Re: Dead Center stuck in tailstock ram.
Make 2 wedges approx 10¡ã? with a slot in the middle the same diameter as the? exposed dead center. Squeeze them towards each in a vise between the dead center head and the tailstock barrel and they will force the center out. Here is a video from Mr Pete showing everything.
https://youtu.be/AtNM8-VUvrg
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Re: Dead Center stuck in tailstock ram.
Was actually thinking of drilling a small bore hole through from the back of the ram, and tapping it out with a small drift¡
Issue would be how hard is the ram itself gonna be, can it be easily drilled. It¡¯s probably surface hardened as it¡¯s a sliding surface, but perhaps not through?
Jeff
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Re: Dead Center stuck in tailstock ram.
Sometimes with these old machines the old oil drys and acts a bit like glue. Try soaking the part in petrol (gasoline) or paint thinners. This will dissolve the oil pretty quickly.
If it is still stuck its likely to be rusted in place. In that case try some heat to the outside.
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Re: Dead Center stuck in tailstock ram.
Use a piece of ice, or dry ice if you can find it, heat the tailstock ram, and use the ice to cool the center. Or take the patient way, and spray it with copious amounts of WD-40, or PB Blaster, and let it sit. Try to twist it every now and then. If it give, great! If not, spray it again! Then wait a few hours and try to move it again. Twisting force is most likely to help. Back and forth until it comes loose. Might take a week or so of alternate spraying with penetrating oil or something to dissolve the rust that may have formed, and trying to move it. Took a couple of weeks on tailstock for my lathe hitting it with alternating WD-40 & PB-Blaster, and twisting the center.?
Guy who documented his travails with this on a larger lathe hung a weight off a lever clamped to the center, and eventually the spraying penetrating oil loosened it enough that one morning he came out to find the center had twisted from the hanging weight.?
You could cycle through both methods, if it's a really old, really stuck center.?
Bill in OKC
William R. Meyers, MSgt, USAF(Ret.)
Aphorisms to live by: Good judgement comes from experience. Experience comes from bad judgement.? SEMPER GUMBY!
Expect in one hand, expectorate in the other. See which one gets full first.
On Monday, April 17, 2023 at 03:38:56 PM CDT, rcjge <jgpedwards@...> wrote:
Hey Folks
picked up a second Unimat SL and their is a a dead Center jammed in the tailstock ram.?
Tried really high quality oil to loosen, not budged so far. Held dead centre in bench vise soft jaws, still couldn¡¯t budge. Not much leverage mind since ram is out of tailstock. May have to reinstall ram in TS cast clamp tight and use for leverage with dead center held by vise¡?
Anyone been here?
Turns out tailstock ram is partly solid.
thinking of heating the ram some hoping it expands faster than dead center and loosen that way¡ ?
thoughts anyone?..
thanks,
Jeff
?
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Re: Milling table differences between Unimat 3 and DB200/SL1000 versions¡
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Dead Center stuck in tailstock ram.
Hey Folks
picked up a second Unimat SL and their is a a dead Center jammed in the tailstock ram.?
Tried really high quality oil to loosen, not budged so far. Held dead centre in bench vise soft jaws, still couldn¡¯t budge. Not much leverage mind since ram is out of tailstock. May have to reinstall ram in TS cast clamp tight and use for leverage with dead center held by vise¡?
Anyone been here?
Turns out tailstock ram is partly solid.
thinking of heating the ram some hoping it expands faster than dead center and loosen that way¡ ?
thoughts anyone?..
thanks,
Jeff
?
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Re: Milling table differences between Unimat 3 and DB200/SL1000 versions¡
The U3 version has deeper T-slots which means you can use both older SL and newer U3 T-nuts.
It is also a bit better made in general. The edges for example are better finished and are more square.
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Re: Casting an aluminum motor mount for DC motor upgrade
Steve:
Your rotary valve is on the Gazinza side of the dust collector, mine's on the Gazouta side.? I did a build log on Home Model Engine Machinist covering the build and installation.? There's pictures there if you're interested.
I initially had the cyclone discharging into a drum that had to be sealed similar to yours.? I built the airlock so that the discharge bin didn't have to be sealed.? It's less hassle now checking the level in the bin, or emptying it.
Don
?
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Re: Casting an aluminum motor mount for DC motor upgrade
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Re: Casting an aluminum motor mount for DC motor upgrade
If it was for the lathe setup, maybe, but as a vertical mill, the stress pulling down against the flat mount would bend over time, especially with any heat from the motor. I am going to try a sand cast in the next few days, I have enough aluminum ingots and I have the Petrobond setup. Until I get my new micro shop/shed built, I'm not using the Unimats for much anyway, and the lathe already has the factory mount.
Looking forward to it, should be fun!
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Re: Casting an aluminum motor mount for DC motor upgrade
Dave:
Nice looking 3D print you have there.? While you're is the process of learning how to cast the replacement bracket you might want to consider using a 3D printed bracket.? With enough perimeter wall thickness and plenty of infill it would take the loads that the 90-100W motors on a Unimat can throw at it.? PLA is more brittle and more temperature sensitive than ABS but it still works fine for an application like this.? Check out the MPCNC, there are guys there that are hanging 1HP routers off PLA brackets.? I built an airlock/rotary valve for my shop's dust collector, including the various odd-ball transitions for the dust collector.? I've been using it for a year or so with no problems.
I'm not saying that you shouldn't cast the bracket, but maybe you could use the PLA bracket as a prototype to see if there's anything you want to change.? I don't trust threads in FDM printed parts, at least not for something that gets removed/adjusted a lot, so I'd either embed a nut for the clamping screw, or use a threaded insert for that screw.
Don
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I use a 6" grinder in the garden, bolted to a plank which is in? turn held in a Workmate, as .
Paul B.
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Hi Bill, Which DMT fine diamond stone at $8 clearance price?were you referring to? Home Depot lists a lot of DMT products.
Inquiring minds, and all¡
Best,?
On Sunday, April 16, 2023, 6:30 PM, Steve Johnson <steve@...> wrote: Exactly!! Old school tools, old school books! Some things I like to have digitally, but this stuff I want on my desk/bench with coffee/grease stains on the covers.?
I ordered the Atlas book for 6" & 10" inch lathes, since none of them are Unimats, this seemed the most relevant. I think the basic lathe procedures should translate.
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Re: Casting an aluminum motor mount for DC motor upgrade
I seem to recall reading somewhere that the best aluminum for casting is aluminum from previous castings, so pistons and rims are great, but cans and? scrap plate aluminum will work, but aren't great.
-Dave
On Saturday, April 15, 2023 at 08:04:10 PM PDT, Steve Johnson <steve@...> wrote:
Thanks! My very long bucket list has lots of things related to making/building/fixing/modifying that I might only do a few times, but it feels good to attempt it, hopefully succeed, maybe find a new side hobby. I bought a pneumatic riveter years ago, the kind they used on 737s, and a crap load of various rivet sizes and countersink bits.? I used it to make a heated bed for a 3D printer, maybe I'll use it again, but a totally rewarding experience even if I don't.
Casting is one of those that I think will be more practical. I've been stockpiling aluminum parts and cans, thinking about approaching auto shops for old pistons/blocks (did you ever watch "The Worlds Fastest Indian", where he casts his own pistons in primitive sand molds? His formula for the perfect alloy was - one part Ford, one part Chevy!) Being able to design and print using plastics, and then use that as a basis for a mold is huge.?
Not too long ago, anything I tried to make had to be out of wood, or metal crudely shaped with a hacksaw and a hand drill. So many options today.
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Exactly!! Old school tools, old school books! Some things I like to have digitally, but this stuff I want on my desk/bench with coffee/grease stains on the covers.?
I ordered the Atlas book for 6" & 10" inch lathes, since none of them are Unimats, this seemed the most relevant. I think the basic lathe procedures should translate.
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If you must, cover EVERYTHING with oily rags, or paper towels, to catch the grit from the grinding wheels. Better to have a separate grinder though. Better still, to keep the grinder away from your lathe.?
Bill in OKC
William R. Meyers, MSgt, USAF(Ret.)
Aphorisms to live by: Good judgement comes from experience. Experience comes from bad judgement.? SEMPER GUMBY!
Expect in one hand, expectorate in the other. See which one gets full first.
On Sunday, April 16, 2023 at 05:47:55 PM CDT, Jeff R. Allen <jra@...> wrote:
My Unimat came with grinding wheels, which lead me to believe that it was possible (and common?) to sharpen tools right on the Unimat. What do y'all think about that?
Having used 6" grinders for years and years, I'd advise an 8" or 10" IF you can find and afford one, space, money, or time! Though 6" will do it. Even done it on a 5" with narrow wheels.?
?For the diamond hone, I'm fond of these:??Though I have also used the 3-hone set HF used to sell. And I recently picked up a DMT Fine diamond hone bench stone for under $8 on clearance from Home depot. Two, actually, and gave one to my youngest, for working on restoring pen nibs and the like. ;)
You could also use a piece of fine wet-or-dry paper or cloth stretched over a ice cream stick, or a file...?
Sharper the edge, the better your cuts, and the easier it cuts.?
Bill in OKC
William R. Meyers, MSgt, USAF(Ret.)
Aphorisms to live by: Good judgement comes from experience. Experience comes from bad judgement.? SEMPER GUMBY!
Expect in one hand, expectorate in the other. See which one gets full first.
On Sunday, April 16, 2023 at 02:39:19 PM CDT, Charles Kinzer < ckinzer@...> wrote:
Grinding tool bits has commonly been "lesson #1" in machine shop classes because it is so fundamental.? And if you don't get it at least somewhat right, nothing will work out very well.? Also, once you get a good idea of clearance and rake angles, you will understand that the same concepts apply to other cutting tools like milling cutters and twist drills, or even a bit used in a shaper or planer..
I recommend a typical 6 inch bench grinder and no smaller.? You CAN go smaller, but things will go a lot slower.? And I suggest trying to locate the grinder a little bit away from other machine tools, or make some barrier, to help keep grinding dust away.? Grinding dust is not good to get on lathe ways and such.
And consider getting a "wheel dresser" to make the wheel nice and straight across again when it gets rounded or cupped.? There is more than one type.? The most common has a bunch of wheels with teeth such that when you look at it you ask, "how in the heck can this possible work?"? But they do.? Another type has a diamond impregnated flat block on the end of a holding handle.
You can get fancier sharpening tools such as water cooled ones, but you really don't need them.
I also recommend getting a diamond hand hone.? This is an extremely useful little tool that way too many hobbyists don't know about.? After grinding the tool bit, a few swipes of the hand hone really puts a sharp edge on it.? And it can also be used to refresh a slightly dulled edge, even with the tool bit still mounted in the tool holder.? You don't need a really expensive one (like you might find at a supply house like MSC Industrial).? Something in the $10 to $30 price range should be fine.? McMaster Carr has some low priced ones and there are low priced ones, and sets, on Amazon.
Charles E. "Chuck" Kinzer
On Sunday, April 16, 2023 at 12:08:18 PM PDT, Elliot Nesterman < elliot@...> wrote:
The Atlas Manual of Lathe Operation has ben digitized and can be downloaded from the Internet Archive. The South Bend book is digitized and available to borrow. Elliot Nesterman On 4/16/23 2:19 PM, Steve Johnson wrote: Thanks Gents! Excellent resources! Watching Mr. Pete as we speak, and
will look for those books!
-- Elliot Nesterman elliot@..."The finest jewel cannot disguise a flawed character."
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Hello Jeff,
While the Unimat came with grinding wheels and they were originally intended for use on the Unimat itself, it is not a good practice to follow and I will explain why. When the grinding wheel is dressed or in other words is trued with a diamond dresser or dressing stick it spreads grinding grit over the entire machine. This grit can get onto everything and cause excessive wear on mating surfaces. If grinding must be done then cover all exposed surfaces with a protective tarp or piece of plastic.
If it was my machine I just would not grind on or near the Unimat period.
Dick
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My Unimat came with grinding wheels, which lead me to believe that it was possible (and common?) to sharpen tools right on the Unimat. What do y'all think about that?
Having used 6" grinders for years and years, I'd advise an 8" or 10" IF you can find and afford one, space, money, or time! Though 6" will do it. Even done it on a 5" with narrow wheels.?
?For the diamond hone, I'm fond of these:??Though I have also used the 3-hone set HF used to sell. And I recently picked up a DMT Fine diamond hone bench stone for under $8 on clearance from Home depot. Two, actually, and gave one to my youngest, for working on restoring pen nibs and the like. ;)
You could also use a piece of fine wet-or-dry paper or cloth stretched over a ice cream stick, or a file...?
Sharper the edge, the better your cuts, and the easier it cuts.?
Bill in OKC
William R. Meyers, MSgt, USAF(Ret.)
Aphorisms to live by: Good judgement comes from experience. Experience comes from bad judgement.? SEMPER GUMBY!
Expect in one hand, expectorate in the other. See which one gets full first.
On Sunday, April 16, 2023 at 02:39:19 PM CDT, Charles Kinzer < ckinzer@...> wrote:
Grinding tool bits has commonly been "lesson #1" in machine shop classes because it is so fundamental.? And if you don't get it at least somewhat right, nothing will work out very well.? Also, once you get a good idea of clearance and rake angles, you will understand that the same concepts apply to other cutting tools like milling cutters and twist drills, or even a bit used in a shaper or planer..
I recommend a typical 6 inch bench grinder and no smaller.? You CAN go smaller, but things will go a lot slower.? And I suggest trying to locate the grinder a little bit away from other machine tools, or make some barrier, to help keep grinding dust away.? Grinding dust is not good to get on lathe ways and such.
And consider getting a "wheel dresser" to make the wheel nice and straight across again when it gets rounded or cupped.? There is more than one type.? The most common has a bunch of wheels with teeth such that when you look at it you ask, "how in the heck can this possible work?"? But they do.? Another type has a diamond impregnated flat block on the end of a holding handle.
You can get fancier sharpening tools such as water cooled ones, but you really don't need them.
I also recommend getting a diamond hand hone.? This is an extremely useful little tool that way too many hobbyists don't know about.? After grinding the tool bit, a few swipes of the hand hone really puts a sharp edge on it.? And it can also be used to refresh a slightly dulled edge, even with the tool bit still mounted in the tool holder.? You don't need a really expensive one (like you might find at a supply house like MSC Industrial).? Something in the $10 to $30 price range should be fine.? McMaster Carr has some low priced ones and there are low priced ones, and sets, on Amazon.
Charles E. "Chuck" Kinzer
On Sunday, April 16, 2023 at 12:08:18 PM PDT, Elliot Nesterman < elliot@...> wrote:
The Atlas Manual of Lathe Operation has ben digitized and can be downloaded from the Internet Archive. The South Bend book is digitized and available to borrow. Elliot Nesterman On 4/16/23 2:19 PM, Steve Johnson wrote: Thanks Gents! Excellent resources! Watching Mr. Pete as we speak, and
will look for those books!
-- Elliot Nesterman elliot@..."The finest jewel cannot disguise a flawed character."
|
Having used 6" grinders for years and years, I'd advise an 8" or 10" IF you can find and afford one, space, money, or time! Though 6" will do it. Even done it on a 5" with narrow wheels.?
?For the diamond hone, I'm fond of these:??Though I have also used the 3-hone set HF used to sell. And I recently picked up a DMT Fine diamond hone bench stone for under $8 on clearance from Home depot. Two, actually, and gave one to my youngest, for working on restoring pen nibs and the like. ;)
You could also use a piece of fine wet-or-dry paper or cloth stretched over a ice cream stick, or a file...?
Sharper the edge, the better your cuts, and the easier it cuts.?
Bill in OKC
William R. Meyers, MSgt, USAF(Ret.)
Aphorisms to live by: Good judgement comes from experience. Experience comes from bad judgement.? SEMPER GUMBY!
Expect in one hand, expectorate in the other. See which one gets full first.
On Sunday, April 16, 2023 at 02:39:19 PM CDT, Charles Kinzer <ckinzer@...> wrote:
Grinding tool bits has commonly been "lesson #1" in machine shop classes because it is so fundamental.? And if you don't get it at least somewhat right, nothing will work out very well.? Also, once you get a good idea of clearance and rake angles, you will understand that the same concepts apply to other cutting tools like milling cutters and twist drills, or even a bit used in a shaper or planer..
I recommend a typical 6 inch bench grinder and no smaller.? You CAN go smaller, but things will go a lot slower.? And I suggest trying to locate the grinder a little bit away from other machine tools, or make some barrier, to help keep grinding dust away.? Grinding dust is not good to get on lathe ways and such.
And consider getting a "wheel dresser" to make the wheel nice and straight across again when it gets rounded or cupped.? There is more than one type.? The most common has a bunch of wheels with teeth such that when you look at it you ask, "how in the heck can this possible work?"? But they do.? Another type has a diamond impregnated flat block on the end of a holding handle.
You can get fancier sharpening tools such as water cooled ones, but you really don't need them.
I also recommend getting a diamond hand hone.? This is an extremely useful little tool that way too many hobbyists don't know about.? After grinding the tool bit, a few swipes of the hand hone really puts a sharp edge on it.? And it can also be used to refresh a slightly dulled edge, even with the tool bit still mounted in the tool holder.? You don't need a really expensive one (like you might find at a supply house like MSC Industrial).? Something in the $10 to $30 price range should be fine.? McMaster Carr has some low priced ones and there are low priced ones, and sets, on Amazon.
Charles E. "Chuck" Kinzer
On Sunday, April 16, 2023 at 12:08:18 PM PDT, Elliot Nesterman <elliot@...> wrote:
The Atlas Manual of Lathe Operation has ben digitized and can be
downloaded from the Internet Archive.
The South Bend book is digitized and available to borrow.
Elliot Nesterman
On 4/16/23 2:19 PM, Steve Johnson wrote: Thanks Gents! Excellent resources! Watching Mr. Pete as we speak, and
will look for those books!
-- Elliot Nesterman elliot@... www.ajoure.net "The finest jewel cannot disguise a flawed character."
|
Grinding tool bits has commonly been "lesson #1" in machine shop classes because it is so fundamental.? And if you don't get it at least somewhat right, nothing will work out very well.? Also, once you get a good idea of clearance and rake angles, you will understand that the same concepts apply to other cutting tools like milling cutters and twist drills, or even a bit used in a shaper or planer..
I recommend a typical 6 inch bench grinder and no smaller.? You CAN go smaller, but things will go a lot slower.? And I suggest trying to locate the grinder a little bit away from other machine tools, or make some barrier, to help keep grinding dust away.? Grinding dust is not good to get on lathe ways and such.
And consider getting a "wheel dresser" to make the wheel nice and straight across again when it gets rounded or cupped.? There is more than one type.? The most common has a bunch of wheels with teeth such that when you look at it you ask, "how in the heck can this possible work?"? But they do.? Another type has a diamond impregnated flat block on the end of a holding handle.
You can get fancier sharpening tools such as water cooled ones, but you really don't need them.
I also recommend getting a diamond hand hone.? This is an extremely useful little tool that way too many hobbyists don't know about.? After grinding the tool bit, a few swipes of the hand hone really puts a sharp edge on it.? And it can also be used to refresh a slightly dulled edge, even with the tool bit still mounted in the tool holder.? You don't need a really expensive one (like you might find at a supply house like MSC Industrial).? Something in the $10 to $30 price range should be fine.? McMaster Carr has some low priced ones and there are low priced ones, and sets, on Amazon.
Charles E. "Chuck" Kinzer
On Sunday, April 16, 2023 at 12:08:18 PM PDT, Elliot Nesterman <elliot@...> wrote:
The Atlas Manual of Lathe Operation has ben digitized and can be
downloaded from the Internet Archive.
The South Bend book is digitized and available to borrow.
Elliot Nesterman
On 4/16/23 2:19 PM, Steve Johnson wrote: Thanks Gents! Excellent resources! Watching Mr. Pete as we speak, and
will look for those books!
--
Elliot Nesterman
elliot@...
www.ajoure.net
"The finest jewel cannot disguise a flawed character."
|
David James
rcjge
Unimat Matt
Bill in OKC too
Steve Johnson
OldToolmaker