How To Level A Glass Top?

[Dick Pacini]

Somewhere, I read an article about leveling a glass bench top with playing cards, razor blades and string.  It also had pix which showed the procedure.  I thought it was written by Bob Hunt and have gone back and found his bench articles in MA, but nothing about a glass top.  My glass bench top has an airgap under it and I need to true it up.

Does anybody remember where that article appeared?

[kenneth cook]

                 The key to building on the table is straight. The glass doesn't necessarily have to be level. Obviously you don't want the table leaning out of level to the point that a pencil rolls off. The more true you can shim the substrate before the glass, the better and easier it will be to getting the glass straight.  Once your substrate is close then you could glue 1/4" nuts to the glass in each corner with ca(all nuts the same) and use a piece of thread on top of them keeping the thread tight. Check with a loose nut every few inches under the line. This will reveal if the top is crowned or hollowed. This can also be done with a good straight edge. From corner to corner stringing the thread from nut to nut you can check for a twist. The strings should just kiss each other at the intersection. Shimming accordingly under the glass if need be. We use lasers at work but this works just as good and we use the thread from corner to corner to check to see if door frames are aligned properly. While checking the nut under the string you can see how many shims are required to raise the glass. Make a note right on the glass with a Sharpie this way you know how many shims are required. Ken

[Tim Wescott]

But, straight and level means that you can set up parts using a machinist's level as a reference.

[Larry Cunningham]

I have a 3/8" thick glass sheet, and I'm not convinced that it needs any "leveling". Over its ~6' length, how far out of true flat can it be? (Yes, I am aware that sheet glass is really a liquid and flows out {over centuries}..)

Getting it to sit well on a {typical} wooden table top lacking such flatness may be harder if you are trying to do it by shimming the glass sheet. But your local hardware store has inexpensive soft plastic buttons which comply enough to interface a thick glass sheet and table top and prevent it from mucking about.

Failing that, accept the lack of flatitude of your 60" stunt wing, which came out with a 10 mil high/low spot from that crooked glass sheet. It's an imperfect world.  ;->

L.

"If you wait until the last minute, then it only takes a minute." -someone in Mr. Deckert's (whose??) senior Design Class

[Wynn Robins]

But, straight and level means that you can set up parts using a machinist's level as a reference.

relative to the surface

[proparc]

Windy Urtnowski has the procedure on video whereby,(I have it), he levels his glass top using playing cards prior to construction of one of his ships. He also, goes into detail as to how build VERY accurately on that same top.

[RandySmith]

I have a 3/8" thick glass sheet, and I'm not convinced that it needs any "leveling". Over its ~6' length, how far out of true flat can it be? (Yes, I am aware that sheet glass is really a liquid and flows out {over centuries}..)


No No Larry  it is more like ice and it melts after many centuries   

Randy

[Dick Pacini]

Well, I got it pretty level using baseball cards under it in several places.  I wasn't so concerned with it being dead nuts level, but the fact that it wasn't sitting flat on the bench top because the bench top wasn't perfectly flat.  There were unsupported gaps under the glass in spots and the glass would deflect if I put pressure on it.

Close only counts in horseshoes and hand grenades.

[builditright]

Dick, you can get these at your local Home Depot or Lowes store or similar type store

they are small rubber bumpers that go under the glass top.
Buy a bunch of them and place them every few inches apart in a straight line
they have a sticky back to them so they will stay where you put them.   

[Dick Pacini]

Dick, you can get these at your local Home Depot or Lowes store or similar type store

they are small rubber bumpers that go under the glass top.
Buy a bunch of them and place them every few inches apart in a straight line
they have a sticky back to them so they will stay where you put them.   

Yes Walter, those are good but if the bench top has high and low spots on it, the glass will still be unsupported in spots.  I'll try it and see if I can locate them all on the same plane.

[builditright]

Yes Walter, those are good but if the bench top has high and low spots on it, the glass will still be unsupported in spots.  I'll try it and see if I can locate them all on the same plane.

Thats probably true, then maybe you may want to fix the bench so it is flat or replace the top then these will work for you or you can place them in various spots to help assist you in compensating for the high and low spots.

I remember having a similar issue with an old bench so I had a friend build me a new one.

This is the new one shown below and it even has wheels so it can be moved around.

[jim ivey]

autocolumator

[john e. holliday]

If you have a great straight edge you can level the top of the bench the glass will llay on.   Go to one of the home supply stores and look for a material that you put down to level floors.   It is a paste that is put down before the subflooring of linoleum.   If you have ever laid a cement drive or walk, you do this the same way.  Real nice straight edges on each side of bench top.  Pour on the paste and drag a straight edge down the two straight edges you have attached to the bench.   Don't forget a little trowel to fill low spots as you go.  Of course have a good solid top to do this to.