# Idea for holding coin on mini lathe



## eltonc (Jan 5, 2014)

Hi everyone ,

Is there are better method to hold a coin without using collet? Since my sieg c0 lathe cant not use it.

I have tried to hold by chuck but  cutting tool will crash to it.

Thank.

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## Tony Wells (Jan 5, 2014)

Many variables, depending on what cuts you need to make, but some people use epoxy or superglue, and even 2 sided tape to temporarily adhere a coin to a flat face, either a faceplate, or simply a piece of stock faced flat. A little heat, or solvent and it will come right off.


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## eltonc (Jan 5, 2014)

Thank tony


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## pdentrem (Jan 5, 2014)

Hot glue works as well.

Get or make a set of soft jaws and make a shallow recess that will hold the coin. You can work the face but not the edges this way.
Pierre


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## brino (Jan 5, 2014)

hi eltonc,

it looks like you can get collets for the sieg c0 lathe, i found these ones:
http://www.arceurotrade.co.uk/Catal...aby-Lathe/C0-Baby-Lathe-Headstock-Accessories

they appear to have er16 and er25 collets, are those big enough diameter for what you need to hold?
it has a M14 x 1.0mm spindle thread right?

another option is using a device called a "spider", it is basically a spacer between the chuck face and jaw tips. it keeps your work from being pushed into the jaws.

here's one design:
http://www.homemodelenginemachinist.com/f13/easy-build-spider-small-lathe-5849/

good luck


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## rangerman (Jan 6, 2014)

Tony Wells said:


> Many variables, depending on what cuts you need to make, but some people use epoxy or superglue, and even 2 sided tape to temporarily adhere a coin to a flat face, either a faceplate, or simply a piece of stock faced flat. A little heat, or solvent and it will come right off.



That would be the best method and he doesn't have to buy anything special. 
If he can machine a _shallow pocket_ with an ID close to the OD of the coin at the end of the faced stock it would hold and auto-center the coin after gluing.


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## SE18 (Jan 6, 2014)

could you drill a hole in steel the size of the coin and then heat the steel and press the coin into the hole. When it cools, it would firmly hold it. To release coin, just heat up the steel form again.


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## eltonc (Jan 6, 2014)

brino said:


> hi eltonc,
> 
> it looks like you can get collets for the sieg c0 lathe, i found these ones:
> http://www.arceurotrade.co.uk/Catal...aby-Lathe/C0-Baby-Lathe-Headstock-Accessories
> ...



Wow.. you are my saver, thanks !


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## SE18 (Jan 6, 2014)

Q about the spider. I went thru the very interesting spider URL provided and downloaded the how-to photos:

If you lack collets like I do on my 9A South Bend, then making a set of spiders would be the next best option?


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## SE18 (Jan 6, 2014)

also, wouldn't you need a spider sometimes for a 4-jaw chuck too?


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## David S (Jan 6, 2014)

SE18 said:


> also, wouldn't you need a spider sometimes for a 4-jaw chuck too?



Yes I have a couple of different thickness ones for my 4 jaw


David


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## cascao (Jan 6, 2014)

How about a step chuck like this?


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## brino (Jan 6, 2014)

cascao said:


> How about a step chuck like this?



Hi Cascao,

The looks neat, I haven't seen that before.
It looks like it's split, and so must have a taper shank, and get pulled into a spindle taper by a draw-bar?
Is that one a 5C collet taper?

It may not help elton since his sieg C0 does not seem to have a tapered spindle, but still interesting.
Thanks for posting it!


eltonc,

I saw a few other spider links but could not find them before.

here's a few:

http://bbs.homeshopmachinist.net/threads/24007-Chuck-spider-(pic) 
http://www.royalprod.com/product.cfm?catID=12


there was an even simpler design that I cannot find again.....
it was basically three pieces of pipe that were faced off to exactly the same length, then had a strip cut out of the side of each. They ended up looking like long "C" shapes.
The "C" was made to grab onto each chuck jaw and sat "under" the work, between the chuck face and the work, and between each jaw and the lathe centre-line, and spaced the work out to the end of the jaws.
The big advantage of this type is that they were a "spring fit" onto the jaws, and didn't need to be held in place while tightening the chuck.
I will keep looking for those pictures......

(again could use four pipe pieces for a 4-jaw chuck)


brino


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## cascao (Jan 7, 2014)

1- You can turn one like this in your 3 jaw chuck. You do not need draw bar and taper thing.

2- Mark where jaw 1 is clamping.

3- Out of a lathe cut the 3 grooves until near the centre.

4- Clamp on 3 jaw chuck again on the same place to keep things centered.

5- When you tight the chuck, the coin will be hold.


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## Tony Wells (Jan 7, 2014)

I have my doubts about a small chuck having 2 piece jaws, but if it does, you might do this:

http://www.hobby-machinist.com/showthread.php/17043-Easy-Soft-Jaws?highlight=soft+jaws

Of course, a shallow bore to hold a coin instead of bored thru.


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## DAN_IN_MN (Jan 7, 2014)

eltonc said:


> Hi everyone ,
> 
> Is there are better method to hold a coin without using collet? Since my sieg c0 lathe cant not use it.
> 
> ...





Tony Wells said:


> Many variables, *depending on what cuts you need to make,* but some people use epoxy or superglue, and even 2 sided tape to temporarily adhere a coin to a flat face, either a faceplate, or simply a piece of stock faced flat. A little heat, or solvent and it will come right off.



I like Tony's question.  What type of cuts are you doing?  How many are you doing?  What accuracy do you need to keep?


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## eltonc (Jan 7, 2014)

To all of you:

After reading all  suggestion , making a set.of spider should solve my problem.  Thank for all of you guyS!!

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## eltonc (Jan 7, 2014)

Tony Wells said:


> I have my doubts about a small chuck having 2 piece jaws, but if it does, you might do this:
> 
> http://www.hobby-machinist.com/showthread.php/17043-Easy-Soft-Jaws?highlight=soft+jaws
> 
> Of course, a shallow bore to hold a coin instead of bored thru.



Another good application , this is more easier to build. I will try it in coming week, thanks.

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## eltonc (Jan 7, 2014)

DAN_IN_MN said:


> I like Tony's question.  What type of cuts are you doing?  How many are you doing?  What accuracy do you need to keep?



Actually , i want to make a spy coin which just hollowing the coin ( what kind of cut do you think? )

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## DAN_IN_MN (Jan 7, 2014)

eltonc said:


> Actually , i want to make a spy coin which just hollowing the coin ( what kind of cut do you think? )
> 
> Sent from my Galaxy Nexus using Tapatalk




I don't have a clue.  Honestly.    What modifications would you want to make to a coin?

I'm trying to help..... if you don't want help...don't post.

Not everyone is thinking the same way you are.


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## schor (Jan 8, 2014)

Spy coin.


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## eltonc (Jan 8, 2014)

DAN_IN_MN said:


> I don't have a clue.  Honestly.    What modifications would you want to make to a coin?
> 
> I'm trying to help..... if you don't want help...don't post.
> 
> Not everyone is thinking the same way you are.



I see,  i want to hollow out the coin as above photo . Thanks.

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## sliverr2 (Jan 12, 2014)

eltonc said:


> Hi everyone ,
> 
> Is there are better method to hold a coin without using collet? Since my sieg c0 lathe cant not use it.
> 
> ...


I have made 2 sided half dollars and to hold them i chucked up a piece of aluminum and bored a recess slightly smaller than the od of the coin and tapped (with a hammer) the coin into the recess . It worked very well be sure to put a thru hole in the aluminum so you can tap the coin out when done


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## Dan_S (Jan 13, 2014)

take a chunk of bar stock and do the following to it.

1. turn it to a diameter no more than 1/8" (3/32" or 1/16" might be better depending on material) larger than the coin you want to work on. 
2. face the end
3. bore a recess in the end just large enough to hold the coin
4. through drill the bar, make the hole slightly smaller than the recess. You need a surface to register the coin on
5. slit the bar length wise with a band saw or hack saw

you now have a custom collet, that you can chuck in a standard 3 or 4 jaw.


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