I am going to make a new mould and wondered if there was a cheaper way than what I am doing at the minute. I am doing resin infusion with epoxy resin. My mould at the minute is tooling gel coat with fibre glass putty on the back but it seems a lot of money to me. Is normal fibre glass backing cheaper if so what kind of fibre glass do I need to use? Thanks.:rolleyes2:
glass fiber putty? the entire mold is this material? yeah, that will be expensive! You can gel coat your part (plug/tool/whatever you want to call the original part) with flanges and all…then lay up layers of fiberglass and resin. There are tooling resins that are strong and will withstand the abuses of mold making. I’m sure others will chime in on what resins they use.
The point of the mold is to make it strong enough that it will not bend when vacuum bagging it. So you can make it with a few layers of glass, add a core (glass mat, balsawood, coremat, etc), and a few more layers of glass. Should be strong then.
Larger molds, people add in wooden stringers to support the structure.
yes fibre glass putty its like putty with bits of fibre glass in it that you can put on the back of moulds 20mm thick but its a lot of money. What type of fibre glass do you use? If i use epoxy gel coat do I have to use epoxy resin on the fibre glass backing?
Use a polyester tooling gel coat, then back it up with CSM using a polyester tooling resin. That will be plenty good enough for any infusion.
I would think that would be far cheaper than your putty that your using, it sounds like a rather expensive way to make a mould esp if it is a large mould.
does it matter if I am using epoxy resin for my infusion?
you can use any glass. fine 8oz, or heavy 24oz. I would use a fine weave for the first few layers of the mold, then heavy stuff, or even random mat. You are not worrying about weight, just total rigidity.
Does it matter if I use polyurethane tooling gelcoat or do I have to use epoxy gelcoat for epoxy parts? Some guy told me I had to use epoxy gelcoat thats all.
you do not have to have an epoxy mould to make a laminate using epoxy. strickly speaking you dont have to use tooling getcoat either, but the tool (mould) will last much longer if it is made from a tooling gelcoat.
probably what the guy ment was if you use a polyester gelcoat it should be reinforced with polyester resin. if you use an epoxy gelcoat it thould be reinforced with a epoxy resin. Ie dont mix the resin types in the same laminate.
I’m guessing you have started out with the ‘Carbonmods’ moulkd making kit that comes with the putty ready to go - just add hardener.
Its a good kit and in my limited experience a useful place to start, but I only used it a few times.
I made a few moulds using their tooling gelcoat and then laid up my own fibreglass backing to form the mould, which is pretty straightforward and significantly cheaper.
There are plenty of places on the web that sell firbreglass supplies.
Also, I’ve found you can buy th etooling gelcoat elsewheer and its also quite a bit cheaper.
Lol your right carbonmods is where I got it from. Where are good places in the UK to get you stuff from? Thanks again you guys are a big help:rolleyes2::rolleyes2::rolleyes2:
East coast fibreglass are good, fair prices and Gary there is very helpful. I buy a lot of stuff from them. average order I place with them is prob £800-£1000, so they must be good or I wouldnt keep going back to them!
Matrix is a place to start. (www.mcmc-uk.com)
You can perfectly make an epoxy part in a polyester mould.
East Coast Fibre Glass supplies - www.ecfibreglasssupplies.co.uk
seem to be the cheapest from my limited experience
Yes they are very good in the uk. They are continually adding new product lines aswel.
Saying that i dont buy my epoxy from them. I prefer the stuff from polyfibre. The slow hardener gives me a seven hour work life at uk workshop temps. Has a tg of over 185’c and with at Cook at 45’c. Is cured in 24 hours
What’s the viscosity? Low enough for infusion?
Can you direct me to a datasheet?
Not sure what ive done with the data sheet it may be on there website
EL68 resin and EHA77 Hardener. There website is www.polyfibre.co.uk
sorry i got the tg wrong its 150’c. But i have used it on applications well above that and it has been totally fine and not had any problems with it.
Thanks Matvd!