You're supposed to use premade pattern maker's wax fillets, but I use automotive panel filler (car bog) carefully wiped into the corner by finger and then later carefully scraped with bits of hacksaw blade with the ends smooth ground to various curves.
Me too but around these parts, we call it Bondo. It's very widely available almost anywhere, it's cheap, easily shaped, sanded, painted, adheres well to most substrate, it's great stuff. If you're unfamiliar with using bondo check out Eric Strebel's youtube videos on Bondo.
Tuff-Fill from Freeman's. Been using it for 30 years and never found anything that works better....and we have tried quite a few things.
I hadn't heard of that stuff before so I looked over its MSDS, based on that, it seems to be a specialized version of Bondo, both are primarily polyester resin, styrene and talc using a benzoyl peroxide catalyst
I honestly dont know what the difference is except it seems to feather out and work better than bondo. We tried bondo here but it did not work out too well. The bondo dried out and cracked on first use whereas the tuffill will but usually takes much longer.
Perhaps isophthalic resin with ample milled glass fbers? Bondo isn't the best stuff, resin-wise. I know I went to isophthalic resin when I first tried the stink. This stuff: https://www.tapplastics.com/product..._resins/tap_isophthalic_high_strength_resin/9 The comparisons for odor list it as pungent. They are not kidding.
Everyone says the Tuffill has a strong odor but I cant smell it anymore...probably have a .08 polyester resin level in my blood from all the dust I have swallowed over the years.LOL
I've have and use Tuffill and it's great but sort of depends on what I'm working on. If it is just small filleting say 1/2" of less, I use lightweight body filler (Bondo). They're both just polyester with different fillers. The reason I prefer the lightweight filler is it's close to the hardness of the modeling board or pattern wood so if you need to sand it, it sands evenly and pattern material doesn't erode more quickly than the filler. Tuffill is hard by comparison but if it was a pattern repair that needed to be durable it would be Tuffill hands down. In either case I think technique makes a big difference total time required and quality of result. I mix relatively small batches (with more catalyst because I'm impatient!), spread it initially with my finger and then wipe it in with a ball fillet tool frequently removing the excess filler from the tool with a paper towel so it is clean. It's important to spread the initial pass with your finger quickly so you can work it with fillet tools. I don't remove the excess filler in the wake outside the path of the ball until it starts to kick and get rubbery. Then I remove the excess with a scraper of the same radius as the ball wiper, and then a quick wipe with an acetone wetted rag removes any residual filler that may be stuck on the surface, and creates a smooth finish on the fillet too. It sounds like a lot of bla-bla-bla but I can lay a lot of fillet in a short time that requires no further finish work and looks very uniform. My most usual fillet is 1/8"- 1/4" radius so a little Bondo goes a long way. I've had my quart can of Tuffill for a long time; years. So long it dries out. When it does, I stab the contents 10-15 times with a screw driver and fill the holes with acetone, and put it back on the shelf. Next time I use it mixes up creamy like new. You can thin small batches to suit with a couple drips for better application. Just be careful what you apply it to because acetone will aggressive attack a lot of plastics. Best, Kelly
I use a radius tool but my favorite one is the one I made out of an old hacksaw blade. I put it on with the tool and do not mess with it until it starts to cure. Once it starts curing I will take a knife and trim away the excess on top and bottom of the radius and it leaves a really nice smooth radius that when I do it just right I barely have to sand. Getting the right consistency to make it smooth is key. Temperature plays an enormous role in how long it takes to set up. In the winter without heat you can forget about it setting up, and in the summer when it is really hot you may not get it all put down before it starts to harden. Takes some practice but when you get it right it is nice. Also you can work it and carve it pretty easily before it completely cures.
Perhaps do like MelterSmelter does, only with a runny mix of cab-o-sil and mixed fibers? (Need to add wax for full and proper curing...)
I’ve found the perfect filler and fillet material, Dolphin Glaze. It’s a thinned 2 part very fine filler, similar to bodge or bondo but with the consistency of toothpaste. It also works great for filling the ridges in 3D printed patterns
Seems it's available to us savages here, too - looked it up on Amazon/Amazöon. Does it have a prefered brand/type of hardener?
