Alumilite Pressure Pot lid shifting

[Donna]

Hi,
I have the Alumilite pressure pot and am having trouble with it shifting while it is under pressure (I keep the pressure on the low side). I hand tighten the knobs as tight as I possibly can. Does anyone here have any advice for me? Could it be the black gasket under the lid or should I be tightening with a some sort of wrench or something? Any advice is very much appreciated.
Donna

 

[PaulDoug]

Donna, I'm no expert, I haven't even done a cast yet but my first guess would be the lid needs to be tighter. I think the Alumilite site has a FAQ section and if you don't find the answer there you could call or e-mail them. I have a Devilbiss pot and I have to really tighten the lid down or it leaks. I'm going to try to get a new gasket for it before I try using it to cast. I was looking at the pot you have at the Alumilite site and it looks like it have plastic handles. I would try tightening them a little more with pliers but not a whole lot, you could brake them. Also tighten one just snug, do the one across from it same pressure, go to the next one and then the one across from it. Work you way around in that fashion until they are all tight. Hope that makes sense.

 

[Donna]

I appreciate your input Paul. I will try your suggestions and will go easy with the pliers. It's possible that it may end up being a gasket issue. I will call the folks over at Alumilite Monday to see what they think also. Many thanks,
Donna

 

[ctubbs]

I have worked some high pressure vessels and a shifting cover is serious. Try Paul's advice about gradually tightening opposite lugs. It is like putting on a wheel on your car, skip one between each one. I went to Alumilite's site and did not find a pressure pot. If is is similar to other ones, there are probably 4 lugs. snug up one, get the one opposite and snug it, then do one of the other two and then the last one. Now go through it again and again a little at a time until they are all tight. Apply pressure and watch the lid. If it moves any, let the pressure off and add more torque to teh fasteners. Keep doing this until it seals. OH, I almost forgot the number one most important thing here, check the pot rim and the gasket for roughness, gaps or foreign material. The lip and gasket must be smooth and clean to seal.
I hope this helps. Pressure containers are dangerous and can cause injuries. do be careful. You may pm me if need be and I can help.
Charles

 

[workinforwood]

The Alumilite pot is just like the HF pot. I've seen one in person and I can't really tell the difference. It is true about how you tighten the lugs..tighten one just enough to hold the lid down, then go opposite and do the same until all the lugs are holding the lid down and then go back to the beginning and tighten them in the same sort of sequence. If you are putting the lid on tight as you can and the lid moves when you fill it up..I would be scared of that pot...very scared.

 

[Donna]

Thanks Jeff and Charles,
I did what you said about tightening the lugs, and it still shifted. Since I'm not a risk taker, I will be looking into other pressure pots. I will start by searching previous threads here. If there is one that you particularly like, please let me know. I plan on casting for a long time and getting my son into it as he grows, so I need this to be safe.
-Donna

 

[PaulDoug]

Donna, I got mine off of Craigslist. It is a Devilbiss 2 gal. I paid $75 and it included the hoses and Devilbiss spray gun, which I can resale and re-coop over half my investment. Binks is good also. These sell for several hundred new, but if you are patient you can get used ones very reasonable. Mine I bought from a business that purchased it to do one project. It sat for a couple years and the owner decided to get rid of it. It is like new.

 

[Padre]

A shifting top on a pressure pot is not a good situation. If it continues, please call Alumilite as soon as possible.

 

[workinforwood]

I love my CA Technologies pot. The screws that hold the lid down do not dig into the lid, instead it has large fingers out the side and the wing nuts with washers to hold it down. The larger wing nuts are more comfy to use as well, and although the pot holds the same volume, it is wider inside that what you have now. It also has a sweet pressure relief valve and a quick release screw to dump the air out of the pot. It comes with wheels, but is easier to use without the wheels installed.

 

[Donna]

Thanks for all your input. It's help point me in the right direction.
Donna

 

[workinforwood]

You can modify these pots real cheap and easy for alumilite. All I do is remove the big tube under the lid..on a good pot, it will just unscrew pretty easy. Then you go to HF or you can go to an auto parts place and buy a tire filler device. The tire filler has a pressure guage, a trigger, a hose and on the end of the hose is the piece that hooks up to your tire on your car. On the trigger end, you install a quick connect for your air hose. On the tire end, you simply unscrew the end that is for filling tires, so all you have is the hose with male fitting on it. Screw the hose into the lid of the pot, the hole that has the air diverter under the lid. This entire modification should cost you $9. Now the hole that had the big tube on the underside of the lid..you just buy a plug and screw that in the hole, done. Total modification cost, $10 or less. Put a little Vaseline or some oil on the rubber lid seal and you are ready to start casting.

 

[Donna]

That sounds great Jeff,
Thanks,
Donna