Maybe we have our terminology mixed. To me that is a standard ring seal. Dewar seal for me is cutting the jacket to length and having the insert stick out a bit and then flared to the jacket. Then sealing the flange onto the Dewar. No waste of material and overall tolerance can be hit within a few mm.
Love your videos, thank you! What is the setup on your cross fires? It seems like you ha e them on some kind of pedal? Im about to set up an old litton 8 burner 7 jet and i want to make it work for me the best i can.
Pretty darned fascinating... wow. I have a condenser that has a pinhole in the water jacket... is this something I should be able to fix myself by re-flowing just that spot with a torch? Might I crack it if I don't heat everything around it first? I have not special tools... just a propane torch, which might not get hot enough anyway. Thank you!
noooooooo... you cannot use a propane torch to fix it.. ther is a process , you must first preheat the glass evenly over a period of time depending on wall thickness, then you will need a slightly hoter torch, mapp gass would do, then you need to hold a specifick temperature for an hour, and then ramp cool slowly over time depending on wall thickness
Ryder Spearmann You wouldn't need to heat the whole thing. You could spot heat it very slowly and allow the radiant heat to bring the surrounding glass to an even working temperature before you melt the hole away. Then cool it down as slowly as you heated it. Depending on the thickness and type of glass you might have to heat even slower. If it was a "worked" hole it could be easy but if its a crack it will be nearly impossible without a kiln. But also you might not want to seal it -> when you heat a sealed enclosure the contents (esp. air or water) will cause a pressure change and your glass vessel could explode in use.
Yeah, I was going to have a certain amount of waste on each end of the jacket (colums were over a meter long)which was not worth saving afterward. So, I just made my center tube the right length (slightly longer to account for making the dewar and thickening it up), centered with wale 2" heavy green tape. I grabbed the extra 120mm with the flange. I pull the jacket down very thin, then just kissed the center tube.
I just went over 20 last Aug. !0 years in production and 10+ at the university. I am so glad to be out of production work..a lot of one or two of that and a lot of r and d.
How do you keep the inner tube supported? I've tried wale tape and I find it very hard to remove after I make the seal, corrugated paper burns up on me. It looks like you only have a small amount of wrap around it too, yet it seems to stay very centered. Any help would be greatly appreciated!
+gpayton7890 I made up some of the 2" wale tape (about 50" or so, folded length wise), about 8" long, . When I put them in, I used a strip of paper towel between the Id of the big tube and the od of the inner tube. To minimizing rubbing/scuffing the glass.
Amazing! Where are you at? I know someone makes these in Cleveland. Also, is this one made for some atmospheric scientist? Because I had one made like this before.
Typically I would flare up the inside tube up to the outside and complete the dewar seal, and then attach the flange. in this case I had to use the full length of the inner tube and had no room for mistakes, and I was required to keep the inner tube within tolerances of length. This is just a different technique for doing a dewar seal from the wheeler glassblowing book.
Your videos are hugely educational, thanks for every single one of them.
Oh yeah that time when UA-cam fixed motion blur
Maybe we have our terminology mixed. To me that is a standard ring seal. Dewar seal for me is cutting the jacket to length and having the insert stick out a bit and then flared to the jacket. Then sealing the flange onto the Dewar. No waste of material and overall tolerance can be hit within a few mm.
Love your videos, thank you! What is the setup on your cross fires? It seems like you ha e them on some kind of pedal? Im about to set up an old litton 8 burner 7 jet and i want to make it work for me the best i can.
Pretty darned fascinating... wow.
I have a condenser that has a pinhole in the water jacket... is this something I should be able to fix myself by re-flowing just that spot with a torch? Might I crack it if I don't heat everything around it first?
I have not special tools... just a propane torch, which might not get hot enough anyway.
Thank you!
noooooooo... you cannot use a propane torch to fix it.. ther is a process , you must first preheat the glass evenly over a period of time depending on wall thickness, then you will need a slightly hoter torch, mapp gass would do, then you need to hold a specifick temperature for an hour, and then ramp cool slowly over time depending on wall thickness
Ryder Spearmann You wouldn't need to heat the whole thing. You could spot heat it very slowly and allow the radiant heat to bring the surrounding glass to an even working temperature before you melt the hole away. Then cool it down as slowly as you heated it. Depending on the thickness and type of glass you might have to heat even slower. If it was a "worked" hole it could be easy but if its a crack it will be nearly impossible without a kiln. But also you might not want to seal it -> when you heat a sealed enclosure the contents (esp. air or water) will cause a pressure change and your glass vessel could explode in use.
Why not use a Dewar seal? Are you using hydrogen in your cross fire? Looks great!
Mike, I did do a dewar seal before I attached the large flange. Yes, I am using Hydrogen. thanks
I understand...production is very beneficial for the beginner but for the advanced it can drive one crazy.
Yeah, I was going to have a certain amount of waste on each end of the jacket (colums were over a meter long)which was not worth saving afterward. So, I just made my center tube the right length (slightly longer to account for making the dewar and thickening it up), centered with wale 2" heavy green tape. I grabbed the extra 120mm with the flange. I pull the jacket down very thin, then just kissed the center tube.
Maybe I am going to try doing some small electrochemical cell.
Never done it before. Is there some respiratory protection that you recommend?
At this point, I would classify it as a dewar seal (we just used different ways to get to this point). How long you been doing it?
I just went over 20 last Aug. !0 years in production and 10+ at the university. I am so glad to be out of production work..a lot of one or two of that and a lot of r and d.
Where can I buy this turning machines for Brazil?
How do you keep the inner tube supported? I've tried wale tape and I find it very hard to remove after I make the seal, corrugated paper burns up on me. It looks like you only have a small amount of wrap around it too, yet it seems to stay very centered. Any help would be greatly appreciated!
+gpayton7890 I made up some of the 2" wale tape (about 50" or so, folded length wise), about 8" long, . When I put them in, I used a strip of paper towel between the Id of the big tube and the od of the inner tube. To minimizing rubbing/scuffing the glass.
Amazing! Where are you at? I know someone makes these in Cleveland. Also, is this one made for some atmospheric scientist? Because I had one made like this before.
I've been in the glass industry for 18 yrs. My first 5 was a neon Glassblower and I've been in scientific for 13....how about you?
???? is it my imagination or was the first part of this video a vary large non necessary step..!!???? there was no point to that
Typically I would flare up the inside tube up to the outside and complete the dewar seal, and then attach the flange. in this case I had to use the full length of the inner tube and had no room for mistakes, and I was required to keep the inner tube within tolerances of length. This is just a different technique for doing a dewar seal from the wheeler glassblowing book.