PVC cleat to mount 4x8 PVC Panels - Questions

[Reaction GFX]

I don't do a lot of installs, but I have a client looking to mount some 4x8 panels of 12mm PVC to a concrete block interior wall. I was thinking French cleat, also made of 12mm PVC. Do you think I need a cleat top and bottom or would just a top cleat and a bottom spacer be sufficient? How, exactly, would you recommend mounting the panel side of the cleat to the panel itself, considering it is only 12mm thick? I recall using pins and some special PVC glue to bond two single-sided routered sign shapes together once to create a double-sided blank and it worked quite well, but it also wasn't very heavy and it was hung with screw eyes and s-hooks, so the glue holding the two panels together really wasn't supporting any of the weight. Maybe VHB tape instead of glue? The last thing I want is for the cleat to detach from the panels and the panels to come crashing down, potentially hurting someone.

Any advice is appreciated!

 

[Ultimate13]

We route 2 recesses 3" x 2" in the back of the panels and screw alligator picture hangers into them. Have never had one fall. The boards then sit flush with the wall creating a nice look.

We use french cleats cut out of MDF on gatorboard often and use a high temp glue gun and specific glue for that. If you do go that route, you'll need one at the bottom as a spacer from the wall.

 

[TimToad]

I would definitely use a bottom cleat also. If you have to cut cleats anyway, why not use the material to help take a little more shear off the panels?

Are you saying you can't use any screws through the faces?

If not, I'd be cutting my cleats to be about 4" x 92-94" and using several full length rows of VHB with a bead of LEXEL or Heavy Duty Construction Adhesive around the edges of your material side cleats.

 

[Reaction GFX]

I don't WANT to put any screws through the face, if it can be avoided. The only reason to only use just a top cleat and a bottom spacer is for ease of installation. That second cleat has to be perfectly placed in order to be effective. Precision when installing is not really my strong suit. (Which is why I don't personally do a lot of installs...I make the stuff, usually have another guy install it.) I thought the glue I had used previously was similar to a superglue in that it actually "melts" or "welds" the PVC pieces together to form a permanent bond, in which case I don't see the need for the bottom cleat. Will have to look it up, might have been a Weld-On product. I could be totally wrong...I do appreciate any and all input.

 

[TimToad]

I don't WANT to put any screws through the face, if it can be avoided. The only reason to only use just a top cleat and a bottom spacer is for ease of installation. That second cleat has to be perfectly placed in order to be effective. Precision when installing is not really my strong suit. (Which is why I don't personally do a lot of installs...I make the stuff, usually have another guy install it.) I thought the glue I had used previously was similar to a superglue in that it actually "melts" or "welds" the PVC pieces together to form a permanent bond, in which case I don't see the need for the bottom cleat. Will have to look it up, might have been a Weld-On product. I could be totally wrong...I do appreciate any and all input.

Is there any reason you don't want to make these out of aluminum panfaces?

I know the 12mm PVC is cheap for a substrate that thick, but with all the excess labor, materials, worry and effort involved making sure the cleats hold, you could pay for .063 aluminum, have a local sheet metal shop break all four sides for you and hang them with a couple of strips of wood or other material top and bottom attached to the wall.

We rarely ever do solid 1/2" or thicker panel wall signs any other way.

 

[Reaction GFX]

I'm not really familiar with what you mentioned. This is going to be one long, continuous timeline graphic going on a concrete block wall at a large business (laminated, digital prints applied to the 12mm PVC). Overall size will be 48" high by 232" long, and the panels will be butted up to each other, end to end. Our client received a quote from Fastsigns for 1/2" PVC, but I actually have a friend that works at the company so he called me and we're just quoting for the same thing. I hadn't really put any thought into doing it any other way, and to be honest, I don't have the time. I'm familiar with working with PVC, and I know it will work just fine. My only concern is attaching the cleat. I just found Plexus MA300 online, which is a two-part methacrylate adhesive designed for structural bonding of thermoplastic, metal and composite assemblies. They claim it will form a bond stronger than the PVC itself...something like 1000psi strength. I think that should be plenty, no? And if that top cleat is bonded that well, I don't see any reason for a bottom cleat so I'd just use a spacer.

Am I on the right track here?

 

[Billct2]

I would do two cleats, about 94" long and use PVC glue.
If you're worried about accuracy install the top one first,hang the sign and mark where the bottom one goes.

 

[rossmosh]

A single cleat on the top with a bottom spacer should be fine. 4x8x12mm PVC is not that heavy. I can handle it fairly easily by myself and I'm definitely not the strongest guy in the world. I would run a long cleat (90") or run 3 shorter cleats so that it won't warp. If you run a 5ft cleat down the middle, it wouldn't surprise me if the board started cupping a bit.

Go on Amazon and buy Gorilla PVC glue. Glue the cleat in place on the back along with your spacer. Then throw a few screws through each just to add the extra security. If you want to hide the cleat, then you can take a 1.5" wide strips and glue to the back so that it looks like a solid 1" panel which many customers appreciate and you can typically get the job done out of scrap you having lying around.

 

[Reaction GFX]

Pretty much the answer I was looking for.

I realize everyone has their way of doing things, so you're going to get a lot of perfectly good answers when asking a question on a forum like this. This seems like the simplest method to me, as it uses materials I am very familiar with. PVC cleats, Gorilla PVC Glue, perhaps a few screws from the backside is what I'll be doing. I was also kind of wondering about warpage, so I may do the top and bottom cleats just to hold the panels to the wall a bit better. That tip about trimming the edges out with scraps is a good one! I might just do that as well. Thanks!!

 

[TimToad]

I'm not really familiar with what you mentioned. This is going to be one long, continuous timeline graphic going on a concrete block wall at a large business (laminated, digital prints applied to the 12mm PVC). Overall size will be 48" high by 232" long, and the panels will be butted up to each other, end to end. Our client received a quote from Fastsigns for 1/2" PVC, but I actually have a friend that works at the company so he called me and we're just quoting for the same thing. I hadn't really put any thought into doing it any other way, and to be honest, I don't have the time. I'm familiar with working with PVC, and I know it will work just fine. My only concern is attaching the cleat. I just found Plexus MA300 online, which is a two-part methacrylate adhesive designed for structural bonding of thermoplastic, metal and composite assemblies. They claim it will form a bond stronger than the PVC itself...something like 1000psi strength. I think that should be plenty, no? And if that top cleat is bonded that well, I don't see any reason for a bottom cleat so I'd just use a spacer.

Am I on the right track here?

Yeah, you didn't mention you were butting a bunch of panels end to end. I looked up the Plexus MA300 and its like Superglue paste and the bond strength is more like 3000 psi.

Can you get a small amount and test it to make sure it doesn't melt the PVC enough to show through on the front?

 

[Patrickglamb]

I can attest that Plexus is some seriously heavy duty stuff but in this instance it seems warranted to make sure those panels stay attached to those cleats. I don't about you guys but 12mm PVC is heavy to me, guess I'm a wuss but I'd rather not be stuck by a panel falling off a wall. How are you attaching the cleats to the concrete? You're going to need a hammer drill. I watched, shaking my head, as 2 "installers" struggled for hours burning up masonry bits trying to do an install on poured concrete.

 

[Reaction GFX]

Thanks for your input...job was successfully completed long ago. Sign and cleats were made from 12mm PVC, as described. Attached cleats to back of sign panels using Weld-On 16 adhesive, which seemed strong enough on its own, but I popped a half dozen screws in each cleat just to be sure. (Screws were as long as possible without poking through the front of the sign, which still wasn't all that long.) Other half of cleat was mounted to concrete block wall with Tapcons, and of course a hammer drill was used to make starter holes in the block wall. Panels have been in place for a few months now with no issues.

Would probably do things differently if I had to do it over again. That was a lot of work making and attaching the cleats. Probably would have just Tapconned right through the sign panel to the wall (with a 12mm PVC spacer in between sign and wall) and then countersunk the screw heads and covered them with vinyl, or used some type of screw cap to cover the heads. I think I overthought this one.

 

[Marlene]

a 4' x 8' x 12mm sheet weighs about 60 pounds. I think I would use some short screws on the backside along with glue or high bond tape to make sure the cleats are secure. the screws alos might help take some of the weight