Brand new to casting.....need advice

[Parker]

I've been reading in this area of the website a LOT lately. Had a guy from another website send me a PR blank that I think just turned out awesome, so I'm interested in giving it my own try.

All of these contraptions......are they really needed? I'm seeing where some folks say you don't need to de-gas, or vibrate, or any of that stuff? What's right and what's wrong, because I sure don't know. []

If I need to get a pot, is there anyone on here that assembles them and sells them?

The blanks I will eventually be making, in general, will be in PVC pipe 1 1/2" wide, and 7" long.

What'd you all say?

Here's that first PR call I turned. It sounded AWESOME! I auctioned it off for handicapped hunter benefits, and it went for $125.

I know if I'm going to work this stuff much that I'll need to get a good buffing wheel, and micromesh and the likes, but I was happy with this first try.

Parker

 

[gketell]

You don't HAVE to have anything other than your mold and the resin. But it will turn out better if you have a way to pressure/vacuum it. When you mix it you WILL get air bubbles into the mix. When you pour it some will come out but if you make it too hot they will solify in. If you make the mix too cold then the mix will "wash out".

At the very least you probably want to have a pressure pot so you can squeeze the bubbles down to insignificance. Heck, for one 7" tube at a time I bet you could make a pressure pot out of more PVC. Schedule 80 has a 200+ pound burst strength so you could glue one end cap on and put a threaded cap on the other side. Drill the threaded cap and add a tire valve (schrader valve). Cast your 7" tube, stand it up inside the 2" sched 80 tube, thread on the cap and "inflate". How well it works would depend on how well the threads seal.

GK

GK

 

[R2]

That is a great looking "wotsit"[][]

 

[drferry]

Parker,

Alumilite Corporation's web site has all the equipment you would need, including vacuum and pressure pots. I just received my stuff from them and I'm eager to get started!

 

[Parker]

Interesting idea GK. What PSI am I looking to reach?

So.....I'm not actually taking the bubbles OUT of the mixture, but compressing them, correct?

This is becoming interesting!

Parker

 

[Parker]

Originally posted by drferry

Parker,

Alumilite Corporation's web site has all the equipment you would need, including vacuum and pressure pots. I just received my stuff from them and I'm eager to get started!

Thanks! I'll check them out.

Parker

 

[BRobbins629]

So.....I'm not actually taking the bubbles OUT of the mixture, but compressing them, correct?

Parker

When you use pressure to cast, you are just allowing the air go into solution, much the same as with gas in a soda bottle. When its under pressure on the shelf, we don't see any bubbles but relieve the pressure and they appear. There is not nearly enought pressure created in a pressure pot to compress them. But for whatever reason, casting under pressusre, particularly for clear casts, does minimize or eliminate bubbles.

 

[Parker]

Originally posted by drferry

Parker,

Alumilite Corporation's web site has all the equipment you would need, including vacuum and pressure pots. I just received my stuff from them and I'm eager to get started!

Wow their pots are expensive. Looks like I'll be making my own custom pot.

Parker

 

[Parker]

Thanks Bruce. Great explanation!

I'm learning at the speed of light today! [8D]

Parker

 

[gwilki]

Parker

I did exactly as Greg told you. I had already made a spud gun, so I just used the reservoir of it as a pressure pot. I pump it up with a bike pump to 80 psi, and it works like a charm.

I have a HF pot now, for casting several blanks at once, but I still use the pvc one for one offs.

I don't bother to vacuum the Alumilite, and I don't have any bubble problems.

 

[Parker]

Thanks GW.

So that cap idea on the PVC will hold 80 pounds of air pressure huh? Cool! Sounds like I'll just be making a couple of them. [8D]

Parker

 

[Firefyter-emt]

Bad idea on the PVC for preasure!!! Look it up and you will find MANY people who have used PVC for airlines and had it blow up. The 200psi is water rated, not air. PVC is not tested nor rated for compressed air useage. There is a reason the metal tanks we use for paint pots even have a rounded bottom in the tank. Please do not mess around with this, you are in for a big mess if this blew up and could cause serious injury. With the chemicals used for this and the length of time needed, just do it right the first time, it's not that expensive.

EDIT: Read this: http://www.osha.gov/dts/hib/hib_data/hib19880520.html

Here is my very simple tank, the vacuum part can be added down the road if you like without any changes. All you need for PSI only is the tank, a new combo gauge, one reducer fitting, a 90 degree elbow, the valve, and the air fitting. These can be bought for about $10.00 in addition to the tank. Nice and simple, clean and easy to use.

And here is my vacuum pump hook up, maybe $20 with the chuck end and fittings.

 

[Parker]

Okay, so now I guess I'm NOT making one out of PVC.

This is starting to sound like dangers outside of my know-how. I sure don't want something blowing up on me. Is there a chance of a part on one of those pots blowing up on me?

Anyone have a pot that's made right that they're looking to get rid of? I don't know that I'd be confident enough in my abilities in putting all of those fitting together correctly. I'll have to do some more research.

I wonder if there's anyone in the KC area that could help me build one? [?]

Parker

 

[gketell]

The pots are rated for 80 PSI. You only need to pressurize to 60 maximum (and the kings of casting (Ed and his snakeskins and Mesquiteman and his cactus blanks) don't go above 40 PSI.

FFEMT, thanks for that link!! It was informative, to say the least.

GK