How to make a two-headed penny?

rsilvers · Jul 17, 2005

I want to machine a two-headed penny. I read that you want to do it on the seam within a face rather than split it down the side. I tried to SuperGlue the penny to a round bar so I could turn it but the glue would not hold. Surface was flat and clean, etc. Should I use Epoxy? Is there collet which could hold it? Has anyone done this?

scphantm · Jul 17, 2005

when i saw someone doing trick quarters he had made a special chuck for his lathe that gripped the quarter directly. looked like he took some plate and cut it into thirds, then welded those thirds to the three jaws of his chuck, then turned the face of the plate and inlayed a spot just big enough for him to put the quarter in and tighten down the jaws.

toolmakerjim · Jul 17, 2005

first get 2 pennies the same year.
then get a 5-C emergency collet and bore it to slightly less than half the thickness of the penny.
face one penny leaving a post any size you want dia and height.
face the other penny and counterbore to accept the post allowing for a press fit.
press both halves together but dont tell anyone how you did it...jim

RAS · Jul 17, 2005

Piece of cake. Thickness of a penny: .060", .750" dia. Hold on .020", in a 5C collet, face off the tail side (

); do it with two pennies. Super glue together... voila!

RAS

scphantm · Jul 17, 2005

oh, and the inlay was exactly half the thickness of the quarter, that way he could turn the edge of the quarter, then reverse it in the chuck to cut the other half of the quarter off so he can epoxy it into the other piece.

John Michael · Jul 17, 2005

My Dad used to make a trick nickle, he would bore the nickle half way through the diameter of a penny, face off half a penny, silver solder the half penny to a half nickle and turn the OD of the nickle to match the penny so it would fit into the bored nickle. He would appear to have a penny in his hand, lay a nickle on top of it and pick up the nickle to find the penny gone. I still have one.

Guest · Jul 17, 2005

I won't be flipping for beers with any of
you guys, that's for sure.

stephen thomas · Jul 17, 2005

rsilvers,

are you saying bore out the "tails" on one penny just up to the rim, then turn the rim off the other face and reduce the thickness to press it into the other rim? sound pretty neat! I'd use an emergency collet, as has been described. Might need 2, one to hold the whole penny and one to hold the reduced diameter face while facing off the back. Or maybe with a 64ths set, could use stock size collets and make a good solid stop to set depth and flatten the penny against.

(wonder how many of us are going to be trying this as an interesting sunday project tomorrow?!?)

smt

Dave A · Jul 17, 2005

I wonder if "Big Brother" is watching??

rjibosh · Jul 17, 2005

Discovery channel had a show on the mint and coins. They showed a guy doing exactly what you are talking about. He used the emergency collet route. I use two collets and it works really well. When boring out the collet, use a boring tool with a little side rake and make the bore edge a v instead of right angle. This way it will grab the coin a little better.

Rick

matt_isserstedt · Jul 17, 2005

(wonder how many of us are going to be trying this as an interesting sunday project tomorrow?!?)

I am wondering where to get a 5C emergency collet in an Emergency!!! ????

rsilvers · Jul 17, 2005

http://www.wttool.com/p/1702-0320

This is going to sound basic, but -- I never used a collet on my lathe -- just chucks. I have a Grizzly 12x36. What do I need to use collets? Can someone give me the URL of what I need to buy to hold the collet?

Dave A · Jul 17, 2005

Here is a link to a collet closer for a Grizzley lathe, but I suspect it will not fit your model. This is what you need to use collets in a lathe.

http://www.grizzly.com/products/item.cfm?itemnumber=H5948

rsilvers · Jul 17, 2005

Thanks. I just googled for them and they all seem to be $400 to $1200. Seems like a lot, but I need one. Does anyone know of what specific one would be best for a 12x36 http://www.grizzly.com/products/item.cfm?itemnumber=G4003

I see someone made one: http://www.frugalmachinist.com/db.html

winchman · Jul 17, 2005

Holding a penny in a collet while you bore out one side is easy enough, but how do you hold the other penny while you're cutting down the OD?

Roger

Jon_Spear · Jul 17, 2005

For rsilvers:

A trick to make your own collet is to chuck up a cylindrical piece of aluminum, and bore out a recess to fit your workpiece, in this case it will be a hole the width and depth to fit your penny.

Then take the cylinder out of the chuck, and cut an "X" (with two slices on the bandsaw) into the end of the cylinder. The cuts should be deep enough to allow the walls of the recess to flex radially under applied pressure. Put a hose clamp around the outside of the cylinder, which will act like a collet closer. When you put the cylinder back into the chuck, make sure it goes back the way it was before removal, in cases where you need to maintain concentricity. You can also cut an asterisk-shaped pattern by using three cuts on the bandsaw, rotating the cylinder 60 degrees each time. The cuts will intersect in the middle of the cylinder.

I'm not sure if I have explained this clearly. I think I might be making it sound more complicated than it is.

-Jon

rsilvers · Jul 17, 2005

I will try it with a home-made collett in a 4-jaw chuck.

Jim S. · Jul 17, 2005

Winchman,
The reduced diameter coin needs to be done in two steps and is best done with a collet but I've done it with a 3 jaw chuck in a Unimat. First, grip the coin with half its edge and create a step on the other size, the diameter to fit into the bore of the other coin. Then, reverse the coin and grip it on the step and face off the other side. Press together and you're done.
Jim

rsilvers · Jul 17, 2005

Does anyone think Epoxy glue will hold during machining? I could then release it with a torch. I have a book on machining that says you can glue washers to a bar for thinning.

Jpfalt · Jul 17, 2005

Cost of lathe - $3950
Cost of collet closer - $675
Cost of the pennys - $.02

Cost of the look on your face when you flip it and the other guy calls "heads" - priceless

How to make a two-headed penny?

Cast Iron

Cast Iron

Titanium

Stainless

Cast Iron

Hot Rolled

Guest

Guest

Diamond

Titanium

Hot Rolled

Diamond

Cast Iron

Titanium

Cast Iron

Stainless

Hot Rolled

Cast Iron

Hot Rolled

Cast Iron

Aluminum

Similar threads