# 5c collet chuck



## kd0afk (Sep 30, 2013)

I finally ordered the 5c collet chuck from metal lathe accessories.  Should be fun and educational.


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## Philjoe5 (Sep 30, 2013)

If you are going to use the one that attaches to a backplate I have one and I like it a lot for doing work close to the chuck.  It's great for turning square stock too if you get the square collets.  

I did fiddle with mine a bit when I set it up to get TIR of 0.002".  You can do better with effort.

I use the independent 4 jaw for work that demands it.

Cheers,
Phil


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## Sshire (Sep 30, 2013)

That is my chuck-of-choice. It's rarely off the lathe. Over the past year, I've gotten a pretty full set of Hardinge collets (used).  Guess I've been lucky in that, even used, they check out to be very accurate. Hardinge starts out way more accurate than I need to be, so a bit a wear hasn't affected my work. Be careful with, imports. Some have been good, some way out and were returned.
Don't forget that hex and square collets are also very useful.
Collet block sets are inexpensive and very useful for holding small parts in the mill and my die filer. If you dont have one, get a spanner for the collet blocks. Way better than pump pliers.
Also cheap is a collet stop. My use is not so much for making multiple parts, but rather to keep small parts from sliding down the collet while I tighten it.


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## kd0afk (Oct 3, 2013)

He sent it today. I also ordered some used collets in the main sizes I use and a new collet to match the taper when I machine the chuck. I just wish I had a video camera to film the making. There are very few photos of this chuck on the interwebs and no videos of it. I'm surprised, because it's such a pretty chuck and you'd think that one would be proud of it. I have a video camera on my phone but no way to mount it. I'll have to put something together in aftereffects. 
Anyway, I'll post my progress.


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## kd0afk (Oct 3, 2013)

Philjoe5 said:


> If you are going to use the one that attaches to a backplate I have one and I like it a lot for doing work close to the chuck.  It's great for turning square stock too if you get the square collets.
> 
> I did fiddle with mine a bit when I set it up to get TIR of 0.002".  You can do better with effort.
> 
> ...



Im not sure if it does our not. I'll post photos when I get it.


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## kvom (Oct 4, 2013)

My advice is to get a full set of collets by 1/16" increments.   Ordering piecemeal can be frustrating.  Or you could consider having some "emergency: collets that you bore out to fit a size that you don't own a collet for.

One thing I most like about a collet chuck is that there are no chuck jaws to hit you when you're filing/polishing on the lathe.


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## Wizard69 (Oct 4, 2013)

kd0afk said:


> He sent it today. I also ordered some used collets in the main sizes I use and a new collet to match the taper when I machine the chuck. I just wish I had a video camera to film the making. There are very few photos of this chuck on the interwebs and no videos of it. I'm surprised, because it's such a pretty chuck and you'd think that one would be proud of it. I have a video camera on my phone but no way to mount it. I'll have to put something together in aftereffects. Anyway, I'll post my progress.



He does have one nice design for a collet chuck.   Apparently he didn't have a booth at this years Cabin Fever, I was a bit worried that something bad happened.   Metal Lathe Accessories has a really interesting line of products that hopefully will remain around for a long time.  

You are right about few pictures being on the net.   That is actually surprising as many seem to like the unit.


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## cobweb81 (Oct 4, 2013)

I built his "Die Filer" and the "Sine Plate".  All the castings were great quality and the instructions were good as well.  He does have nice products and and they are reasonably priced. Bought in person at the NAMES show a few years back.  Sorry not the greatest picture but the only one I had.  I like the collet chuck as well but haven't made it. Good luck with your build.


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## kd0afk (Oct 5, 2013)

kvom said:


> My advice is to get a full set of collets by 1/16" increments.   Ordering piecemeal can be frustrating.  Or you could consider having some "emergency: collets that you bore out to fit a size that you don't own a collet for.
> 
> One thing I most like about a collet chuck is that there are no chuck jaws to hit you when you're filing/polishing on the lathe.



The collets I bought looked to be in pretty good shape and they were like $2 each. I plan on getting a full set eventually, way ahead of you on that.


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## kd0afk (Oct 5, 2013)

Wizard69 said:


> He does have one nice design for a collet chuck.   Apparently he didn't have a booth at this years Cabin Fever, I was a bit worried that something bad happened.   Metal Lathe Accessories has a really interesting line of products that hopefully will remain around for a long time.
> 
> You are right about few pictures being on the net.   That is actually surprising as many seem to like the unit.



He's fine as far as I know, sounds to be in good health. I really like the name on the front of the chuck, I wish the rest of his castings were like that.


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## kd0afk (Oct 5, 2013)

Update.
Here she is. With all the pieces. You get drawrings, instructions, a catalog, a receipt, the castings:
Body, backplane, stock for the nut, 200 ball bearings (the instructions plan for an alternate ball race), three cap head screws, a set screw and drill rod for the key.
I'm painting it now with a black epoxy paint. She'll get three coats over three days and the I'll start machining it. The only thing I'll have problems with are the Tommy bar holes on the perimeter of the nut. Will probably use my dremmel on the tool post to spot the holes and set up a jig to finish them off. There are some groves as well but shouldn't be a problem.


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## Philjoe5 (Oct 5, 2013)

I didn't realize this was a casting kit.  It should be interesting.  Good luck with this project.  If you plan to post your machining work we'll move this to a work-in-progress.

Cheers,
Phil


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## kd0afk (Oct 5, 2013)

Philjoe5 said:


> I didn't realize this was a casting kit.  It should be interesting.  Good luck with this project.  If you plan to post your machining work we'll move this to a work-in-progress.
> 
> Cheers,
> Phil



That would be good. I'd like the build to have its own page,  thanks.


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## kd0afk (Oct 6, 2013)

I don't have a camera to videy the build but this morning I found a tripod mount for my Xperia Z phone and a flexible leg grippy tripod.


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## macmarch (Oct 9, 2013)

Philjoe5,

I'm somewhat surprised at the the runout you have with the 5C.  Bought mine about 2 years ago and its very rarely off the machine.  I turned the backplate on the mandrel then fitted the chuck. I always check when I put the unit back on and it is never worse than 0.0006" TIR measured on the collet mounting face.  The collets, however, well you only get what you pay for.  In $ we get charged about $17 each!
I wonder who will be the first to design and build a 5C collet that works the same as an ER32.  

macmarch (UK)


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## kd0afk (Oct 9, 2013)

macmarch said:


> Philjoe5,
> 
> I'm somewhat surprised at the the runout you have with the 5C.  Bought mine about 2 years ago and its very rarely off the machine.  I turned the backplate on the mandrel then fitted the chuck. I always check when I put the unit back on and it is never worse than 0.0006" TIR measured on the collet mounting face.  The collets, however, well you only get what you pay for.  In $ we get charged about $17 each!
> I wonder who will be the first to design and build a 5C collet that works the same as an ER32.
> ...


Is this a good thing or a bad thing? Where did you buy the chuck?


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## canadianhorsepower (Oct 9, 2013)

kd0afk said:


> I don't have a camera to videy the build but this morning I found a tripod mount for my Xperia Z phone and a flexible leg grippy tripod.


 

were did you purchase this
internet address if possible
thanks


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## kd0afk (Oct 9, 2013)

canadianhorsepower said:


> were did you purchase this
> internet address if possible
> thanks



What internet address?


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## petertha (Oct 9, 2013)

kd0afk said:


> What internet address?


 
I think Luc is asking for the web link to the vendor that supplies the kits you mentioned in this post - 5c chuck, Die Filer, Sine Plate etc.
You keep referring to him as "he". I was wondering the same question myself


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## canadianhorsepower (Oct 9, 2013)

petertha said:


> I think Luc is asking for the web link to the vendor that supplies the kits you mentioned in this post - 5c chuck, Die Filer, Sine Plate etc.
> You keep referring to him as "he". I was wondering the same question myself


 
you read my mind


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## chucketn (Oct 9, 2013)

kd0afk said:


> I finally ordered the 5c collet chuck from metal lathe accessories. Should be fun and educational.


 
kd0afk put it in the first post.
Chuck


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## Philjoe5 (Oct 9, 2013)

Hi Macmarch,



> I'm somewhat surprised at the the runout you have with the 5C



I bought the chuck and a set of 5C collets 1/8" - 1 1/8" by 1/16's for $200 USD so I knew what I was getting.  I mainly use these for working close to the chuck and I also have the square collets that are great for quickly turning square work.  I didn't expect TIR's that you are experiencing but now that you mention it I do have 1 expensive collet I bought at an auction.  I should check it but I think most of the runout is in the chuck itself,

Cheers,
Phil


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## macmarch (Oct 9, 2013)

Philjoe5,

I bought mine from Warco (UK). So I expect the carriage would be a bit pricey.  I am sure that the ones you get over there will be from the same chiwanese source. I paid £119 for the chuck.  Before machining the backplate I went the extra mile to ensure that the nose and backplate threads were absolutely clean.  The register was turned until the chuck recess started to go on.  A touch or two with fine emery and the recess went on a little.  Bring up tailsstock and use to drive on the chuck.  Remove the lot and drill and tap and fit bolts. Tighten down until the chuck is pulled hard back to the backplate. I apologise if I appear to be teaching how to suck eggs but getting a perfect fit is vital.  I was taught this way when I was an apprentice. (before England won the world cup.)  Also I am assuming that, like mine, your chuck is ground all over including the recess.


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## kd0afk (Oct 9, 2013)

Sorry, I'm dumb.
The address is http://www.statecollegecentral.com/metallathe/


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## macmarch (Oct 9, 2013)

If it helps then have a  look here,
http://www.warco.co.uk/128-lathe-collet-chucks


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## kd0afk (Oct 9, 2013)

macmarch said:


> Philjoe5,
> 
> I bought mine from Warco (UK). So I expect the carriage would be a bit pricey.  I am sure that the ones you get over there will be from the same chiwanese source. I paid £119 for the chuck.  Before machining the backplate I went the extra mile to ensure that the nose and backplate threads were absolutely clean.  The register was turned until the chuck recess started to go on.  A touch or two with fine emery and the recess went on a little.  Bring up tailsstock and use to drive on the chuck.  Remove the lot and drill and tap and fit bolts. Tighten down until the chuck is pulled hard back to the backplate. I apologise if I appear to be teaching how to suck eggs but getting a perfect fit is vital.  I was taught this way when I was an apprentice. (before England won the world cup.)  Also I am assuming that, like mine, your chuck is ground all over including the recess.



What I'm making is a kit from foundry castings. The important surfaces like the collet hole and taper are all machined in-situ so the run out should be very slight. 
I'm taking great care to make sure that the backplate is a press fit or close to it and that everything is dialed in. I bought this to increase my accuracy. I'm not going to rush it.


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## Philjoe5 (Oct 9, 2013)

Hi Macmarch,

Having prepared my backplate as you suggested and obtaining the result that I did, I concluded there is merit in the expression:
*you can't make a silk purse of a sow's ear*

But that is OK because the tool works for me as intended.  

Cheers,
Phil


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## kd0afk (Oct 9, 2013)

The directions for the hole call for it to be lapped.


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## Maxx (Oct 9, 2013)

I've been wanting the get a 5c chuck for about a year but farming isn't cheap and last year wasn't good and if corn prices don't go up  -  this year doesn't look great either....


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## kd0afk (Oct 9, 2013)

If anyone wants to donate a brass 5c collet to the cause, I could sure use one as a lap.


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## kd0afk (Oct 9, 2013)

Maxx said:


> I've been wanting the get a 5c chuck for about a year but farming isn't cheap and last year wasn't good and if corn prices don't go up  -  this year doesn't look great either....



This thin was less than $140 and it comes with everything but the cutting tools.


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## kd0afk (Oct 9, 2013)

When I machine the taper and I refine it using bluing and I get it to where it is bluing the while surface. Would I be safe to use a lap made by using the same taper angle to finish off the taper? I just checked and a brass collet isn't cheap. Lapping will render it useless and I don't want to ruin a new collet.


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## kd0afk (Oct 9, 2013)

Will I need to lap the taper? The directions don't call for lapping the taper, just the bore but I would like it to be as precise as I can make it.
With that said, I hate to bring the name Dremmel into the conversation, but has anyone had good results grinding with a Dremmel?


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## petertha (Oct 9, 2013)

kd0afk said:


> The address is http://www.statecollegecentral.com/metallathe/


 
Perfect, thanks! I'm interested in how the kit components go together. Can you elaborate...

(1) Is the backplate I assume? So you had to machine threads on the backside shown to fit your lathe spindle nose? And then a lip or something on the front side to fit a matching recess or something on (2) the chuck body? Do bolts retain the chuck on the backplate from behind?

(3) what is this chunk for?

Also looks like small bearing balls. Where do they go?


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## kd0afk (Oct 9, 2013)

The chuck has a backplate 1 and body 2. The slug 3 is the nut it is machined with threads that fit the collet. It goes between the backplate and body. The ball bearings are to fill the races that are to be cut on both sides of the nut and the corresponding surfaces of the backplate and body. The collet is drawn tight by the nut. Pretty ingenious design.


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## kd0afk (Oct 9, 2013)

As a side note I check the price of New hardinge 5c collets. Just a full set of fractional collets, round square and hex, not including meteoric or rectangular, a full set Will run around $10,000. WOW!


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## macmarch (Oct 10, 2013)

Oops!  Didn't realise that this was a DIY job.  I also make a fair number of 'tools' and if they do the job required then what matters how it looks or how 'accurate' it is.

Out of interest is it permitted on this site to put up pics and instructions of how to make a particular tool.  Or should I refer those that want it to a website?


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## Philjoe5 (Oct 10, 2013)

Hi Macmarch,

if you've made tools in your shop that other model engineers would be interested in then by all means post pictures in the "Tools" forum of this website

Cheers,
Phil


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## kd0afk (Oct 10, 2013)

I can't find a way to mount my phone to get a shot for video so it will have to be a combination of stills and hand held. My shop is tiny.


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## macmarch (Oct 11, 2013)

I'll take some pics of the first one.  Its an AVS for repetitive work.  Very simple but saves hours of work.
I had to make it when an apprentice but I have never seen one since.


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## kd0afk (Oct 13, 2013)

Tomorrow's the big day. Paint will be set and I can start machining. I was able to rig a skyhook style mount for my phone so I can film it after all.


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## Philjoe5 (Oct 13, 2013)

I'm looking forward to your progress

Phil


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## mc_n_g (Oct 14, 2013)

Built one about 2.5 years ago. It was a nice project to work on.
I would recommend some cheap C2 brazed carbide inserts to get through the bulk of the junk material.
I cut the taper for the collet using a carbide insert tool and using marking fluid on one of the collets.  I did not grind it.
The cast iron will chew up HSS if you try to use it on the skin.
Use the C2 until you get to a finishing cut.  You can even use the C2 on a finishing cut if you form a larger radius on it.
I found the quality of the iron to be very good and no inclusions.
Trepanning the deep pocket will be one of your challenges.  It will squeal and chatter. Have a good hook on the tool end and resharpen it as you go.
Have a large diameter boring bar to minimize deflection when boring the 5C hole.
Use a vacuum or a mask because the iron dust is going to go everywhere!
Take your time and plan out the measurements and know exactly how much you need to cut.
Final finish I went with various grades of silicon carbide sandpaper (OMG panic he used sandpaper) and then used fine grade emery paper for a polish.
I finally used a clear spray coat over the top. 
For me it was not about the 'beautification' but having a usable repeatable tool.
The 5C chuck gets used and swapped regularly
I get between 0 and 0.0004" when I take it on and off. This may not be acceptable to you but is works for me.
Around 6" mark I get 0.001" - 0.004" depending upon the collet. I bought some cheap collets and do not expect a whole lot better.
One last hint. Drill the tommy bar holes before you reach the final diameter. After drilling them drive wooden dowels in the holes so you do not get the 'chatter' impact from going over a hole.  Also do the sanding with the dowels in the holes as it leaves a nice edge to the tommy holes.  Remove the wood dowel rods with a screw to pull it out.







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## kd0afk (Oct 20, 2013)

Thank you for the first hand input on this. I'm to the trepanning stage now. I used a 1/2" bit for maximum rigidity and spent the better part of the afternoon grinding it to shape. I'll finish it up today and have at it.
The one problem I ran into is getting it centered. I opted for the best visual registration ad I could but it still looks like it wobbles a bit. Oh well, it's my first and ad long as it's accurate, that's all that matters to me.


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## kd0afk (Oct 20, 2013)

One thing, when I grind the rake into the trepanning tool, I want it to run nose to tail and not side to side right, like a parting tool?


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## kd0afk (Oct 20, 2013)

I just came from the shop and I think I'll leave the trepanning for the big dogs. I'll say when I've been licked and I think I'll go with the alternate ball race assembly. It calls for boring to the full depth the counterboring that to accommodate a boss that screws in. It duplicates the trepan and will work.


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## Swifty (Oct 21, 2013)

I just want to point out that when checking the taper with a collet, the collet will be sprung open, making it a slightly different taper.
If you have a solid 5C shank it would be ideal to use for checking the taper.

Paul.


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## kd0afk (Oct 21, 2013)

Swifty said:


> I just want to point out that when checking the taper with a collet, the collet will be sprung open, making it a slightly different taper.
> If you have a solid 5C shank it would be ideal to use for checking the taper.
> 
> Paul.


Everything if seen and read about cutting a collet taper says that you need to insert a piece of stock that just fits the collet i.e. If it's a 1" collet you use a 1" piece of stock to keep the collet expanded to its full size. You are suggesting the exact opposite.


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## mc_n_g (Oct 21, 2013)

I had a 3/8" collet with a 3/8" drill rod in it so I could handle it.  It also allows you to put pressure on the collet and see how the taper matched up when marked.
Forgot to mention you should make a plug that very closely matches the threads on your spindle for testing the back mounting plate.  This way you do not have to keep removing the chuck and possibly screw up your threading operation.  You would like to have the back plate with a flat surface so that it registers to you spindle at the same spot all the time.  I don't know what lathe you are making this on/for but make sure you have a good registration surface on the outside of your spindle.
Do not finish the outer cuts until you join the back plate with the front part.  This will assure you a smooth surface between the two.
Take extra care and measurements to make sure the lip of the back plate and the hole of the front portion are a very close fit.  You do this to make sure your front part will not wiggle out of registration between the two surfaces and if you ever need to take it apart (heaven forbid) it will not have play.
Not cutting the trepanned slot will give you plenty of time to cut extra iron!  I only slightly remember the option about cutting it all out and plugging.  Use good 1/4 or 5/16 screws at a minimum if there is room.


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## kd0afk (Oct 22, 2013)

I have both a 3 & 4 jaw chucks. If I make my spindle test plug and test it against the chuck I'm not using it should be ok right? I'm thinking there might be slight variations between the two chucks but I'm also thinking that it should be okay to use one as a tester.


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## kd0afk (Oct 22, 2013)

Mc n g, to make the test plug, did you actually thread the plug or just make it for the spindle register? It would make sense to make two, one a go/no-go plug for the register and a finished threaded plug for the perfect fit. Would be a handy set to have.


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## mc_n_g (Oct 22, 2013)

No I made the threaded plug to test the threads on the back plate so it does not have to be removed.
You need the surface of the back place to be machined(lathed) and slightly proud (as per drawing) so it interacts with the register on your spindle.
You want the back plate to touch the register/shoulder of the spindle so it comes to a solid stopping point.
This way all cuts are referenced to the same place and orientation in relation to the spindle.


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## Swifty (Oct 22, 2013)

kd0afk said:


> Everything if seen and read about cutting a collet taper says that you need to insert a piece of stock that just fits the collet i.e. If it's a 1" collet you use a 1" piece of stock to keep the collet expanded to its full size. You are suggesting the exact opposite.



All my 5C collets are sprung slightly open, the idea of putting a piece of material the exact collet size is a good one, but the problem is how do you close the collet down on the material.

Paul.


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## kd0afk (Oct 22, 2013)

I'll have to double check but when I put a rod the size that's marked on the collet it's almost a press fit. I guess I don't have that problem.


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## kd0afk (Oct 22, 2013)

I made my threaded plug. She turned out perfect, no play at all with both of my chucks.
I got the back side of the faceplate faced, the through hole bored at 1.375" and the shoulder bored to 1.510" the exact OD of my spindle. I just got done grinding the threading tool and I'll tackle the threads tomorrow, its late and I'm tired.


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## kd0afk (Oct 23, 2013)

I thought I'd get back out tonight and finish up the baseplate. We'll, my fear happened. I screwed up the threading. The bit I ground was wrong, not deep enough and it scraped the hole bigger. I didn't catch it till it was too late.
I emailed MLA, hopefully he can sell me a replacement.
Live and learn I guess. I'm just wondering if it can be saved maybe?
Life sux right now.


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## Swifty (Oct 23, 2013)

Bummer, any chance of putting in some type of insert?

Paul.


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## kd0afk (Oct 23, 2013)

Would tig welding to add material to the hole be a suitable fix for my rookie mistake or should I just start with a new backplate?


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## kd0afk (Oct 23, 2013)

Swifty said:


> Bummer, any chance of putting in some type of insert?
> 
> Paul.


I have the steel to do that. Probably thread it and use permanent locktite right?
I'm just sick about this.


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## kd0afk (Oct 23, 2013)

Another option if Andrew won't sell me the part I can always just buy a backplate from shars. I think they're around $20 or so.
Heck Cattail foundry can cast me one for less than $30


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## kd0afk (Oct 23, 2013)

Do they make 1-1/2"-8 helicoil?


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## kd0afk (Oct 23, 2013)

I discovered the mistake I made. I ground the threading tool from a old brazed carbide bit but didn't grind enough clearance. Rookie mistake.


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## Swifty (Oct 23, 2013)

kd0afk said:


> I have the steel to do that. Probably thread it and use permanent locktite right?
> I'm just sick about this.



Would be best to loctite and pin it some way, then you are not just relying on the loctite to hold when tightening up the collets.

Paul.


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## kd0afk (Oct 23, 2013)

Andrew suggested that I bore out the hole and make a plug thats .001" over and do a shrink fit. He said it wouldn't budge and pretty invisible. I was thinking of buying a backplate from shars but their 5" plate is $45. I have steel and a torch I'll try the plug first.


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## kd0afk (Oct 24, 2013)

I looked up the numbers for thermal expansion of cast iron. It said the temperature range is 32-212 F and 5.8 microinches /inch F.
I have no idea what that means. Can anyone explain it?


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## Swifty (Oct 24, 2013)

kd0afk said:


> I looked up the numbers for thermal expansion of cast iron. It said the temperature range is 32-212 F and 5.8 microinches /inch F.
> I have no idea what that means. Can anyone explain it?



I think that the expansion is probably measured on a straight piece a foot long. It's a bit hard to work out how much a round piece with a hole in the middle is going to expand. 

If I was going to do it, I would make the insert about .001" / .002" bigger on diameter, put the outer piece in the oven for 30 minutes at nearly it's highest setting, when ready grab the outer with oven mitts and place it over the waiting insert. (Don't do this on the kitchen bench / counter top). I usually have the insert sitting on a steel plate, make sure everything is square when you put them together.

Disclaimer: all advice given freely, but no responsibility . 

Paul.


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## kd0afk (Oct 24, 2013)

Will 2" dia be ok for the insert? The spindle is 1.5"


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## mu38&Bg# (Oct 24, 2013)

With a thermal coefficient of expansion of 5.8 microinches per inch per degree Fahrenheit, a piece of cast iron 1" long at 70°F would be 1.000005.8" long at 71° So if you want to shrink fit you'd have 2" at 70°F and 2.00104" at 250°F or 2.00209" at 430°F. If you make the interference too great, the cast iron can crack. Shoot for .001-.002" of interference as suggested.  Measure the bore and insert carefully and make sure the parts have a good surface finish. Putting the insert in the freezer gives you a bit of extra clearance to get things assembled. Once you begin sliding these together you will be committed.

On my Lathe rebuild I heated up a bearing and slipped it into place on the spindle. About 1 millisecond after the bearing grabbed the shaft, I realized I forgot to slip on a part that goes on before the bearing. Unfortunately this bearing is up a against a large shoulder with less tham 1mm behind the race. I had to make a puller to remove it.

Greg


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## kd0afk (Oct 24, 2013)

So, 2" should be big enough right? It will have 1/4" of material around the threads. Also, lets say, the surface finish is good on both parts and the insert is frozen and the iron is at 500F, how much time am I going to have to mate the two before they lock up? Milliseconds doesn't sound like a good margin for error.


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## ddmckee54 (Oct 24, 2013)

You're going to have to get out your algebra and maybe even your calculus to figure that one out.  If you know the exact size at ambient temperature, and you know the temperatures that you are heating and cooling the parts to, then you can calculate the clearance that you will have the instant you start to put them together.  Then you find the heating/cooling rates of the material and calculate how long it will take for that clearance to go away.  Let's just say you don't want to dilly-dally around if you want everything in the right place.

Don


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## kd0afk (Oct 24, 2013)

It's going to be; backplate from the oven to the steel plate on the floor and at the same time plug from freezer to backplate. Shouldnt take but seconds. Still nervous about it.


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## Swifty (Oct 24, 2013)

It's not for the faint hearted, you have to work quickly as it can grab in no time. 
Have the plug ready before you get the backplate from the oven, don't put the backplate on the floor first as you will lose heat straight away.

Paul.


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## kd0afk (Oct 24, 2013)

I just remembered that I have a big cast iron skillet. I think I'll put both in the oven so the backplate won't cool down so fast.


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## kd0afk (Oct 24, 2013)

I got the plug finished and it fits like it was meant to go on there. But I'm stuck till I can find my strap wrench. Oh well. I threaded the plug and machined the shoulder and then screwed it on to the spindle to true up the outside and I can't get it off now.


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## mc_n_g (Oct 25, 2013)

Trepanning sounds better and better from the beginning.
You have opened a whole new can of worms, but you are working through it.


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## kd0afk (Oct 25, 2013)

mc_n_g said:


> Trepanning sounds better and better from the beginning.
> You have opened a whole new can of worms, but you are working through it.


The plug I'm making has nothing to do with the trepan. I've still got to cut the trepan plug but the threaded insert is because I screwed the pooch on the backplate.
I'm machining the hole to accept the insert today.


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## kd0afk (Oct 25, 2013)

Looks like I'll be buying a new backplate. I cut the hole in the plate too large. I don't know how, I was extra careful but something happened.  found one for a boxford lathe that will work for less than $30


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## kd0afk (Nov 18, 2013)

This was a huge learning project.
There are a few more things I need to do to complete this. Bore and thread the nut, mount the ball race slug, machine all the bearing groves, drill and tap for the key and drill the tommy bar holes on the back end and she'll be ready to use.
I can't draw it in tight but I put a dti on it and it read .00015 tir. For my first complex project I think I did pretty well. I think also that once I'm able to draw the collet and tighten the nut the tir might go down a bit. The bore was machined in-situ so maybe it's the collet, I don't know at this point. I do know that the thing is a bit more accurate than my three jaw.


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## kd0afk (Nov 18, 2013)

I will probably be making a new nut when I get a new caliper. Somehow the thing wasn't true to it's own axis when I machined the grooves and holes. The slots are askew and the holes don't completely line up. No problem though I have the extra stock and I know how to correct the error.
All in all this was a fun project and I think I'll get some good use out of it.


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## mc_n_g (Nov 19, 2013)

Happy to see you enjoyed it even though you had a few problems. Part of learning.
Hope the rest of it comes out ok for you.  
Once you complete it and use it you will be happy with the results.
The accuracy is a very nice addition.


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## kd0afk (Nov 19, 2013)

mc_n_g said:


> Happy to see you enjoyed it even though you had a few problems. Part of learning.
> Hope the rest of it comes out ok for you.
> Once you complete it and use it you will be happy with the results.
> The accuracy is a very nice addition.


So .0015" tir is good?
I think what happened is that the washer I used on the jig wasn't completely flat so it was askew. The holes are not aligned. Also the main body is a few thousandths off and it's visually distracting.


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## mc_n_g (Nov 20, 2013)

I did not do any final boring of the 5C hole until I had everything together, including the threaded nut and bearing races, this way all errors would be minimized.
I did not do the final shaping of the outside of the chuck until everything was together.
The area where the two halves were joined was also finished in this final process so I could always get the chuck back together with minimal error.
If you bored the hole and taper when all parts were together try and determine where your error is.
Are you reading the error from the piece of metal sticking out from a piece of rod being pushed into the chuck?
How does that compare to the error using an indicator of the bored 5C hole?  If the 5C hole is almost 0 then you have a problem with your 5C collet.
Good is a relative measurement.  Is 0.0015" good to you?  I don't know.
Can you verify the proper seating on the threads when you take of and put back on the chuck?  Are the measurements in the TIR the same?
Too many variables to determine via text.


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## mc_n_g (Nov 20, 2013)

I just read your previous post again.  What is the TIR 0.0015" or 0.00015"?
They give completely different interpretations of accuracy.  
If it was the later I think that is much better and you do not have any problems with it.


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## kd0afk (Nov 20, 2013)

mc_n_g said:


> I just read your previous post again.  What is the TIR 0.0015" or 0.00015"?
> They give completely different interpretations of accuracy.
> If it was the later I think that is much better and you do not have any problems with it.


Sorry, .0015 is the correct measurement.


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## kd0afk (Nov 20, 2013)

The only part of the outside I did before assembly (minus nut) was to turn it so I could chuck it up. After machining the inside and the backplate I mounted the main body to the backplate. Then I bored the collet hole and the taper. Then I finished up the nose. Some of the collets I have are a very snug fit and I still haven't lapped the bore yet so the accuracy may improve. I will machine the nut today, assemble it and see what's up then. I will double check the runnout of the bore hole.


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## kd0afk (Nov 20, 2013)

I checked the spindle and it's running as true as I'm able to measure. 0.0000" runnout. I then checked the collet chuck bore and got a tir of. 0015" again. I will finish up what's left and check it again and see what's up. 
If it doesn't improve I don't know how to make it better. I took very light cuts with a very ridged boring bar and made sure everything was either locked down or tightened up. 
If it doesn't get any better It will still be way more accurate than my 3 jaw which is at a tir of. 003"


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## kd0afk (Nov 21, 2013)

I've been thinking about it and there should be absolutely no reason why the tir should be as bad as it is assembled or not. Can someone lend some advice on this? If the chuck is mounted on the lathe and fits perfectly (no play at all) and the hole is bored then it should be concentric right?


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## mu38&Bg# (Nov 22, 2013)

Is the runout on the chuck body consistent when the chuck is remounted? If it is, retruing the collet taper after everything is done should fix it.

If it's not consistent, poke around and see what's causing it:
Did you make sure the spindle and chuck threads and shoulder were clean when you mounted it to cut the collet taper?
Any burrs or ridges?
Chamfer to clear the radius on the shoulder?

Greg


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## kd0afk (Nov 22, 2013)

dieselpilot said:


> Is the runout on the chuck body consistent when the chuck is remounted? If it is, retruing the collet taper after everything is done should fix it.
> 
> If it's not consistent, poke around and see what's causing it:
> Did you make sure the spindle and chuck threads and shoulder were clean when you mounted it to cut the collet taper?
> ...


The runnout is the same if I recount. Spindle and Chuck threads are clean, I just got an air compressor and I love having a clean spindle. No burrs or ridges. The chick seats very nicely on the register. It is a Hardinge backplate already machined to fit the spindle. I had to take a skim cut to fit the spindle. 

Could I have been taking too light a cut? It was a brand new bit. Should I swap it out with an insert with a positive rake?
Also, I'm unfamiliar with insert terminology.


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## mu38&Bg# (Nov 22, 2013)

The collet taper was cut with no changes to the chuck (reassembly) and there is runout? Try to determine where this is coming from before cutting any more metal. Did you take the chuck apart? As suggested above, the exterior and taper should be the last operation to keep things in line. Cast iron should machine well. I used a carbide tippped boring bar when I trued my ER16 spindle, but that was made of steel. The only other thing I can think of is material variation, but I think this product is known to be good.

Greg


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## kd0afk (Nov 22, 2013)

dieselpilot said:


> The collet taper was cut with no changes to the chuck (reassembly) and there is runout? Try to determine where this is coming from before cutting any more metal. Did you take the chuck apart? As suggested above, the exterior and taper should be the last operation to keep things in line. Cast iron should machine well. I used a carbide tippped boring bar when I trued my ER16 spindle, but that was made of steel. The only other thing I can think of is material variation, but I think this product is known to be good.
> 
> Greg


I have repeatability when I disassemble.  There were no changes to the chuck after the bore and before machining the collet taper  
I'm completely stumped. When I was taking the light cuts (with the brand new insert) it was removing material the whole way and the sound was a nice cutting sound and consistent and not a scraping sound.


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## mu38&Bg# (Nov 22, 2013)

By repeatable you mean the runout is in the same place, or you consistently get the same TIR reading?

Now, I'm confused. You had the chuck together and cut the exterior and the taper. We are assuming it was true at this point because we expect it to be. After this we have to assume it was dismounted and/or disassembled. Now, you check it and it's not true. To me this means there was something behind the chuck backplate that threw it off when those cuts were made. If that's all it was, just skimming everything should fix it. This time, check the runout before moving anything. If there is still runout after cutting, something else is wrong. Could be material hardness is inconsistent, could be spindle bearings are loose/worn. It's an unusual situation you have, but somewhere there is an answer. A small nose radius tool with a sharp edge will help reduce tool pressure.

Greg


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## kd0afk (Nov 22, 2013)

dieselpilot said:


> By repeatable you mean the runout is in the same place, or you consistently get the same TIR reading?
> 
> Now, I'm confused. You had the chuck together and cut the exterior and the taper. We are assuming it was true at this point because we expect it to be. After this we have to assume it was dismounted and/or disassembled. Now, you check it and it's not true. To me this means there was something behind the chuck backplate that threw it off when those cuts were made. If that's all it was, just skimming everything should fix it. This time, check the runout before moving anything. If there is still runout after cutting, something else is wrong. Could be material hardness is inconsistent, could be spindle bearings are loose/worn. It's an unusual situation you have, but somewhere there is an answer. A small nose radius tool with a sharp edge will help reduce tool pressure.
> 
> Greg


There was nothing between the spindle and Chuck except for a thin coat of oil, no chips, no burrs, nothing.  I didn't think to check if the runnout position changes with removal and replacement of the chuck but the runnout amount is consistent.  And it's repeatable after disassembly and reassembly. Spindle bearings are in as good a shape that they could be in, spindle play (deflection) is .003" when I do a lift test. 
I will change the insert and take a skim cut and if that doesn't help I'll try the Dremmel and see if I can't grind it. 
I'm completely stumped on this. But it's typical with my life. I can do everything right and still get crapped on for my reward.


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## kd0afk (Nov 22, 2013)

Just to clarify, TRI is the from the high reading to the low reading and not how much above and bellow 0 right?  Zeroed on the low spot my dti goes from 0-.0015" that is TRI right?


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## Swifty (Nov 22, 2013)

TIR, or true indicator reading, is the total reading in one revolution of the workpiece. With .0015" reading, this would mean that the piece is .00075" off centre, because half the reading is below centre and the other half is above centre. Similar when using a 4 jaw chuck to machine an offset cam, to get .100" offset on a round piece, the indicator will show .200". 

Paul.


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## kd0afk (Nov 24, 2013)

I just checked and I'm at .001 tir and all but my oldest collet fits well. I can live with that. 
Thanks for the help.


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## kd0afk (Nov 24, 2013)

I just finished the body except for the bearing race. I still have the nut to thread and then I'll do all of the grooves at the same time. Can't wait to use the thing.


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## kd0afk (Nov 25, 2013)

It's finished. The runnout didn't improve but it didn't get worse either. I'm not sure what to lubricate the bearings with oil or lithium white grease. There really isn't a way to lubricate the chuck completely  unless it is disassembled.


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## kd0afk (Nov 26, 2013)

Today I'll make a new nut. Somehow my setup got tweeked and it came out horribly wrong. It works but it looks like poop. I have a different strategy this time and I think it'll come out much better.


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## kd0afk (Dec 4, 2013)

I don't know what happened but I chucked up a 1" piece of round bar in the collet chuck and I got .0005" tir. I can live with that. I guess the bore is concentric it's just out of round.
Since it's concentric would lapping the bore and taper help get rid of that pesky .0005"?


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## mc_n_g (Dec 4, 2013)

You are going to screw it up!  Let it alone.
 You are going to find that not all collets will give you that precision.
 I personally think you are playing with fire.
 You are not running a nth degree precision machine in a clean room to make parts down to the micrometer level.


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## kd0afk (Dec 4, 2013)

Yeah, I'm fine with it. I was just curious about the lapping.


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