Monthly Club Challenge Information & Discussions

June’s challenge is to turn something that blends wood with acrylics. The choice is yours. It could be a hybrid pen, bottle stopper, bowl, vase, or something whimsical. You can either purchase your blank or cast it yourself. This is a perfect opportunity to cast something unique. Let your imagination run wild.

Hi Patrick -

I'll take a shot at this one, as I am a caster and use a fair amount of 'acrylics'. Hopefully, Doug will also add in the conversation.

There are chemical and reactive differences between epoxy and acrylic, but I think for the challenge either could be considered as the 'second medium' which I believe was the goal Doug was trying to get to, so my vote would be 'it doesn't matter'.

Lot's of folks use products from Alumilite - like me. Alumilite resin comes in different chemical formats, so just saying something is 'made from Alumilite' is a misnomer. Alumilite makes casting epoxy and also acrylic products and they work differently, but in the end, I believe both meet the 'second medium' qualifications of the challenge. Other products like Total Boat, Silmar, MAS, PUR and lots of others are also in the market, each offering somewhat different hardness's, color mixing qualities, or UV stability.

Alumilite Clear Cast is a two part casting epoxy. Alumilite Clear Slow is a urethane resin, also two part, that is widely used by pen turners, including me. Lots of people call this an 'acrylic' resin, but chemically it is not. Turning a true 'acrylic resin blank' is a test of your patience - as they tend to be brittle, very chippy, and tough to work, but due to their hardness they polish up really nice! Acrylester is a typical 'generic' name for acrylic blanks.

I don't use the Clear Cast, as I find it too hard to work - it is really made to be a casting or a finish and doesn't like to be turned. It also is more difficult to get dependable color combinations out of as the setting time is a little long for my liking. 

Alumilite Clear Slow on the other hand is a much softer material, works easier, and is pretty easy to get interesting color patterns with by mixing at different times in its curing process. Both products cure out to be a hard material that holds up pretty well over time.

The bigger issue is if you need a pressure pot or not to get a good casting without air bubbles. Epoxy often allows you to gently use a blow torch along the surface to drive out the air bubbles and get a good casting. Most people do not use a pressure pot for epoxy pours, they simply control the mixing of the components and use some heat to clear out the bubbles. Epoxy products have a lot of different working times, but generally epoxy takes a good while to set up - at least 30 minutes or more.

Alumilite Clear Slow must be cast in a pressure pot at about 40-50 lbs of pressure for roughly 4-6 hours to insure no air bubbles remain in the casting. Clear Slow is a heat curing resin and it gets really hot as it cures, taking about 15 minutes of 'working time' before it must be in a pressure pot where it then takes some time to cure.

I don't know if I have answered your question fully, but feel free to ask more!

Kevin

Thanks Kevin that was very helpful info.
I have some left over west system epoxy on hand. A few years ago I made a wood fired hot tub and figured out how to work with. I plan to order Chinese food tonight and will use the plastic soup container as a mold and include some dyed veneer lumber scraps I have in the pour. Not sure where it will take me but I will give it a spin.

Pat
Sent from my iPad

Patrick -