vacuum press

[zach mahlum]

First off, I am new to the forum.

secondly, i would like to know all the major parts of a vacuum press. i would like to make my own snowboards but i am limited on money because i am only 15. where can you get all the necessary things to build a vacuum press? i know this has been a hot topic in this forum but i could not find all the information in one place.

[RoboGeek]

welcome to the forums!

The biggest problem will probably be obtaining a good vacuum pump. You can buy bags or create your own. You'll need breather material and really thats about it. You don't need a top mold so its a pretty basic setup to use

[hafte]

Check this thread. There was a bit of input by several of us. http://www.skibuilders.com/phpBB2/viewtopic.php?t=830

I also know of a guy in New Zealand that used an old vacuum cleaner to make surfboards. The only problem was he had to run the thing until the cure was done. Don’t use your mom’s. It will kill it over time. Here is a thread on a surfboard builders site that discusses the tech. And the use of the below materials. I apologies for the repost of this site but I have found the info very useful.
http://www.swaylocks.com/forum/gforum.c ... 946#183391

You will also need:
bagging film 6 mil plastic at home depot. I didn’t have much luck with this, YMMV
Release ply Same as the bag material
Sealant tape masking tape can be used
Breather ply paper towels, cardboard, garden shade cloth.
Peel ply

All of this stuff can be found here for a reasonable price. And they are fast.
http://www.fiberglasssupply.com/Product ... gging.html

The only products I buy from these guys is the bagging film, peel ply, release ply and the two sided tape. I end up cutting the bagging film into the sizes I need and tape that directly to the ski form/tool.

My layup goes like this.

Put the sealant tape around the perimeter of the form/tool with the wax paper left on.
Release ply on the form big enough to wrap the skis.
The ski/snowboard layup
Peel ply
Breather ply several layers that reach to the outlet for the vacuum. Put the outlet in a place where the excess epoxy will not clog it up.
Release ply wrapped over/around all
Lay the bag film on top. Make it big enough to leave a pleat down the middle. My form is ~13” wide and I cut the film 16” wide.
Slowly remove the backing for the tape sticking the bag film down as you work your way down each side. Do the ends last and don’t pull the film tight across the form or it will not conform to the shape of the ski/snowboard well.

When my partner in this comes back from Thailand I’ll see if the pictures are still on his camera and I’ll post some of those in a journal.

Hafte

[zach mahlum]

that must have been a big vacuum cleaner to mold a surfboard. i have a couple of shopvacs that we picked up throughout the years. do you think i could use one of those. no one else in my family has used it in years and if works perfectly.

[hafte]

Well if you go to the article Bert talks about burning out his wife’s floor vacuum and running through several other second hand models before he bought a vacuum pump. It really doesn’t take much. A vacuum cleaner will pull more than you think. The hard part is getting the connection sealed tight.

A shop vac would work fine. Get some plastic and some tape and run some tests. Put some thing in a bag and see what you can get away with. The bad part of the vacuum cleaner is that it will be difficult to hear/find leaks while it is running. If you can come up with a way to stick a valve in the vacuum line you could close the valve and turn off the vacuum to see how you are doing for leaks.

Hafte

[G-man]

I have a very nice venturi vacuum system that I use for vacuum clamping of small and medium sized parts. But, on the larger parts (like profiling cores), I have gone back to using my 25 year old shop vac. It sucks 50 times the vacuum as my venturi system and I don't have to worry if I have a few leaks. I've even created some adjustable vacuum leak devices so that I can create some controlled leakage in order to keep from working 'old faithful' too hard.

So, regarding using a shop vac for vacuum bagging a ski or snowboard, I think the vac could pull enough vacuum to get the job done with the added benefit of being more forgiving of a few leaks. However, I'm afraid that the extended time demand on the vac could easily give the poor old thing a coronary. Pulling on a completely closed bag for a few hours would be really hard on a shop vac... it seems... never done it so I don't know for sure. It only takes a few minutes to profile a core, but it seems that I almost always hear a sigh of relief coming from my vac when I disconnect it from the profiler and allow it to breath more freely.

G-man

[Idris]

I use a refrigirator pump as a vaccum pump. 4 pairs of skis and a snowboard later + 4 goes to laminate ski/board cores. It's still going strong. I do have a cutout switch that stops the pump running at about -12 psi. (Do a google search to get plans for one of these). I use proper vacuum bags but have used folded plastic sheet and tape. I also use a regular vacuum cleaner to pull the initial vacuum because as others have said it's much faster. Being carefull about the leaks is the important thing for a good vaccum. no sharp edges is a good place to start, folloewd by a clean surface under your bag.

Running a vacuum cleaner for more than 30min with the end blocked will kill it or at least cause it to shut down due to overheat. Mine lasts about 15 min now. I has my cutout switch fail on the fridge pump. The thing ran for 12 hours straight. Sure it got hot, but didn't fail.

[kirol]

I just got a 70's model refrigerator compressor that a guy converted into a vaccuum, once i finish my mold and do a few other things i can attempt to create some skis

[M.F]

Is there any websites where they tell you step by step how to make a vacuum pump out of a refridgerator compressor?
Or do can you guys tell show me pictures of your own vacuum pumps?

Is it possible to make high enough vacuum out of a air compressor? and how?

[Idris]

Here is mine.



Some other ones I found in a 5 min search

http://users.pandora.be/Toothless/Tooth ... acuum.html

http://www.hackaday.com/2006/09/10/refr ... m-bagging/

[M.F]

I see you are using a syringe, but is it made of plastic og glass?
I read on one website that it would be better with a glass syringe than a plastic syringe...

is it necessary to use breather over the skis?

[Idris]

Plastic syringe - I had no acess to glass ones, plastic works fine for me - its a giant one for feeding calfs

Breather - yes, I use carboard, it's free

[zach mahlum]

First of all, thanks for all the feedback. Second, would this bee a good setup for pressing skis?

http://www.instructables.com/id/SE7LPPMF3HY3RUR/