Carbon Fiber Bodywork

well thats half the battle won right there. its a lot easier to fix when u know what the problem is.
Good luck on round 2.

you are too good to me adam :silly: !

leon

Adam, what was the final weight on that fiberglass tail piece? I'm just waiting for mine to cure up a bit more before I pop it out. I'm thinking about vacuum bagging the next one, the last two layers on the layup ended up with many tiny bubbles that I couldn't get out. A friend of my has some vacuum stuff that he is willing to let me borrow, but it needs a few things to be a complete setup. I'm trying to decide if its worth the trouble/money of messing around with the vacuum setup considering I'm going to end up painting it and you'll never see them, and I doubt the small bubbles will have much of an affect on the overall strength.

I was also reading about this stuff called Stretchlon that is used instead of the standard Polyethelene bag. You dont need to create pleates to get pressure where you need it, it just stretches. Thought you might be interested...

-Vic

DoctoRot wrote: ..... I was also reading about this stuff called Stretchlon that is used instead of the standard Polyethelene bag. You dont need to create pleates to get pressure where you need it, it just stretches. Thought you might be interested...

-Vic

and it comes in a variety of colors and patterns...... :whistle:

As far as the strechalon goes Vic, I do have some, and I have used it. You're right, it does not require pleats like a poly bag, but it doesn't stretch quite like its advertised. In the tail mould, it would have worked good since I only needed a tiny bit more reach. When I used it on my tank moulds though, it didn't stretch enough and left thick pockets of resin in the hard to reach spots. See, too much force is used up in making the bag stretch and conform, so less force is applied to the laminate. So even with strechalon some pleats are needed. It was a curiosity when I did my tank bottom, but it was an expensive mistake when I did the first tank top.

As far as my new tail is concerned, the current weight is 15.8oz. I haven't trimmed it down yet, but the tail is incomplete too. It does not have the tool tray or rear mount yet. Tiny air bubbles wont hurt anything in a non structural part, so don't sweat it. Fyi though, vacuum bagging won't get all the air bubbles out for you either. Vacuum baggings prime job is consolidation of the layers, and squeezing all the excess resin out of the layup. This is what makes a light, strong part. All the little air bubbles can and do get trapped of you don't work them out by hand before you bag the part. Its one of the reasons I moved toward infusion. Lets see that bad boy Docto Vic!

That brings me to a request from KZR members. Does anyone have a broken or otherwise trashed Z1 tail they are willing to part with? To complete the tail, I have to make 2 more moulds of the underside, and cut out the 45 braces on rear mount to do it. I didn't want to destroy a good Z1 tail to do this......... so if anyone has one that is already damaged, that would be ideal!

Adam

When you say "tail", you mean just the bodywork, yea? I have a 79kz650. I dont really need/want the bodywork. Lemme know.

Oops, you said Z1, sorry.

sweetbro wrote: When you say "tail", you mean just the bodywork, yea? I have a 79kz650. I dont really need/want the bodywork. Lemme know.

That is a very generous offer Sweetbro. Even though I need a Z1 tail, I appreciate the sentiment to help

Adam

Z1 tails are somewhat cheap on ebay- 25-30. kz10006 might have an abused one .

Ok so first tail is a bust. Something weird happened with the gel coat, looks like gator skin.


What I'm guessing happened was, the gel coat was thicker there because it wanted to pool in the low areas, making it less cured than the rest of the mold when I put the first layer of resin on, and it pulled up when I was laying in the mat. I don't really know, I didn't notice that happen when i was laying in the mat. Other than that it actually came out pretty good. I turned the PSI up on my gun to get better atomization of the PVA this time and there is almost no orange peel, and the piece came out easily of the mold. It also fits great. I was concerned that I had gotten a little to aggressive with sanding the plug and that once laminated it might be too thick to fit on, its a little snug, but it sits on there very nicely. Weight trimmed is 3#5oz. Not very light, but that was never really something i was worried about. I need to buy some more resin, this time i think i might go with epoxy and get some cloth instead of all chopped mat. I'm still trying to decide if i want to vacuum bag, the main attraction at this point is that It will be slightly thinner than this one, which would be the difference between a good fit and a perfect fit. I was reading about infusion, but it just seems like a major PITA for what i want to achieve, however for your carbon fiber pieces Adam, it seems like a must. Also, what is the cross-sectional thickness on that fiberglass tail?

-vic

Never say its a bust Vic. Each part is a learning experience. The alligatoring is a product of the gelcoat not being cured enough, and the styrene from the next coat of resin reacting with it....I think. It has happened to me on moulds, and it happened when I was impatient. When I give myself enough time to let the tooling or gelcoat fully cure, then it doesn't happen. I haven't trimmed my part yet, but I'll cut into it and give you a cross sectional thickness. Remember that unless you have an obscene number of layers of reinforcement, the majority of your weight is in resin. A high resin:reinforcement ratio increases weight and decreases strength, which is the reason I vacuuum bag my carbon layups.

Your tail came out just fine! Since you are going to paint it, the gelcoat imperfection is a non issue. It makes a little more work to prep for paint, but its not going to impact the paint job. So unless you want to make a lighter, thinner tail, I'd stick with what you have there!

Adam