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Nice job, John as always. You have a couple shots of the final product? I may have to break down and finally get a vacuum bag setup.
Doug
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(01-26-2023, 09:30 PM)Tapper Wrote: Nice job, John as always. You have a couple shots of the final product? I may have to break down and finally get a vacuum bag setup.
Doug
Not of these panels yet, but here's one of some 8 mm walnut plywood I made for the wall clock I made last year. Again, 5 plies, all walnut in this case.
If you look closely, you can see the plies on some of the parts in this photo:
The vacuum bag is home made. I used 30 mil vinyl and glued the seams with PVC pipe cement. You can make any size you need and for a lot less money than buying a bag. That bag is now almost 30 years old and I've made hundreds of pressings with it. I made another bag more recently and used 20 mil vinyl for increased flexibility. Polyurethane has the best flexibility but the price of commercial bags is more than I care to spend.
You don't need to spend a lot on a vacuum pump or pump control system either, though some do. I use a Gast vacuum pump with about a 2 cfm capacity that I got used for less than $100. The "control" system is nothing more than an on/off timer that cycles the pump often enough to maintain the vacuum above about (really less than) 18" Hg. If you use Titebond type glue you don't need any control system. The pumps are made for continuous duty, and you only leave it in the bag for a couple of hours until the glue sets. With Unibond 800 or epoxy which take longer to set, however, I use it to reduce the wear on the pump.
A vacuum bag system opens up a host of new opportunities, from easily making bent laminations, to veneering, whether using commercial veneer or shop sawn.
John
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(01-27-2023, 10:43 AM)jteneyck Wrote: The vacuum bag is home made. I used 30 mil vinyl and glued the seams with PVC pipe cement.
Where did you source the vinyl?
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01-27-2023, 01:05 PM
(This post was last modified: 01-27-2023, 01:12 PM by jteneyck.)
(01-27-2023, 11:27 AM)mound Wrote: Where did you source the vinyl?
The first time from McMaster Carr. The second time from my local boat canvas maker, who was substantially cheaper. If you decide to make a bag, regular PVC pipe cement works as well as the special stuff sold by Joe Woodworker. Do not use the cleaner first. Just wipe the seam with DNA to clean it, let it dry, and then smear on the cement with the dauber. I don't know why it doesn't work as well with the cleaner first, but that's what I found.
John
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Bonus photos Doug. Here are the cherry/ash plywood panels. 3/8 and 1/2" with 5 layers:
3 mm and 1/4" with 3 layers:
John
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Very nice John! Thanks for the info on the vacuum bag. I can't promise I won't call you when/if I get around to making one!
Doug
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(01-27-2023, 10:43 AM)jteneyck Wrote: Not of these panels yet, but here's one of some 8 mm walnut plywood I made for the wall clock I made last year. Again, 5 plies, all walnut in this case.
If you look closely, you can see the plies on some of the parts in this photo:
The vacuum bag is home made. I used 30 mil vinyl and glued the seams with PVC pipe cement. You can make any size you need and for a lot less money than buying a bag. That bag is now almost 30 years old and I've made hundreds of pressings with it. I made another bag more recently and used 20 mil vinyl for increased flexibility. Polyurethane has the best flexibility but the price of commercial bags is more than I care to spend.
You don't need to spend a lot on a vacuum pump or pump control system either, though some do. I use a Gast vacuum pump with about a 2 cfm capacity that I got used for less than $100. The "control" system is nothing more than an on/off timer that cycles the pump often enough to maintain the vacuum above about (really less than) 18" Hg. If you use Titebond type glue you don't need any control system. The pumps are made for continuous duty, and you only leave it in the bag for a couple of hours until the glue sets. With Unibond 800 or epoxy which take longer to set, however, I use it to reduce the wear on the pump.
A vacuum bag system opens up a host of new opportunities, from easily making bent laminations, to veneering, whether using commercial veneer or shop sawn.
John
Nice job. The clock is SWEET!
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(01-30-2023, 08:38 PM)iublue Wrote: Nice job. The clock is SWEET!
Thanks. I call it the clock from Hell. I built the Deco clock from Clayton Boyer, which runs and runs and runs w/o issue, and also bought his book on clock design, because of all the trouble this clock gave me. I never could get it to run for more than a day or two and usually a lot less than that. I found and tried to fix many problems but eventually gave up. Boyer's design book made it clear what not to do, and several of the things he mentioned are exactly what the other clock designer had done.
I redesigned the clock and am in the process of cutting and assembling the parts. We'll see if it runs as well as the Deco clock. I really like the looks and cadence of this clock so I hope I'm successful. Stay tuned.
John
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