Hyd. Puncher / Coin planchets

[Scrapper]

Hello everyone,
Hope u all r doing well.
I am curious whether someone has tried to produce coin planchet with a Hydraulic punching machine? Would it work? ((Such as CH-70))

honestly, I am researching the most effective method for highly intricate planchet production out of a 1mm thick Silver/Aluminum/Gold plate.

Punching ? Lost wax casting? Sand casting? Laser cutter ?


Any experience or suggestion is highly appreciated

 

[Yggdrasil]

Hello everyone,
Hope u all r doing well.
I am curious whether someone has tried to produce coin planchet with a Hydraulic punching machine? Would it work? ((Such as CH-70))

honestly, I am researching the most effective method for highly intricate planchet production out of a 1mm thick Silver/Aluminum/Gold plate.

Punching ? Lost wax casting? Sand casting? Laser cutter ?


Any experience or suggestion is highly appreciated

Welcome to us.
It all depends on what you have available and how many you plan to make.

 

[4metals]

I have a few clients who cast their refined Silver from their Silver cells into long book molds and pass them through a rolling mill to a standard thickness and use a punch press to punch out planchets. One refiner stamps the purity on the planchet and uses a reeding mill to make grooves on the edges.

None of the operations I know of produce large quantities of these planchets which is why a manual pour book mold is used. Larger producers use continuous casting machines to produce the long strips, but that is on a larger scale.

The coin and bullion bar market for Silver in the US has suffered a setback because when premiums were high, they made a lot of money. Then everyone got into it and the margins plummeted. I do not know how that effected your potential market but before you invest you should check.

 

[Scrapper]

I have a few clients who cast their refined Silver from their Silver cells into long book molds and pass them through a rolling mill to a standard thickness and use a punch press to punch out planchets. One refiner stamps the purity on the planchet and uses a reeding mill to make grooves on the edges.

None of the operations I know of produce large quantities of these planchets which is why a manual pour book mold is used. Larger producers use continuous casting machines to produce the long strips, but that is on a larger scale.

The coin and bullion bar market for Silver in the US has suffered a setback because when premiums were high, they made a lot of money. Then everyone got into it and the margins plummeted. I do not know how that effected your potential market but before you invest you should check.

Welcome to us.
It all depends on what you have available and how many you plan to make.

I just need smth around 20 coins, however the intricate details are of most importance not the time it takes.
For a well detailed coin I believe I should make a planchet first, then Stamp it with press machine rather than casting the hole coin all at once. Is that right?
But what about the planchet itself? What method gives a more precise 1mm thick planchet? Punching the rolled plate? Or casting?

 

[Yggdrasil]

I just need smth around 20 coins, however the intricate details are of most importance not the time it takes.
For a well detailed coin I believe I should make a planchet first, then Stamp it with press machine rather than casting the hole coin all at once. Is that right?
But what about the planchet itself? What method gives a more precise 1mm thick planchet? Punching the rolled plate? Or casting?

We are for the most part refiners not jewelers or coin producers.
What material?
Will a small CNC router do the job?

 

[4metals]

For a well detailed coin I believe I should make a planchet first, then Stamp it with press machine rather than casting the hole coin all at once. Is that right?

This is the way it is typically done.

But what about the planchet itself? What method gives a more precise 1mm thick planchet? Punching the rolled plate? Or casting?

Punching the rolled plate is the typical approach here in the USA

 

[Scrapper]

We are for the most part refiners not jewelers or coin producers.
What material?
Will a small CNC router do the job?

silver & aluminum ... well no idea about the laser router! thanks, it does worth to research it.

 

[Scrapper]

This is the way it is typically done.

Punching the rolled plate is the typical approach here in the USA

Good, so i'm on the right path
regarding the Press machine & Punching, i'm not very expert., would a Press machine does the punching as well ?
I have searched & watched a lot on youtube, a Hydraulic Puncher (such as CH-70) moves slowly to punch the plate, and the planchets seemed a bit bent with some dents over the edge..
but a Hyd Press machine's jack movest quite fast, excerting an impact like Press...that is more suitable for stamping(minting) the coin...
the question arises is, would the press machine be able to punch or not ?

any ideas, or experience ?

 

[4metals]

The press simply applies the force to either punch out the planchet or to punch your coins details into the planchet. So the same press can do both but requires a separate die for each. To make 20 coins the cost and machining of the dies will exceed the value of the coins. The return on investment goes up proportional to the automation built into the process.

 

[Yggdrasil]

silver & aluminum ... well no idea about the laser router! thanks, it does worth to research it.

I said nothing about a Laser.
Just a plain CNC router, it do cost a bit though.
If not for the coin, it is perfect for the planchet.

 

[4metals]

The trouble with a CNC router is you remove Silver weight from the planchet. Stamping a planchet does not change the weight. Not that it cannot be done, it's just messy and you are chasing Silver turnings all about the shop.

 

[Shark]

Use the router to cut your dies. Then stamp the coin from the die. Otherwise 4metals is right, your wasting a lot silver from the shavings.

 

[nickvc]

For the planchets which if you want flat perfect rounds will need to be punched out of rolled flat sheet of the correct thickness , I’m thinking at 1 mm thick a hand press should do the job it’s possible that you could include the image in the die at the same time as you punch out the coins if it’s not too detailed or high relief.

 

[Yggdrasil]

Due to a language glitch, I assumed planchet was the tool used to stamp the metal.
Sorry about that.
a CNC router would be fine for the tool, not so much for the individual coin.

 

[grainsofgold]

for 20 , contact a minting company and buy them. Less money than gearing up to make them.

 

[Scrapper]

I said nothing about a Laser.
Just a plain CNC router, it do cost a bit though.
If not for the coin, it is perfect for the planchet.

But I researched both CNC & Fiber laser, laser gives perfect cutting but it has wastage..anyway considering as an option.

Use the router to cut your dies. Then stamp the coin from the die. Otherwise 4metals is right, your wasting a lot silver from the shavings.

Sounds a smart idea.

For the planchets which if you want flat perfect rounds will need to be punched out of rolled flat sheet of the correct thickness , I’m thinking at 1 mm thick a hand press should do the job it’s possible that you could include the image in the die at the same time as you punch out the coins if it’s not too detailed or high relief.

The press simply applies the force to either punch out the planchet or to punch your coins details into the planchet. So the same press can do both but requires a separate die for each. To make 20 coins the cost and machining of the dies will exceed the value of the coins. The return on investment goes up proportional to the automation built into the process.

so a 50 ton hyd press is probably enough for a fine & perfect planchet punching, what about for stamping? Is 50 tons capable of a perfectly intricate stamping on silver?

 

[Shark]

200 ton press will flatten soft aluminum from 1/4 inch to almost paper thin. I never used a 50 ton, ours jumped from 30 up to 200 ton.

 

[nickvc]

I don’t think you need such a heavy press , a simple hand press should suffice for 1mm thick material unless you intend to produce thousands of coins , you may need two sets of dies one to cut the planchets out accurately and another set for the design you intend to put on the coins.

 

[Shark]

If you only do a few at a time a large arbor press might work.

 

[Dreamer]

The minting process also involves annealing the planchet before stamping. Can anyone provide insight on why this is done?

Interesting discussion, thanks.