infusing a plug/mould?

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#1

had a thought the other day whilst making a mould (didnt turn out to good)

Is there any reason why you cant put your gelcoat on the plug then lay up the fibreglass dry (maybe a layer of woven first to give more chance of getting a nice uniform surface) the infusing the resin?

Any thoughts?

Also there was a post on the other site ages ago which has been deleted :roll: about using mircoshpere’s (i think) mixed with resin to put in corners to smooth them out when making a mould so the fibreglass didnt bridge.
Has anyone saved the webpage or made it available off line? If so can you post it on here or can someone confirm its microspheres not bubbles to use ( or the correct things to use)

#2

people have made shortcuts for years using a multitude of fillers to make the layup easier. i would be careful how many shortcuts you take. Weigh the consequences versus the longevity of the tool.
I would be certain to put a few layers of glass into the corners, and then too, i would not just mix microspheres into the resin, i would cut up some glass fiber and add that carfully to give it some strength. this makes laying multiple layers much easier, but it takes away from possible longevity of the tool.

#3

cheers doogie i would/will not try to use the fillers that much but on this plug (gearstick surround) but it has two near right angle steps in it all the way round.
I must have spent nearly 25 minutes on it and thought id only have a few little air bubbles at the most. Left it to cure came back and… its scrap basically.
I tried the thing of using two strips and building it up to no aval. Maybe try a different wieght/thickness csm next time.

Any thoughts on the infusion to make a mould the only problems i can possibly see is if the plug has a raised bit in the middle like my gear stick surround the vacuum would probably pop/squash the card filling the hole but for a solid plug i cant see any reason why not. Even if you could only infuse a few layers of fibreglass the mould should be air tight and you could always build it up afterwards

#4

my mold construction as of now

-surface coat
-cotton flok before cure of surface coat
-layer of caposil mixed like vaseline
-4 oz cloth pushed into the caposil and all caposil squeegeed out so the cloth is touching the surface coat directly. I also put the cotton down so there is an added physical bond to the chemical bond.
-after the cloth i fill in any stupid corners with a caposil/mat mix in a unidirectional strand kind of way to fill in the corners. i’ve found that instead of using just caposil or resin as a corner filler that the need in my production mandates that i make absolutely sure that nothing is going to break when being handled by monkeys who not only throw there shit when they get mad, but also my molds. MF’ers.
-layup 1.5oz mat torn in half in thickness so that it’s a .75 oz effectively and layup anywhere between 8 and 12 layers depending on thicknesses weak areas and such.
-top off with paper towels which are just there to keep the splinter ration down from the mat. we used to use cloth but… why? it’s not there for support.

take what you want out of this and use it well my son…

oh, and as far as infusing a mold, if you figure that one out, let me know, i’m ALWAYS looking for shortcuts that work.

#5

I have infused three molds so far. You have to be careful what you pick and choose for infusing.
The first question is can I pull a vacuum on it.
2nd question is how do I pull a vcuum on it without collapsing it.
Third is if I can pull a vcuum on it wihtout collapsing it, will there be a possiblity of it leaking.
If you can meet that criteria and answer it so you kow what your up against, you can infuse a tool. I did it with a set of mirror caps, a cnc cut model that wouldn’t collapse, so I bagged it to the table. and the last one I did it with was a tool that I was going to use as a dupe from an existing tool to make more tools. I will be infusing several tools from that tool today!