Just a sanity check here. I got two pieces of 1.5" pink foam from HD. Last night I spread some Elmer's yellow carpenter's glue on the lip/edge and put some weights on the joint. 24 hours later I picked it up and it split down the middle. At first I though the glue joint failed but low and behold, the glue was still wet!!! I realize that foam is pretty air tight so how long should I let it sit before cutting/handling? 2-3 days? A week? A couple of weeks? A month?
Well, it's a little late for LN as it'll be a chore to wash off all that glue (plus the weather is not exactly warm yet). Are you saying that LN is the only thing that works with pink foam? I thought I read in various forums that white/yellow glue works too but they never said that it would take longer to dry. I know people use white/yellow glue to lay down cork bedding. Yes, cork is a bit porus than pink foam so it should dry faster.
yellow/white glue wil stick to almost anything, just has a longer cure time. when working with pink/blue foam i use adhesives for polystyrene such as: liquid nails for projects i also use a spray adhesive: sta'-put II for polystyrene foam (for industrial use only) obtain this from local recreational vehicle dealer. tell 'em it's in the STAG catalog. 3m also makes a spray adhesive for polystyrene. do not use "garden variety" spray mount as it is "temporary" hold hope this info helps david
Thank you David and the others for the info. Well, I went down to the basement this afternoon and it's too late for LN. Some of the glue has dried, starting from the ends and working toward the middle. It's too late to separate the two pieces so I'll just let it sit for a few more days before handling. I have to sand and stain my portable framework anyway. The problem with LN is that my layout is coming along VERY VERY VERY slow so a tube of the stuff usually dries out after using it for a few joints. I have yet to finish a tube of anything (caulk, silicone, etc.) before it dries out. Could become costly over time.
LN...I always shove a big nail in the end to help seal the end then either pry out the nail clearing the passage, or cut off some of the end, and i'm ready to go again.
MK, try picking up a large wire nut. The plastic kind that is used to cap two twisted wires together. After you use the LN just twist it on the end of the tube, when you want to use it again twist it off. I can usually keep a tube fresh for a couple months this way,and when the tube is empty I use the nut for the next tube!
Here is a thought. The glue in the center may never dry. Once the edges dry and seal around the edges no moisture can get out and the glue wont dry. Just like in the bottle. When aplying the glue do a zigzag pattern. never go completely around the edges. This will alow air to escape. HTH Steve
I did that once a few years ago. 3 weeks later I went to carve a tunnel an the middle was still a bit gooey even thought the mountain was solidly together. It may take months or YEARS for it to be completely dry. Mark in Utah
I now punch holes here and there through the assembly with a nailset. Seems to let the center dry. But yes, I've had gooey spots in the middle after months of "drying."
yellow glue is always gonna take longer than white glue, but its also a helluva lot stronger. Try increasing the temperature in the room a little too.... should help. Sounds like its pretty cold there!
I use a thin epoxy resin. With a foam paint roller you can coat and laminate six 4' x 8' sheets together in about a half an hour. It does not need air to cure and sets up completely overnight. Only disadvantage, besides being more expensive, is if you are sculpting with a hot wire cutter and making a cut that is at a very shallow angle across a glue seam, the hard epoxy tends to deflect the hot wire a little more than the foam. Nelson
if you've got some already started, you might be able to cut out a square or rectangle in the middle to allow air in, then replace that section with another. a different idea is to hold everyhting in place, then "drill" a hole down throught the layers, just a little bigger than the end of the lLN tube and fill it up, creating a "pin" of LN going through the layers. that should help hold it HTH beast
What would happen if you cut very small scores in the foam before gluing? Would it let air in and facilitate drying?
