Post by aggiedan97 on Dec 15, 2019 13:12:10 GMT -5
I'm new to bowl turning, and resin casting. I have turned some acrylic pen blanks before, but nothing I poured. In an effort to salvage a small bowl I gouged a couple of holes in, I cast Alumilite Slow Cure Clear in a pressure pot.
Casting went well but turning is terrible. Tools are extremely sharp, even switched to carbide w/same results. Brittle and turns worse than end grain. Speeds are slow and pressure is fairly light. No pretty streams of shavings.
Is this your experience with Alumilite Slow Cure Clear?
I've seen others use their products w/o issues like this. BTW, I did use a scale and mixed by weight, not volume, as they recommend. Exact same portions and the dye and pearlescent are also Alumilite brand.
Last Edit: Dec 15, 2019 13:17:26 GMT -5 by aggiedan97: added images
I turn Clear Slow a lot, and I have miles and miles of pretty streams of shavings. I don't use any special tools or carbide. Don't get me wrong, urethane resins will chip while turning. When it happens to me I find it is one of three things causing it. 1. Dull tools. Ruled out in your case. 2. Trying to take off too much material at once. Just kiss the material, like you would use a scraper. 3. Bad angle of attack at the cutting edge (most likely). When turning wood, you want your edge to contact the vertical center of the piece. The resin prefers that you be just slightly lower than this. If you're using scraper/hollower type edges this can be accomplished by simply raising the handle of the tool a bit. This simulates a "negative rake" cutter to some degree. If you're using gouges then you'll just have to practice with your toolrest slightly lower.
You'll get the hang of it, just keep at it. Other brands of urethane will act the same way. Urethane is not a good media for a beginner so have patience with it. The results can be spectacular.
Let us know how it goes. It's gonna be hard to clean up all that chipping, you might consider pouring another layer of resin and starting over. There's no problem with the resin adhereing to itself as long as the surface is clean. I use 91% iso alcohol for cleaning.