Question about installing a glass platen

H

Hesparus

Joined
Oct 31, 2004
Messages
1,442
Hi Everyone!

I finally got around to buying a glass platen to put on my grizzly. The problem is that the existing platen appears to be curved away from the center by about 1/16" on both the top and the bottom. What do you think is the best way to work this out? Try to fill in the gaps with epoxy? Try to straighten it out without moving the threads out of alignment?
Thanks,
Chris
 
Use something like JB weld that has a solid filler/thickening agent to attach the glass. Spread it on your existing platen and then place the glass on it and float it around until you get good contact across the entire surface. Tape it in place on the high points rather than clamping it, to cure.

It's like bedding a rifle action or scope base.
 
Thanks! I've never used JB weld before, so I didn't know how good it was for filling in that space.
 
If you can not flaten the platen, replace it.

You can place another piece of steel on top of the old platen , then JB weld the glass on top of it.

JB weld can fill the space but it will be very hard to keep it from oozing out.
 
i milled grooves in my KMG steel platen for jb weld to have a bit of a hold spot for if you tape wrap the glass to the platen then not much should leak out if it does back fill after hard. if you have over spill its easy peasy to grind clean
 
Like has been said JB Weld works great!! I have had the same glass on my platen for nearly 4 years and there is still quite a ways to go before the grooves will be too bad to continue with it. One thing to be aware of it making the glass parallel with the belt so when you grind in your plunge lines you will have an easier time making them match. Mine is canted off just a little and it took several screwed up plunges to figure that out and grind around that issue. You also don't need a lot of pressure to hold the glass on the platen. I just used blue painters tape to hold it while the JB Weld set up.
 
try to make the base platen as flat as you can, and parallel to the belt. Use a vise, hammer and end with a granite plate + sandpaper
The glass platen will flex easily and conform to its base, so start straight!

Don't overclamp during epoxy time, the epoxy is thick and you will flex/break the glass
 
I have a Grizzly and it didn't take much to true the platen on a 6 x 48 sander. If you go the way of floating it on JB Weld, let it cure, glass side down on a flat surface. Like Butch said, tape it up to contain the epoxy.
 
Don't forget to put a ledge of some kind under the platen! You don't want it coming loose and shattering like a grenade.
 
^^^Good advice... the ledge should be affixed mechanically. Screw or bolt a ledge on... even simple studs would keep a plate from sliding down.

$_3.JPG
 
Last edited:
A woodworker I knew showed me a trick when gluing things up that works very well when I install a glass platen. Obviously, you want the platen reasonably flat before you start.
He said that using this method will guarantee all glue joints in wood or anything else will have the perfect glue line thickness.

Clean everything very well and rough up the platen surface with 50-80 grit paper.
Spread the surface with the epoxy ( JB weld works for me).
Take a piece of 30 to 50 pound test monofilament line and spiral it around the platen so the lines are about 1" apart.
Place the glass platen on the glue, moving it around as you squish out excess resin. Clamp with light to moderate pressure spring clamps.

The glass will seat down on the fishing line and squeeze out the excess epoxy, leaving an even glue joint that is about .020-.030" thick. You can't get a glue starved joint this way. When the epoxy is cured, clean off the excess, cutting/grinding away the excess fishing line.
 
Tenebr0s/Rick: Thanks for the reminder! I'm going to put a pair of bolts through the bottom.
Stacy: Great tip! I'll keep that in mind.
 
You must log in or register to reply here.
Back
Top