Will 3/16" foam backing do the job for this?

[Natalya Murphy]

We're working on this shadowbox of tack pieces for a customer and I'm beginning to wonder if 3/16" foam core is going to be sturdy enough to support the weight of all these metal pieces once it's put vertical. Each piece is about 3" in diameter. The heaviest one (the circle) weighs 4.4 oz. Right now the total weight of the board, fabric and all pieces is just over 4 lbs. Each piece will be held down using Jim Miller's mylar strip or medal overlay techniques. Board size is 22" x 24".

Do you think 3/16" foam core will do the trick? I'm having my doubts. Options considered:
- Use gator or mightycore instead
- keep original mount on 3/16" foam core but attach it to a rigid backing with adhesive, and possibly some screws around the edges where they wouldn't show in the final product
- mount to masonite... but how would we cut the slits for the mylar strips?

What do you think is the best way to go?

 

[blackiris]

Use the gator!!!!!!!

 

[JFeig]

The 3/16" foam board is plenty strong enough. I would cut the slots with a utility knife and expand with a painters spatula... Making sure that the tabs of the polyester film are long enough for glue down from behind with Lascaux 498.

 

[The Wavy Framer]

I would use the foam core for ease of use, then glue to a more rigid backing, probably gator.

looks like a fun project :smiley:

 

[FramerDave]

Attach a piece of mat board to the back side of the foam board. Very cost effective and you'd be surprised at how strong a mat/foam board/mat sandwich is. It doesn't add a lot of bulk to the package either.

 

[CAframer]

Many years ago, when I was learning to sail, my instructor told me that if you are ever wondering if it is time to reef, it already is.

That same logic is good advice for any type of construction project. If you are wondering if something is strong enough, don't hesitate, go ahead and reinforce; for ease of mount installation perhaps along the lines recommended by Becky & Dave.

 

[janetj1968]

I'd go with Gator.

 

[Dave]

...or adhere some polyflute board with ridges running vertically. Cheap is you are using the sign board variety.

 

[Jim Miller]

GotorFoam and Masonite are both quite nasty, chemically, but I do not know whether they would react with the metals in the closed up frame package.

I would clear-film-mount the items to 4-ply matboard and then reinforce it with glued foam center board and another matboard layer as Framer Dave suggested, or with a layer of 4 mm polyflute as Dave M. suggested.

 

[preservator]

As Jim noted, some candidated, for back boards can emit chemicals, which might interact with brass. One candidate that should not be overlooked when strength is needed, is acrylic sheet. Old pieces can be kept and reused, with a covering of board or fabric and it can be drilled and screwed into to support items, of this sort.



Hugh