Dry Wall Anchors for foam walls - Test completed !

[Fred Trout]

Has anyone tried out anchoring the foam walls using something like these fasteners -- especially to prevent Gorilla Glue from moving the wall ??

http://www.amazon.com/TOGGLER-SnapSkru-Self-Drilling-Drywall-Anchor/dp/B0051IB63Q/ref=sr_1_cc_2?s=aps&ie=UTF8

[GPW]

Not that we know of ... You’ll be the first to tell, us how they work Fred !!! Since foam is "different” , you may want to try a pilot hole ...

[Fred Trout]

An experiment is definitely in order. Gotta check if the screw explodes the foam when fully installed or if it holds worth a fig at all. I was thinking of using them for alignment and holding the wall in place while the glue cures, so only a few would be needed.

Yeah, gotta drill a pilot hole for both the OSB and foam in oneshot for sure to do the assembly & get it lined up. You would need to drive the plastic screw into the foam. Then frantic running around to apply the GG, line up the holes, drive the screws in from the bottom of the OSB to hold it all together. Should be quite a trick, hehe.

Will post back when I try it out.

[Fred Trout]

Just tried some Walmart cheapo dry wall anchors with 1" foam scraps. It certainly worked well enough to hold the foam in place while glue was setting up. I have a vertical Gorilla glued in piece curing now but there is little doubt that the screws would hold the wall in place with the foaming action. They make these anchors is all sizes and lengths so they should be good enough for setting walls up. They are pretty sticky at first and you should pre-tighten a screw into the nylon body before mounting it in the foam. Sequence is

1) drill pilot hole for assembly but mostly so the steel screw goes thru the floor easily and aligned
2) place nylon body into foam pilot hole separately
3) place screw partway thru into floor so that the tip slips into the nylon body (which has been pre-fitted with screw)
4) apply GG or other glue
5) align wall and screw steel screw into nylon body as tight as desired

Will add results pix of GG stress test after it has a chance to dry. I only used a few GG drops for this test - may have to redo the glue-up with more, never used GG before.

[Fred Trout]

Second glue-up with much more GG - note the GG coming out in the side between the pieces of foam

One screw was able to keep the foam in place, so dry wall anchors likely work for that use. I plan to remove the screws before canvas covers the underside of the floor.

[GPW]

Nice test Fred !!! Thanks !!!

[Fred Trout]

Welcome, GPW.

Foam GG allowed to cure overnight. First "wall" with drywall screw left in place could not be lifted straight up but I am a 100 lb weaking. Lateral force failed about as you would expect. Note the amount of foam sticking to the wood. The dry wall screw left in place probably did not contribute much to the lateral resistance since the foam is the weakest link.

The second piece of foam with a good amount of GG broke off also as expected but note that the expanding foam expressed along the edges acts as an additional glue surface and caused more foam to adhere. That was a surprise & the moral of the story is apply enough GG to get a 'sticking bead' along the edge for extra strength.