Cholla Cactus question

[ttpenman]

I know this is popular for casting. But, do you need to stabilize it also, before casting? I have some to try so I thought I should ask the experts.

Found a good used vac pump from a friend who upgraded his auto AC recharge system. Will pull 27" (at 800 ft. above sea level) so I think (?) that should work.

Jeff in northern Wisconsin

 

[OKLAHOMAN]

If your going to use PR you want to first make sure all the dirt is out of the inside, then make your self a jig that will hold the cactus standing up. Wrap the cactus with painters tape and be sure to wrap it about 1/2 inch above the end of the blank (PR will shrink and this will let the pr harden to the top of the blank). Pour the resin into the wrapped cactus. This way you'll have no wasted resin'
I see no reason to pull a vacuum, just put into your pressure pot at 40psi for an hour then take them out, you can now place in your toaster oven for an hour @150 degrees and you now will have a cast Cholla Cactus... Cut, Drill and turn...PS you'll turn the painters tape off.
If you use Alumilite the same thing except you'll want to place the cactus in the toaster oven first for about 2 hours @150 degrees to make sure they are dry before adding the resin (Alumilite and Moisture don't mix).
That's how I do it others might have different ways.

 

[sgimbel]

I just put some cholla in some 3/4 x 6' molds and poured PR in and then turned it. No pressure no vac I poured the PR in before it had any chance to set up and had to problem, no bubbles or voids. It was cleaned very well and bleached. Maybe I was just lucky.

 

[Dai Sensei]

Poured mine in a silicon vertical mold with round tube holes and vacuum to minimise shinkage in the PR. I did clean them then sand the outsides to fit the mold prior to casting.

 

[clapiana]

you do not need to stabalize so no vacumm needed. i do clean out the inside of the cactus as best as possible with a round file. i also use a razor to quickly clean out each hole.

i tried using painters tape which was a mess ;( i also tried putting the cactus blank in a small plastic bag and then wrapped painters tape around it tight which was a little bit better but not much. in the end i decided that the resin saved wasnt worth the mess and casted the cactus in a silicon mold similar to how i cast a pine cone.

i do use pressure to ensure good penetration. if the cactus has larger holes you could get away without pressure.

resin is much easier to use vs filling each hole with sand & CA.

lots of trials and errors using this cactus but the results are cool when you get something to the finished stage.

 

[ttpenman]

Thanks for all the advice. Hopefully I will have something to post soon.

Jeff in northern Wisconsin

 

[Richard Van Hulle]

Which six mica powders might be best to start out with?????