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Discussion Starter #1
I'm getting ready start designing my cafe tail. I'm planning on using a smaill piece of 1/2 inch oak plywood(hard cabinet grade) and then hand shaping a tail out of foam and hand laying fiberglass over that. I will us a layer of plastic or wax paper to keep the resin from melting the foam. I plan on housing the battey inside so it has to be holllow. I will remove the foam and secure the tail to the base plate and then put a final coat of glass and resin. so the seat will be solid fiberglass with an oak core... I just didn't know if anyone else tride this or has an easier way.. this seems pretty simple to me? any input would be great. I tend to over complicate things, but I just thought fiberglass alone would crack under my fat butt!!!!
 

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A picture of what you're suggesting would be helpful. So are you thinking of using the oak as the base of the seat pan for your final piece?

Some foams will not melt from the resins that you're going to be using. I'd suspect that a foam core for this kind of construction would be pretty darned sturdy. Here's a polyurethane foam mix by Tap Plastics:

http://www.tapplastics.com/shop/product.php?pid=79&PHPSESSID=200710081510121148248175

You could make your part by shaping this foam, and then perhaps hollow out the tail fairing foam such that it houses your battery.

If you go with the foam you suggested earlier, you could also try wrapping the foam in packing tape and then coating this tape with PVA so that it does not stick to your layup. That ought to do better than wax-paper. For another way to get rid of the foam, check out this guy's instructable on the "lost foam" method of construction:

http://www.instructables.com/id/SM93MJWF2H0OXCZ/
 

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Discussion Starter #3
man that was really helpful. yes that is my basic idea to use the oak as a complete seat pan and fix the tails hump to it after the foam is removed. then after that is fixed to the plank, coat the entire piece, pan and all, in one coat of glass and resin. so it appears as one solid painted fiberglass unit just with a oak core? you won't see the oak it will just act as the rigid backbone inside! I think it will work and shouldn't be insanely heavy. I've pulled forty to fifty pounds off the bike so if I put 10 back with this seat I'm good with that
 

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quote:
man that was really helpful. yes that is my basic idea to use the oak as a complete seat pan and fix the tails hump to it after the foam is removed. then after that is fixed to the plank, coat the entire piece, pan and all, in one coat of glass and resin. so it appears as one solid painted fiberglass unit just with a oak core? you won't see the oak it will just act as the rigid backbone inside! I think it will work and shouldn't be insanely heavy. I've pulled forty to fifty pounds off the bike so if I put 10 back with this seat I'm good with that

That all seems sound enough to me. I bet you could use 1/4" plywood for your seatpan in the layup without compromising anything. Maybe even get a 2" hole cutter for your drill and chew a few lightening holes into the rear part of the assembly :)

Post pics when you get it together!
 

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Discussion Starter #5
yeah I switched to photobucket so I'll get some photos going in the next day or so. I just epoxied my garage floor tonight so it'll be tomorrow at least before I can move back into my work space. but that seat is numero uno on my list of git'r dones
 

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have you thought about just using the original seat pan and salvaging the factory mounting bracketry. it'll save you the effort later.

NCNR
 

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Discussion Starter #7
well I thought about it but if I use the battery box mount as secure points then it allows me to eliminate all that bulky bracketry. and securing fiberglass to a metal pan will be more difficult I thought. also I want a flat seat. if you have done it and photo's I'm always open to new ideas though. thanks for the response
 

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if you have done it and photo's I'm always open to new ideas though.
look at my cb750 in the project build forum. that's glass over foam on a chopped up metal pan. i've got process photos and i'm working on putting them all together.

...it ain't hollow, but that's not a huge deviation from the same process.


NCNR
 

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Discussion Starter #9
catboy... your bike will look nice when you get it done! however I'm going for a little bit different look. not a whole lot different. I like that saltlake, bare bones look. I want my tail to be perfecty flat with the round hump on the back. it's hard to see that when you look at MY factory seat pan. plus I have a mint condition seat and I hate to chop that up, cause I'll prolly sell that on ebay for money to buy brakes or something. and I don't really wanna buy another one just for cutting up.. so that my delema. I will start tonight on my seat pan in a day or two I should have it at least mocked up with the seat and the foam hump together... I do really like what you got going though
 
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