.
Thanks for your effort, I will ring them in ?the morning.
Cheers
Re: Horsepower Resistor

Den
 

I will give them a try.
Just to be clear this is a Plugin resistor made especially for KB Electronics speed control boards so i dont like my chances of finding one in a OZ store.
Den from Newcastle

--- In 7x12minilathe@..., Andrew wrote:

Try Jaycar or Alltronics. In the eastern suburbs of Melbourne I would
recommened going to Trucotts Electronic World.

Cheers,

Andrew in Melbourne


On 03/02/13 22:39, MERTON B BAKER wrote:

Surely there are radio supply stores in Australia? I know it's vast &
populated mostly around the edges, but I would think that asking around
would turn up a solution.

Mert

-----Original Message-----
From: 7x12minilathe@...

[mailto:7x12minilathe@...
]On Behalf Of Den
Sent: Sunday, February 03, 2013 4:40 AM
To: 7x12minilathe@...
Subject: [7x12minilathe] Horsepower Resistor

I am trying to by a .025 plugin horsepower resistor for a KBCL-240D
board.I
found some on US ebay for $5 but postage to Australia is $26.
Is there some place that sells these with reasonable postage to Australia.
I have probably missed the obvious.
Cheers and thanks for your help.

------------------------------------

Yahoo! Groups Links
Re: Horsepower Resistor

 

开云体育

The Chinese New Year is 10 February, so you should be alright
?

Sent: Sunday, February 03, 2013 7:01 PM
Subject: Re: [7x12minilathe] Horsepower Resistor
?
?

On 02/03/2013 06:49 AM, Mark Schwiebert wrote:

Look for a supplier ,on ebay from china,most offer a free economy shipping.
I read the Chineese Govt is smart enough to allow super cheap shipping ,by putting mail on US bound ships,flights,etc. to allow exports to go out with out a customer worring about excess costs.
You think our Govt.,would do this to try to get US made goods out ,and increase jobs,& commerce.
The china made components are so cheap,I usuall buy 10.00 worth,and have spares,as I have found brand new ones that did not work either.


Our company buys items from China fairly often and the shipping is always amazing.? For a current customer project I need some high current solid state relays.? In the USA a 40 Amp relay is around $47 each plus shipping.? I ordered ten of them from the factory* and the total WITH FedEx Priority shipping is about $75.

One thing you have to watch for is holidays, they tend to shut everything down for major holidays.? In theory they got my package out before leaving for New Years...I have a FedEx tracking number and hope FedEx in China doesn't shut down until after the box has left the country.


* Shande Electric Factory, 
--
Jerry Durand, Durand Interstellar, Inc.  
tel: +1 408 356-3886, USA toll free: 1 866 356-3886
Skype:  jerrydurand

Re: Horsepower Resistor

Den
 

Will give it a try.
Thanks

--- In 7x12minilathe@..., "andyf1108" wrote:

I'm reasonably familiar with KB's website, Den, having used it to find UK distributors.

If all else fails, you could make one up yourself. Ceramic cased, 0.1 ohm 10 watt wirewound resistors seem pretty readily available, and four of those in parallel would give you 0.025 ohms. They would handle 40W, which is probably an unecessarily high rating for the job, but there's no harm in that.

Andy

--- In 7x12minilathe@..., Den Strods wrote:

That was quick.
Thanks for your effort, I will ring them in ?the morning.
Cheers
Re: Horsepower Resistor

Den
 

I rang ABB Australia Pty Limited this morning and got a phone number for one of there retail outlets. Rang the second outlet and was told they were out off stock. They really didn't want to help me as I was told they would have to order from ABB Australia Pty Limited who would charge them postage fees and they would also charge me postage fees, so for a $4 part that would fit into an envelope it would cost $30.
I will be looking elsewhere, no wonder we by from China on the net.
And Australian Business wonders why people by from overseas.
Cheers

--- In 7x12minilathe@..., "andyf1108" wrote:

The "dealer finder" on the KB Electronics website shows a single distributor in Australia:

Country/Area: Australia
City: Seven Hills, NSW
Name: ABB Australia Pty Limited
Phone: 02-9674-5455
Fax: 02-9674-2495
E-mail: sales.au@...
Web Site: www.Baldor.com.au
Product Line(s): AC & DC Drives
Stocking: This is a stocking distributor

Andy



--- In 7x12minilathe@..., "Den" wrote:

I am trying to by a .025 plugin horsepower resistor for a KBCL-240D board.I found some on US ebay for $5 but postage to Australia is $26.
Is there some place that sells these with reasonable postage to Australia.
I have probably missed the obvious.
Cheers and thanks for your help.
Re: Horsepower Resistor

 

开云体育

Try Jaycar or Alltronics. In the eastern suburbs of Melbourne I would recommened going to Trucotts Electronic World.

Cheers,

Andrew in Melbourne


On 03/02/13 22:39, MERTON B BAKER wrote:

?

Surely there are radio supply stores in Australia? I know it's vast &
populated mostly around the edges, but I would think that asking around
would turn up a solution.

Mert

-----Original Message-----
From: 7x12minilathe@...
[mailto:7x12minilathe@...]On Behalf Of Den
Sent: Sunday, February 03, 2013 4:40 AM
To: 7x12minilathe@...
Subject: [7x12minilathe] Horsepower Resistor

I am trying to by a .025 plugin horsepower resistor for a KBCL-240D board.I
found some on US ebay for $5 but postage to Australia is $26.
Is there some place that sells these with reasonable postage to Australia.
I have probably missed the obvious.
Cheers and thanks for your help.

------------------------------------

Yahoo! Groups Links
Re: Boring bar setup question

 

Hi John.

Yes, its a through hole. A couple of them actually.

One starts as solid bar, drilled to 1/2" then bored out to .625" or so to the proper depth to leave a .480" section with the 1/2" hole. This part goes over a stepped shaft.

The other starts with a .750" hole (I buy the material that way) and is bored out a bit to thread 13/16 x 26.

When it's all said and done the first part ends up turned and threaded for the second to screw over to become one piece. It's actually a handle upgrade.

I'll have to search D drill. I don't know what that is. And I don't have any way to make a HSS bar.

By the way, I've tried HSS inserts and have horrible chip welding. Do I just have crap steel inserts? Carbide has been so much better.

Thanks,

Ryan


John Lindo <bechetboat@...> wrote:

?

Hello Ryan.
You did not mention if this was a through hole that you have problems with.
If it is a blind hole,a boring bar with a flood coolant hole may work,to wash out the chips.
I agree with the comments about rake angles.
IMO carbide for cutting?aluminium never seems to work well.the chips tend to stick to the tip even with WD 40 as a cutting lubricant.
Try using a home made boring bar with a HSS tool bit.,and or a D bit drill made out of 3/4 " drill rod.
Just for interest,how did you get the hole roughed out in the first place?
If a through hole have you thought about boring from both ends,skimming the outside diameter and using a soft jaws in a 3 jaw chuck,
or a 4 jaw chuck, using a Dial indicator to get the concentricity when boring from the other end.

John L
Spain.

From: cnc sales <gcode.fi@...>
To: 7x12minilathe@...
Sent: Sunday, February 3, 2013 6:55 PM
Subject: Re: [7x12minilathe] Boring bar setup question

?
Hi Ryan !
For good results, boring holes are typically limited to about 1.5-2x boring bar diameter.

As such, a 3/8 boring bar is only good to about 1/2 inches.
After this it will chatter with variable results.

All lathe tools work well only upto about 1-3x their size.
Ie a 1/2 inch tool will only work well to 1-1.5 inches deep.

However..
Alu is easy.

Your problem is rake.
CCMT is 7 degrees positive and you need to maintain this, *especially* when doing deep bores.
With a -5 degrees boring bar, you are losing the benefits of the insert, and greatly increasing the problems of the overly long, slim, thin bar.

It *can* be done with a 3/8 in alu but not well, imo.
You need to have at least 7 degrees rake, even? a bit more.

If you can make (buy) another bar (any steel) of near .7 inches, and have the bit be at zero-1 degree rake, it will go vastly better.
For alu, at .75 inches or about 18 mm, I would recommend about 1000 rpm, 0.1 - 0.06 mm cuts.


?
Hi group!

I recently bought a 3/8 indexable boring bar that uses CCMT inserts. The bar has 5° negative built in. I'm using CCGT high polish 21.51 inserts and have a huge amount of chatter. I'm doing a 3/4 inch diameter hole just over 3" deep in 6161 aluminum.

I've tried the bar above center and on center. Above seems to chatter a bit less but I still can't get a nice cut.

Wrong insert, bad setup? Do I need a different bar? Just too deep of a hole and I'm going to have to live with it?

Any tips, tricks, hints, etc will be greatly appreciated!

Ryan

-- 
-hanermo


Re: Horsepower Resistor

Jerry Durand
 

开云体育

On 02/03/2013 06:49 AM, Mark Schwiebert wrote:
Look for a supplier ,on ebay from china,most offer a free economy shipping.
I read the Chineese Govt is smart enough to allow super cheap shipping ,by putting mail on US bound ships,flights,etc. to allow exports to go out with out a customer worring about excess costs.
You think our Govt.,would do this to try to get US made goods out ,and increase jobs,& commerce.
The china made components are so cheap,I usuall buy 10.00 worth,and have spares,as I have found brand new ones that did not work either.


Our company buys items from China fairly often and the shipping is always amazing.? For a current customer project I need some high current solid state relays.? In the USA a 40 Amp relay is around $47 each plus shipping.? I ordered ten of them from the factory* and the total WITH FedEx Priority shipping is about $75.

One thing you have to watch for is holidays, they tend to shut everything down for major holidays.? In theory they got my package out before leaving for New Years...I have a FedEx tracking number and hope FedEx in China doesn't shut down until after the box has left the country.


* Shande Electric Factory, 
-- 
Jerry Durand, Durand Interstellar, Inc.  
tel: +1 408 356-3886, USA toll free: 1 866 356-3886
Skype:  jerrydurand

Re: Boring bar setup question

 

Thanks!

Do you think a "P" insert (11°) would help? It's only 6° but better than the 2 I have now.

cnc sales <gcode.fi@...> wrote:

?

Hi Ryan !
For good results, boring holes are typically limited to about 1.5-2x boring bar diameter.

As such, a 3/8 boring bar is only good to about 1/2 inches.
After this it will chatter with variable results.

All lathe tools work well only upto about 1-3x their size.
Ie a 1/2 inch tool will only work well to 1-1.5 inches deep.

However..
Alu is easy.

Your problem is rake.
CCMT is 7 degrees positive and you need to maintain this, *especially* when doing deep bores.
With a -5 degrees boring bar, you are losing the benefits of the insert, and greatly increasing the problems of the overly long, slim, thin bar.

It *can* be done with a 3/8 in alu but not well, imo.
You need to have at least 7 degrees rake, even? a bit more.

If you can make (buy) another bar (any steel) of near .7 inches, and have the bit be at zero-1 degree rake, it will go vastly better.
For alu, at .75 inches or about 18 mm, I would recommend about 1000 rpm, 0.1 - 0.06 mm cuts.


?

Hi group!

I recently bought a 3/8 indexable boring bar that uses CCMT inserts. The bar has 5° negative built in. I'm using CCGT high polish 21.51 inserts and have a huge amount of chatter. I'm doing a 3/4 inch diameter hole just over 3" deep in 6161 aluminum.

I've tried the bar above center and on center. Above seems to chatter a bit less but I still can't get a nice cut.

Wrong insert, bad setup? Do I need a different bar? Just too deep of a hole and I'm going to have to live with it?

Any tips, tricks, hints, etc will be greatly appreciated!

Ryan


-- 
-hanermo

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