New guy here. Don't do rocks or glass, but my wife does. She recently bought an old Glastar G-3 that looked identical to jerrysg's above in Reply #4 above. She, too, wanted it to look "more modern", so I started looking into it and found this thread. I liked the outcome shown in Reply #10, but there were a few details missing on how it was accomplished.
Not sure I can mention vendors, but seeing the practice already used in this thread, I'll mention that I got a Glastar replacement top plate for a G7 - G12 - G14, p/n 30750, from Rocky Mountain Glass Crafts in Loveland, Colorado. Lots of places likely sell this part, and there is absolutely no endorsement implied here.
I modified the G-3's original plastic somewhat to accommodate the replacement top, not the other way around (with one VERY minor exception). This is so another replacement top can be fitted with the most minimal modification (trimming some pins), as explained below.
To begin, I found that two of the back-side "pins" on the replacement top exactly lined up with two of the old screw towers. However, the towers were threaded, and the pins needed to slide down into non-threaded holes. The pins are 1/8 inch in diameter, so a drill of that size was selected. Note the blue tape on the drill. That is to prevent it from drilling any deeper than necessary. I wanted to make sure that I did not drill all the way through into the motor chamber, as I don't want the possibility of water getting to the motor.
Since the holes are now only about 5/8 of an inch deep, the pins that will fit into them will need to be no longer than that. The length of the pins will be determined by how deep you make the holes. The third pin is trimmed to clear a small plastic riser in the tray. That pin could be cut completely off if desired, as it really doesn't do anything.
Next thing to get trimmed was the sponge surround "fence". Since the new top also has a fence, and they are both at the same position relative to the cylinder, they interfered with one another.
Again, I trimmed the original fence down to about 1/4 inch high so another replacement top's fence won't have to be trimmed. My plastic was cut down with the use of a Dremel, but I'll leave that for you to determine how. You will not be creating a water leak by trimming this, but leave a little height to the original fence. Be sure to tape up the motor shaft so plastic dust doesn't get down in the motor's bearing.
The new top's dimensions leave a gap at the front so you can determine the water level.
Note that the splash guard is made of a "rubber" material, and flexes out of the way easily.
Also note that this new top will accommodate Glastar's plastic eye shield.
Hope my first post here is able to help someone in the future. Isn't that what the forums are for?
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