Material thicknesses

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Material thicknesses

Author	Message
ajb100	ajb100 posted 13 Years Ago HOT Topic Details
Group: Forum Members Posts: 346, Visits: 4.4K	I'm currently working on a project of making a CF roof skin as a replacement to the original. The original will be cut out leaving a flange around the edge and the CF one will be bonded to this flange. This is the first time I've made a part which needs to fit over something, they've all been replacement parts until now so I've no experience in having to work out material offsets etc for the mould The current plan is to to use wax sheet over the original roof, smooth out the joins with aluminium tape, flat back any high spots, then have a paint layer over for the glossy finish for the mould to be taken off. Can anyone see an issue with that? The second thing is what thickness sheet wax will I need? Due to its width, I'll have to use 200g 1.25m rolls. There will be 5 layers of this at the edges were its on the flange so it's this thickness I need to know, even roughly as a guide. Thanks in advance
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neilb	neilb posted 13 Years Ago HOT Post Details
Group: Forum Members Posts: 107, Visits: 503	what car is this for? does the car have a seperate centre roof skin ie: with a roof moulding along each edge to cover the join? if so i would take a mould direct from the roof, then drill off the original roof and replace with the cf one. i wouldn't mess around with wax sheet on such a large area. we curently have a couple of m3's in at work which have cf roofs on them and they do flex a little when pressed, these are bonded directly to the shell and the two mouldings fitted along the sides to cover the join. bmw do have a special glue they use to bond the cf roof to the car along with some fancy clamps made just for the job. i was thinking of using a layering it:- cf,foam core,cf and at the edges an extra 3 layers of cf tape, not sure if that would be sufficient.
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ajb100	ajb100 posted 13 Years Ago HOT Post Details
Group: Forum Members Posts: 346, Visits: 4.4K	It's for a mk1 golf. Unfortunately the roof skin is massive pressing on it and is joined at the edges by folding over the side panels to form the gutters whilst at the front and back it's spot welded under the windscreen rubber and inside the boot shut so a direct replacemt would be virtually impossible. Golf roofs are ridiculously flimsy so anything would be an improvement!! This will be 3 cf 2mm foam core and then 2 cf. the extra thickness will be hidden inside the car whilst not building up the edges will make it easier to blend into the car. Once I stopped being blind, I saw EC actually list the thickness!! They say .28-.3 mm so that would give approx 1.5mm thickness plus the clear gel coat do 2mm wax sheet would be needed. Is there a better alternative to the 600x300 sheet that EC sell for such a large area?
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neilb	neilb posted 13 Years Ago HOT Post Details
Group: Forum Members Posts: 107, Visits: 503	been a long time since i worked on a mk1 golf lol. personally i would take the mould into the gutter and use that edge to bond to the shell, going into the tailgate aperture is not a problem just remove the tailgate. as for the front screen pillar's there is a factory join near the gutter line which is brazed, once the replacement skin is made you could clean off the original skin along with the brazed joint and bond to that as it would give you a nice flush fit with the screen pillar. do you have the gti/campaign screen pillar moldings? they would look pretty cool in cf also, good luck with dub should look pretty cool Edited 13 Years Ago by neilb
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ajb100	ajb100 posted 13 Years Ago HOT Post Details
Group: Forum Members Posts: 346, Visits: 4.4K	Haha, it's older than me! Still love it though. Having the pattern is no problem as I have a non sunroof roof ready to go, have cut the gutters off as there was a returned edge and will make it easier to attach the flanges. I just didn't know if using wax sheet over such an area would be a good idea? Like I say, it will be covered in aluminium tape, keyed and painted to give a gloss finnish, does this sound like it will work? I do have a set of a polled covers in a cuboard somewhere, might look into doing that as I have some mould makin putty I need to use up!
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neilb	neilb posted 13 Years Ago HOT Post Details
Group: Forum Members Posts: 107, Visits: 503	the wax sheet will work to give you a part to fit over the edges of the original roof, i think it would be a lot easier to mould the roof then replace the whole thing. the returned edge along the gutter would really be in the way for either way, would have been nice to keep it though, maybe just bent it out of the way then tapped it back with a hammer and dolly. good luck with it dude, i've seen it done on mk4 escorts
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