Introducing - Voodoo Auto Kits.

[AshG]

Originally Posted by MikeB

its less labour as Mark says, I'm no expert but with a traditional mould you have to apply the resin by hand then layer the FG then layer etc, very messy.

Where as with bagging it you lay the FG in the mold seal it in a big vacuum bag and use a pump to suck all the air out. The difference in pressure between the atomosphere and zero pressure vacuum is used to pull resin through the FG. If you get it right it can save time and up quality.

yep thats all well and good but you need a significant amount of heat to set of the curing process on prepreg, the nature of its design is that you warm it up to make it flexible to shape into the mould then you bag it, stick it in the oven which starts the curing reaction. the epoxy is already in the matting the vacuum have very little effect on pulling the resin through as its already in the matting, the true reason for vacuum bagging is that it pulls the matting right into the mould and eliminates all the micro air bubbles in the resin. (epoxys are very prone to bubbling). if you don't need the ultimate strength in the part you are much better off using a polyurethane resin as its a lot less prone to problems.

[MarkB]

Originally Posted by AshG

yep thats all well and good but you need a significant amount of heat to set of the curing process on prepreg, the nature of its design is that you warm it up to make it flexible to shape into the mould then you bag it, stick it in the oven which starts the curing reaction. the epoxy is already in the matting the vacuum have very little effect on pulling the resin through as its already in the matting, the true reason for vacuum bagging is that it pulls the matting right into the mould and eliminates all the micro air bubbles in the resin. (epoxys are very prone to bubbling). if you don't need the ultimate strength in the part you are much better off using a polyurethane resin as its a lot less prone to problems.

It's not going to be prepreg as nobody will pay the price for what is essentially a budget Kit Car. I used that as an example of how the resin infusion process works.....it's bagged then a pump draws the resin through the mould creating an even spread of resin.

Never was any good at explaining myself....

[MarkB]

The other beast may well be prepreg though as that's not a budget car and unlike anything else so nowt to compare it to...

All in all there are 4 on the go so hope they don't get mixed up with each other......

[jmh]

Hi,

If you are going down the route of resin infusion, have you looked into carbon fibre rolls (not the pre-preg stuff)?

I had a look into this about 6 to 8 months ago as I fancied doing the bodywork out of CF, but the time it was going to take to do the moulds really put me off. However, it would be more than possible to make very good products with just CF weave on a roll - if you all ready have the moulds and resin infusion kit.

Just a thought, because I think that would be really really cool.

There is a company near me that sells all of the gear to do it too (vacuum pump etc. etc.) and no need to be able to heat it up either.

Good luck with the venture ..... sounds awesome

Another benefit to resin infusion is that you can use much less resin and make the parts lighter as a result compared to wet lay.

[MarkB]

Originally Posted by jmh

Hi,

If you are going down the route of resin infusion, have you looked into carbon fibre rolls (not the pre-preg stuff)?

I had a look into this about 6 to 8 months ago as I fancied doing the bodywork out of CF, but the time it was going to take to do the moulds really put me off. However, it would be more than possible to make very good products with just CF weave on a roll - if you all ready have the moulds and resin infusion kit.

Just a thought, because I think that would be really really cool.

There is a company near me that sells all of the gear to do it too (vacuum pump etc. etc.) and no need to be able to heat it up either.

Good luck with the venture ..... sounds awesome

Another benefit to resin infusion is that you can use much less resin and make the parts lighter as a result compared to wet lay.

There is a down side to using carbon fibre.....it costs a damn fortune and unless down right it looks awful.