I’m using 3/8 polyethelene hose for vacuum bagging. How do you guys secure the vac hose to the bag with zero leaks? Suction cups? plastic line T’s?
the parts i’m doing are relatively small so i think i need just one vacuum line. The surface area of the mold is less than 2 sq ft.
Vacuum bagging sticky tape…
Good info! What type of clear vac line are you using perfeng? Mine is polyethelene ridgid plastic tubing.
ohhh awwww yeahhhh, flow medium… I need to order some of that. I don’t know how i missed ordering it with my 4 past shipments. duhh moment.
Fastrr
I do the same as perfeng but i put a double row of tape at the vac line and resin inlet.Only an inch or so either side.
Baz
i thought i had ordered a roll of yellow bagging tape, guess i forgot to. I’ll have to get that and the flow medium together on my next order.
I double tape also. Just not in that picture. =)
That is standard vinyl tubing. The PE tubing is too ridiculously stiff for me to work with. I have no problems with the vinyl as long as it is smaller than 3/8" OD. Anything larger will crush.
Thanks guys. I will try and do the sticky bag tape to seal the line to the side of the bag.
I do have another question. I know there are probably many ways to make a manifold that has a vacuum valve with lever, and vac gauge on the manifold… i would like to do something like this possibly.
I was looking for a hose that can be used to run off the pump to the manifold, then from there to the resin vacuum pot. Anyone have pictures of how their vacuum set up looks? Particularly if you are using an electric vacuum pump set up.
My vacuum gauge came in today…woo hoo 
I also ordered the flow medium and other infusion stuff i needed. So far all i have for vac plumbing is some 3/8 polyethelene hose. I’d like to finish the plumbing this week or next. I should be ready to infuse in a couple weeks or less.
I don’t have a vacuum pot so I made a resin trap out of PVC pipe (white one). I can pull 2 or 3 vacuum lines (or more if I like) from it. All I do is put a length of hose on each outlet. Small vice grips or cable ties crimp the unused lines. The vacuum guage is on the pump. Hard to see in the pic but it’s just behind the valve. The vacuum line runs to a reservoir (black pipe) then to the trap.
Knotty, can you take a close up pic of where your vacuum line enters the vacuum pump? What fitting did you need to buy and where were you able to buy it from? Thanks
I think there’s another thread on here about threads on Robinair pumps! (pardon the pun). Hold on I’ll go look…
My contribution to that thread starts at post #4.
http://compositeforum.werksberg.com/showthread.php?t=2281
I’ll go get a pic. BRB
I know I pooched the tapered fitting that came on the Robinair by jamming the NPT fitting on it. I tried to locate the correct fitting but gave up. Just gooped the threads real good and cranked it down. I’ve done a leak down test on the whole setup and it’ll hold vacuum for a week no problemo. I have heard that some larger volume pumps can suffer damage when they start up under high vacuum loads. I’m going to plumb in a vac reservoir in front of the valve so I can start it w/o any vacuum on the pump.
From JoeWoodWorker dot com
“The sub-reservoir is a small holding tank of free air that allows the pump to achieve full RPM when starting up without back-pressure against the pump intake port.”
Hope that helps.