Casey, you have helped me immensely. Great information and very succinct . I just purchased Alumilite products and "0" experience . I purchased a harbor freight 7x12 mini lathe for hopefully the best of two worlds. So, pressure pot with Alumilite. Thx. Will stay tuned , oh, I will be making pens and wife arts and crafts. Our retirement plan. Your great, thanks.
Diminishing returns from higher pressures. I've seen casting recommendations from 40-60psi. It's more a function of resin viscosity and mold material. Too little pressure with a viscous resin and complex mold and you may not compact the bubbles enough or fill the voids. Too much pressure and you may distort the mold. Which is also why molds should always be made from pressure-safe materials.
I know this is a 2 year old video but wanted to add my two cents all the same. Pressure pots do not shrink bubbles. It actually increases the pressure which forces the air out of liquid inside it. Think of it as pressing in on all sides equally. It is like wringing out a sponge when squeezed. The molded resin needs to be inside and pressurized until the epoxy resin solidifies to keep air bubbles from reforming once pressure is reduced. I do use the Harbor Freight modified pressure pot. If you spin/twist the slotted face plate on the pressure relief valve (not the stem you pull to release pressure) it will increase or decrease the pressure relief setting. Now, the HF pots do tend to need resealing every fitting with teflon tape or liquid teflon seal. My tank will leak from the rim until it comes up to pressure. I have a mark on the lid over the leak prone area to remind me. So, if it leaks elsewhere I need to check it out. A good even slathering of Vaseline on the entire seal will help seal it. We used that same trick on pneumatic aircraft systems tubing joints and o-rings to seal out leaks. The pressure pot seal under the lid is just a large o-ring. One more thought, my seal was installed at factory upside down causing leakage no matter what I did to improve it. After I reversed it the pot sealed once it pressurized above 27psi. Now, we are talking about a HF product and my fixes may not be typical. I do keep my air pressure line hooked up and under pressure while curing in case of leakage. It helps when your compressor is very quiet when running. Also, if I do hear my compressor running a lot I know I have a problem. I hope this helps someone else. Unfortunately, you will have to use your tank and test out how long to let your resin remain pressurized. It all comes down to volume of resin, temperature, resin cure/de-mold times, elevation, and barometric pressure to get an accurate pressurized time. I am not a scientist with a degree if physics and environmental science. I am a wood turner with a college experience that taught me one thing. Put it in the pot, pressurize it, uncork it 12-24 hours later and hope it did the job...
Thanks! I've watched a ton of these videos (planning on trying resin casting for the first time) and they all talk about the bubbles shrinking. It has never made sense to me. If it were true, the resin would become full of microscopic highly pressurised pockets of air, and it would explode prince rupert's drop style when the pressure in the pot got released.
Thank you Casey, the reason I asked is most people seem to leave over night and to be sure of maintaining the pressure that long I would need to leave my compressor on. Thank you again, I am in the UK
Unless you have a workshop fitted with air lines all over your barn (my problem multiple air leaks), leaving the compressor hooked up would never be a problem, The compressor would cycle only 1 or 2 in 24 hours, if you had a real small leak.
TY for the video. Have you tried to reverse the center bolt and screw it in from the inside? If there is enough shoulder space, use a thick washer made of a softer metal (e.g. brass, copper or alum) that can conform to the shoulder surface when torquing the bolt down, but also have it doubled up with a hardened steel washer to avoid cracking the softer washer. A sealant made for engine head gaskets would be recommended as well. I'd only use Loctite on the surface area where the bolt and the nut are mating but not anywhere else. Loctite and similar products are designed to keep a bolt in place; they're not designed for sealing. It couldn't hurt to use the same washer/sealant method on the outside either.
What if you are losing MORE than 1 psi? I have a leak at the joint under the gauge. I’ve taken it apart, wrapped the threads with Teflon tape, added a liquid thread sealer to the threads, and reinstalled but still leaking. Can you stop a slow leak without taking it apart again? Like maybe using hot glue or something similar?
It depends on if it loses enough to be lower than 45 psi or so after several hours. If you’re using alumilite and the leak is small enough that it stays above 45 psi for 3 hours, it’s fine. You can’t really add something like that to seal it that easily. I’d just buy another gauge.
I'm having an issue with the pressure relief valve. It's supposed to open at 60 psi, but seems to be set at more like 45 psi. It continues to bleed pressure to about 45 psi. Is there a swap-out valve for this, or is it adjustable?
Hi, I have just bought the larger blue pot you have but haven’t used it yet, how long should I leave it pressurised for with the resin in it? Thanks Michael
Depends on the resin my friend, but I usually keep Alumilite in there for 2.5-3.5 hours with my ambient temperature here in California. Definitely do longer if it’s cold where you are or during winter. I would recommend cutting or turning only after 3-3.5 hours though
Hello. Does every casting need to be placed in a pressure pot or just items used with certain resins? I watched many casting videos; but there is no clear answer. I thank you for any help_ advice/ explanation you give.
I have seen multiple people do it. It’s mainly to accommodate longer molds. If you ever did have a pot malfunction though, it’d be much safer having the lid burst off up, rather than towards something. However the best I saw was a large Binks pressure pot (type I’d feel safest doing it with), and the guy put a shelf or two inside of it, so he could fill multiple shelves with molds
Twist it. Right will tighten, lowering the safety PSI, left will loosen, and raise the safety PSI. Depending on your pot you might need a screw driver to twist it, or you might be able to with just your fingers or a wrench.
I have a hf pressure pot and modded it pretty well I'd say for my first time it held 50 psi for about 24 hour more than needed but I overtightened a T fitting and cracked and I had to reduce it now I can't get it to hold pressure for 4 hours it reduces to 30 idk what I did wrong someone help?
Did you strip the threads? If not then just get a new fitting. Since hardware stores are closed order one online. Maybe a local hardware store has a curbside pickup though
Thank you so much for the information! It seems like my local Harbor Freight doesn't carry the pressure pots for some reason... It looks as if I'm going to have to buy mine online! Many blessings to you!
@AdamWayneone My local harbor freight store does not carry the paint pot. No free "ship to store" option if bought online. I contacted harbor freight customer service and they said they would consider adding free ship to store in the future.
One fix for the hole on top would be to take it to a local welding shop and have a round plate welded around it. No bolt needed and no inner bulk from the bolt and zero leaks.
I am thinking about getting the blue one how do you release the air pressure. I saw the other video and it looked like you put a plug in where the release valve is. I might have missed something. Thank you.
I have two of them and it all has to do with replacing the factory seal on most of the bolts. Did you take out the safety valve? What I have done is basically unthreaded every single component that goes into the lid, and retreaded everything that’s necessary with new thread sealant, and plugged the ones that aren’t with new sealant too.
If you use it as a vacuum chamber, yes. Using pressure won’t work because as soon as the pressure is released the juice comes out of the wood it was being pressurized into. It’d only work if you could cure it under pressure
+Chris Sammons The resin doesn’t cure in a few minutes, it takes about 36 hours for a full cure. The demold time accoridng to the manufacture is 90 minutes, but that is only with a 100g mass, and mine are typically 300g or so, which is why I wait about 4 hours. I have waited about 2 hours before and after the blanks were cut they warped over the next day. Which is why I always wait now.
+greenefly77 I have actually thought of the same thing. The bolt never gets in the way because it is the exact length of the hole, so if I had that done I would simple have them weld the connection of the bolt with the lid. It is a much smaller gap. I plan on eventually buying my own welder, which is probably when I will end up doing that.
Casey, you have helped me immensely. Great information and very succinct . I just purchased Alumilite products and "0" experience . I purchased a harbor freight 7x12 mini lathe for hopefully the best of two worlds. So, pressure pot with Alumilite. Thx. Will stay tuned , oh, I will be making pens and wife arts and crafts. Our retirement plan. Your great, thanks.
Diminishing returns from higher pressures. I've seen casting recommendations from 40-60psi. It's more a function of resin viscosity and mold material. Too little pressure with a viscous resin and complex mold and you may not compact the bubbles enough or fill the voids. Too much pressure and you may distort the mold. Which is also why molds should always be made from pressure-safe materials.
I know this is a 2 year old video but wanted to add my two cents all the same.
Pressure pots do not shrink bubbles. It actually increases the pressure which forces the air out of liquid inside it. Think of it as pressing in on all sides equally. It is like wringing out a sponge when squeezed. The molded resin needs to be inside and pressurized until the epoxy resin solidifies to keep air bubbles from reforming once pressure is reduced.
I do use the Harbor Freight modified pressure pot. If you spin/twist the slotted face plate on the pressure relief valve (not the stem you pull to release pressure) it will increase or decrease the pressure relief setting.
Now, the HF pots do tend to need resealing every fitting with teflon tape or liquid teflon seal. My tank will leak from the rim until it comes up to pressure. I have a mark on the lid over the leak prone area to remind me. So, if it leaks elsewhere I need to check it out. A good even slathering of Vaseline on the entire seal will help seal it. We used that same trick on pneumatic aircraft systems tubing joints and o-rings to seal out leaks. The pressure pot seal under the lid is just a large o-ring. One more thought, my seal was installed at factory upside down causing leakage no matter what I did to improve it. After I reversed it the pot sealed once it pressurized above 27psi. Now, we are talking about a HF product and my fixes may not be typical.
I do keep my air pressure line hooked up and under pressure while curing in case of leakage. It helps when your compressor is very quiet when running. Also, if I do hear my compressor running a lot I know I have a problem. I hope this helps someone else. Unfortunately, you will have to use your tank and test out how long to let your resin remain pressurized. It all comes down to volume of resin, temperature, resin cure/de-mold times, elevation, and barometric pressure to get an accurate pressurized time. I am not a scientist with a degree if physics and environmental science. I am a wood turner with a college experience that taught me one thing. Put it in the pot, pressurize it, uncork it 12-24 hours later and hope it did the job...
Thanks! I've watched a ton of these videos (planning on trying resin casting for the first time) and they all talk about the bubbles shrinking. It has never made sense to me. If it were true, the resin would become full of microscopic highly pressurised pockets of air, and it would explode prince rupert's drop style when the pressure in the pot got released.
Thank you Casey, the reason I asked is most people seem to leave over night and to be sure of maintaining the pressure that long I would need to leave my compressor on.
Thank you again, I am in the UK
Unless you have a workshop fitted with air lines all over your barn (my problem multiple air leaks), leaving the compressor hooked up would never be a problem, The compressor would cycle only 1 or 2 in 24 hours, if you had a real small leak.
TY for the video. Have you tried to reverse the center bolt and screw it in from the inside? If there is enough shoulder space, use a thick washer made of a softer metal (e.g. brass, copper or alum) that can conform to the shoulder surface when torquing the bolt down, but also have it doubled up with a hardened steel washer to avoid cracking the softer washer. A sealant made for engine head gaskets would be recommended as well. I'd only use Loctite on the surface area where the bolt and the nut are mating but not anywhere else. Loctite and similar products are designed to keep a bolt in place; they're not designed for sealing.
It couldn't hurt to use the same washer/sealant method on the outside either.
What if you are losing MORE than 1 psi? I have a leak at the joint under the gauge. I’ve taken it apart, wrapped the threads with Teflon tape, added a liquid thread sealer to the threads, and reinstalled but still leaking. Can you stop a slow leak without taking it apart again? Like maybe using hot glue or something similar?
It depends on if it loses enough to be lower than 45 psi or so after several hours. If you’re using alumilite and the leak is small enough that it stays above 45 psi for 3 hours, it’s fine.
You can’t really add something like that to seal it that easily. I’d just buy another gauge.
I'm having an issue with the pressure relief valve. It's supposed to open at 60 psi, but seems to be set at more like 45 psi. It continues to bleed pressure to about 45 psi. Is there a swap-out valve for this, or is it adjustable?
Adjustable. Just twist it
@@CaseyMartin707 Thanks - I'll have a closer look at it.
I used Zac's tip of putting lubricant on the rubber seal. Works great.
What model of air pump do you use for this pressure pot?? Thank you love your videos
Link is on the tools I use page in the video description! It’s a California air tools compressor
Hi, I have just bought the larger blue pot you have but haven’t used it yet, how long should I leave it pressurised for with the resin in it?
Thanks
Michael
Depends on the resin my friend, but I usually keep Alumilite in there for 2.5-3.5 hours with my ambient temperature here in California. Definitely do longer if it’s cold where you are or during winter. I would recommend cutting or turning only after 3-3.5 hours though
Hello. Does every casting need to be placed in a pressure pot or just items used with certain resins?
I watched many casting videos; but there is no clear answer.
I thank you for any help_ advice/ explanation you give.
jason wojnar the specific resin you buy will tell you whether or not it needs to be or if its even suitable to be cured under pressure
What kind of gasket material did you use when you plugged the hole left by the agitator on the TCP pot?
I have the blue pot and cured a small leak (at 60 lbs.) with Vaseline around the lid gasket. A tip from one of Zac's videos.
Vaseline is not done....you must use silicone grease....vaseline attacks the rubber lid !!!
@@MegaSkulltaker Perhaps but I wrote this 5 years ago and the gasket is still working fine.
Hello.
Can you lay the pressure pots on their side or it is recommended to keep them up right?
Thank you for yoir videos
I have seen multiple people do it. It’s mainly to accommodate longer molds. If you ever did have a pot malfunction though, it’d be much safer having the lid burst off up, rather than towards something.
However the best I saw was a large Binks pressure pot (type I’d feel safest doing it with), and the guy put a shelf or two inside of it, so he could fill multiple shelves with molds
Casey Martin .
Thank you for the reply and all the awesome videos.
How did you adjust or change the pressure relief valve on this pot mine goes off at 45psi? Thank you
Twist it. Right will tighten, lowering the safety PSI, left will loosen, and raise the safety PSI. Depending on your pot you might need a screw driver to twist it, or you might be able to with just your fingers or a wrench.
I have a hf pressure pot and modded it pretty well I'd say for my first time it held 50 psi for about 24 hour more than needed but I overtightened a T fitting and cracked and I had to reduce it now I can't get it to hold pressure for 4 hours it reduces to 30 idk what I did wrong someone help?
Did you strip the threads? If not then just get a new fitting. Since hardware stores are closed order one online. Maybe a local hardware store has a curbside pickup though
@@CaseyMartin707 huh didn't think about that one thank you so much!
Thank you so much for the information! It seems like my local Harbor Freight doesn't carry the pressure pots for some reason... It looks as if I'm going to have to buy mine online! Many blessings to you!
@AdamWayneone My local harbor freight store does not carry the paint pot. No free "ship to store" option if bought online. I contacted harbor freight customer service and they said they would consider adding free ship to store in the future.
One fix for the hole on top would be to take it to a local welding shop and have a round plate welded around it. No bolt needed and no inner bulk from the bolt and zero leaks.
I am thinking about getting the blue one how do you release the air pressure. I saw the other video and it looked like you put a plug in where the release valve is. I might have missed something. Thank you.
I release the air pressure with the valve that I use to put in the air! It goes both ways
Casey Martin thank you! Makes since
does the tank on the compressor matter as much as psi for pressure pots?
Could you use vacuum pots to stabilize the same as one would use pressure?
No, Alumilite cures too fast.
You have had good luck with your HF pot. Mine leaks no matter how tight I bolt it down.
I have two of them and it all has to do with replacing the factory seal on most of the bolts. Did you take out the safety valve? What I have done is basically unthreaded every single component that goes into the lid, and retreaded everything that’s necessary with new thread sealant, and plugged the ones that aren’t with new sealant too.
Mine leaks at the seal itself. No flaws in the seal, the flaw, I believe, is the pot's seating surface is uneven.
Can you use a pressure pot to stabilise wood ?
If you use it as a vacuum chamber, yes. Using pressure won’t work because as soon as the pressure is released the juice comes out of the wood it was being pressurized into. It’d only work if you could cure it under pressure
Thank you for the information, GREAT video's
Why use pressure pots and not let time dry it? Why us pressure pots?
Pressure pots don’t affect the time, they affect the clarity by removing bubbles. They make the resin cure crystal clear
If the resin cures in a few minutes, why leave it in the pressure pot for so long. Have you tried say an hour
+Chris Sammons The resin doesn’t cure in a few minutes, it takes about 36 hours for a full cure. The demold time accoridng to the manufacture is 90 minutes, but that is only with a 100g mass, and mine are typically 300g or so, which is why I wait about 4 hours.
I have waited about 2 hours before and after the blanks were cut they warped over the next day. Which is why I always wait now.
Take bolt off of lid , take lid to a shop and have them weld over the hole. No hole , no leak , no more bolt.
+greenefly77 I have actually thought of the same thing. The bolt never gets in the way because it is the exact length of the hole, so if I had that done I would simple have them weld the connection of the bolt with the lid. It is a much smaller gap. I plan on eventually buying my own welder, which is probably when I will end up doing that.
That’s exactly what I did. Got the blue pot from Grizzly, cheaper than the TCP
Harbor Freight sucks. Most of the lids are bent.
Book will not download
+jim reid Glad to hear it all worked out Jim!
What a waist of my time. Practice boy practice
.
Sorry you feel that way Gerald!