Q+A On Rotocasting

Hey.

With my current plans I recon it would be a good move to make a rotocasting machine up.
I have seen a few threads on doing this, Ill do my best to enclose my own plans for everyone should I go ahead...
My thoughts are a machine large enough to handle nothing bigger than a helmet, although I can see it being put to use more with guns- I think approx a 2ft square area for the mold jacket should suffice.

Now, what I don't 'get' is really the use of the resins.
I am hoping people can share their experiences here....
If anyone here uses roto machines, do/ can you use basic 'fast cast' ?
How about softer resins/rubbers, will they still work with this process?
I am concerned over the resin falling away from the mold surface if the cure is too slow, for instance?
Is there a known relation between the speed of rotation and cure?

Any advice is appreciated ;-)

D

great thread , I too understand the basic machine just wondering about all you asked about

I used Smooth-cast 320 resin. For molds, some great stuff to use is Silicone Inc's GI-1000.


FB

The resin that I typically use is Smoothcast ROTO, which, as the name implies, is designed for rotocasting.

For lack of a machine (yet!!) I slush cast. What I find is that you need to not put too much resin in, and need to keep it moving at a nice consistent pace. If you move too slow, the resin will start to drip down off the sides. If you keep it going at a good clip it will hold well.

The ROTO kicks slowly... it's not liquid->solid, its more like milk -> honey -> chilled honey -> cool caramel -> solid (and now I'm making myself hungry!)

As it thickens, it stays on the surfaces better.

I've recently been adding some of Smoothon's Urefill 3 filler to the ROTO. It thickens it up a bit right off the bat, which makes it build up thicker layers faster. Too much filler and you start losing surface detail / getting bubbles, but a little definitely helps.


I'm hoping to build a roto caster this summer, so I'll be following this tread closely.

stormtrooperguy said:

The resin that I typically use is Smoothcast ROTO, which, as the name implies, is designed for rotocasting.

For lack of a machine (yet!!) I slush cast. What I find is that you need to not put too much resin in, and need to keep it moving at a nice consistent pace. If you move too slow, the resin will start to drip down off the sides. If you keep it going at a good clip it will hold well.

Click to expand...

I second this. I've been using smoothcast roto for my slush castings, works great. It's pretty strong material and still has a little flex to it after it's cured.

Cheers!
Ill see what I can come up with re the machine.
Looks like the plans I have seen on the forum and online have used a microwave turntable motor, which seems cool but would it have the torque?

If you go to:
Home
You'll see a roto caster that allows for much more control over the process and at a greater price!

CRWilson

CustomCreations said:

Hey.

With my current plans I recon it would be a good move to make a rotocasting machine up.
I have seen a few threads on doing this, Ill do my best to enclose my own plans for everyone should I go ahead...
My thoughts are a machine large enough to handle nothing bigger than a helmet, although I can see it being put to use more with guns- I think approx a 2ft square area for the mold jacket should suffice.

Now, what I don't 'get' is really the use of the resins.
I am hoping people can share their experiences here....
If anyone here uses roto machines, do/ can you use basic 'fast cast' ?
How about softer resins/rubbers, will they still work with this process?
I am concerned over the resin falling away from the mold surface if the cure is too slow, for instance?
Is there a known relation between the speed of rotation and cure?

Any advice is appreciated ;-)

D

Click to expand...

I'm just about finished with my rotocast machine. 1/2 hp motor and all. I will be trying Smooth-on's roto products and I also want to try their Task plastic for rotocasting.

Tommy