i want to know if it's possible to put a clear top sheet with a vacuum press .
If some one did it please explain me who do to for to remove the bubbles under the top sheet because the maximum pressure with vacuum is about a depression of 1kg by cm² and i think it isn't very big than you big press !!
I have done both clear and no topsheet with a vacuum press.
To avoid visible bubbles makes sure you 'wet out' the glass thouroughly. This means - at least in my case. Using a paint brush to push the resin into the glass. Doing this somwhere warm also helps (20-30C).
You need to put somethig smooth over the top layer of glass before your breather fabric/cardboard. To avoid the breather fabric leaving an imprint. I used a thin layer of plastic and a scrap topsheet. Others have used a thin layer of plastic and then masonite. The masonite might work well enough as a breather itself.
I made the mistake of just having plastic then cardboard once. This left an imprint from the carboards corrugations in the top of my skis. Took me hours to remove with a belt sander.
Idris wrote:You need to put somethig smooth over the top layer of glass before your breather fabric/cardboard. To avoid the breather fabric leaving an imprint. I used a thin layer of plastic and a scrap topsheet. Others have used a thin layer of plastic and then masonite. The masonite might work well enough as a breather itself.
I made the mistake of just having plastic then cardboard once. This left an imprint from the carboards corrugations in the top of my skis. Took me hours to remove with a belt sander.
I also made the mistake of jsut having plastic and cardboard. It left imprints.
Now I just use a layer of plastic, then a sheet of 1/8" masonite. Everything comes out nice and smooth, and the masonite acts as the breather.
Hi everyone!!!
By rules of forum SB it`s necessary to write even one message. And that this message was not empty I want to ask a question:
- At pressing a ski under topsheet there can be air (bubbles)... Whether it is necessary to make mixed press? Whether a ski to place in vacuum film and to put under pneumatic press. it`s necessary to make it or any of these presses at the correct approach can give out identical result? All depends as i understand from pressure?
I the beginner in build a ski also saw at familiar a ski which he have made for the first time. He had problem with bubbles. It would not be desirable to repeat this mistake.
Many meet such problem?
Thanks
Misha
build some kind of roller you can "burp" the topsheet with, once you get everything laid up and all the layers taped down etc, roll the heavy ass roller from center to tips and that will help with some bubbles/creases.
you can build one out of large diameter pvc or similar, or a large dia steel pipe is prolly heavy enough on its own.
my plan is to have a clear topsheet with a printed graphic below. so the question, double-ply (fabric printed on and covered with something clear...) or something clear were the graphic is already printed on, like pvc, nylon, pe.... i don t know which materials bond best and are printable??! any experiences?? ...and... it will be vacuumed, cap-construction with a 45° bevel on the wooden sidewall, so it must not be too thick to enclose easily around the core...
