So I'm going to replace the big heavy steel fender on my bike with a nice, lightweight fiberglass version. I have one mold off of the fender where I covered it with blue painter's tape, but the finish isn't the best. (Still a fibernoob) Is there any reason I can't just wax the shit out of the fender and take a mold right off of the chrome itself? Surface isn't perfect but with enough wax it should be pretty smooth. I wouldn't think it'd stick too bad but I don't want to end up with a trash fender...
Making fiberglass mold off of chrome?
- Thread starter 1chrisb
- Start date
Steve F
Been Around the Block
When I made a front fender I just mocked it up straight on a spare wheel and tyre. For a one off I didn't think it was worth the extra expense of making a mold especially if you plan to customise it at the same time. Just takes a bit more sanding and a little filling as the surface wont be perfect when building up the outside surface.
Came up nice
Cheers
Steve
Came up nice
Cheers
Steve
carbon moto
manufacturer of quality cafe racer parts
hope i can give a few tips which i have picked up over the years
if the mould is not perfect no matter what you do with it the new part will not be prefect.
the part you mate is an EXACT copy from the mould.
dont bother with pva i havent used it for years still have a gallon sitting around the shop.
we use mould release wax 5 layers left to dry then polished before adding the next.
Why not wax up the original & take a mould from it then it will be right, you wont damage it if its well waxed, we paint the plugs with 2 pack paint leave them 48 hours to dry (first 12 in a heated booth) then wax & take a mould (some of these plugs have had 10 moulds taken off them with no problems (&more to come when needed)
the finished item is only as good as the mould.
I wouldnt bother with bagging fibre glass as polyester resin can easily boil if the vacuum is not regulated properly (regulators are around £140 in the uk)the consumables are another expense & it takes a lot longer, then if you dont get 100% vacuum you spend the next hour trying to find the leak.
learn to work with fibre glass properly (play with it & dont be affraid to experiment )& you wont need to bag (the only advantage is it removes excess resin so is lighter & slightly stronger - but that will come with experience)
We do use vac bagging for carbon fibre as epoxy resin is better to vac & the product is better quality
hope this helps
tony
if the mould is not perfect no matter what you do with it the new part will not be prefect.
the part you mate is an EXACT copy from the mould.
dont bother with pva i havent used it for years still have a gallon sitting around the shop.
we use mould release wax 5 layers left to dry then polished before adding the next.
Why not wax up the original & take a mould from it then it will be right, you wont damage it if its well waxed, we paint the plugs with 2 pack paint leave them 48 hours to dry (first 12 in a heated booth) then wax & take a mould (some of these plugs have had 10 moulds taken off them with no problems (&more to come when needed)
the finished item is only as good as the mould.
I wouldnt bother with bagging fibre glass as polyester resin can easily boil if the vacuum is not regulated properly (regulators are around £140 in the uk)the consumables are another expense & it takes a lot longer, then if you dont get 100% vacuum you spend the next hour trying to find the leak.
learn to work with fibre glass properly (play with it & dont be affraid to experiment )& you wont need to bag (the only advantage is it removes excess resin so is lighter & slightly stronger - but that will come with experience)
We do use vac bagging for carbon fibre as epoxy resin is better to vac & the product is better quality
hope this helps
tony
The problem is I have some modifications from the stock fender, and it has the little wire keeper clips on it. There's a slight divot to clear the curve of the seat bottom.
I already have a vac kit on the way from West Systems. I want to vac bag as I'm using WS epoxy resin as well, want a lighter part with a better finish, and there's less chance of the glass sagging away from the mold due to gravity. I like using the epoxy better as it provides a longer working time, doesn't stink to high heaven, and is much easier to work with.
Thanks for your tips!
I already have a vac kit on the way from West Systems. I want to vac bag as I'm using WS epoxy resin as well, want a lighter part with a better finish, and there's less chance of the glass sagging away from the mold due to gravity. I like using the epoxy better as it provides a longer working time, doesn't stink to high heaven, and is much easier to work with.
Thanks for your tips!
carbon moto
manufacturer of quality cafe racer parts
yep i hear what you are saying about epoxy,but it doesnt produce a better finish & costs 10 x more.If using epoxy its a good idea to use woven mat which is like carbon fibre but out fibreglass instead of chopped strand mat (lighter & better still)
Beware with the fumes from epoxy always wear a good mask as they are very toxic.
When vac bagging make sure you have a 100% vac with no leaks or it will damage your pump,If you need any more advice just ask me
tony
Beware with the fumes from epoxy always wear a good mask as they are very toxic.
When vac bagging make sure you have a 100% vac with no leaks or it will damage your pump,If you need any more advice just ask me
tony
carbon moto
manufacturer of quality cafe racer parts
best way mate ;D
