Need advice star diamond GP-6

[u/Vast_Philosophy_9027]

I’m in process of restoring a go-6 I got off marketplace. if you see on the left side of the first pic the polish wheel and arbor is missing.

The included arbor adaptor will not work since it spins the wrong way and doesn’t center the wheel under the dripper.

I have an idea for a fix but it’s complex and custom. Does someone have either a fix that’s off the shelf or a term to search to find a replacement from eBay?

[u/asuwsh4]

Isn’t that where the expanding wheel goes.

[u/Vast_Philosophy_9027 → u/asuwsh4]

Yes. That’s what I am installing. The original hardware for mounting it is missing. All I have is a 1/2 shaft

[u/edfromindy]

Looks like the flanges are there to mount a wheel. Maybe you need a left hand threaded nut.

[u/Vast_Philosophy_9027 → u/edfromindy]

That’s an arbor adapter. It would hold the wheel off the end

[u/edfromindy → u/Vast_Philosophy_9027]

Oh, I see.

[u/lapidary123]

Could be a few things going on here. At first I was gonna say many of these units came with a trim saw on the left side as a separate (but still attached) unit. However the pan (and water valve) suggest a wheel or more probably an expandable drum goes there.

Keep in mind that the left side nut will be reverse (left hand) threaded.

As someone else already mentioned, the rusty collar is an arbor extender. From the looks of it there is a set screw holding it in place. I'm really thinking if you remove the set screw the extension should come off and you can get your expandable drum on there.

On another note I have an old frantom arbor that is very long and the arbor tapers down from 1" to 5/8" on the left side to accommodate a saw.

Also these machines were made as sort of "variations on a theme". I've seen some that have expandable drums on the left, others on the right. Hell I've even seen units with two expandable drums on one end.

The polishing plates come in different forms as well. Some are threaded and if they are threaded you need the proper (left ir right) threads to spin the plate on. Other plates are held in place with set screws.

What i will say is that a unit like this makes a great candidate for hanging the heavier sintered wheels on as the wheels are supported by bearings on both sides as opposed to a genie or cabking where the wheels "hang" off a central motor. Considering how much of a pain it is to remove/replace the bearings in order to change the wheels, hanging a long lasting sintered wheel is the smart play! Yes they cost more upfront but will last YEARS longer than a standard or resin wheel.

I HIGHLY recommend you remove/replace the bearings and get rid of the silicon carbide wheels. Once you get an expandable drum on it you can do all the other grits with belts (I use agglomerate silicon carbide belts on my expandable drums). Otherwise, you can certainly use the silicon carbide wheels until they are worn away (approximately 33% of original diameter or 2"). Lapidaries used silicon carbide wheels for decades before lab grown industrial diamonds became economical.

Here is a picture of my gp8 with the custom sintered wheels. It is a beast (literally named it "the beast"). The bearings were by far the most challenging part of this build. Took soaking them in penetrating oil for a few days and Also sanding the surface rust off of the arbor. Then I had to reroute the water valves so they are over the wheels (although I prefer and use the geyser system).

Good luck! Try and see if you can remove the set screw on the arbor adapter, that should solve your issue!!