Help on gluing plexi to wood

[chascp84]

Hey guys need some opinions on bonding plexi to plywood. I am in the process of making a staircase liquor display for my little liquor cabinet and am hesitent to glue the plexi because i'm afraid of messing it up. My main concern is the glue showing through the top of the plexi. What products can I use to bond these two together?

 

[cowboy73]

I wouldn't use any glue on the plexiglass. It's going to show. I would find some little strips of metal, stainless steel, copper, brass, etc. and drill holes in the ends of the plexiglass and fasten the metal strips on the ends. Kinda like in my poor paint illustration. You won't loose too much of the shelf space and it would look pretty good if the metal is polished up.

 

[pattenp]

It you are using the plexi as a laminate then I think you're going to be hard pressed to find something to glue it to the wood without it being visible through the plexi. You could try a sample with some scrap pieces using spray contact adhesive.

Edit: I think a mechanical method suggested by cowboy is the way to go.

 

[c_mccann]

there is plexi-glass glue, totally clear. Google it or call a plastics place and they can tell you the product name. I've used it before with great success

 

[PA-Buckeye]

If you're using clear plex, then there's not much you can do other than the mechanical methods already mentioned. You could also go with finish washers as well.

Unless you fabricate the plex as one unit to fit over the plywood. In that case, you'll want to use the acrylic solvent that c mccann mentioned. Weld-On makes a couple of types for joining acrylic/plex edges.

If you're using a solid color plex, you can use contact cement to bond the two surfaces together. I've done it numerous times and it works very well.

 

[L5wolvesf]

I've heard 3M has a good tech line for such things.

L

 

[chascp84]

I wouldn't use any glue on the plexiglass. It's going to show. I would find some little strips of metal, stainless steel, copper, brass, etc. and drill holes in the ends of the plexiglass and fasten the metal strips on the ends. Kinda like in my poor paint illustration. You won't loose too much of the shelf space and it would look pretty good if the metal is polished up.

Thanks for the illustration, but I wanted to keep the surface of the plexi flush with the wood. I think if i slipped some strips of metal it would raise it too high.

It you are using the plexi as a laminate then I think you're going to be hard pressed to find something to glue it to the wood without it being visible through the plexi. You could try a sample with some scrap pieces using spray contact adhesive.

Sorry I did not mention that I blasted the plexi to give it a frosted look. I think if I sand it down a little more the glue (if clear) would be faint.

there is plexi-glass glue, totally clear. Google it or call a plastics place and they can tell you the product name. I've used it before with great success

I think i have used this product before, if its the stuff that is applied by syringe. I thought this only works if fusing plexi to plexi almost like PVC pipe glue. I bought this stuff from the companyI got the scrap plexi from.

If you're using clear plex, then there's not much you can do other than the mechanical methods already mentioned. You could also go with finish washers as well.

Unless you fabricate the plex as one unit to fit over the plywood. In that case, you'll want to use the acrylic solvent that c mccann mentioned. Weld-On makes a couple of types for joining acrylic/plex edges.

If you're using a solid color plex, you can use contact cement to bond the two surfaces together. I've done it numerous times and it works very well.

Yes I am using clear plexi sanded to give frosted look. The plexi is one piece that sets on top of the plywood. I will have to try a scrap piece with the weld on and see if it will make contact on the wood side.

Thanks for all your input guys!

 

[chascp84]

I've heard 3M has a good tech line for such things.

L

I was thinking of doing some double sided tape from 3M.

 

[PA-Buckeye]

Oops! Sorry to give you the wrong idea. The Weld-On solvent is only used to join the sheets of plex together.

It won't do anything for plex-to-wood bonding except muck up your plex.

 

[Greatbear]

I'd use some small brass round-head brads on each corner. Predrill the plexi for clearance, and predrill the wood for a snug fit. You'll be able to remove the plexi in that inevitable case where liquid spillage gets between the plexi and the wood, clean things up, then replace the plexi by tapping the brads back in.

 

[crazytrain]

I'd use some small brass round-head brads on each corner. Predrill the plexi for clearance, and predrill the wood for a snug fit. You'll be able to remove the plexi in that inevitable case where liquid spillage gets between the plexi and the wood, clean things up, then replace the plexi by tapping the brads back in.

X1 for this or some small flat head screws counter sunk into the plexi.

 

[AffableCurmudgeon]

I would rout out the wood the depth of the plexi leaving a 1/8 of an inch lip around the perimeter and inlay the plexi. The lip will keep it from sliding. You won't see the edges of the plexi either.

 

[pcmeiners]

Skip the Plexi, get tempered glass cut (beveled/edge sanded/polished), Plexi will scratch or at least scuff over time. I have seen a light bronzed colored tempered which would match the wood tone

 

[dipper]

try some GE clear silicone caulk or polyseamseal clear adhesive caulk.
Both should be available at your local box store.

 

[SlappyWhite]

Come up with a way to mechanically fasten it instead of glue. Even with the frosting glue will likely show through. Solutions could be:

Keep the sides a little taller than the step and have the plexy slide into a dado on the sides and back.
OR use some aluminum or wood trim on top of the plexy and fasten through it to the wood underneath, maybe just at the sides.
OR Countersink some stainless fasteners (screws) through the plexy and make them look a little decorative.
OR have the back of each shelf start above the plexy, have the plexy run underneath it and fasten from the bottom up only at the back of each shelf (this would work well with the dado BTW).

If you are dead set on adhesive:

One solution I can suggest is a good clear epoxy and make sure that you have 100% coverage and no overages, that way even if it shows through it will be a consistent finish.

 

[Steevo]

Too late. While you were farting around making a shelf, I drank all your booze . . . .

 

[chascp84]

Too late. While you were farting around making a shelf, I drank all your booze . . . .

Thanks Steevo, I guess I will have to lock it up next time!

 

[chascp84]

Come up with a way to mechanically fasten it instead of glue. Even with the frosting glue will likely show through. Solutions could be:

Keep the sides a little taller than the step and have the plexy slide into a dado on the sides and back.
OR use some aluminum or wood trim on top of the plexy and fasten through it to the wood underneath, maybe just at the sides.
OR Countersink some stainless fasteners (screws) through the plexy and make them look a little decorative.
OR have the back of each shelf start above the plexy, have the plexy run underneath it and fasten from the bottom up only at the back of each shelf (this would work well with the dado BTW).

If you are dead set on adhesive:

One solution I can suggest is a good clear epoxy and make sure that you have 100% coverage and no overages, that way even if it shows through it will be a consistent finish.

All you guys had great ideas, but I dont think they would work for the look i am going for. The plexi will be illuminated by led from within the frame so the clean look without any fasteners is ideal. This picture was my original design were the plexi was inlayed into the wood. I found this to be to hard to match the cut of the plexi to the wood leaving gaps. I ripped this with a circular saw, wish i had a router.

Here is an aerial view of the framing. Afraid of fasteners splitting the plywood layers.

Here is my current solution, L shaped wood trim. I will glue the top part to the plexi and use a finishing nail to attach it to the frame.

Many thanks for all the replies!

 

[PA-Buckeye]

Ooooooohhhh.......(smacks head) that's what you're doing. I thought you wanted to cover the verticle surfaces as well, basically making a small set of stairsteps out of plex.

Pics when it's all lit up or it didn't happen!

 

[Zeke]

For future reference, Plexi to wood is accomplished with a thickened version of the welding solution, i.e., model airplane glue. It would have showed on your project. Having some type of cap or an opaque strip to hide the plywood edge was a good move.

You could have also made the step structure sides and faces out of solid white, colored or black Plexi and glued it all together with the seam glue. The illumination of the top pieces would have had an infinite effect like looking at the edge of a piece of glass that has been polished.

Cool project. That would be neat for any kind of display.

On that I would have had the top overlap the base.

 

[chascp84]

Ooooooohhhh.......(smacks head) that's what you're doing. I thought you wanted to cover the verticle surfaces as well, basically making a small set of stairsteps out of plex.

Pics when it's all lit up or it didn't happen![/QUOTE

Sorry guys, i should have explained it better before i started throwing pictures at ya!

 

[chascp84]

For future reference, Plexi to wood is accomplished with a thickened version of the welding solution, i.e., model airplane glue. It would have showed on your project. Having some type of cap or an opaque strip to hide the plywood edge was a good move.

You could have also made the step structure sides and faces out of solid white, colored or black Plexi and glued it all together with the seam glue. The illumination of the top pieces would have had an infinite effect like looking at the edge of a piece of glass that has been polished.

Cool project. That would be neat for any kind of display.

On that I would have had the top overlap the base.

Full plexi was my first setup, but i ran the process through my head and backed out. I was worried if i did all plexi my seams would not match because of the use of a table saw to rip the plexi to size. Secondly i chose not to because i didnt know how hard it would be to hold the seems at 90's and fuse it with the weld on. Third i got lazy and didnt want to think about a way to black out each step to make them each their own colors. Wood frame made it simple with wood glue and brad nailer. Wood frame also keeps light separated to each step.


Buckeye, no lights yet as i have a million other projects goin on like most of us on here. As soon as i get some i will post. Thanks

 

[Zeke]

Best blade on your saw is a diamond plastic cutting blade. Leaves an edge ready to glue. The glue melts the plastic together forming a crystal clear joint.

 

[chascp84]

Ooooooohhhh.......(smacks head) that's what you're doing. I thought you wanted to cover the verticle surfaces as well, basically making a small set of stairsteps out of plex.

Pics when it's all lit up or it didn't happen!

Per Buckeye's request, haven't had time to upload. There are still some finishing touches need to be done but you guys get the idea. I will try to get some better pics of it later. Thanks for all the comments and ideas for this project. Now I need to stop drinking the booze so it can sit on the display!

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