vacuum and layup questions....

For discussions related to designing and making ski/snowboard-building equipment, such as presses, core profilers, edge benders, etc.

Moderators: Head Monkey, kelvin, bigKam, skidesmond, chrismp

Post Reply
skimakermark
Posts: 6
Joined: Fri Jan 01, 2010 2:24 pm

vacuum and layup questions....

Post by skimakermark »

Hi everybody.

I've gotten stacks opf help and info from reading through the various posts on this forum and from the site in general.

some questions on vacuum bagging. I have all the bits and pieces to start the layup, except the vacuum pump. What should I buy? I know its a bit of a muppet question, but I've seen fridge vacuums one ebay, but don;t want to buy them if they won't work well. Is it worth spending $500 on a good commercial one that will definatelyt do the job (and if so which brands or models should i look at?) or get a cheap fridge one on ebay? How do I hook it all up to my vacuum bag? Hoses, seals etc...btw, I'm in Australia, so sourcing stuff is hard...

Also, I have just milled up and vertically laminated a whole bunch of paulonia, and wanted to make sure my lay up plans were in order. Can anyone correct me if any of this sounds wrong or a bad idea:

pre possished aluminium casette. On top, p tex, cut to shape, with edges super glued on. a strip of carbon down the centre, wetted out with epoxy, then 22oz glass, wetted out again. Wood core. More epoxy and wetted out glass, thin wood veneer and a final layer of epoxy to seal it all. perforated plastic, bleader sheet (is cardboard ok? anything in particular?). in the vacuum bag, seal it up, hit the 'vacuum' button, put it all in some sort of heat box at 70 celcius. next morning, take it out, let it cool, open bag, cut flash off, grind base, tune edges, mabe sand and re varnish top, attach bindings, go skiing.

is that pretty much it? is carbon a good idea? paulonia is pretty bendy...

wow, long post. any answers would be AWESOME. thanks guys.

mark
skidesmond
Posts: 2338
Joined: Tue Apr 07, 2009 3:26 pm
Location: Western Mass, USA
Contact:

Post by skidesmond »

I don't use a vacuum press so I can't help out there.

I use VDS rubber strips over the metal edges before laying down any fiber glass. I think many others do it also. I can't say it's wrong/bad not to use VDS. I'm new to ski building too and since most of the others use it, I do too. It's cheap and for sale at www.skibuilders.com.

It's supposed to help prevent delam and shearing between the metal and fiber glass. Also supposed to provide a dampening effect to reduce chatter. Good luck.
twizzstyle
Posts: 2207
Joined: Tue Mar 07, 2006 8:25 pm
Location: Kenmore, Wa USA

Post by twizzstyle »

You might also consider putting the same layer of carbon fiber on the top. If you don't and you do a heated cure, you may get camber changes when it cools.
CAFactory
Posts: 31
Joined: Fri Oct 30, 2009 1:37 pm

Post by CAFactory »

viewtopic.php?t=907

If using cardboard for a breather, you will want to use a thicker solid plastic (around thickness of base material) before the cardboard. I wouldn't put anything with holes in it directly above the topsheet, because imprints may be left.

The best case scenario would be just to buy breather fabric and peel ply.

Otherwise everything looks good to me.
----------------------------------------------------
So something like this:

Outside Bag

Cardboard

Plastic around the same thickness of base material

Peel Ply if needed (if above plastic will bond to epoxy)

Topsheet

The rest
Post Reply