Question on Caulk to glue foam

[ebblake]

Can anyone tell me what is the best caulk to glue foam. I am trying to cement 1/2" foam board for tunnel walls.  Thanks

[Ken G Price]

For many years I have used DAP or Loctite, Tub and Tile caulk.
For foam, track, roadbed, plastic sign sheets cut for roads and car parks, etcetera.
It only takes a thin, but even coating for most applications.

I use the one that dries clear so when laying track it does not show through.

[K487]

Well, I've used caulk for many, many purposes, indoors and outdoors.  

My overall favorite is DAP's Dynaflex230 Clear.  It comes out of the tube (I use a caulking gun) white but dries clear.  It sticks to dry surfaces easily, and I often use my pointer finger to push it and spread it where it needs to go.  

On my model RR I've got my 3 layers of layout foam "glued" together with caulk, and it's not come loose in over 20 years (and I've moved my layout twice.)

I also use this caulk to "glue" weights inside my HO diesel engines - haven't had a single weight come loose.  To apply the caulk I use a dental pick or toothpick.

Another thing, as this caulk "dries" it does not harden - it's still got some flexibility.

And lastly, I have a metal carport, and for extra (anchor-type) support  I welded two metal pipe posts (with flattened ends) to two of the carport's metal supports and welded the other ends  diagonally down to two T posts sticking out of the ground.  After brushing the welds and wiping them clean, I then smeared the welds with this caulk; in 12 years there's not one sign of rust growing.

K487

[Ken G Price]

I used to use a caulking gun set up also, but after opening a tube for some small job, then finding it dried up the next time I used it, it was wasteful.
With the plastic squeeze type tube, I can just squeeze a little, tap the bottom of the tube to clear the caulk in the nozzle back into the tube, put on the lid and ready for next time. I find it much easier to control as it takes only one hand on the tube.

Try both ways and find what works for you.

[kewatin]

why would you use caulk when cheap electric epoxy glue gun sticks work so much better and less mess,not to mention that they are cheap at wally world. i use it to sandwich foam together and in all my tunnel s&even to glue tunnel portals trees etc. built the last 4 layouts this way.again this is what works for me after all the yrs of experimenting with other products.even held plaster rock castings in position .
regards&later KEWATIN

[Ken G Price]

I like to be able to use my fingers to spread the caulk quickly and easily where I want it.
No way am I going to do that with hot glue.

I also do not have to rush with caulk as it does not harden fast. Gives plenty of time to make adjustments.

I do have a glue gun and never fount id to be practical. I never have to heat up caulking.

As I said before, use what works for you.

Oh, an other product that I tried was Gorilla Glue. An other waste of time and money.

[the Bach-man]

Dear All,
I still rely on indoor/ outdoor carpet tape to fasten foam.
I've used caulk and months later it's still wet.  The tape is amazingly strong.
Try it!
the Bach-man

[Ken G Price]

Dear All,
I still rely on indoor/ outdoor carpet tape to fasten foam.
I've used caulk and months later it's still wet.  The tape is amazingly strong.
Try it!
the Bach-man

Tried the tape along time ago.
Maybe you are putting on to much caulk. Tub and Tile caulking should not stay wet. There are other types of caulking that do not work as well.   

[rogertra]

http://www.homedepot.ca/product/pl-300-foamboard-adhesive-300ml/972908

Cheers

Roger T.

[jbrock27]

Hey Balakey, are you looking to glue the foam board to other pieces of foam board or to something else?

[ebblake]

I am gluing a 1/2 inch piece of foam to a piece of plywood for the tunnel walls.  Thank you to all the answers and help!    Bud

[jbrock27]

Look for Liquid Nails Heavy Duty Construction Adhesive from a big box store like Home Depot or Lowe's.  I used it to secure all my foam board to my plywood table top.  If getting a tube for a caulking gun is going to be too much for what you need, follow Ken's recommendation and look for a resealable tube version of this stuff.

Hope that helps.  Good luck!

[ScottyB]

Elmer's white glue seems to work just fine for me. All other suggestions are very good as well.

Scott

[mabloodhound]

The best "adhesive" latex caulk (washable off your fingers) is Pheonsil, a DAP product at HD and Lowes.  Will NOT eat the foam and sticks to anything.....forever; but can be separated later with just a putty knife.
Used it for years in my construction business.

[jbrock27]

Phenoseal.  Yep, stuff's highly recommended by most home improvement contractors I have run across.