Thank you all...

General Composites Discussions Showcase
#12

Items I used on the parts:
wax & PVA
50/50 Duratec/clear gel coat. 2 coats (I let it harden to the point that it will hold the load of the fabric pulling itself off the mold and thick enough that it would stay in place and not separate from the mold and pva.)
some spots needed super 77.
I did a second layer of texalium with scraps and super 77(helps where the fabric stretches and clears out) on some parts another layer of glass.
Then I put in cont. strand mat for bulk and flow media.
Infused it with Silmar 249. thinned 10%
Then trim and sand with 400.
cleared with PPG clear coat.

I had to do the gel coat more then once on some of the items i.e. the layer was to thin ans separated or I ran it ect.
Fender, 1 mold
front, 3 molds. small area on the center underside, area the headlights fit into, and one big one for the rest.
Tail, 2 Molds.
Side covers, 1
Air box covers, 1
I have not tried making molds that bolt together yet I just make a reference (cut) line on the mold.

#13

Have some non Hexel silver Eglass, and found that its very easy to work with, and with care can be hand laminated with no need for infusion. Here in the UK there is clear gel-coat and resin system intended for manufacture of doors, which I think might be ideal for making these type of parts.

Chris

#14

really nice professional job! Very encouraging, keep up the great work!

#15

what does 50/50 duratec/clear coat mean?

#16

for the gel coat layer, I used a mix of 50% duratec clear high gloss and 50% clear gel coat.

#17

Did you use some of the Silmar 249 as the clear gel coat?

#18

Is this the same as “aluminized fiberglass” or is this something different?

#19

no silmar 249 in the gel coat, just the duratec and the clear metal flake gelcoat (with no metal flake added) mixed up.

Yes, it is the aluminized fiberglass (texalium)

#20

With this system did you find a problem with brittleness around mounting points?

#21

In one spot on the tail on a mount screw under the seat cracked (on the seam down the middle) but it was not just the gel coat I had to much material built up and didn’t sand it flat so it was not sitting flush with the mounting point (I added 2 layers at all the mount points). I know the fenders crack on bikes this one has rubber grommets around the mount holes with metal sleeves that take the torque of the screw.

For the most part the parts are very flexible, for some reason (I have no clue why) when I did the clear the parts tend to “loosen” up a but. I used PPG 2021 clear high $ but good stuff.

Did my 150mph test (at a Popper place) and no problems. R&D is a blast LOL.

#22

Finished it up, tank paint and turn signals

#23

Tank paint and turn signals finished.

#24

tank paint

#25

Turn signals are 6 LED’s 2 for running lights, 4 for the signals. Made a clay plug and made the mold. Wired up the LED’s and droped them in the mold with 2 screws for mounting, then filled it with Silmar 249.

#26

now doing some research…what is up with “sanding aid” for this Silmar stuff? Do I need it for a cast part? Also, would any other “casting resin” work as well? (UV protective of course)

#27

The sanding aid (wax) rises to the top to form a layer to block air from the resin so it can fully cure.

After the resin is rather solid I just spray a thick layer of PVA over the exposed area to seal it up.

The resin I used was the surf board layup resin, so I dont know about the casting resin, never used it.

#28

Ha, I was actually wondering about what the top of the part looks like, but the wax woould be on the bottom of the part anyway, who cares!!

Still…I’m confused. Isn’t PVA water-soluable? Wouldn’t that er…oh i’m just confused.

#29

Did you have any trouble with bubbles in the casting?

#30

riff,
the sanding aid “wax” I was refering to is added to the resin when you mix it up and as the resin set’s up the sanding aid works its way to the surface to form a layer, not the mold wax. I got some from US composites but I have not used it. They have some info on it.

snocutt,
no problem with bubbles. I just mixed the resin nice and slow to not get any bubbles in the resin when its in the mixing cup, and into the mold nice and slow also.

#31

Great work! I hope to also do something very similar to this one day for my RC51. Although I have yet to even hold a piece of CF or anything lese in my hand, I am still in the reading phase. Just trying to learn about everything I can.

How much experience do you have with working with composites?