Slow infusion problem

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#1

What are you guys using for a vacuum hose set up from the resin/vacuum pot to the mold? I bought some 1/4" i.d. wrapped vinyl hose ( thick clear hose wrapped with white nylon found at Lowes and HomeDepot). To that i added some fittings on each end and air compressor quick disconnect fittings join the hose from the vacuum pump to the pressure pot. I haven’t registered any vacuum leaks with that hose set up, even turned the pump off and let it all sit for 10 minutes… it dropped to 27hg.

For the life of me i can’t get the resin to get vacuumed up thru the resin line from the resin cup. The hose is fully immersed in resin and i did release the clamp from the line. I get one or two tiny air leaks in the bag, but i’ve gotten those type of leaks BEFORE i had the resin pot in use and man…it sucked the resin out of the cup fast back then. Now it’s like an old lady sipping a soda thru a straw, takes for ever.

Any ideas? So really the only thing new to my set up is the vacuum resin pot and that quick disconnect line. Everything worked like a champ before i changed/added those two things. And the bag isn’t pulling down tight against the mold like it should… i mean it should be pressed down damn hard against the mold, and i can slightly lift the bag like 1/8 to 3/16" off the mold surface with the vacuum pump running.

#2

I’m assuming that you are using the 300/21 resin, I’m not sure why this is happeneing I have used this resin with tubing thinner than that. I would have to say that perhaps the tubing itself is not air tight… hence pressure is always equalizing within the tube?!..

Try applying a positive pressure to the tube and sealing the one end and seeing what happens, maybe put it under water to see if there are any bubbles escaping…

#3

I just realized what you are saying in your last paragraph, remove the quick disconnect and see if that helps, if it does we have found the problem, if not work your way backwards unding things one at a time.

#4

I dont know if this is it, but the feedline hose will have such a good suction that it will keep wanting to stick to the side of the cup, I have had that happen before, but quickly fixed it. cut the feedline so it has a notch in it so it cant create a seal on the side of the cup

#5

The quick release fittings are for vacuum use or air pressure?:confused:

#6

The quick disconnect fittings are for air pressure. But when tested that hose and fittings held 27hg for 10 minutes without dropping. It did make an initial drop from 29hg over that same 10 minute time.

#7

Odd.
I’d get away from the QC’s anyway. Might seem like there is no leak (which you pointed out there is anyway), but it also might be only showing in one area.
Also, check your resin line end. cut it at an angle, so it doesn’t suck up to the cup, blocking the inflow, as hojo said. Very common mistake there.

#8

Vac. QC are dbl. seal units (also seals when disconnected too) and can be had at MacMaster Carr.