It’s all good man
Interesting thread. When pressing maple veneers over top of a one sided mold it is better to have a thicker vacuum bag than the materials used tor vacuuming composites like fiberglass and carbon fiber. My Roarockit kit was made specifically for pressing wood veneer and it does this very well.
Pressing flexible carbon cloth the material is usually draped over as pre-existing shaped 3D form which requires little or no pressing power. In such you can get away with pulling much less of a vacuum. Around 7 pounds per square inch will do the job. This is what a fan driven home vacuum cleaner will pull. The trick in using a vacuum cleaner is making sure you have a bag that can be completely sealed and isolated from the vacuum source so that you can remove the vacuum cleaner once you have pulled a vacuum.
Vacuum cleaners need to have air flowing over the motor to cool them. If you leave the vacuum connected to the bag the motor will heat and eventually burn out.
I have made at least 20 carbon boards with great results using our kit. These all have been with maple veneer cores. It is important to know that the hand pump in our kit produces around 13.5 to 14 pounds per square inch of vacuum. This is more than enough for pressing skateboards or furniture components.
Anytime I have done a pressing with a foam core I make sure I do not pull a full vacuum with our kit. If you are doing carbon cloth work with a foam core 13.5 pounds of pressure can crush and distort the foam core. Most surfboard or windsurf board makers only use 7 pounds of vacuum for this reason. Any more and the vacuum will ruin your project. With my projects, since I was putting carbon onto veneer I could use as much pressure as I wanted. This is an important distinction between foam core and solid core pressings that will make or break a project. The vacuum cleaner method will work but unfortunately not work well for pressing veneers over complex one sided molds…
Carbon work is usually done for two reasons. Strength and object lightness. Impregnating carbon without a vacuum bag will give you strength but not necessarily lightness. Too much epoxy = weight. A vacuum bag setup with peel ply and breather mesh where the excess epoxy is wicked away out of the carbon as it sets will produce strength and lightness. This can get expensive as you need a vacuum bag. carbon cloth. peel ply, breather mesh and epoxy to do the job properly.
I hope this is informative and helps to decipher a couple of methods of using vacuum bags. Ted at Roarockit
3 Likes
Just made this one without vac. I used a paint brush to apply the resin, tomorrow, i will pop it out of the mold, giving it extra time to dry. After 3 hrs, it is very solid so far, hope it comes out good, 1st time making one out of fiberglass.
.
3 Likes
nice man, yea its pretty easy, just tedious and gotta keep checking to make sure nothing lifts up while it dries
1 Like
It is quite easy if done right. Mine got out ok, but to make things easier you should use fiberglass cloth not fiberglass mat. I used fiberglass mat and that is hard to get nice results. It does work, but it leaves you with a little disappointment.
yea cloth conforms a lot easier than the mat does
1 Like
let the fidgeting begin.
1st layer is mat and the rest layers are cloth.
1 Like