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help choosing a vacuum for a table press

Posted: Sat Jul 15, 2017 10:57 pm
by wdwyeriii
I built a table for the vacuum press and now my little vacuum does not have the power to suck out all the bubbles on the skis.

Does anyone know a spot in Europe where I can buy a vacuum that is strong enough to pull silicone on a large table vacuum press?

I live in Norway, so the closer the better. Thanks for the input!

Posted: Tue Jul 18, 2017 5:37 am
by backyardskier

Posted: Tue Jul 18, 2017 8:06 am
by Gilo

Posted: Wed Jul 19, 2017 11:36 am
by wdwyeriii
Thanks for the links. I will take a look at them. I am thinking that my vacuum does not get enough pull, as I keep getting bubbles and warping in my p-tex. I have a silicone blanket on a table press.

If there is one that you recommend, that would be great, but if not I will play around and give it a go.

Thanks for the links,

Posted: Thu Jul 20, 2017 7:34 am
by pmg
Hi, post some photos of your setup and your results, that will help us help you :)

Posted: Thu Jul 20, 2017 9:37 am
by burnside
Where is the silicone blanket in your set-up? Could the heat from that be causing the warp in your base?

pmg is right, pictures would help

Posted: Thu Jul 20, 2017 7:27 pm
by MontuckyMadman
The real questio. Is where is the thermocouple in relation to the heating blanket.

Posted: Fri Jul 21, 2017 1:26 am
by chrismp
Montucky is probably right. The bubbling could well be caused by overheating the materials in the press.

thanks for the help

Posted: Thu Jul 27, 2017 11:48 am
by wdwyeriii
Thanks for the help. I have a heating blanket that covers the whole ski placed on top of the silicone.

I have some photos, but I am on vacation now in the states. Your help would be most appreciated. I will post some photos here when I get back. I am thinking that either my frame is too small, or the vacuum not strong enough.

The problem looks a lot like waves in the ski p-tex and the veneer on top. I have had this issue a couple times, but thought the new press would help.

photos will come soon, thanks for your help

Posted: Tue Aug 08, 2017 12:24 pm
by 24Dave
I would try a stronger vacuum pump. I have had waves under a veneer layer before from a vacuum hose line that partially melted shut and also probably from not scraping the resin off the laminate fiber thoroughly enough in lay-up.

Photos of my issue

Posted: Sat Aug 12, 2017 1:42 am
by wdwyeriii
Thanks for your help here. Here are some of the photos of what I have been working with. I am still new to the process.

The first is the press; I put my heat blanket on top of the set up, but you can see that the vacuum is not pulling the silicone all the way down.

The second and third photo are the bubbles that have occurred in the veneer and the layup.

I am posting some links to photos on here, I was trying to figure out how to get them on the message, but it is my first time posting a photo on here, so let me know if you don't see them.

Again, any help would be great.






Posted: Sun Aug 13, 2017 8:21 am
by chrismp
Is your hole press MDF? If so, that is probably a big part of your problem. Untreated MDF is really porous and lets a lot of air pass through. You need to seal the MDF or build the press out of a material that's airtight.

Posted: Sun Aug 13, 2017 9:42 pm
by wdwyeriii
Just the frame is untreated MDF. The table I covered with Epoxy to seal already, but you are right that I should seal the frame as well. I will coat the MDF frame with epoxy and see if that gives me a bit more power.

Posted: Tue Aug 15, 2017 12:03 pm
by burnside
In addition to sealing the frame, you could try pre-forming the silicone by hitting it with a heat gun at the tips and stretching it by hand. I think Sammer did something along these lines with his vacuum press

Posted: Tue Aug 15, 2017 11:46 pm
by chrismp
I think sammer has a PU vacuum membrane, not silicone. Silicone should be stretchy enough as is to conform to the mold.