Keyboard Shortcuts
ctrl + shift + ? :
Show all keyboard shortcuts
ctrl + g :
Navigate to a group
ctrl + shift + f :
Find
ctrl + / :
Quick actions
esc to dismiss
Likes
- 7x12MiniLathe
- Messages
Search
|
Re: Damaged compound
Michael,
toggle quoted message
Show quoted text
Thanks for the response. The tool was set dead centre which might be part of the problem. I was parting a 57mm diameter piece of cast iron. The overhang might have been too much resulting in it being to low. I feel that the chatter started as the thread was failing. I misread the situation and tightened the usual suspects. The gibs and carriage tend to be the culprits if there is chatter. These were tightened so that nothing would move. The only item moving was the one axis to do the plunge cut. I am looking for the right way of fixing IF it can be fixed at all. Cheers, Andrew On Tue, 2011-10-11 at 16:03 -0700, Michael Jablonski wrote:
|
|
Re: Damaged compound
¿ªÔÆÌåÓýHello
Andrew,
?
It
sounds like your parting tool was set too low on the work and was being pulled
in and under the work putting excessive stress on the tool post bolt. The
parting tool needs to be set dead on center. The chatter was probably from
turning?too fast. I know you didn't ask for any advice on why this happened
but thought I'd throw my two cents in.
?
Now
you ask if it is worth repairing the compound. If you can drill and tap the
compound to accept a large bolt then I'd try to repair it. I personally don't
think that a helicoil would hold up for long but that depends on how hard you
push the lathe. It's a cheap fast attempt at saving it.
?
Good
luck and please let us know how it turns out.
?
Michael
?
?
|
|
Re: Damaged compound
Jerry Durand
¿ªÔÆÌåÓýGenerally you do the insert yourself.? Do you have a drill press or mill?There's various types of inserts, you might be able to get by with a press fit one from the bottom.? Something like this (if pictures work in this group): On 10/11/2011 03:33 PM, Andrew wrote: I was thinking of seeing if a "helicoil" could work. Of course where do I get it done? More importantly, does the toolpost bolt have to be absolutely square to the surface? Cheers, Andrew -- Jerry Durand, Durand Interstellar, Inc. tel: +1 408 356-3886, USA toll free: 1 866 356-3886 Skype: jerrydurand |
|
Re: Damaged compound
I was thinking of seeing if a "helicoil" could work. Of course where do
toggle quoted message
Show quoted text
I get it done? More importantly, does the toolpost bolt have to be absolutely square to the surface? Cheers, Andrew On Tue, 2011-10-11 at 15:23 -0700, Jerry Durand wrote:
|
|
Re: Damaged compound
Jerry Durand
If I remember right from my mechanical engineering classes two full
toggle quoted message
Show quoted text
threads of a bolt *should* be all you need. That's assuming the bolt and nut are cut to spec out of proper materials. Other than that, do you have room in your tool post to use a larger diameter bolt? If not you'd have to make the hole quite a bit bigger and put in a threaded insert. On 10/11/2011 03:14 PM, Andrew wrote:
G'Day to all, --
Jerry Durand, Durand Interstellar, Inc. www.interstellar.com tel: +1 408 356-3886, USA toll free: 1 866 356-3886 Skype: jerrydurand |
|
Damaged compound
G'Day to all,
My task yesterday was to work on the cylinder for my Webster engine. I had hogged out the fins, the lower portions and drilled the inner diameter to 13mm. The last operation was to part off the work from stock when I noticed a lot of chatter. I stopped, cleaned up all the cast iron swarf and tightened the gibs. I tied again and the chatter was just as bad. I sharpened the tool which look OK and still no luck. When I tried after tightening the carriage and compound do nothing would move I tried again and the A2Z tool post (LMS #2461) came out of the compound. The holding bolt pulled the threads out of the compound. When examined I noticed the bolt only penetrated a 3 or 4 turns. I knew this as the threaded part was still there like a spring on the bolt. At this time I need to either fix or replace the compound. I also plan to buy or even make a suitable replacement for the supplied bolt. The reason for this post is to ask advice on if the compound is worth repairing and to warn others before they have problems. Cheers, Andrew in Melbourne |
|
Re: Threading question
M4x8 is a "metric special", i.e. not the standard thread for an M4.
toggle quoted message
Show quoted text
But it is available, e.g. the tap is available from Enco: Didn't find the die at Enco but if there's a tap, there's a die... somewhere ;-) Check the thread on the M5x8 bolt that secures the gear cover on your 7x machine against a 32 tpi thread gauge. The gib screws are M4x7, the common thread for M4 size. John --- In 7x12minilathe@..., Norm <w6nim@...> wrote:
|
|
Re: Threading question
Andrew Franks
¿ªÔÆÌåÓý
Best fit would probably be a BSC?(British Standard Cycle) 0.1563 (5/32)" x?32 tpi, 60¡ã. Still available from Tracy Tools in the UK, but probably unheard of on the other side?of the pond. Trouble is,?it was long ago superseded by the rather coarser , and I doubt if much BSC is around?nowadays. Mert's suggestion is probably the best way out. ? Andy? ? To: 7x12minilathe@... From: w6nim@... Date: Tue, 11 Oct 2011 12:47:23 -0700 Subject: Re: [7x12minilathe] Re: Threading question ?
On 10/11/2011 12:02 PM, GadgetBuilder wrote:
> > > Probably metric, M4x8 > > John > > --- In 7x12minilathe@... > , "nps0" wrote: >> >> I need to shorten a couple of gun cleaning rods. Found that the >> thread was an odd one - 32 tpi (no problem with this) but the OD is >> 0.153, which falls between 6-32 and 8-32. Machinery's Handbook >> doesn't list a 7xanything thread. IS there a #7 machine screw size? >> I guess that's why we have lathes - but a die would be nice to >> clean up the threads. >> >> Norm >> > > __ Hmmm -? Interesting combination.? I measured a 4mm screw at 0.155", so the diameter is right, but the thread is definitely 32 tpi, not the same as the 4mm screw.? It's a skinny rod, so there's not enough meat to go up to an 8-32 tap.? Guess it's lathe or nothing - - - Thanks for the suggestions. Norm |
|
Re: Threading question
¿ªÔÆÌåÓýOn 10/11/2011 12:02 PM, GadgetBuilder wrote:> > > Probably metric, M4x8 > > John > > --- In 7x12minilathe@... > , "nps0" wrote: >> >> I need to shorten a couple of gun cleaning rods. Found that the >> thread was an odd one - 32 tpi (no problem with this) but the OD is >> 0.153, which falls between 6-32 and 8-32. Machinery's Handbook >> doesn't list a 7xanything thread. IS there a #7 machine screw size? >> I guess that's why we have lathes - but a die would be nice to >> clean up the threads. >> >> Norm >> > > __ Hmmm -? Interesting combination.? I measured a 4mm screw at 0.155", so the diameter is right, but the thread is definitely 32 tpi, not the same as the 4mm screw.? It's a skinny rod, so there's not enough meat to go up to an 8-32 tap.? Guess it's lathe or nothing - - - Thanks for the suggestions. Norm |
|
Re: Carbide wheel
Jerry Durand
The carbide mills I use on our small CNC are made of bacteria sized
toggle quoted message
Show quoted text
powder that's been sintered. I don't know if any "solid" carbide is actually cast as one piece. On 10/11/2011 09:24 AM, Ray Kornele wrote:
Most carbide tools are high-temp BRAZED! I, too worked in a machine shop, --
Jerry Durand, Durand Interstellar, Inc. www.interstellar.com tel: +1 408 356-3886, USA toll free: 1 866 356-3886 Skype: jerrydurand |
|
Re: Threading question
Probably metric, M4x8
toggle quoted message
Show quoted text
John --- In 7x12minilathe@..., "nps0" <w6nim@...> wrote:
|
|
Re: Threading question
MERTON B BAKER
Welcome to made overseas. What I'd do in this case, is run the 8-32 tap in
toggle quoted message
Show quoted text
the holes and then tap the new spigots 8-32. I've run into this before. Fool around with some scrap first.. Mert -----Original Message-----
From: 7x12minilathe@... [mailto:7x12minilathe@...]On Behalf Of nps0 Sent: Tuesday, October 11, 2011 2:37 PM To: 7x12minilathe@... Subject: [7x12minilathe] Threading question I need to shorten a couple of gun cleaning rods. Found that the thread was an odd one - 32 tpi (no problem with this) but the OD is 0.153, which falls between 6-32 and 8-32. Machinery's Handbook doesn't list a 7xanything thread. IS there a #7 machine screw size? I guess that's why we have lathes - but a die would be nice to clean up the threads. Norm ------------------------------------ Yahoo! Groups Links |
|
Threading question
I need to shorten a couple of gun cleaning rods. Found that the thread was an odd one - 32 tpi (no problem with this) but the OD is 0.153, which falls between 6-32 and 8-32. Machinery's Handbook doesn't list a 7xanything thread. IS there a #7 machine screw size? I guess that's why we have lathes - but a die would be nice to clean up the threads.
Norm |
|
Re: Carbide wheel
my understanding is the material is actually a sintered combination of carbon and tungsten which forms tungsten-carbide particles.
toggle quoted message
Show quoted text
Machine tool cutters are formed by combining the particles with a softer cobalt (sometimes with nickel) matrix. The result is "cemented carbide". mike --- In 7x12minilathe@..., Leo Cormier <leocor@...> wrote:
|
|
Re: Carbide wheel
Ray Kornele
Mildly so. Not deafening, by a long shot. Just a moderate sound of air escaping. What surprised me was, in 1980 something, it only cost about $200. But, we had to install a refrigerated air dryer to supply air. Withouit the drier, the cooler kept shooting ice bullets, from frozen condensate from the air.
toggle quoted message
Show quoted text
We had some machining to do that had to be cooled, but, couldn't take liquid coolant. I don't think it was a hilsch. I assume that is a brand name? KrazyKyngeKorny (Krazy, not stupid) On Tue, Oct 11, 2011 at 9:42 AM, John Brookes <haiticare2011@...> wrote:
|
|
Re: Carbide wheel
hilsch vortex cooler. holy smokes! Was it noisy?
toggle quoted message
Show quoted text
John B On Oct 11, 2011, at 12:24 PM, Ray Kornele wrote:
Most carbide tools are high-temp BRAZED! I, too worked in a machine shop, |
|
Re: Carbide wheel
Ray Kornele
Most carbide tools are high-temp BRAZED! I, too worked in a machine shop,
toggle quoted message
Show quoted text
and ordered many of the tools, including M-5 for some special jobs that could not be cooled with coolant. I, also, ordered, and, installed a vortex cooler. Keeps things cool by producing super cold air. KrazyKyngeKorny (Krazy, not stupid) On Tue, Oct 11, 2011 at 7:41 AM, Leo Cormier <leocor@...> wrote:
** |
|
Carbide wheel
Leo Cormier
¿ªÔÆÌåÓý
"The green wheels don't actually grind the carbide, they pull little pieces of carbide away & grind the binder."
What binder? Carbide is a sintered material, which means that tiny pieces of carbide (almost powder) are compressed under great force and heated until it binds together as one piece. As far as "pull little pieces of carbide away" goes, that is exactly what grinding is. I spent 12 years in vary large machine shops (in shipyards) and we always used the green wheel to rough the brazed carbide tools and the wet diamond wheel to put a polish on just the carbide part of the tool. In a pinch, you can get by without the diamond. Leo |
|
Re: carbide wheel
A cheap alternative to a diamond wheel is the diamond knife sharpening blocks sold widely in places like harbor freight for 15$. They have a mix of grits, and are perfectly adequate for sharpening carbide tools. Typically you use water on them. I use it for sharpening both steel and carbide with excellent results.
toggle quoted message
Show quoted text
Tools have been sharpened by hand for thousands of years, and you get a better edge by hand. Its an interesting question if sharpening an insert is worth the trouble. I have a Silicon Carbide stone that Kennametal sells, but the diamond cuts much cleaner. The only time you need a diamond wheel is if you need to sharpen a lot of edge quickly, e.g., a professional knife sharpener, and there is really no reason to get it for sharpening a carbide lathe tool occasionally. I am a tool addict, so I bought a HF tool grinder and a diamond wheel from Enco. Total about $240. But since Ive got it, Ive used it maybe 5 minutes in 3 months! Another thing to consider is that a wheel produces an inferior result often. This is because hand sharpening has more control and hand-eye coordination. The wheel cuts so fast it is over in a few seconds, much too fast to control by hand. You basically shove the tool at the wheel and hope for a good result. Drills are easier on the wheel, and I have never sharpened a drill on the diamond block by hand. But it should be possible. I have no doubt a better result would happen. Recommendation: -Buy a 15$ diamond knife sharpening block from HF -get a squirt bottle for occasional water on block -optional- get a baking pan to contain the water. -Buy a fluorescent magnifying lap from HF. With a coupon, about $28. I have about 5 of them. A really good light, well-made. This will help you see the work piece edge. -optional - buy a stereo microscope from ebay. (120$). You will get spectacular results with it, because you will see the edge close up. JB On Oct 11, 2011, at 7:04 AM, john brookes wrote:
go diamond if you can. |
GadgetBuilder
to navigate to use esc to dismiss