Let’s take a tour of the pressure pot I use for casting urethane resin. Here is a link to a downloadable PDF file with a list of the rubber, resins and waxes I use in my videos: www.dropbox.co...
I was literally researching this at the time of this posting. We just had a metal failure on our HFT pressure tank 10 minutes prior. The clamps aren't ideal for quick insertion into pressure for our quick-cure applications. Thanks for posting!!!
I recently discovered your channel and the info you provide is priceless. I just poured my first mold the other day and it turned out perfectly with zero imperfections, i was so happy. I cast both wax and chocolate Santa's with it. I so wanna do this more now lol. On a side note I could see maybe modifying your tank to have internal guide rails on the inside of the front face for the lid to loosely slide flush either vertically or horizontally so the chamber wouldn't have to be so deep and so you wouldn't have to store the lid separately. It would probably be a involved modification tho. Idk im not an expert i just love technology of all sorts and wanna make everything.
The design is so simple and ingenious. It closes by itself and you don't need a bunch of bolts to close it. I realy love it. See you next year and have a nice Christmas !
I've been admiring your pressure chamber since I've started watching your videos. I noticed the oval door because that's why manhole covers are round, so they don't drop in. This design is super fast and easy to handle and I love it. I also love the touch of having a muffler for the air release valve. I always have to cover my ears for that, but strangely never thought to use a muffler.
50 PSI pressure are around 3.5 bar. As such, air bubbles in castings become 3.5 times smaller in size when pressurized inside the pot (since earths atmosphere is around 1 bar of pressure at sea level). So, the more pressure inside the pot, the smaller the size of the resulting bubble. Lets of course not forget that a car tire has around 2.2 bar pressure and you can easily understand how this thing exploding can deliver vast amounts of terror! :) Merry Christmas Robert! Can't wait for your next videos!
You explained perfectly why the pressure pot will effectively eliminate small bubbles but not big ones. My tanks are safe up to 125 PSI, but I have found it is not necessary to run them at higher than 50. But I went the air from the mold, not crush it out.
@@RobertTolone It seems normal that you don't run them higher than 50 PSI. If you take a 1cc bubble and pressurize it at 2 bar (1 bar on the gauge), the size of it will become 0.5cc. If you continue compressing it at 3 bar, the size of it will become 0.33cc. So, the change in size is only by 0.17cc compared to the 0.5cc of the initial compression. At the end, you compress it more but the size changes very little. Just for information. Scuba divers have higher risk when surfacing from 10m depth (2 bar) to the sea level than from 20m depth (3 bar) to 10m depth as the bubbles in their blood stream doubles when going from 10m to 0.
I have a pressure cooker that uses the same oval lid design. It's so reassuring to know that the pressure is safely contained. Have a great break. Happy Holidays.
Thank you for this and all your previous efforts. Friday the 8th january I am hiding my face in tears - Merry chrisman and a happy new year to you and all your family ....
As a pressure welder, I was just thinking about getting the material together to make myself a few of these just earlier today and lo and behold, your video on this drops. What serendipity! Many thanks for your videos, you must be a fantastic person to apprentice under. Have an amazing holiday season Robert, and I hope you a healthy and safe new years.
Hi Robert! I am writing to you from Ukraine. I have long wanted to make such a camera, but the simplest version of manufacturing did not come across. After watching your video, TH-cam began to recommend me similar videos with cameras made according to this principle. Back in the fall, I bought a 50-liter propane cylinder with a wall thickness of 4mm. The perfect blank for such a camera. In January I will order waterjet cutting of metal for the lid and will weld myself a large chamber. And I wish you many years of life and remain as cheerful as in the video!
If people are going to weld their own anyway (because that's what people do) fill it with water first to test it and pressurise to at least 50% more than the working pressure, as water is incompressible it will stop the tank exploding and any leaks will be obvious.
@@RobertTolone TBH no pressure vessel is going to explode from a bit of dodgy welding, catastrophic failures need a lot more than that particularly at normal shop compressor pressures, leaks, certainly but not explosions. With your vessel worst that could happen if you were a SERIOUSLY bad welder is the front plate would blow off but you'd hear hissing of leaking air long before that and if your welding is that bad (very hard to be that bad) don't stand in front of the bit that's likely to fly off when testing it. There is a thing known as "Bar Litres" Also known as PS.V where you multiple the pressure by the volume and the bigger the number the worse the potential outcome in a failure. So a small vessel operating at relatively low pressure or even quite high pressure, no big deal but large vessel operating at even fairly low pressures could be bad, for context EU law defines "simple" pressure vessels as anything under 10,000 Bar litres, yours is about 200 Bar Litres at most I'd guess.
@@mfx1 A viewer wrote to me and asked if he could make a pressure pot out of a pickle jar. I told him that I did not recommend it. A guy who wanted to build a pot visited my shop and asked me how much pressure was in the pot. I told him, 50 psi. He said, wow - 50 pounds isn’t very much. I said, 50 pounds PER SQUARE INCH. That adds up to a hell of a lot of pressure on the walls of the pot. He had never heard of psi. This is what we are dealing with. I would rather exaggerates the dangers of welding a pressure vessel badly than underestimate them. 😃
Good suggestion Martin! You are right about people welding their own, I am one of them. I have modified a propane tank, which is only 4mm thick steel but rated to 22bar so in theory well over the spec for a 3 bar pressure pot. I want to stress test it at around 60 psi but not keen on doing so, however your water test sounds like a good option.
I suppose the cost of fabrication would depend your situation. If you sourced the parts from a truck junkyard and were competent to weld it yourself it would be very cheap. Or you might get a pricey quote from a fabricator.
Thank you for doing what you do. This is something I'm very interested in and I enjoy your videos immensely. I hope you have a great holiday season and I cant wait to see what you do next year!
Thank you for your prompt and courteous response. Unfortunately, I don’t get out of the house anymore (guess that may actually be a blessing with some many people getting ill these days) and it is almost two miles from the house to the nearest paved road, so unless Mz Liza is taking me to the V.A. (or buying food) she doesn’t get out much either. I hope you continue to have GREAT Success with your video series, and hopefully some day one of your faithful friends will create a Compact Disk set, so my grandchildren will have something to think about getting for their Granddad some Christmas. Sir, no matter how long we are going to have, Life will always be too short, so try to remember to have some fun Every Day! Stay healthy Be safe And teach people, their profession is how they will earn money during their life But all of us have the Same Job! Choosing how to spend the time we are given. If someone tells you to have a good day, happy holiday or enjoyable weekend. Turn around and tell them, “THAT’S MY JOB!” It is not about what work we do, It’s about How We CHOOSE To Live!” Wish I was a lot younger when someone told me that TRUTH! Da Gunny
Hey Robert, thank you so much for sharing all this information on your channel. I used to build large scale insect and scientific models for museeums. Now I changed to more technical stuff. It would have been great to have your knowledge 10 years ago - but I am so glad I came across your channel a month back. Take your well deserved christmas holiday. I am really curious to see your channel go further up in 21. Take care and thank you again from Düsseldorf, Germany Johnny
That is an old family joke. When I was in high school someone went down to a local store near my school and marked up all the Toblerone bars on the rack. Naturally, the store owner was furious and called my father. I told them I was not so stupid as to commit vandalism and leave my name all over the scene of the crime! Problem solved because my dad bought all the defaced bars in the store. I never did find out which “friend” did that to me! 😄
Please do a video on “Wax types and tools used” - I’m unable find “Sticky wax” online… just yellow sprue wax and the only ‘red’ wax I can find is for carving (can this be used to seal wood / plug holes?). Is yellow sprue wax okay to use w/silicon? I don’t think it has sulfur in it but it doesn’t say so on the box and I haven’t tried eating any yet. Also, it looks like you are using a Foredom wax carver - would you recommend anything cheaper? (I’m asking for a ‘friend’ who’s really poor). Are soy-based waxes okay to use? Soy seems cheaper. Apologies if you’ve already done a video on this topic - I wasn’t able to find it on your channel. The only wax related info on youtube and via gaagle is for metal / jewelry casting. Lastly (but should be firstly) - Thank you - your videos are informative, helpful and inspiring and I thank you for sharing your professional knowledge with us.
I get my sticky wax from www.freemanwax.com . It's caller Ferris Sticky Wax. There are many cheaper waxers out there but I have no personal experience with them. I blew out several waxers early in my career until I found the Foredom Wax Carver. (I wish they would sponsor me but I make no money from them). This one I use has lasted at least a decade. You have convinced me to do a wax video. I've been asked about wax even more than rubber or resin.
Robert, it’s a pleasure watching your channel and learning from you. I want to thank you for sharing your knowledge with everyone. Best regards, Richard.
Thank you! Would mounting a hook or bar to hang the lid on help, or maybe a rack up top to set it on? Having the specs makes it priceless. No guessing. Much appreciated for the detail!
I suppose it would. But we usually keep the lid inside the tank when it is not in active use. I don’t have specifications or plans for these tanks because they were fabricated from the brake cylinders of semi trucks. So the size of your tank would be dictated by the cylinder that you use. Any cylinder that can withstand up to 125 psi is suitable. The other reason I don’t provide specifications is that my tanks are homemade and I am not in any way qualified as an engineer. So I am really not in a position to provide design specs for pressure vessels. My tanks were fabricated for me by an expert welder and are massively overbuilt to compensate for the fact that I did not know how to specify a safe construction. We used very thick plate steel for the tank opening and doors.
@@RobertTolone I'm of the same school. If a large company spent tons of money engineering something and made plenty of them so they're cheap, it's a good way to go to be safe and get good technology affordably! Thank you for taking the time to answer!
Happy Holidays, Robert! Thanks for the great job on my base mold. I can’t wait to start casting some up for my projects. Stay safe and see you in the New a year!
Thanks for the video, Robert!! really love it it's such an innovative design were looking to make something similar here in the UK, So thankful to have found you as I've said before you house a wealth of knowledge in this field gained by years of trial and error!
Thanks for sharing this! Could you say what the seal on the lid is and how it is adhered? You cant imagine the issue of buying a replacement rubber gasket for my 2.5 gallon, paint pot in Canada. I drilled out and tapped the screw clamps on my pot and replaced the thumb screws with bolts so I could get a hard seal for the pressure I wanted to have, but tightening can be stressful before the resin starts to cure. I did buy a silent compressor this year which is magic (when you live in a condo). Is there a max pressure where it no longer makes a difference in the cast quality? Merry Christmas, Robert!
I am embarrassed to say that I don't remember. It is a very hard, solid tube of rubber; we cut them to length and glued the ends together and glued them into the grooves in the lid. My fabricator Bob supplied the tubing and the cement. After all these years I have not replaced any of these seals ever. I would try looking for O-Ring material or rubber tubing about as hard as a car tire. 70 Shore A, 40 Shore C or 25 Shore D. A rubber supplier should be able to recommend the appropriate adhesive for making the seal.
After all the videos I have seen of yours I just realized that this "pressure pot" system of yours is not a vacuum chamber but (duh) the opposite. I made a vacuum pot out of found parts to de-gas my silicone after mixing and it works very well for that but I thought you were casting resin in a vacuum too to avoid bubbles. I'm sure I've seen you de-gas rubber before but there must be a whole other reason to use pressure for casting and the distinction slipped past me somehow. Anyway, thanks for posting. Enjoy some time off and happy new year.
The main reason I use pressure is that I buy my resin in 5 gallon buckets. It takes quite a while to use up a bucket and no matter how carefully I seal the cap the resin absorbs moisture from the atmosphere over time. Even a tiny amount of moisture causes the resin to foam. Casting in a pressure pot prevents that foaming and will also remove the tiny bubbles that get incorporated into the resin when I fill the mold.
How did you make the lid exactly? Did it just get cut out of the steel plate that it goes into? What about the handle? Also why do you need 2 air compressors? Sorry for all the questions. I talked to someone I know about making one of these and he told me to research on where I can buy the lid. He said it looks like a concave lid.
i thought it was a vacuum chamber... that a vacuum would cause the bubbles to leave.. but your adding increased air pressure.. i wont argue with results if thats what works .. Can we do the molds without the chamber, i have this thing about catching shrapnel.
The pressure pot prevents the formation of bubbles that are the result of water vapor from the atmosphere. Urethane resin is very sensitive to moisture and will foam when it absorbs moisture from the air. The pressure pump will also remove small bubbles that may be trapped during the resin pour. It will not remove large bubbles. Those must be released from the mold with vents. I run my pressure pot at 50 PSI. The reservoir tank on the compressor is at 116 PSI. So even though the two tanks are roughly the same capacity there is plenty of air to quickly pressurize the casting chamber.
No, it is solid rubber tubing. I buy it off Amazon. The trick is to cut it exactly to length, clean, so that the ends meet perfectly. Then use some good all purpose adhesive. It’s important to glue the ends together but I don’t use much glue to hold the rubber into the channel in the door. The door seals itself as it closes.
Amazing videos Robert. I confess that I have just come across your channel and within 3 videos have subscribed. Great content, excellent tutorial skills. Unfortunately, I need to ask what may end up being an "I can't believe he asked that" kind of question. Sorry about that. I have had a very long interest in resin casting (with not much success) and watched many videos on the subject. When you come to the question of bubbles, I think I have almost always seem artists talk about using a vacuum chamber for bubble removal. You are the first I have seem that talks about using pressure vessels to do this. Is that because you are reducing rather than trying to remove the bubbles? Again, sorry for coming here with such a newbie question :-(
The primary use of the pressure pot is to suppress the formation of bubbles caused by absorption of atmospheric moisture into the resin. It takes awhile for me to use up my resin so it invariably absorbs moisture - which causes foaming. The pot will also compress small bubbles in the resin. By far the best way to make bubble free castings is to vent the cavity properly.
I am embarrassed to say that I don't remember. It is a very hard, solid tube of rubber; we cut them to length and glued the ends together and glued them into the grooves in the lid. My fabricator Bob supplied the tubing and the cement. After all these years I have not replaced any of these seals ever. I would try looking for O-Ring material or rubber tubing about as hard as a car tire. 70 Shore A, 40 Shore C or 25 Shore D. A rubber supplier should be able to recommend the appropriate adhesive for making the seal.
Robert Tolone thanks Robert and thanks again for all the advice in these videos. I think the key on the gasket is probably the groove. I tried to attach a butyl gasket to my lid with adhesive but the pressure just blew it sideways across the flat lid. I’ll have to have a groove machined in to resist that lateral force.
A valuable set of ideas here! Thank you. I will be making silicone molds for use in prototyping an automotive vent window seal. Can you tell me in the more black kind of rubber world is molding under pressure still useful? A Few months ago the cheapie compressor on top of our craftsman compressor died leaving behind a nice 30 gallon tank I hope to put to use like this as our molds will be larger than what you seem to be doing. Thank you for your great ideas!
@@RobertTolone from what I have heard is you have to vacuum silicone instead of using a pressure pot because the pressure pot doesn’t remove the air, it just makes the bubbles tiny, and since rubber/silicone is flexible as soon as you take it out of the pressure pot the bubbles re-expand which can deform your mold.
Could you please advise me on this matter? I am gonna buy the Iwata 850 Smart Jet Compressor, but I wonder if I can also use that tool for vacuum/pressure purposes? Or are those 2 different types of compression (the airbrush one maybe less psi?) Thanks!
I use a vacuum chamber to degas the rubber prior to pouring the mold. The pressure chamber is used to prevent bubbles when casting the resin in the mold.
@@annekabrimhall1059 Yes, and also a way to contain the resin above the mold as it rises and expands. Frankly, I never had very much luck vacuuming molds full of resin.
I've seen some pressure pots that use a vacuum to suck the air out (which brings all the bubbles up), and I've seen some like yours that pressurize to shrink the bubbles. Is there an advantage of one over the other?
They have different purposes. and there are advantages and disadvantages to both. Vacuum Chambers are better at getting rid of bubbles as they are literally taking all the air out of the chamber completely. BUT they are slower. so if you tried to use resin in a Vacuum chamber (depending on the resin) it would cure mid degassing it. Pressure pots as you know only shrink the air to be (for the most part) undetectable to the human eye. but still there none the less. BUT pressure pots are WAY more dangerous than vacuum chambers. if a vacuum chamber breaks mid use it will simply seize to work. If a Pressure pot breaks mid use, you will die. they are very dangerous.
@@RobertTolone most get a Harbor Freight paint pot, strip off all the plumbing and just have a gauge, pop off valve and fill connection with valve. For the hobbyist it much more accessible than your welded tanks. I only run max 50 PSI. They are more prone to leaks than your system since the pressure doesn't hold the door sealed. Some also use ones from I think California Air that may already be setup but they are all paint pots.
Your videos are incredible, thanks so much! How would you approach minimizing bubbles if casting a large object, say 24 x 24" x 5"? Would you use vibration or some other alternative to pressure pot? Or try to fabricate a vessel with an opening that large?
if you are regularly casting objects of that size it would pay for itself to fabricate a pressure pot. But you would really have to get your engineering right so that the pot is safe to use. I have never had much luck with vibration for removing bubbles. You could use fresh resin that has no moisture absorbed into it and use compressed air to blow out bubbles if the mold is an open-back kind.
Thanks for your reply! I only plan to cast this one large object, but I'll hopefully be making 50+ pieces. I guess I'll give it a go without pressure and see how I do, then reconsider whether I need to fabricate a ginormous tank.
As soon as I saw this , and wondered about the pressure inside , I thought 4 threaded rods with nuts, holding the back to the front would be a pretty good safety backup . ? what do you all think ?
Yes, I’ve see tanks with that design. Any safety improvement is a good idea. When I had the tanks made I was assured that the weld strength was more than adequate for the pressures I was operating the tank at. Nonetheless I developed the habit of walking away from the tank as soon as the door sealed and before the pressure maxed in the tank. I didn’t want to be standing right in front in case it blew open! 😳😄 Another good safety would be to have a check valve that opened at 80 psi. The truck tanks operate at a significantly higher pressures than that.
@@RobertTolone yes , I'm thinking of using a small air compressor tank I kept , as it would be usefull one day ! lol .. I'm completely new to silicone/resin , and as most new people do , I've bought a liter of both BEFORE I decide what to make (try) :-) . I'm finding your chanel very useful . thank you
I don’t know. But it’s much thinner than 1/2 inch. We used semi truck brake cylinders and they operate at higher pressures than I run my tanks at. So we figured they were safe. The must be specifications somewhere mandating wall thickness according to cylinder size and operating pressure.
![ลองสั่งของจากแอพ temu ถูกจริงหรอ?? ( part : 1/2 ) [โกงไหมครับ ep.89 ] | DOM](http://i.ytimg.com/vi/RTcZSQTiDZw/mqdefault.jpg)
![[UNCUT]"ตุลามรณะ"ย้อนฟังคำทำนาย หมอดูทุกสาย ดวงเมืองร้อน (หมอปลาย ฟองสนาน อ.โอเล่)I คนดังนั่งเคลียร์](http://i.ytimg.com/vi/lE5az5VvT9M/mqdefault.jpg)
Enjoy your break, Bob! Looking forward to seeing you again in the new year!
Thanks Jason, see you next year!
Thanks Robert! A well-deserved break! But, I know you aren’t relaxing!
awesome! glad I finally found this video.
Have a great holiday! see ya next year.
Happy holidays Jerry!
I was literally researching this at the time of this posting. We just had a metal failure on our HFT pressure tank 10 minutes prior. The clamps aren't ideal for quick insertion into pressure for our quick-cure applications. Thanks for posting!!!
Yes, it is very hard to seal the tank fast enough to cast quick curing resins.
I recently discovered your channel and the info you provide is priceless. I just poured my first mold the other day and it turned out perfectly with zero imperfections, i was so happy. I cast both wax and chocolate Santa's with it. I so wanna do this more now lol. On a side note I could see maybe modifying your tank to have internal guide rails on the inside of the front face for the lid to loosely slide flush either vertically or horizontally so the chamber wouldn't have to be so deep and so you wouldn't have to store the lid separately. It would probably be a involved modification tho. Idk im not an expert i just love technology of all sorts and wanna make everything.
Thank you Robert!!! Merry Christmas!!!!
Thanks for watching Tactical! See you next year!
sounds like you really need a break / vacation! have a MERRY CHRISTMAS and HAPPY HOLIDAYs!!!! see ya when you get back!!!
Thanks! You too Yooper!
The design is so simple and ingenious.
It closes by itself and you don't need a bunch of bolts to close it.
I realy love it.
See you next year and have a nice Christmas !
I wish I had thought it up. But someone told me that doors on submarines are designed so that if a compartment floods it pushes the doors closed.
Really enjoy and appreciate your videos. Enjoy your break!
Thanks David, will do!
Thanks for the videos! Merry christmas!
Thank you too!
Yuss! Was wondering the same. Figured it was home made ! Good stuff!
I've been admiring your pressure chamber since I've started watching your videos. I noticed the oval door because that's why manhole covers are round, so they don't drop in. This design is super fast and easy to handle and I love it. I also love the touch of having a muffler for the air release valve. I always have to cover my ears for that, but strangely never thought to use a muffler.
Retrospect viewer
Find your pace... tune that pace.
Tune in time off the best you can.
🍀😎🤜🏼🤛🏼🤓💫
Happy holidays.
Same to you!
superb advice
50 PSI pressure are around 3.5 bar. As such, air bubbles in castings become 3.5 times smaller in size when pressurized inside the pot (since earths atmosphere is around 1 bar of pressure at sea level). So, the more pressure inside the pot, the smaller the size of the resulting bubble. Lets of course not forget that a car tire has around 2.2 bar pressure and you can easily understand how this thing exploding can deliver vast amounts of terror! :)
Merry Christmas Robert! Can't wait for your next videos!
You explained perfectly why the pressure pot will effectively eliminate small bubbles but not big ones. My tanks are safe up to 125 PSI, but I have found it is not necessary to run them at higher than 50. But I went the air from the mold, not crush it out.
@@RobertTolone It seems normal that you don't run them higher than 50 PSI. If you take a 1cc bubble and pressurize it at 2 bar (1 bar on the gauge), the size of it will become 0.5cc. If you continue compressing it at 3 bar, the size of it will become 0.33cc. So, the change in size is only by 0.17cc compared to the 0.5cc of the initial compression. At the end, you compress it more but the size changes very little.
Just for information. Scuba divers have higher risk when surfacing from 10m depth (2 bar) to the sea level than from 20m depth (3 bar) to 10m depth as the bubbles in their blood stream doubles when going from 10m to 0.
@@ekalyvio Great information. Thanks for sharing!
enjoy these days!! I will be waiting for your next video for sure! take care!!! :)
Thank Rob, enjoy the rest.
Thanks for all your hard work,love your channel
My pleasure Brandon, thanks!
Enjoy your break, happy holidays to you! Thanks for the details on the pressure pot, definitely a genius design.
Thanks Jonny! Happy Holidays to you!
Thanks Robert
I have a pressure cooker that uses the same oval lid design. It's so reassuring to know that the pressure is safely contained.
Have a great break. Happy Holidays.
It's so much better than the bolt-down style of pressure pots. Cheers!
Thanks Robert, have a fantastic Christmas mate👍👍
You too Drew, Thanks!
Happy Holidays! Enjoy your break!
Thanks MsBlis! Happy Holidays to you too!
A well deserved break! Congratulations on your smash successful year!
Thank you Anne! ♥♥♥
Thank you.
Well, this is a welcome video! Thank you sir!
Glad you enjoyed it!
Have a good break, you've earned it!
Thanks, Dane!
Love the video. You're relaxing to listen to.
Glad you enjoyed Brandon!
Love your videos, Enjoy your Christmas break.
Thank you! You too!
It’s a work of art! Thanks for sharing the info.
Great video as usual, thanks for educating and entertaining us, have a wonderful holiday, looking forward to seeing you next year...
Thanks Paul, Same to you!
Happy holidays! enjoy your break!
Thank you Perry! Will do!
Thank you for this and all your previous efforts. Friday the 8th january I am hiding my face in tears - Merry chrisman and a happy new year to you and all your family ....
Thanks for watching and for all your comments Wolli! See you in the new year.
Merry Christmas Robert! Can't wait for your next videos!
More to come Lasse! Thanks for watching!
As a pressure welder, I was just thinking about getting the material together to make myself a few of these just earlier today and lo and behold, your video on this drops. What serendipity! Many thanks for your videos, you must be a fantastic person to apprentice under. Have an amazing holiday season Robert, and I hope you a healthy and safe new years.
Soon you'll be selling them on Amazon!
@@RobertTolone Hah! Looking to only do as much work as I have to to play hard, not looking for more work ;)
Thank you for the Channel. Merry Christmas and an wonderfull 2021.
Thanks Eugênio!
if you rotate lid handle 90 degrees you can put lid in, taking less space inside.
Merry Christmas! Have a wonderful rest of the year.
Thanks Joe. Same to you!
Hi Robert! I am writing to you from Ukraine. I have long wanted to make such a camera, but the simplest version of manufacturing did not come across. After watching your video, TH-cam began to recommend me similar videos with cameras made according to this principle. Back in the fall, I bought a 50-liter propane cylinder with a wall thickness of 4mm. The perfect blank for such a camera. In January I will order waterjet cutting of metal for the lid and will weld myself a large chamber. And I wish you many years of life and remain as cheerful as in the video!
Good luck with your build. Let us know how it works for you.
Happy holidays Robert! Thank you for sharing all that knowledge!!
Same to you Yugos!
If people are going to weld their own anyway (because that's what people do) fill it with water first to test it and pressurise to at least 50% more than the working pressure, as water is incompressible it will stop the tank exploding and any leaks will be obvious.
Good safety check!
@@RobertTolone TBH no pressure vessel is going to explode from a bit of dodgy welding, catastrophic failures need a lot more than that particularly at normal shop compressor pressures, leaks, certainly but not explosions. With your vessel worst that could happen if you were a SERIOUSLY bad welder is the front plate would blow off but you'd hear hissing of leaking air long before that and if your welding is that bad (very hard to be that bad) don't stand in front of the bit that's likely to fly off when testing it. There is a thing known as "Bar Litres" Also known as PS.V where you multiple the pressure by the volume and the bigger the number the worse the potential outcome in a failure. So a small vessel operating at relatively low pressure or even quite high pressure, no big deal but large vessel operating at even fairly low pressures could be bad, for context EU law defines "simple" pressure vessels as anything under 10,000 Bar litres, yours is about 200 Bar Litres at most I'd guess.
@@mfx1 A viewer wrote to me and asked if he could make a pressure pot out of a pickle jar. I told him that I did not recommend it. A guy who wanted to build a pot visited my shop and asked me how much pressure was in the pot. I told him, 50 psi. He said, wow - 50 pounds isn’t very much. I said, 50 pounds PER SQUARE INCH. That adds up to a hell of a lot of pressure on the walls of the pot. He had never heard of psi. This is what we are dealing with. I would rather exaggerates the dangers of welding a pressure vessel badly than underestimate them. 😃
Good suggestion Martin! You are right about people welding their own, I am one of them. I have modified a propane tank, which is only 4mm thick steel but rated to 22bar so in theory well over the spec for a 3 bar pressure pot. I want to stress test it at around 60 psi but not keen on doing so, however your water test sounds like a good option.
Thank you for all of the fantastic, educational content. Happy Holidays!
Same to you Christopher!
@@RobertTolone Thank you, Mr. Tolone.
You are very generous to share that with us. Thank You. I only wish we could talk about the relative cost to have pressure pots made, VS buying them?
I suppose the cost of fabrication would depend your situation. If you sourced the parts from a truck junkyard and were competent to weld it yourself it would be very cheap. Or you might get a pricey quote from a fabricator.
Merry Christmas, thanks for the videos and look forward to 2021!
Merry Christmas and I'll see you next year!
Thank you, and happy holidays!
Happy Christmas Robert. thanks for the great videos and looking forward to seeing more next year.
Thanks for watching and commenting Security!
Thank you so much for walking through your design for the pressure pot. I really enjoyed it. We'll see you again next year.
Hey Robert, I just want to thank you for your amazing videos, they've helped with my own projects so much! Keep up the great work 👍
🙏 happy holiday master!
Thank you for doing what you do. This is something I'm very interested in and I enjoy your videos immensely. I hope you have a great holiday season and I cant wait to see what you do next year!
Thanks for watching!
Thank you for your prompt and courteous response.
Unfortunately, I don’t get out of the house anymore (guess that may actually be a blessing with some many people getting ill these days) and it is almost two miles from the house to the nearest paved road, so unless Mz Liza is taking me to the V.A. (or buying food) she doesn’t get out much either.
I hope you continue to have GREAT Success with your video series, and hopefully some day one of your faithful friends will create a Compact Disk set, so my grandchildren will have something to think about getting for their Granddad some Christmas.
Sir, no matter how long we are going to have, Life will always be too short, so try to remember to have some fun Every Day!
Stay healthy
Be safe
And teach people, their profession is how they will earn money during their life
But all of us have the Same Job!
Choosing how to spend the time we are given.
If someone tells you to have a good day, happy holiday or enjoyable weekend. Turn around and tell them, “THAT’S MY JOB!”
It is not about what work we do, It’s about How We CHOOSE To Live!”
Wish I was a lot younger when someone told me that TRUTH!
Da Gunny
👍
Thanks for sharing your knowledge, have a good break
Thanks Bruno!
Hey Robert,
thank you so much for sharing all this information on your channel. I used to build large scale insect and scientific models for museeums. Now I changed to more technical stuff. It would have been great to have your knowledge 10 years ago - but I am so glad I came across your channel a month back.
Take your well deserved christmas holiday. I am really curious to see your channel go further up in 21.
Take care and thank you again from Düsseldorf, Germany
Johnny
Thanks Johnny!
The Toblerone on the tool rack had me cracking up
That is an old family joke. When I was in high school someone went down to a local store near my school and marked up all the Toblerone bars on the rack. Naturally, the store owner was furious and called my father. I told them I was not so stupid as to commit vandalism and leave my name all over the scene of the crime! Problem solved because my dad bought all the defaced bars in the store. I never did find out which “friend” did that to me! 😄
thank you for all your efforts in producing these videos and keeping up the pace ! enjoy your breake, and stay safe
Happy Christmas
Thanks for all the videos look forward to seeing you in the new year
J
Happy holidays Jordan!
Please do a video on “Wax types and tools used” - I’m unable find “Sticky wax” online… just yellow sprue wax and the only ‘red’ wax I can find is for carving (can this be used to seal wood / plug holes?). Is yellow sprue wax okay to use w/silicon? I don’t think it has sulfur in it but it doesn’t say so on the box and I haven’t tried eating any yet.
Also, it looks like you are using a Foredom wax carver - would you recommend anything cheaper? (I’m asking for a ‘friend’ who’s really poor). Are soy-based waxes okay to use? Soy seems cheaper.
Apologies if you’ve already done a video on this topic - I wasn’t able to find it on your channel. The only wax related info on youtube and via gaagle is for metal / jewelry casting.
Lastly (but should be firstly) - Thank you - your videos are informative, helpful and inspiring and I thank you for sharing your professional knowledge with us.
I get my sticky wax from www.freemanwax.com . It's caller Ferris Sticky Wax.
There are many cheaper waxers out there but I have no personal experience with them. I blew out several waxers early in my career until I found the Foredom Wax Carver. (I wish they would sponsor me but I make no money from them). This one I use has lasted at least a decade.
You have convinced me to do a wax video. I've been asked about wax even more than rubber or resin.
Enjoy your time off Robert! Looking forward to all the cool stuff you will share in 2021. Happy holidays.
Thanks Larry!
Thank you, Robert!
Thanks for the great content, Robert. I've learned so many new tips to use for casting and mold making- you're a true legend 🙌
Thanks for watching!
Robert, it’s a pleasure watching your channel and learning from you. I want to thank you for sharing your knowledge with everyone. Best regards, Richard.
Thanks so much for watching Richard.
Huh, that's a plug-type door just like the L-1 door on the Boeing 767 freighter! ^_^
I was told they’re the kind of doors they have on submarines.
@@RobertTolone makes way more sense ^_^ Love your channel, your teaching and message that everyone can do this!
Thanks for all the videos, Roger. Enjoy your time off, merry christmas and a happy new year. =)
Merry Christmas to you too Roger!
Thank you! Would mounting a hook or bar to hang the lid on help, or maybe a rack up top to set it on? Having the specs makes it priceless. No guessing. Much appreciated for the detail!
I suppose it would. But we usually keep the lid inside the tank when it is not in active use. I don’t have specifications or plans for these tanks because they were fabricated from the brake cylinders of semi trucks. So the size of your tank would be dictated by the cylinder that you use. Any cylinder that can withstand up to 125 psi is suitable. The other reason I don’t provide specifications is that my tanks are homemade and I am not in any way qualified as an engineer. So I am really not in a position to provide design specs for pressure vessels. My tanks were fabricated for me by an expert welder and are massively overbuilt to compensate for the fact that I did not know how to specify a safe construction. We used very thick plate steel for the tank opening and doors.
@@RobertTolone I'm of the same school. If a large company spent tons of money engineering something and made plenty of them so they're cheap, it's a good way to go to be safe and get good technology affordably! Thank you for taking the time to answer!
Happy Holidays, Robert! Thanks for the great job on my base mold. I can’t wait to start casting some up for my projects. Stay safe and see you in the New a year!
Your project was very popular! It was a lot of fun for me to do. Hope you have a happy holiday season. See you next year!
Thanks for the video, Robert!! really love it it's such an innovative design were looking to make something similar here in the UK, So thankful to have found you as I've said before you house a wealth of knowledge in this field gained by years of trial and error!
Thanks Luke!
Happy Holidays
Same to you!
Thank you very much too sir,
Thanks so much for watching!
Mocking hysterical mothers is timeless
Thanks for sharing this! Could you say what the seal on the lid is and how it is adhered? You cant imagine the issue of buying a replacement rubber gasket for my 2.5 gallon, paint pot in Canada.
I drilled out and tapped the screw clamps on my pot and replaced the thumb screws with bolts so I could get a hard seal for the pressure I wanted to have, but tightening can be stressful before the resin starts to cure. I did buy a silent compressor this year which is magic (when you live in a condo). Is there a max pressure where it no longer makes a difference in the cast quality? Merry Christmas, Robert!
I am embarrassed to say that I don't remember. It is a very hard, solid tube of rubber; we cut them to length and glued the ends together and glued them into the grooves in the lid. My fabricator Bob supplied the tubing and the cement. After all these years I have not replaced any of these seals ever. I would try looking for O-Ring material or rubber tubing about as hard as a car tire. 70 Shore A, 40 Shore C or 25 Shore D. A rubber supplier should be able to recommend the appropriate adhesive for making the seal.
After all the videos I have seen of yours I just realized that this "pressure pot" system of yours is not a vacuum chamber but (duh) the opposite. I made a vacuum pot out of found parts to de-gas my silicone after mixing and it works very well for that but I thought you were casting resin in a vacuum too to avoid bubbles. I'm sure I've seen you de-gas rubber before but there must be a whole other reason to use pressure for casting and the distinction slipped past me somehow. Anyway, thanks for posting. Enjoy some time off and happy new year.
The main reason I use pressure is that I buy my resin in 5 gallon buckets. It takes quite a while to use up a bucket and no matter how carefully I seal the cap the resin absorbs moisture from the atmosphere over time. Even a tiny amount of moisture causes the resin to foam. Casting in a pressure pot prevents that foaming and will also remove the tiny bubbles that get incorporated into the resin when I fill the mold.
hi robert, how did it go with the snow globe? you keeping us on a cliffhanger there.. 😜
It took FOREVER to get the resin delivered but it finally came in. You'll see the Snow Globe video on Jan 8th 2021.
How did you make the lid exactly? Did it just get cut out of the steel plate that it goes into? What about the handle? Also why do you need 2 air compressors? Sorry for all the questions. I talked to someone I know about making one of these and he told me to research on where I can buy the lid. He said it looks like a concave lid.
I have a question for you I'm guessing you had the door machined for the seal but what kind of seal did you use did make you make a custom one?
Can I create a room like this and still draw air? All I have to do is replace the piston?
i thought it was a vacuum chamber... that a vacuum would cause the bubbles to leave.. but your adding increased air pressure.. i wont argue with results if thats what works .. Can we do the molds without the chamber, i have this thing about catching shrapnel.
The pressure pot is mainly used to prevent foaming that happens when resin absorbs moisture from the atmosphere.
Excellent Information. What does the pressure do to the resin. Will this work on all resin castings. How many horse power is the compressor? thanks
The pressure pot prevents the formation of bubbles that are the result of water vapor from the atmosphere. Urethane resin is very sensitive to moisture and will foam when it absorbs moisture from the air. The pressure pump will also remove small bubbles that may be trapped during the resin pour. It will not remove large bubbles. Those must be released from the mold with vents. I run my pressure pot at 50 PSI. The reservoir tank on the compressor is at 116 PSI. So even though the two tanks are roughly the same capacity there is plenty of air to quickly pressurize the casting chamber.
I'm curious as to how you made the seal on the door. Is it silicone ? Any info will be appreciated. Great channel by the way. God Bless !
No, it is solid rubber tubing. I buy it off Amazon. The trick is to cut it exactly to length, clean, so that the ends meet perfectly. Then use some good all purpose adhesive. It’s important to glue the ends together but I don’t use much glue to hold the rubber into the channel in the door. The door seals itself as it closes.
@@RobertTolone Thanks for the reply. I have a couple of big casting projects and need to build a pressure pot. Love the videos, Thanks
I hope you're told enough what a gift you are and more so for bothering to make these videos. I've learned a lot!
Thanks Sarah, I appreciate it very much.
Amazing videos Robert. I confess that I have just come across your channel and within 3 videos have subscribed. Great content, excellent tutorial skills. Unfortunately, I need to ask what may end up being an "I can't believe he asked that" kind of question. Sorry about that. I have had a very long interest in resin casting (with not much success) and watched many videos on the subject. When you come to the question of bubbles, I think I have almost always seem artists talk about using a vacuum chamber for bubble removal. You are the first I have seem that talks about using pressure vessels to do this. Is that because you are reducing rather than trying to remove the bubbles? Again, sorry for coming here with such a newbie question :-(
The primary use of the pressure pot is to suppress the formation of bubbles caused by absorption of atmospheric moisture into the resin. It takes awhile for me to use up my resin so it invariably absorbs moisture - which causes foaming. The pot will also compress small bubbles in the resin. By far the best way to make bubble free castings is to vent the cavity properly.
The gasket Robert, what’s the gasket!? I’ve replicated this setup almost exactly but I can’t get the seal to stay in place
I am embarrassed to say that I don't remember. It is a very hard, solid tube of rubber; we cut them to length and glued the ends together and glued them into the grooves in the lid. My fabricator Bob supplied the tubing and the cement. After all these years I have not replaced any of these seals ever. I would try looking for O-Ring material or rubber tubing about as hard as a car tire. 70 Shore A, 40 Shore C or 25 Shore D. A rubber supplier should be able to recommend the appropriate adhesive for making the seal.
Robert Tolone thanks Robert and thanks again for all the advice in these videos.
I think the key on the gasket is probably the groove. I tried to attach a butyl gasket to my lid with adhesive but the pressure just blew it sideways across the flat lid. I’ll have to have a groove machined in to resist that lateral force.
@@Mafdark1 Yes, you need to mill that groove.
How much did it cost to make? I love this design.
I didn’t me cost much because we scrounged the surplus brake cylinder and steel and my then father-in-law did the fabrication and welding.
A valuable set of ideas here! Thank you. I will be making silicone molds for use in prototyping an automotive vent window seal. Can you tell me in the more black kind of rubber world is molding under pressure still useful? A Few months ago the cheapie compressor on top of our craftsman compressor died leaving behind a nice 30 gallon tank I hope to put to use like this as our molds will be larger than what you seem to be doing. Thank you for your great ideas!
I can’t speak to that from experience but it seems to me that pressure counseling would work just as well with rubber as it does in resin.
@@RobertTolone from what I have heard is you have to vacuum silicone instead of using a pressure pot because the pressure pot doesn’t remove the air, it just makes the bubbles tiny, and since rubber/silicone is flexible as soon as you take it out of the pressure pot the bubbles re-expand which can deform your mold.
@@plantlover5978 If you leave the silicone in the pressure pot until it is cured then the bubbles will not re-expand.
thank you for you videos, also where is the best place to get the rubber mold making and resin?
I buy my casting materials from www.silpak.com. Searching online is the easiest way to compare prices from various suppliers.
Could you please advise me on this matter? I am gonna buy the Iwata 850 Smart Jet Compressor, but I wonder if I can also use that tool for vacuum/pressure purposes? Or are those 2 different types of compression (the airbrush one maybe less psi?) Thanks!
Excuse my ignorance but I thought people used a vacuumed chamber to degas the castings.
I use a vacuum chamber to degas the rubber prior to pouring the mold. The pressure chamber is used to prevent bubbles when casting the resin in the mold.
What kind of castings are not put into the tank?
Everything else than rotate casting?
A negative pressure degasser is cheaper and easier to build. Would it help at all to pull the bubbles out of the resin?
I find it doesn't work with the resins I use because they set up too fast. The resin gels while it's still foaming under vacuum.
@@RobertTolone so you would need a slow setting resin.
@@annekabrimhall1059 Yes, and also a way to contain the resin above the mold as it rises and expands. Frankly, I never had very much luck vacuuming molds full of resin.
So far I only use resin when I make jewelry. I just hit it with the heat gun for one second and it pops the bubbles.
thank you for the pressure pot info and the 50 psi setting. do you use more than 50 psi and for what reason?
Sometimes as much as 80 psi. It can help eliminate small stubborn bubbles. But proper venting of the mold is always the best remedy for bubbles.
What about vacuum Chambers?
Don't be like that please. I know the globe made you angry. I would love to hear you sing again soon :)
I've seen some pressure pots that use a vacuum to suck the air out (which brings all the bubbles up), and I've seen some like yours that pressurize to shrink the bubbles. Is there an advantage of one over the other?
They have different purposes. and there are advantages and disadvantages to both.
Vacuum Chambers are better at getting rid of bubbles as they are literally taking all the air out of the chamber completely. BUT they are slower. so if you tried to use resin in a Vacuum chamber (depending on the resin) it would cure mid degassing it.
Pressure pots as you know only shrink the air to be (for the most part) undetectable to the human eye. but still there none the less. BUT pressure pots are WAY more dangerous than vacuum chambers. if a vacuum chamber breaks mid use it will simply seize to work. If a Pressure pot breaks mid use, you will die. they are very dangerous.
Hello Robert, can you please tell what is the dimensions of the pipe ? or what the volume of it ?
No talk about using a paint pot? Thats what I use.
Oh and cue sad clown music, no rotary casting until next year. 😭
I've never used a paint pot to pressure cast so I'm not qualified to talk about them.
@@RobertTolone most get a Harbor Freight paint pot, strip off all the plumbing and just have a gauge, pop off valve and fill connection with valve. For the hobbyist it much more accessible than your welded tanks. I only run max 50 PSI. They are more prone to leaks than your system since the pressure doesn't hold the door sealed.
Some also use ones from I think California Air that may already be setup but they are all paint pots.
@@chartle1 That is definitely the route that most people seem to go.
Question about the blue material you use for '' venting '' ,where do you get it? Thank You sit
Those are wax wires from www.freemanwax.com. They are also called sprue wax and are commonly sold by jewelry making supply companies.
Your videos are incredible, thanks so much! How would you approach minimizing bubbles if casting a large object, say 24 x 24" x 5"? Would you use vibration or some other alternative to pressure pot? Or try to fabricate a vessel with an opening that large?
if you are regularly casting objects of that size it would pay for itself to fabricate a pressure pot. But you would really have to get your engineering right so that the pot is safe to use. I have never had much luck with vibration for removing bubbles. You could use fresh resin that has no moisture absorbed into it and use compressed air to blow out bubbles if the mold is an open-back kind.
Thanks for your reply! I only plan to cast this one large object, but I'll hopefully be making 50+ pieces. I guess I'll give it a go without pressure and see how I do, then reconsider whether I need to fabricate a ginormous tank.
As soon as I saw this , and wondered about the pressure inside , I thought 4 threaded rods with nuts, holding the back to the front would be a pretty good safety backup . ? what do you all think ?
Yes, I’ve see tanks with that design. Any safety improvement is a good idea. When I had the tanks made I was assured that the weld strength was more than adequate for the pressures I was operating the tank at. Nonetheless I developed the habit of walking away from the tank as soon as the door sealed and before the pressure maxed in the tank. I didn’t want to be standing right in front in case it blew open! 😳😄
Another good safety would be to have a check valve that opened at 80 psi. The truck tanks operate at a significantly higher pressures than that.
@@RobertTolone yes , I'm thinking of using a small air compressor tank I kept , as it would be usefull one day ! lol .. I'm completely new to silicone/resin , and as most new people do , I've bought a liter of both BEFORE I decide what to make (try) :-) . I'm finding your chanel very useful . thank you
How thick is the metal of the cylinder section? Half inch like the front?
I don’t know. But it’s much thinner than 1/2 inch. We used semi truck brake cylinders and they operate at higher pressures than I run my tanks at. So we figured they were safe. The must be specifications somewhere mandating wall thickness according to cylinder size and operating pressure.