View Full Version : Anyone experienced with a stock duplicator?

January 25, 2013, 09:12 PM
Have a few questions on setup...

Please PM me if you would be willing to help out.


January 26, 2013, 03:13 AM

January 26, 2013, 09:12 AM
Yes. I had a Terrco.
After five years of fussing and not one decent stock I sold at a loss.
It now sets outside as a yard ornament. Thousands of dollars wasted.
Had a second one. Previous owner tried to use, gave up. I bought from him at a big loss. I traded it at another loss.
A friend has one. Has made one stock on it and now it sets outside unused.
Any more questions?
In short, those under about $5,000.00 are useless. The big industrial types do a fine job. They also do a number on yer wallet.

January 26, 2013, 11:23 AM
I've read as much.

I've also read comments from guys having reasonable success. We'll see which camp I end up in.

Back in the day, the large machines were "it"... There recently (saw it when I was shopping) a VERY LARGE, like 15 or 20- duplicator on Ebay that looked like a Terrco. Asking fifteen grand, and you'd obviously need a flatbed and forklifts or a crane to load and unload it.

But WHO in their right mind would pay anything close to that, when you can buy a 3-axis CNC today for the same dollars or less that'll blow that dinosaur away? It's almost like trying to sell a Commodore 64 computer...

CNC's, were either in their infancy, or completely outta sight for all but except the largest manufacturers.

I wasn't ready to make the investment in a CNC yet (Shop-Bot), but this might be a stepping stone.

I'm curious- you say you had no success with the Terrco- which is supposed to be the current "king" of manual duplicators.

What made you decide to try again with another machine, and what was it?

January 26, 2013, 01:30 PM
Yes used a Duplicaver for 20 years
Same machine as original bought

January 27, 2013, 01:32 PM
I'm of a mind to go the CNC route as well, altho I think a 4-axis machine is necessary. Once you have your stock blank on a spindle that can rotate under the cutter, you've attained the required cutter movement over the stock.

The challenge, IMO, in cutting on a CNC will be programming the machine to take progressively lighter cuts as you get closer to final dimension. When you're in the middle of the stock, there's substantial flexing and you have to have a light touch on the cutting pressure to avoid deflection of the stock. CNC mills don't know what "light touch" means, so you have to program it in.

BTW - making a stock duplicator shouldn't be difficult. The big units are just made with some I-beams of steel for the base, then some round linear ways for the pantograph upper. There's no rocket science involved anywhere on the machine.

January 31, 2013, 01:34 PM
Call Dave Keck at Knob Mountain Muzzleloaders in Berwick PA.

sent from my S III using TapaTalk

4V50 Gary
February 1, 2013, 08:14 AM
Yesterday at school we were shown some basics about the duplicator. Our teacher showed us how much wood flexes under pressure. That can ruin a blank if the operator is not careful.

There are NRA summer classes at Trinidad that teach Inletting and stock making at Trinidad State. Sign up before the classes fill up.

February 1, 2013, 09:55 AM
What made you decide to try again with another machine, and what was it?

The second one came available at a couldn't refuse price before the first was assembled. I later learned why it was sold so cheaply.

February 1, 2013, 04:17 PM
Anyone who is interested in duplicating stocks should have a look at how a Dakota duplicator is made.

They're hardly rocket science. The supporting frame is basic ironworking (drilling, bolting, welding) and them for true bearing surfaces of the pantograph, they use round linear ways. If you don't know what a "linear way" is, google them and learn how modern machines ways are made. Hint: CNC machines don't use prismatic ways any more.

All that is necessary and remotely complicated are the bearings and assembly of the pantograph head.

I'd reckon that one could assemble one for less than $4K in iron, aluminum, fasteners and linear ways. Last I looked, the price of the Dakota dupe machine was over $10K.