My new HF pressure pot just blew and almost killed me!

[Phunky_2003]

And let me verify my post.

I would say if properly used the HF pot would be safe at lower pressures for normal casting. I personally would look into something else if casting worthless wood type casting where the pressures would be higher.

 

[MesquiteMan]

Which pot are you referring to, Jeff? The Binks that I have are code stamped. The HF pot is not, of course. Neither is the CA Tech pot.

I presume these are not ASME code-stamped pots? If that's correct, and there is any concern about material integrity or workmanship, a hydro test to 1-1/2 times the design pressure might be a reasonable idea before putting it into service. That doesn't eliminate problems with the clamping process every time you use it, but it could expose bad welds, poor machining, or material problems.

 

[mrclean08]

Aren't the clamp styles of the Binks and HF pots similar though?

 

[jeff]

Which pot are you referring to, Jeff? The Binks that I have are code stamped. The HF pot is not, of course. Neither is the CA Tech pot.

I presume these are not ASME code-stamped pots? If that's correct, and there is any concern about material integrity or workmanship, a hydro test to 1-1/2 times the design pressure might be a reasonable idea before putting it into service. That doesn't eliminate problems with the clamping process every time you use it, but it could expose bad welds, poor machining, or material problems.

Curtis, I started composing that reply before I saw your post. I was referring to the HF pots.

 

[toyotaman]

I've not owned or used a pressure pot but when your putting the air in "Is it really necessary to put that much pressure in there"? Would 30-40psi be enough?

 

[MesquiteMan]

Aren't the clamp styles of the Binks and HF pots similar though?

Yes, as I said above, the HF is a cheap clone of the Binks pot. The clamps are not an issue, however. It is the cheap, flimsy steel the lid is made from on the HF that is the issue. When using an HF pot repeatedly, if you tighten the clamps in the same spot, you will create a dimple in the lid. With the Binks pot, this is not an issue no matter how much you tighten the clamps. The thin steel on the HF pot lid can also flex and distort but the Binks is so thick it will not.

Your mileage may vary but for me, if I am going to be creating a potential bomb in my shop every time I put air in one of these things, I sure as hell don't want to trust cheap Chinese steel and manufacturing! My life and limbs are worth more than the extra money I paid for a good setup. Once you have had one blow, even if it is possibly due to your modifications like my explosion was, you will never want to trust you life to cheap again!

 

[PenMan1]

Well said, Curtis!

Besides all of the obvious ramifications that come with an exploding HF paint pot, they sure are hard on underwear, too! Even if you escape harm from the explosion, your drawers may not be so lucky DAMHIKT!

 

[mrclean08]

Aren't the clamp styles of the Binks and HF pots similar though?

Yes, as I said above, the HF is a cheap clone of the Binks pot. The clamps are not an issue, however. It is the cheap, flimsy steel the lid is made from on the HF that is the issue. When using an HF pot repeatedly, if you tighten the clamps in the same spot, you will create a dimple in the lid. With the Binks pot, this is not an issue no matter how much you tighten the clamps. The thin steel on the HF pot lid can also flex and distort but the Binks is so thick it will not.

Your mileage may vary but for me, if I am going to be creating a potential bomb in my shop every time I put air in one of these things, I sure as hell don't want to trust cheap Chinese steel and manufacturing! My life and limbs are worth more than the extra money I paid for a good setup. Once you have had one blow, even if it is possibly due to your modifications like my explosion was, you will never want to trust you life to cheap again!

Right you are, Curtis. I searched for the nearest Harbor Freight Tools store near me and actually got to see this pressure pot in person. Immediately upon inspection, the lid felt flimsy and cheap. I examined the lid more closely and totally the noticed the indentations/dimples on the lid from the clamps. The lid I saw seemed like it wasn't even cut evenly and was somewhat already warped. (Was able to take a few pics w/ my cell phone.)

Easy pass for me on this product. :ghost: Will be getting the Binks or C.A. Technologies pot instead.

 

[widows son]

TANSAAFL -There Aint No Such Thing As A Free Lunch -- I just checked my Binks pot that's at least 20 yrs old. Stamped 80 psi in big letters. I actually used it for painting at 60 psi + and have never had an issue. It also says "Made in USA" on it.

 

[workinforwood]

The mods to the pots we use have no effect on the performance. If the pot is used for painting it will actually cycle more times than a caster would do. The mods are barely mods at all. You put in paint, attach compressor and gun on other end, when gun is not being pulled the pot is a closed system same as casting. You paint for hrs the pressure will constantly be dropping and rising which flexes the pot many many times. As a production type caster, the abuse I put a pot through is far less than a pro painter. Of course you aska pro painter if they use HF pot they likely laugh at or punch you! I would bet if there's a house painting forum you will find threads about HF pot exploded paint all over house.

I love my CA pot, it has cool features others don't have, priced reasonable, inside diameter 1/2" wider and built like a brick sh#@ house!

 

[workinforwood]

My guess is right. Search Harbour freight pot exploded. Not just penturner threads, painters can't even use it. Also first hit is pdf from HF says pot may explode at max rating. We want pots to reach max without exploding! An 80 lb pot should not be used beyond that but still handle 80.

Also saw some farmer bought hf 50 lb anvil and it exploded from using 3 lb mallet, lol...HF=Holy F#*@!

 

[sbell111]

My guess is right. Search Harbour freight pot exploded. Not just penturner threads, painters can't even use it. Also first hit is pdf from HF says pot may explode at max rating. We want pots to reach max without exploding!

A better plan would be to not put 80 psi in the pot. Nothing we make requires 80 psi, so why use that much in any pot?

 

[workinforwood]

Nothing you make perhaps, but not me. After thousand of blanks, I know which ones I do that will fail with less pressure. Its ebarrassing issuing refunds do to uncrushed air pockets.

 

[sbell111]

You are, of course, correct. I don't know anything about your processes. I do know, however, that when I cast items in my blanks, such as watch parts, snake skin, cholla, shredded money, and other miscellaneous chotchkies, I don't need that much pressure. I also don't need that much pressure when 'clear casting' or making worthless wood blanks.

Your procedures may require you to take your pots to 80 psi, but mine don't require my pot to be anywhere close to that.

 

[kenspens]

wow glad your ok! i bought an older craftsman paint pot that has a working pressure of 80 psi but i stay well below that and have never had any issues!! and to think i almost bought a hf pot!! whew!! sounds like the show on tv called flying anvils!!lol on the green channel they blow 100 pound anvils into the air with gunpowder and run like hell!!!lol
wise decision to trash it! if it is not too old try getting harbor frieght to refund you the money that you paid for it!
ken
kenspens

 

[toyotaman]

What would be a min. pressure needed to do the castings??? 20lbs,30lbs.50lbs??????????? Just wondering... Looks like 30lbs would be plenty as long as you leave your items in the pot a little longer. Right,wrong????? Like I said, I do not own a PP but when I learn enough I will.

 

[DurocShark]

In my pipe molds I keep it between 35 and 40 psi. In silicone molds, I don't usually go over 25. The molds will distort if you go higher.

 

[tt1106]

I'm using a Cambell Hausfeld pot (2813) and it worked great. 4 hours or so at about 35 lbs. The blanks turned out perfect.

 

[workinforwood]

Normal recommended pressure for Alumilite is 50 lbs. That's what I cast most my stuff at. PR can be less or depending what you make no pressure at all required.

Ya'll realize this is an old thread someone dug up from about a year ago right?

 

[PenMan1]

Normal recommended pressure for Alumilite is 50 lbs. That's what I cast most my stuff at. PR can be less or depending what you make no pressure at all required.

Ya'll realize this is an old thread someone dug up from about a year ago right?

Yeah, the economy is so bad they are showing "reruns" on the IAP.

Thank goodness FOOTBALL starts Thursday night!!!

 

[workinforwood]

No doubt the Bengals are under pressure and on pot too!

 

[Leather Man]

Now that's funny..........Are there any instructions out there that would show or tell how to encase your PP to minimize the danger of failure? I have an old Binks pot that I fixed up but have yet to use.
Thanks
Ben

 

[bruce119]

Now that's funny..........Are there any instructions out there that would show or tell how to encase your PP to minimize the danger of failure? I have an old Binks pot that I fixed up but have yet to use.
Thanks
Ben

Here is a 2 year old link to Curtis when his pot blew. Notice he has a nice nifty cabinet that secures the pot. It didn't contain the lid but I am sure a loose pot would have been much more exciting. I think the biggest danger is when adding pressure you could always attach you air hose and control adding air from a safe distance with an in line shut off valve. One thing you don't want to do is to be looking straight down on your pot when filling. I stand to the side and that's when only filling to 25lb I start to sweat when I fill to 60lb (far & few between now-a-days)

.

 

[Justturnin]

Hmm so really what failed Curtis is the Hot Glue. I am sure it just stretched out allowing his savers to slip out.

Question - Do the Pots get hot or warm up during pressurization? If so I am sure that is what caused the Glue to fail and not the quality of the pot itself.

 

[randyrls]

Notice he has a nice nifty cabinet that secures the pot. It didn't contain the lid but I am sure a loose pot would have been much more exciting.

Ben; SCUBA dive shops have "shrouds" that surround a tank being pressurized. I was in the Caribbean and heard a tank fail in the back. LOUD BANG! The guy came out a few seconds later; he looked like he needed a drink!:laugh:

 

[sbell111]

Hmm so really what failed Curtis is the Hot Glue. I am sure it just stretched out allowing his savers to slip out.

Question - Do the Pots get hot or warm up during pressurization? If so I am sure that is what caused the Glue to fail and not the quality of the pot itself.

The only heat generated in the process is from the resin curing. I don't see how this could be enough to cause glue to fail.

My thinking is that the pressure caused by cranking down the screws broke one of the glue joints. From there, the 'pot saver' was able to move just a bit. This movement resulted in one screw that was not sufficiently secured, leading to a place that a leak could occur at high pressure. Once that happened, the pot was DONE.

 

[BlackPearl]

I recognize that I am probably wrong on this but, I ride bikes a LOT I keep my air pressure at 110 Lbs in the tires and have accidentally been up to 150#. I always use a pump because the only time I ever used a compressor the tire blew. It was my home compressor and it was only set at 65# but the force of the air actually tore the tire and dismounted it.

Could the air have been "pushed in" too fast? The OP said that this is only the third time he had used the pot were the fasteners attached correctly?

I am thinking of trying some casting but this has me a little nervous. How much time does one have to get the pressure up? Would a floor pump be fast enough? I know it could do the pressure. Mine pumps about 15 Cubic inches a stroke so it would only take about three or four minutes of pumping to reach 60# if that.

 

[mrclean08]

I recognize that I am probably wrong on this but, I ride bikes a LOT I keep my air pressure at 110 Lbs in the tires and have accidentally been up to 150#. I always use a pump because the only time I ever used a compressor the tire blew. It was my home compressor and it was only set at 65# but the force of the air actually tore the tire and dismounted it.

Could the air have been "pushed in" too fast? The OP said that this is only the third time he had used the pot were the fasteners attached correctly?

I am thinking of trying some casting but this has me a little nervous. How much time does one have to get the pressure up? Would a floor pump be fast enough? I know it could do the pressure. Mine pumps about 15 Cubic inches a stroke so it would only take about three or four minutes of pumping to reach 60# if that.

I am interested too in the same question. What is considered too fast and too slow to put air into the pot from the air compressor?

 

[bruce119]

I recognize that I am probably wrong on this but, I ride bikes a LOT I keep my air pressure at 110 Lbs in the tires and have accidentally been up to 150#. I always use a pump because the only time I ever used a compressor the tire blew. It was my home compressor and it was only set at 65# but the force of the air actually tore the tire and dismounted it.

Could the air have been "pushed in" too fast? The OP said that this is only the third time he had used the pot were the fasteners attached correctly?

I am thinking of trying some casting but this has me a little nervous. How much time does one have to get the pressure up? Would a floor pump be fast enough? I know it could do the pressure. Mine pumps about 15 Cubic inches a stroke so it would only take about three or four minutes of pumping to reach 60# if that.

I am interested too in the same question. What is considered too fast and too slow to put air into the pot from the air compressor?

Personally I don't know the physics but I don't think it would matter how fast the air goes in as far as the integrity of the pot is concerned.

However ... for our purpose we want to add it on the slower side. First off if you add air too fast it will disturb your molds and possibly blow the resin out of the mold. I had this happen in the beginning I put a "T" on the inside nipple of the lid so the air does not blow straight down on the molds. Next thing that comes to mine when blowing air fast is condensation. If you add it too fast you risk condensation forming where the air enters and you could get some water drops on your mold.

How fast or slow do I add the air for me it's a feel thing not fast and not too slow. I figure I'll take about 15 seconds or so to put 25 psi in. Now you could certainly blast 25 psi in, in probably a second or two but you would have a mess inside your pot.

JMHO

 

[Smitty37]

Probably not

You might just have court case against them . I just checked their website and looked up the owners man for your pot and they do indeed say 60 psi max working pressure . I'm not sure when they changed it but it now says 80 psi max .
As I said my pot is about 2 years old and I would still never use it at more then 40 psi infact my pressure relief valve pops at 45 psi . Bottom line is I don't even use it anymore as I found I can cast without pressure and get bubble free castings .

This is America and you can sue anybody for anything - but I think damages are seldom awarded for almost getting hurt. I'm sure if the pot is returned they will give the money back..unless it was materially changed by the alteration. And, with no more information than I have right now I'd be mighty suspicious.

 

[workinforwood]

When my pot blew up it was at around 50 lbs of pressure and everyone around here said I was crazy. Since then several have blown, like Curtis' an Parsons and a few others. My pot did not fly across the shop. It blew up about 1-2 minutes after it was filled. The pot turned oval instead of round and the lid had a nice curving bow in it. The lid probably jumped only a few inches high. The pot however also jumped just enough to cause it to land on its side which in turn allowed all the resin to come pouring out and make a huge mess on the counter and floor. If I had been standing there, I would not have been injured more than possibly a scratch. I heard others say the lid flew past their heads, hit the roof etc. I was not there, can't say it's true or not, but these pots definitely do explode at far less than 80 lbs, and less than 60 too. Far as how fast air goes in, I don't know anything about it, I just pull the trigger and fill that baby fast as she goes.

 

[Greg O'Sherwood]

Not trying to highjack, but I started using vacuum with a vac chamber instead of pressure, any risk there? Full vacuum.

Is anyone else using vacuum?

.

 

[workinforwood]

Yes, too much vac will cause your pot to implode and a black hole to open up sucking your entire shop into a new dimension where there are no pens because all communication and learning is done through telepathy!

 

[tt1106]

Yes, too much vac will cause your pot to implode and a black hole to open up sucking your entire shop into a new dimension where there are no pens because all communication and learning is done through telepathy!

+1(extra characters)

 

[bruce119]

Yes, too much vac will cause your pot to implode and a black hole to open up sucking your entire shop into a new dimension where there are no pens because all communication and learning is done through telepathy!

:laugh: yea that's true BUT an implosion is better than an explosion and your more likely to survive. Unless perhaps you got a rocket fueled turbo charged vacuum pump
:biggrin::biggrin::biggrin:

But really why vacuum. The only time I now use vacuum is when I make molds and I want to degas the silicone before poring. The vacuum dose something like make the dissolved gasses in the resin/silicone into bubbles large enough so they can rise to the surface and burst. I found vacuum for casting only good for degassing the resin BEFORE you add the hardener and then it caused much more problems then it's worth.

 

[elody21]

Well since I am in the process of starting to cast again after 2 years off I took this post very seriously.
I have made up a design for a "cage" for my pressure pot. I understand that the risks probably are minimal that it would blow, but it only takes one time and a pretty blank isn't worth the risk.
I had originally planned to use gas pipe but there are many difficulties with that.
So I am using 3/4" copper pipe because of it's ease to use and I am going to run a solid length of steel rod down the center of the pipe. I know that if the pot did blow the cage would be damaged but I am hoping it would stop the lid from flying.

I will post a picture when I get it done but it might be a few days.

Alice

 

[diamundgem]

I built one of the HF Pots and tried it one time to see if it leaks. It was Ok but have never used it again after seeing this same story before here on the site. I am afraid to try it now.

 

[mrclean08]

Well since I am in the process of starting to cast again after 2 years off I took this post very seriously.
I have made up a design for a "cage" for my pressure pot. I understand that the risks probably are minimal that it would blow, but it only takes one time and a pretty blank isn't worth the risk.
I had originally planned to use gas pipe but there are many difficulties with that.
So I am using 3/4" copper pipe because of it's ease to use and I am going to run a solid length of steel rod down the center of the pipe. I know that if the pot did blow the cage would be damaged but I am hoping it would stop the lid from flying.

I will post a picture when I get it done but it might be a few days.

Alice

Can't wait to see what your produced cage will look like!

 

[PedroDelgado]

I find this a bit hard to believe. I bought one from HF and I had my Machinist friend look at it and he gave it two thumbs up. We then tested it up to 120psi and it started to leak but never blew up. If a fitting came off (probably not threaded properly), the pressure should have been minimized and nothing should have blown up.
The tank is rated at maximum of 90psi so technically we could have gone as high as 180psi but since it started to leak a little at 120psi, we stopped there.

Anyway,..... I am glad you are OK but the story is a bit ????

 

[PedroDelgado]

If you fill the tank with water (which can not be compressed), it will be safe to test. I do not see the need to go above 50psi. I use vacuum first and then 50psi. There must be at least one valve in order to protect the pressure regulator. If anyone is interested I can send pictures on how mine is setup.
Cheers