I have changed the name of the thread.
I went rummaging through my toolbox trying to find some woodstain and found the tube of silicone sealant I'd put aside.
The reason I'd put it aside was the nozzle had cracked slightly and the entire tube appeared to have gone solid. In the spirirt of honest scientific enquiry I decided to saw it open to check the set silicon properties.
Quote:
Cave Johnson - I'll be honest here people, we're throwing Science at the wall and seeing what sticks
the top 6cm had set solid, but the rest was still, as Kryt said, sticky.
In tropical humidity I had about 6minutes before it started to go solid. I had to work fast people.
this is why there are no pictures. yet.
First thing, I'd need a mold release agent. I sprayed a ceramic tile with a WD40 rip off, dolloped a blob of the silicone onto it and stuck it in the sun. I covered the cut tube halves with clingwrap and stuck them in the fridge - in theory cooler = slower temp reaction.
I grabbed the first set of bits I could find. Stupidly, this did not involve the munitions truck, the small tank or the racer trukk, all items I will need to replicate in time to come.
Instead it was a big skull, small skull and a bunch of weapons from the 40k space marine scout sprue - shotgun, heavy bolter, bolter. I don't even collect marines (though my squats and sisters of battle might find them handy)
Oh, and a grabba klaw from hotwheels and two panels from the 'shrine of the aqulia' by NSGZ. If it works I can build the shrine and a Capitol Imperialas. If it fails, I still have enough panels for the Capitol or a reduced shrine.
Open top molds here, no fancy two parters:
the big skull I embedded intact in a cut in half plastic jar. I'm hoping I'll be able to pop the lid and easily remove it in a day or two. the others were all laid on plasticine in the bottom of little plastic tubs.
BEFORE DOING ANYTHING WITH SILICONE
1) either prepare your work surface - paper, disposable towels, a disposable tub for excess and placing tools in, gloves ect. Silicon will stick to anything. Don't let it stick to everything.
2) Or get a good divorce lawyer. I'm lucky, my wife is reasonably confident in my ability to clear up and, more importantly, I was working with black silicone on a black table she wants to replace in future.
3) If you are not old enough to pay the bills, it's probably best you don't try this. Better to rope in a gullible adult.
4) It also stinks - acetic acid again. don't leave it to cure in the kitchen.
I stuck the plasticine and tubs in the freezer to stiffen up, and went out to check the WD40 as release agent. Now this was a shiny ceramic tile, there's not many things smoother and the bugger was still stuck to it. I've heard WD40 can inhibit the silicone from setting (drives the water off). Mixed evidence, but the edges of it had dissolved slightly. More to the point, I still had to scrape it off.
Cooking Oil has had bad reviews, and besides, anything that attracts ants is a bad idea around here - I've had one burrowing in the plasticine before!
So, onto the other release agent available, bear in mind the time limit is still ticking. So I brushed all the models, plasticine and tub sides with KY jelly. it does work.
I spooned the silicone sealent in smoothing and pressing the silicone in as much as possible. Used an Obital Sander for the vibrating bed. You will have to hold the mold down to stop it jumping over or falling off. Try not to vibrate your fingers for longer then a minute - Vibration White Finger is a classic construction safety hazard. In one case the sander moved all the silicone up to the side of the tub, leaving a hole in the middle that had to be pressed in again. On the big tray holding the wall panels I put a layer of clingfilm down and pressed it firmly in with my fingers. I then filled the tray above the clingfilm with water to keep some pressure on while it cures. I hope I haven't sealed the atmospheric moisture out too much. We'll see.
on a completely unrelated note.
a. Be careful when opening tins of woodstain on a hot day.
b. the best way to remove woodstain from skin and hair is veg oil, followed by washing that off.
c. hot showers to remove veg oil on hot days are not fun.