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Re: Carbon question.......

Posted: Thu Feb 09, 2012 7:11 pm
by morepower
Great stuff... I was planning on doing full length for the spars as yes most of the damage would be from bars but if anyone has damage else where I will be asked why I didnt do them longer.... Cant win if you do either... But longer ones can be cut down if needed or if the customer wants to do it themselves....

I am using a good quality hybrid polycore gel coat which has some water clear casting resin added to both thin it down and add some clarity too... The resin is a very thin crystic resin which when you pour over the carbon is thin enough to see the air bubbles popping as they come to the surface.. Brilliant stuff.. It is almost infusion resin thin very watery.. I have found I dont need to lacquer the parts to get a gloss finish if the moulds are good and polished. I am doing them in a vacuum bag too as this does help consolidate the layers and as I do use more resin than I need this does also help pull the bubbles out too.... I am still learning a lot and will in the next week to 10 days be going my first pre-preg parts in the P3 Aprilia RS fairing mould. I am hoping to do a lot more pre-preg in the next 12 months and hope to do over 50% of my work with Pre-pregs... It is not always the best way for some parts as the moulds have to be a lot stronger and take heat too.. So for ease some work will always be wetlay in vacuum bags....

Re: Carbon question.......

Posted: Thu Feb 09, 2012 8:03 pm
by morepower
OH if anyone has a hugger to copy.... I will glady do one of those and offer it up for sale.......

Re: Carbon question.......

Posted: Thu Feb 09, 2012 10:52 pm
by bullitt118
Martinh wrote:Some harris ones which fit but are from another bike:
Image
That's my set that i got of ebay for £10.. & they are a perfect fit on a 3TJ :grin:
http://www.ebay.co.uk/itm/140629064777? ... 3D1&_rdc=1

Re: Carbon question.......

Posted: Thu Feb 09, 2012 11:07 pm
by Martinh
Interesting technique mp, you mention using a thin crystic resin does that mean its polyester or vinylester? I didnt think scott bader made epoxy. Also, how does the gelcoat/casting resin fair for uv resistance?

I'm sure this is getting dull for everyone else so i'll stop after that!

cheers
martin

p.s. bullit, yeah i got it from the post in the for sale section, hope you don't mind!

Re: Carbon question.......

Posted: Thu Feb 09, 2012 11:32 pm
by Evilchicken0
morepower wrote:OH if anyone has a hugger to copy.... I will glady do one of those and offer it up for sale.......
yeah ... that's the thing see nobody ever made one

Re: Carbon question.......

Posted: Thu Feb 09, 2012 11:36 pm
by Evilchicken0
Martinh wrote:I was looking into doing the same thing, but i'm glad you've got there first morepower i still need to finish my 2tk fairings not to mention a carbon bonnet for my mini marcos.

I did a little research into the frame protectors here are a few pictures of the ones i found:

The ones from boris's bike:
Image

Some harris ones which fit but are from another bike:
Image

Ones from a frame on ebay the other month (hope you don't mind ben!)
Image

And ones on a frame bdk have had for sale for a million years!
Image
.
The ones on my bike are slightly longer, they go nearer the headstock. I think they look better like that.

Re: Carbon question.......

Posted: Thu Feb 09, 2012 11:43 pm
by morepower
No problem Martin...

The resin is a polyester resin and is supposed to be better than epoxy where UV light is concerned. The clear casting resin has a refractive index which is supposed to be the same as glass and parts made using this resin are not usually lacquered to stop UV damage.

The gelcoat was reccomended by the pattern maker who is making my kit moulds at the moment and as he has had 30 years experience I thought I would use any and to be honest all the help he would offer.. He had just had a couple of 20kg tubs arrive so I had one off him to try as the stuff sold by one of the suppliers who do kits always had some bloom or bluish hew to the gelcoat... This is a lot better and after talking to one of the other suppliers I was sent 500gr of the clear casting resin to try as a freebie. It works really well.. They offered a few opinions on the ratio to mix the two resins together and after a bit of testing and playing with it on several parts I hope I have got a mix that works well and it not too brittle yet still gives good clarity..

Epoxy resins are really good but for cheap parts at prices people are willing to pay they are just too expensive. A good ultra clear epoxy starts at £38.00 per kilo so for 4 parts you have almost 500gr of resin plus up to a mitre of carbon at about £25.00 per mitre. So you are at over £40 before you have accounted for the cost of the mould, vacuum bag, peel ply, release film and mould release chemicals, breather cloth and then power for the vaccum pump ect ect... it only takes one to be scrapped and then you are playing catch up... I would rather go down the Pre-preg route if I am going to use epoxy resins as I know a supplier who do a crystal clear pre-preg material but you do need an oven.. I hope to build an 8 foot deep by 4 foot square oven in the spring. I have sourced the thermostatic controllers that will ramp up the temperature, dwell then cool to a set temp over set times to get the pre-preg to warm evenly, let the resin flow before curing then fully cure but not let the moulds cool fully as cold moulds do crack if you have a glass mould and a carbon part in that mould due to different expansion characteristics. I have seen a 1 inch thick mould for a pre-preg factory Yamaha hugger with a surface covered in cracks because it had been allowed to cool fully and that was with 2 layers of pre-preg carbon at 0.6mm thick!! So I want the oven to have fully automated control and work on thermo couples that take actual part temp not just air temp in the oven. This will not be cheap but it should allow me to make some of the best parts possible.... I may have to farm out mould making to the pattern maker... But at least I know when they are made they will be as good as I can make them....

Re: Carbon question.......

Posted: Fri Feb 10, 2012 11:00 am
by hunter
I,would go with Evil on the length,If you took them up to the cable holes in the frame, they would look better,
And if anyone would like them shorter,They could be trimmed.


Those Harris one in the pic above,Look like Kevlar. :drool:

Re: Carbon question.......

Posted: Fri Feb 10, 2012 11:16 am
by MW2K8
If nobody made a rear hugger, then how about adapting one from your exisiting stock Richard?

Matt

8-)

Re: Carbon question.......

Posted: Fri Feb 10, 2012 12:06 pm
by Taggyd
just slightly off track, but how about some covers for the engine casings, made thicker to offer a bit of protection? should be fairly simple to mould and be able to use the existing mounting bolts of the cover themselves?