Duplicator Conversion

[CarveOne]

Hey, if you are going to toss it anyway, I think it would look great welded to a brake drum with one of the 1935 Ford Victoria tear drop shaped headlamp assemblies welded to the top so as to make a nifty floor lamp for the work shop. (Just kidding. That would be sacrilege of some sort for parts like that.)

CarveOne

[Fiddlemaker5224]

I have to agree, I got it at the best price. To bad I couldnt find a ball screw next to it. Found a flange that I can rethread for the ballnut mount.

I was researching rack and pinion setup today. During the research I ran across the Vee roller track and wheels that I told you about. Can't belive they are that evpensive. Been trying to find them cheaper, found some along with this.

http://www.qbcbearings.com/BuyRFQ/Li...Track_VG_U.htm#

Three different sizes. The more I look at it, I think I can make my own cheaper. If I set a metal cutoff wheel in a circular saw, set the blade to 45* then cut 1" off the leg of a 2" alumnum angle. Turn it end to end and mount it to the short leg. That will give the required 90* angle the roller needs to run on.

Now that the dreaming is over I am starting to design the conversion

[CarveOne]

I see people using skate bearings rolling against aluminum angle but I think the aluminum will not last very long if there is much weight in the gantry and z axis assembly. Ball bearings are wide enough that there is enough surface area spreading over the aluminum angle to last a reasonable time. The V rollers have less surface area on each side of the "corner" to spread the loads over much of the aluminum surface on each side. I would suggest steel angle instead, though it's somewhat more trouble to work with. If you use the aluminum angle to build the machine just figure on needing to replace it later with something harder. The aluminum will at least let you prove out your machine design while it lasts and will give you more time to find something that will last longer. Just keep an eye on how the corner is wearing and whether it is affecting the accuracy you need.

A fixed gantry, moving table design like the Rockcliff uses less parts and is somewhat less expensive to build. The moving gantry designs are more popular though. The Rockcliff design's gantry can be made more rigid if that is one of your priorities. Check out both designs and see which features you think will be best for your purposes. If your machine will only be used for violin making purposes the Rockcliff type of design may work fine for you. At least take a look at the Rockcliff forum on cnczone to see if it interests you. Most of them are made of MDF but it doesn't have to be. The JGRO and Joes 2006 designs may give you some ideas also.

You can make your own acme lead nut for that 1.5" rod from Delrin if you need to. Might be a little more tricky for one that large than for my 1/2" rods.


CarveOne

[Fiddlemaker5224]

Time sure flys by. I have been working on the fiddles trying to get them done before the holiday. Now I con work more on the conversion. I will be getting the 1/2 acme screws pretty soon.

Back to study and work


Happy new Year.

[Fiddlemaker5224]

---

Photo 0000
The aluminum arrived in the shop yesterday 1/2 x 6 x 30" (1) 1/2 x 6 x 12" (2)
Positioned and drilled the mounting holes for the rails. Tapped the hole's to 1/4-20 tpi.

Photo 0001
Upright modified to allow the extra length of the rails to extend through the upright. Drilled and tapped the mounting holes squared up the assembly and proceded with the other end of the Gantry.


Photo 0002
Assembled Grantry with Y rails in place. There is a mis-alignment of the X-rails due to the plate not being flat. I have already disassembled the gantry and will be milling the up right plate's to correct the mis-alignment.