Standalone Indexer Build

[br928]

After several years of collecting various ShopBot components I finally decided to build a standalone indexer.

A couple of months ago I bought rails off the forum from a botter that was upgrading from 4' to and 8'. Getting the extruded aluminum, hardened rails and racks was the last thing I needed to start this project. I already had a 4G board, motors, indexer and a Z axis assembly.

In this design I will use one of the extruded rails as the base for the indexer. I mounted the hardened rail assemblies to opposite sides of one extruded aluminum rail.

A plate was cut that will be the bottom of the gantry carriage. Four Dual Vee wheels are mounted to this plate. Two of them are fixed and two are adjustable. That way the preloading of the wheels to the hardened vee rail can be set.

This plate also holds the stepper motor that will drive the gantry. Because this design makes reaching the motor mounting bolts difficult, a separate motor plate was cut. This way the pinion engagement can easily be adjusted.

The second extruded rail will be cut in sections that will make up the rest of the gantry. Two vertical and one horizontal cross piece. The Z axis will then bolt to top cross section.

These are some pictures of what I have done so far. Keep in mind these are views of the bottom of the gantry plate. The indexer will mount to the other side.

[dougo]

Looking forward for your updates.

Thanks

[br928]

I received the gussets, brackets and joining plates today. This is what the top part of the gantry looks like.

[myxpykalix]

Stan,
This looks like a neat project and well put together. What is the max width and length you will be doing with this?
Will you be using the regular control software to run your indexer?
keep the updates coming

[br928]

Jack,

I am using a standard ShopBot indexer. The capacity is about a 5" radius. 6" if you jump through hoops. Length capacity should be 4-5 feet.

Control will be a 4G board w/ Gecko G201Xs and SB control software.

[Brady Watson]

Looks great so far, Stan. I'd recommend 4 more v-roller bearings on that Z. It will really stiffen it up & make that t-rail last a lot longer.

-B

[fozzyber]

Can you expand on this? Why and results, experiences....

Looks great so far, Stan. I'd recommend 4 more v-roller bearings on that Z. It will really stiffen it up & make that t-rail last a lot longer.

-B

[Brady Watson]

Jerry,
Early PRTs were shipped with 4 v-rollers on the Z. This was fine for most lightweight routers and for people cutting mostly 2D where there wasn't a lot of Z movement in the file. As heavier spindles became more popular and access to 3D files became easier for the masses to cut, the t-rail got a lot more action than it used to. 4 rollers barely support all that weight. 8 really does a much better job of distributing the forces of cutting from the spindle and the rest of the machine.

I'm on my 3rd t-rail after hundreds of thousands of parts...the 4 additional rollers drastically extend the life of the t-rail. The rails then to wear in the spot that you use most frequently - 4 more rollers spreads this load out a bit so that you don't go from tight in one spot to loose in another spot. For some of you, your z tower already has provisions for 4 more rollers. Those who do not, will have to drill some 1/4" holes.

-B

[br928]

New mounting holes in the T-Rail had to be machined for the 1 1/2" spacing of the extruded aluminum.

[br928]

PC router, headstock and tailstock mounted.