I learned of this trick from Bluebird Studios blog & had to try it myself. That was several months ago & it has definitely been added to my 'toolbox' of techniques. The foam I found right off the bat was Touch 'n Foam No Warp Window & Door Sealant which is awesome because it is reusable; most foams are once you open it, use it or loose it because you can't store it. Albeit this one doesn't last forever; you do have to use it up in about three weeks, but that's a heck of a lot better than all in one day!
The primary victim of the day was a Cantrell 'Rastus' that is here for a hair do. He will be a mold master, so I was given the less than perfect cast since all he has to do in life is be molded. But he had a thinner-than-I-was-comfortable-with head so I wanted to fill it with foam before I was handling him for sculpting hair. Since you do have to use the foam up in a few weeks I grabbed a couple others that have been hanging around; A Baby Flo who's getting a moved head/neck, the other is a Smart Chic Oleana who is getting a whole new neck. So nothing all too major today (actually this was a few days ago). I have used this foam for some really drastic stuff that I'll get to in a mo. }:]
Now, you can go pretty crazy CMing with this stuff on your side. These were the first victims I ever tried using the foam on (below). They are a couple of Merrylegs, heat-&-moved to be pulling ponies (like the drafties but in pony size; look it up!). All these cuts make the model very unstable since some places only have a small bit of plastic yet connecting it to the model.
I cut him down his mold seam, took off his tail & head, then put his body back together widening it with bits of popsicle sticks to prop it up (removing them once the foam cured) & packing-taping it together long enough to foam away! Once that cured I cut his barrel in two to lengthen his back & barrel, braced it together with a dowel rod inside, taped the halves together & foamed that too. I heated his head to straighten the odd dip in his jaws, then foamed it together with the popsicle sticks & tape to widen it as well, then wired it back onto his neck. I heated & straightened his fetlocks to lengthen his legs, wired on his tail at a lower set, Dremeled off here, & epoxy added there. He is not finished, but her looks MUCH better to me now!
The particular foam that I use is fire retardant. I wanted to put that to the test to know what I could get away with if I needed/wanted to heat-&-move anything after having foamed a horse. Back in December of 2016 I took a chunk of cured foam outside to a safe concrete patch, bucket of water at hand, & took the heat gun to it. I used the heat gun much closer, for much longer, at a much higher temp than I ever EVER would on a model horse. It burnt up, as in toasted brown & black & shriveled up to a nasty looking wad, smoked like heck (I certainly would not suggest heating it indoors), but it never actually caught fire. I did not try an actual flame on it since that would never be something that I would need to do.
I won't be held accountable if you burn your house down or asphyxiate yourself on fumes, but my conclusion has led me to be able to do a little heat-&-moving afterwards on some models.
BE SURE to wear a respirator (which I do regardless because of the smoky fumes that can come off of the plastic): it is not a pleasant odor that the foam emits when heated & it's probably seven different kinds of terrible for you too.
Also be aware that the fumes from the foam can are very flammable too. I tested this on a cured piece of foam, not anything fresh from the can.
PLEASE NOTE: Some expanding foam absolutely IS flammable!! My experiment was only on 'Touch n' Foam No Warp Window & Door Sealant' & NO OTHERS. Heat it & any others at your own risk.
...Isn't it lovely how many different ways our hobby can kill you? ;)
Thank you Becky for a lovely write up!
Spring Is In The Air
These happy little flowers are Spring Beauties, blooming off the corner of my house. I couldn't resist photographing them with my new camera. This picture is deceiving; these guys are actually a smidge smaller than my fingerprint!