CNC Retrofit A Heath/Torchmate Upright Magnetic Follower Shape Cutter

[Weldtutor]

Has anyone done a CNC retrofit on a Heath, Torchmate, or other upright shape cutting machine?

This style was popular 30-40 years ago for oxy-acetylene flame cutting.
A motorized magnetic spindle followed a steel pattern.

It would seem there are several approaches to a CNC conversion of a unit of this design.
Ideas & discussion encouraged.

As an aside, if anyone has an old motorized mag spindle, or plans for it, please PM me.

[blackhollowmfg]

Old?? LOL, we still run two of them here in the shop! Old green Japanese made things, but they still work great! I do know that Torchmate sells plans to build their machine on eBay for $40.

[jcc3inc]

Sir,

Several years ago I did a retrofit on an Airco Travograph machine which originally used a mag follower. At that time we made optical line tracers using rack and pinion drive for both axes. Thus it could have been CNC instead. (The Travograph was not an X-Y machine, but rather it was a combination of polar and Y motions, a little like what I think you are refering to!)

We made an X-Y carriage which ran on their tracing table. This carriage was triangular shaped with the X axis about 1/2 the Y axis length. A drive motor on the X used rack and pinion to propel the carriage. On the carriage, there was a set of ways for the cross axis and a small motorized cross carriage was connected to the torch bar for the Airco machine. This added carriage effectively converted the machine to X-Y.

We did many retrofits of rack and pinion drives to all sorts of cutting machines
and all were rack and pinion drives. 94% of them were X-Y machines.

Regards,
Jack C.

[Weldtutor]

Originally Posted by jcc3inc Airco (Travograph was not an X-Y machine, but rather it was a combination of polar and Y motions, a little like what I think you are refering to)

It sounds similar Jack, and a very satisfactory modification you did.

The Heath "Ultragraph" series of upright shape cutters had 2 linked arms to cover a circular work space, and were available either wall mounted or free standing. (Heath was taken over by Esab)

I was thinking of a CNC conversion that maintained the arms, rather than building a gantry.

[millman52]

Originally Posted by Weldtutor It sounds similar Jack, and a very satisfactory modification you did. The Heath "Ultragraph" series of upright shape cutters had 2 linked arms to cover a circular work space, and were available either wall mounted or free standing. (Heath was taken over by Esab) I was thinking of a CNC conversion that maintained the arms, rather than building a gantry.

Like this Linde branded one I am still using? See my hard drive with my CAD/CAM files hanging on the pegboard in the background. In this case mine is bolted directly to the burning table for more stability. Control box is very basic. I added a solenoid on the pierce line to make that a bit easier to deal with. mounted the controls to a moveable pedistal & converted the control box boom to a jib arm to allow hoses to move more freely with the torch travel. You really can't get a more accurate cut than one of these things will do. They will cut the same exact part time after time. Just spend loads of time making & then perfecting the templates.
second photo downloaded from ESAB's Website

Actually seen one of these recently sell on EBAY, in the Washington state area, for somewhere just over $1000.00

[Weldtutor]

Originally Posted by millman52 See my hard drive with my CAD files hanging on the pegboard in the background. Just spend loads of time making & then perfecting the templates.

That's the style machine.

I was thinking each of the two main joints could be CNC'd by a nut & ball screw or acme screw, with some limitations on area covered. A motor with timing pullies/belts at each joint would cover a greater area although possibly be somewhat more challenging to build.

Is that about a 100 pound "hard drive" with the CAD (Customer Approved Designs) loaded there?
= Beautiful story
Your CNC machine is almost done!

[millman52]

Originally Posted by Weldtutor That's the style machine. I was thinking each of the two main joints could be CNC'd by a nut & ball screw or acme screw, with some limitations on area covered. A motor with timing pullies/belts at each joint would cover a greater area although possibly be somewhat more challenging to build. Is that about a 100 pound "hard drive" with the CAD (Customer Approved Designs) loaded there? = Beautiful story Your CNC machine is almost done!

It seems to me that somehow in your CAD/CAM software you would have to show your stock being cut as round. either that or calculate how much of a rectangle/square the radigraph arms will cover. Then place any stock to be cut inside that area.

[Weldtutor]

Originally Posted by millman52 calculate how much of a rectangle/square the radigraph arms will cover. Then place any stock to be cut inside that area.

I think as you suggest in the quote above would do it.

Other CNC'd mechanical drives, properly designed and executed, would likely allow full coverage of the original work envelope.

(Your CAD/CAM files in the picture sure would take a lot of "Filing")

[millman52]

also would probably have to somehow stabalize the pipe mast the arms are mounted to. There is quite a bit of bounce/spring in mine. The additional weight of motors, ball screws etc. I'm sure would make that even worse & most likely droop as the arms reach farther out to maximum reach.

But after reading your post(s) I think it would be doable. I bought the one I have complete with 3 line torch & 3 regulators & hose for $350.00 I scrapped the "duck feet" leggs that it was attached to. Built the small burning table & mounted the machine directly to the table.