stopping gaps between sheets ?

[Andy Gorman]

You should be using locks on the panels. They are plastic hooks that are hidden inside the frame, glued to each panel and hooked to each other. I THINK they are called panalocks. I buy them from the place where I get my framing material from. Once installed the whole sign can expand and contract naturally without the panels separating.

I assume you will rout a rebate on the panels so that they interlock, this helps to hide any small discrepancies where the panels butt.

The only way I can think of to prevent the wind getting behind the sign and rattling it about is to fix a backboard to the frame. Big frame though!

Oh yes, welcome to the board. 😀

[elitesigns]

Is the sign going to be the full 4′ high ??

If so i would never use foamex for a sign of this size, you are asking for panel blowouts.
Its worth getting a copy of BS559 this will help you material chose for sign panels etc.

Another point to remember is that the panels are usually sucked out from the front

[Robert Lambie]

Hi mate big welcome to the site.
With a sign this size made from this material you could have a bit of bother.
I wouldn’t say so much the gaps opening, more a blow out/suck out of the middle sheets.
Foamex bends easily so if at the back the wind is pushing out the middle of the foam will belly and may pop the sheet out altogether.
You have gold access, so I would advise having a look at my panatrim demo for the frame work. A trim sign of this size can be erected pretty easy without constructing it the way I have but you want to make the trim as snug a fit as possible. If the foam is 48 inch deep make the trim 48.5 deep.
Check the part about hanging brackets also. This is just scrap strips stuck along the edge of the foam. I would suggest a hanging strip along the top and the bottom. This should prevent the sheet being sucked right out, but I cant promise it wont.
On the joins it’s a hard one. There are many ways to join sheets. The problem with foamex is it expands and contracts. Ill have a think and see what I can come up with..
If im honest I would have to say, “try use a different material” I know the cost is going to be more but if you haven’t given a final quote I would try for something more rigid. 🙄

[Andy Gorman]

Good point (elitesigns). I’ve heard of people putting hanging strips both top and bottom of signs in frames. I suppose this would prevent blowouts as you call them. I’ve never done it personally. I reckon you would have to be very accurate with the positioning of the hanging strips so that it would slide into the frame nicely.

[-steve]

Yeh the sign is going to be the whole 4ft high. Any suggestions on what material to use then? perspex, dibond??

Those Panalocks sound interesting, anyone any contact no’s for a supplier?

I was going to route a rebate between the joins, and i’ll try the top and bottom hanging strip.

Thanks guys 🙂

[Nigel Fraser]

Welcome steve, Some good point above and I would echo the material choice is not ideal. I would go for 4mm dibond/reynobond for this sort of size panel sign, I pay £65 for 2500x1250mm sheets, so its a fair bit more than 5mm foam but about 100 times better rigidity and expansion !

If you have to use foam, i would consider using either a thicker sheet 8-10mm or at the least 5mm gloss finish which is a fair bit more rigid with top and bottom hanging strips. The bottom can be a bit “loose” to allow for tolerence when sliding in the panels. I personally dont like panalocks much and tend to use a rebated joint with a 3 or 4″ strip of material stuck along the length of the joint at the back of the panels. This stops the rebate opening up in one direction and you can put a couple of small screws with caps through the face to lock the panels together if you like.

Dont forget you will need a resonable gap for expansion at the ends of the frame if you use the foam option – Ive seen several frames where the panels have pushed the ends off through expansion (obviously not well enough screwed together!)

I think you can get panalocks from cherwell sign supplies (used to do them?) on 01280 840297.

Hope that helps,

Nigel

[Gazza]

Hi Nigel, who do you get the Dibond at that price from? my local supplier wants just over £100 & vat for the same?

Regards
Gaz

[Nigel Fraser]

Gazza, Cox Plastics – though I saw their rep and negotiated some special prices on all the stuff I use most. Having said that, I only buy small quantities (maybe 10-15sheets a year?) of this so I guess most people on the boards could have a go at pressing their supplier to get a better deal if needed ! Amari plastics charge me around £70 for the same thing I think.

Good luck 😉

Nigel

[Gazza]

Thanks Nigel, appreciated mate, I will give them a call as i still have to sort out suppliers and obviously don’t want to waste cash during the startup period hence the request for supplier info. 🙂

Gaz

[Alex Wilson]

If you must use foamex then cut some 2″ strips 4 ” smaller than the height of your sheet and glue them to the back vertically every foot or so to stiffen up the foamex and hopefilly stop the suck out effect