Unlimited jd

iTrader: (5)

I have some one off stuff we're doing for my fountain project. Seems like a lot of work to make a plug, then a mold and then layup a part. I've never done any mold work, for a one off part why not just make the part out of the core material and layup over it then finish it? Seems like you'd have to do that for the plug anyway right? I'm sure I don't fully understand the exact process or reasons why so that's why I am asking

502ss

iTrader: (3)

Watcha making?

dereknkathy

i guess you have to fab the part first to the shape-size you want it. so you must use stuff you can work-shape till you have the piece. plywood, plexi, cardboard, coffee can lids...unless you can eyeball it a little smaller so the glass you pull off it is the correct finished size, you really have little choice but to make one that is too big and use it for the mold. either that or use the plywood, plexi...as finished product.

Unlimited jd

iTrader: (5)

Console, dash, and windshield. Seems like twice the work to do the plug, mold and then the part, when I can cut the core material to shape glass it in and then finish it. I can see obviously doing it for parts that don't have or need core.

dereknkathy

the plus side of the mold is you post build pics and everybody sez "where can i get that setup?" because a mold is really only 1 or 2 layups of the part, not the whole thing. worst part is sweating whether the glass will release from the mold twice...once when making the mold and again for the finished part. and then there is storing the mold cuz you can't justify throwing that much work away...

Unlimited jd

iTrader: (5)

Pretty sure there won't be much of a market for a part that requires completely cutting the cockpit out of a 12 meter and limiting cabin access to someone under 6' and 200 lbs.

scippy

iTrader: (3)

I did a "one off" male mold for my Magnum engine hatch which was missing when I bought the boat. I used 1/4" luan to get the right shape and crown framed it then plastic wrapped it to pull the piece easily after glassing the male mold (built it exactly as if it were the part but left it 3/8" shy around the perimeter................fit like a glove!

502ss

iTrader: (3)

i would agree that it seems like for those items it would make more sense to just build out of plywood or starboard and then glass it after! I would think the biggest benefit of a mold is for production runs

glassdave

iTrader: (1)

the biggest problem with lofting a one off part is laminate continuity and uniformity in the final part. It can be done but it takes a bit of planing, you have to take a lot of care with edges and joints. Ive done them both ways, it just depends on how rough a service life the final part is gonna have.

Unlimited jd

iTrader: (5)

Did an experiment last night, had to fill a hole in a engine hatch from a cruiser, so I taped a piece of wax paper over the hole and then Formica over that, cut a piece of core to go in the hole, put some csm down then core then 1708 over it, when I flipped it this morning the wax paper side just needs a light sand and paint. I get it now. Keeping the dash flat without the mold would be tough or a lot of long board sanding.