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Brian2fast
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Group: Forum Members
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Hi All This is my first post. I've visited many times and gained lots of very helpful information over the last year so I wanted to post up some of my pics to helpfully help some other newbie. A photograph tells a thousand words so I'll try and keep the words to a minimum. I remember searching for pics of anything carbon when I was starting out. I'm sure there must be lots of people on this forum that could post more pics!  My story started when I bought a set of carbon seats and then I need support brackets, I decided to take the plunge and have a go with carbon.  This is my first attempt. Wet lay in a mould made from putty.  Made 2 of them. I remember being amazed when the first one cracked out the mould. I had a few pin holes on the surface so I clear coated them, about 8 coats! No pics of the pattern I made I'm afraid. I made it from 2mm steel plate welded into shape. Then I made the classic mistake and used rattle can paint. Then I read on this forum about the problems of doing that and before I used it to make the mould I stripped the paint off and used polyester resin (another mistake!! haha). I was very lucky and got away with it tho. The pin holes annoyed me so I decided to try a vacuum infusion. After reading and reading I took the plunge and ordered the starter kit. The next part was a pedal box cover for my Westfield. Again I made the pattern from steel and (yet again) covered it with polyester resin. Then wet sanded till the cows came home.....  Used this to make a GRP mould with the green tooling gel.  Pattern covered with tooling gel.  Few layers of fiberglass over the gel. I remember having trouble doing the gel coat on my first mould. Matt (Easycomposites) suggested doing 2 layers instead of one. Now I always do 2 thinner layers, sometimes 3 if I'm worried about a thin edge.  My first infusion. This was nerve racking! haha. I took a long time making sure I didn't have bridging in the center area. I think for me the 2 most important things for doing infusions is take your time with the position of the bag and second is don't rush to put the resin in, always do a vacuum leak test. Always.  This was the result of my first infusion. I was pleased with it and could see the potential. Making lightweight, strong, cool looking parts in my garage without relying on outside help, sounds good to me.  I had a few marks but these polished out. I had a few pin holes. It took me quite a while to figure out why I was getting these and how to stop. Now I'm quite certain that these were caused by me not degassing the resin correctly. I was always worried the resin was going to set in the pot so I looking back I didn't degas for long enough. Now I degas for about 5 minutes for about 100g of resin. Is this correct? does anybody else have comments or tips about this? My next parts I wanted to make were a full set of pedals, clutch, throttle and brake. I work in an engineering design office so there was plenty of people drawing air thru their teeth when I mentioned I was going to make a carbon brake pedal
I knew I need a nice thick lump of carbon for the pedals and I didn't know if I could do an infusion for that. I still don't know. If anybody has any pointers about doing an infusion with parts that are 18mm thick please let me know.
I decided to have a go at squashing the carbon between 2 steel moulds. I drew the clutch pedal up first on the CAD at my work, then designed the moulds around that. The 2 sides of the steel mould with the faces skinned with a layer of 1.6mm aluminium.  Alloy surface polished to death.  Fabric cut out. I had designed the pivot point of the pedal to be a lot thicker than the rest of the pedal but I wanted a smooth curve transition from one thickness to the other, no stress raiser. I did this by cutting out varying sizes of rectangles of fabric (seen to the left in the pic). I wasn't sure this would work but I decided to try.  Then I squashed the mould in a vice (nearly broke the vice) and left it for a few days.  It took a bit of work splitting open the mould because the resin goes everywhere and locks them together. You can see how the alloy has deformed around the steel plates below when it was squashed.  After a lot of cutting and shaping I ended up with these shapes. I had to make another mould for the foot plate. I cut the steel boss out of my old pedal and reused it (no going back after that, lol). I was amazed how stiff and strong the carbon was at this point.  I needed a mould for each pedal. Permagrit hole saws and files were used, really good tools. One tip for holesawing thick carbon is try not to cut right through in one. Drill a pilot then cut half way through from both sides. You get a better finish, less filing required.  I pressed in little DU glacier bearings for the pivot points. All glued together with Easycomposite structural glue, great stuff. No pics of it but I welded up a little jig to hold the brake pedal and tested it to 100kg, also jumped up and down on it from various weird angles just to convince myself it wouldn't snap. The brake pedal is 6mm thick by 50mm wide and 24mm thick at the pivot end. Does anybody think this is dodgy in anyway? Brake pedal saved 260g. The three pedals and pedalbox panel saved nearly 1kg The new seats (which I bought not made), seat brackets and harnesses saved around 12kg. Well I'm getting bored typing now. I'll post up pics of my other parts from last year and a few of what I'm making just now.  Headlights with titanium nut, bolt and stud (always wanted a bit of titanium...)  These are the coolest looking bolts I'v seen! lol. I had to cut the head of one bolt and turn it into a stud. If I was doing it again I would make the attaching tabs a little thicker, they are a bit flexy. (Pasted an MOT tho).  Split moulds for headlights. Theres never enough pictures of split moulds, haha. It took me ages to get my head around split moulds. Hopefully more experienced people will post pics of multi part moulds.  Pattern made from 2mm steel and 2 steel tubes for the seat bracket mounting I needed. Newbie mistake again by painting it with rattle can primer. I got it painted with proper 2 pack by a paintshop but it still stuck in the mould and took hours to recover by carefully scrapping the paint off the mould surface.  Made 4 of these, 1 per seat side.  Exhaust can made with high temp resin and gold heat reflective tape on the inside. Exhaust can and bracket saved 1.6kg over the old stainless steel one.  Bracket for exhaust made by squashing steel moulds together. It was a bit dogdy getting it out of the moulds because the surfaces were pretty much parallel.  My first carbon parts from last winter. I only had to scrap one part and one mould. Sorry for the massive first post. I meant to post pics last year but never got round to it. I'd love to hear any advice or comments from the experienced guys on this forum. Craig
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Brian2fast
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Group: Forum Members
Posts: 79,
Visits: 1.3K
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Hi All These are the parts I'm working on this winter. Iv got a Hayabusa engine with a separate reverse gearbox. I have decided to remove reverse to save weight and reduce transmission shunt. I have a carbon transmission tunnel panel already (not made by me) but when I remove the reverse gearlever I'll have an unwanted hole in the panel. So using this as a good excuse to make more carbon bits I drew this up on CAD. A full carbon handbrake, gearlever and curvy panel to cover the handbrake and gearlever pivot.  CAD view.  Did the handbrake first. Cut the teeth off the old handbrake and used the old spring and rod, everything else is carbon. Little DU bearings for the pivots and the black bolts are chainring bolts for a mountainbike. Handle was an infusion from a 32mm diameter mould, bonded the 2 halves together. I wanted the handle to be removable so I only have to cut a narrow slot out of the panel that will cover the handbrake mechanism. The handbrake saved nearly 0.5kg over the old steel one.  Solid carbon button cut out and shaped with a 1mm cutting disc in a grinder. Alu bolts fastening the handle in position.  Ratchet re-used from old handbrake. The pawl is carbon but the very tip is steel.  Work in progress of the gearlever. Using the same 32mm diamter handle as the handbrake. The blade of the lever is 2 plates of carbon spaced apart and glued together. the carbon lever will save nearly 0.25kg over the old steel one.
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Brian2fast
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Group: Forum Members
Posts: 79,
Visits: 1.3K
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To make the tunnel pattern I welded up the base shape first so I knew the outer dimensions were bang on before getting creative with the curves.  2mm steel with 1/2" tube for the corners.  Not very clear I'm afraid, but from the CAD model I then printed off 1:1 section slices through the curvy shape I wanted.  Each profile was spaced 1/2" from the next.  Then I used 1/2" thick foam glued together and a Permagrit sanding block to shape the curves. Car body filler layered on and sanded off.  After the struggles I had with previous patterns I had coated with polyester resin and then 2 pack paint I was really happy after I used Easycomposites pattern coat and high gloss coat. Polished it up with my machine polisher.  Last week I used a Unimould kit for the first time. Found it easy to work with and has resulted in a nice strong mould. Iv got a bit of tidying up to do before I can do an infusion.  Craig
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wildcard
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Beautiful parts, and nice write up.
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Matthieu Libeert
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Thanks for sharing and taking time to document everything! was a pleasure to read everything
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Warren (Staff)
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Group: Administrators
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Some brilliant work here! especially the fine detail and the insane obsession with using as much carbon as possible on the pedal box and handbrake set up! Awesome!
The paranoia in me would recommend the usage of a couple of layers of kevlar in the layup for something like a pedal box to add a bit more impact resistance and help avoid cracks but your testing seems to have been pretty robust!!
You and I both can see the parts are pretty likely to be very strong (and certainly stronger than some of the cheaper aftermarket ones) but i do wonder what some of the IVA and MoT testers would make of it?
Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant
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TomDesign
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Brian2fast
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Group: Forum Members
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Thanks for the nice comments. Warren. I'v never used kevlar before. Would a few layers reduce the risk of cracking or is it just for keeping things together for longer after cracks do appear? I know what you mean about the IVA and MOT people. I suspect an IVA person would fail it. I searched through the guide book but couldn't see anything relating to actual load requirements. I think I found an American government paper that stated 100kg for the brake pedal. My car was SVA'd 10 years and I'm quite friendly with my MOT man..... Craig
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Hanaldo
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Group: Forum Members
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This is beautiful work. Your stuff with split moulds intrigues me. May I ask how you bonded everything together afterwards? Ie. your handbrake shaft and the headlights both have near seamless joins, did you bond them together and then sand them back and clear coat?
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Warren (Staff)
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Group: Administrators
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Kevlar adds impact resistance to a laminate so a few layers of kevlar would overall allow a little more impact/flex before failure. Of course when it does eventually fail, the very strong nature of the kevlar fibres means it will stay in one piece.
The problem with IVA/SVA and to an extent MoT is that a lot of the stuff around construction and materials used is very vague with lots of "opinion" on it being of "sound construction". So you are relying on the tester haveing a bit of knowledge, which they will on conventional materials but carbon is a bit specialist so you can understand the hesistancy.
Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant
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