Dracos

I discovered this stuff while looking for a filler for my 3-bar grille. I'd never heard of it, so I thought I'd get some to try:



The white dots at the top of the blister packaging seem to be samples. The packaging says the liquid part contains methyl methacrylate, which is used in the production of PMMA and MBS plastics. Nothing I've seen states what material Plast-aid actually is.

I'll be doing some tests later today or tomorrow, and will post the results here. I'll be doing heat and cold tests (oven, freezer) to measure thermal expansion/contraction. Unfortunately I don't have any calipers, so I'm not sure how accurate of measurements I'll get. I'll also do a bonding test to a piece of scrap from modded my grille, and also review how sandable it is, and how it feathers.

Even if it turns out not to be suitable for the grille, I have other non-HRR uses for it.

Dracos

After a bit or research I'm pretty sure this stuff is some type of MBS, because PMMA is Plexiglas. I found some chemical spec sheets that show ABS and MBS are very similar, so I won't bother doing any thermal tests.

I mixed up a small batch and put a glob of it on a piece of grille scrap. I took it out of the mixing cup too early (it wasn't quite putty-like yet), so I cound't work with it the way I expected. But it bonded well.

After it was hard to the touch, I took some tools to it. 100 grit sandpaper worked reasonably well, and it only took a few seconds to put a reasonable groove in it with one of my detail files.

Then out came the Dremel. Response to a 512E abrasive buff was excellent, it went from a dull to a shiny (but not reflective) smoothness almost immediately on a medium speed. It didn't pit like this ABS does. A sanding wheel was effective, however when Plast-aid gets hot, it doesn't liquefy the same way ABS does, but the difference is hard to describe.

Sanding and polishing released more fumes. The sample had been dry about 20 minutes when I got the Dremel out, so perhaps it needs a few hours to gas out completely.

Now, since I worked it at paste consistency, I got a few bubbles in it. To reduce that, I'll have to get some latex to use as molds on my grille. In fact, too much mixing seems to aerate it.

I made a second little batch to use as a glue between two pieces of ABS. It didn't work, because I added too much of the liquid component. Will post again after another attempt.

I didn't bother taking pictures because Plast-aid is milky white, and the photos wouldn't portray it very well.