Carbon Fiber / Fiberglass Bodywork

[bstewartca]

Great project... will be following from Canada eh!

[Hooligan]

Anyway, Im keen to see how you make the moulds and go about creating the panels. Im not a buyer, just a lookeyloo and keen to learn.

I have done some composites work and my father-in-law made a business out of making custom composite car parts. It is an awful business. Dusty, scratchy, toxic stuff and a ton of hard work.

[wolfeman28]

Finished ordering up supplies today, and got all of the parts off the bike. I have a tiny dent in the tank from when the bike fell over in the driveway that I will have to fix. I had tie downs still attached to the bars, and when the front rotated it pushed the hook into the tank. Insurance allotted $100 for PDR on the dent, but I took it to a shop yesterday and they can't get access with any tool because of the shield under the cap. Tried the hot/cold trick but no dice. Not going to bother trying with a hot glue puller since I know it wont work. Don't want to deal with bondo, so I may just leave it as is, since after I make the mold I'll be cutting the bottom off the tank to fix the rusty thin spots. I can pop it out easy then. I should be able to use some wax or clay before applying the gelcoat, then I can just sand out any minor blemish that will be in the mold.




Made a game plan for the molds in regards to number of pieces and where the parting lines will be. The solo seat and side covers are going to be more of a pain than I originally thought if I want to have easy removal from the molds. Seat can be done in a 3 part mold, but I might go with 4 to make it easier. Also now see that I can make molds for the solo seat brackets easy. Would be better than those mild steel ones floating around on the internet, and probably the same cost. Side cover will have to be 2 piece, with an awkward angle on the parting line. I'll need to make a tiny secondary mold of the panel mount clips, and epoxy them to the part as a last step along with the pointy tank mount pin.

My lower has some issues but I can work with it. The JL pipes I have don't clear the fairing on the bottom, but you can still get the fairing on proper with a bit of pressure against the pipes. So my lower now has humps where the pipes melted the plastic (had heat shield against it as well, didn't help it seems). I'll be using some clay to increase the size of the humps already there, which should make the new fairing clear the JLs perfectly. If anybody ends up needing me to make a lower without the clearance, I can simply use some wax or clay to plug up the humps in the mold before laying up the part.





Also found this gem of a crack in the lower. Wasn't there when I put the bike away for the winter, and I've only ridden the bike twice this year for about 2 hours. Looks like it started at one of the drain holes maybe? Maybe the stress on the fairing from the pipes, along with the cold this winter did it... Who knows. These old plastics are getting brittle, even with only 7k on them since 84.

wolfeman28, the informative and knowledgeable posts you have made are great.

I will be following this with interest.

Some folks with piles of RZ projects may be interested in some of your handy work…

Whereabouts in the world are you located?

Cleveland Ohio.
I doubt anybody will be interested in my handy work once they see the cost :)

[wolfeman28]

It is an awful business. Dusty, scratchy, toxic stuff and a ton of hard work.

Ain't that the truth.
With modern epoxies it removes a lot of the health issues that can come about, but it seems like we still can't get away from the polyester resins. It just isn't cost effective to make molds with epoxy, so I always resort to poly gelcoats and resin, just so much cheaper.
Last tank I made with carbon fiber destroyed a jigsaw and a dremel. That dust ruins everything electrical. Air/hand tools only for me now when working with CF.

[Hooligan]

My father-in-law had a dedicated shop and had to run positive air pressure mask because he spent a lot of time in there. He had clothing and shoes that never came into the house. It can be just nasty work

[Evans Ward]

That shield under the cap can be cut out with a dremel tool w/ cut off wheel to allow access for PDR tools. Additional benefit is that you’ll be able to see inside condition of tank and visualize gas level at any time.

[Evans Ward]

That shield under the cap can be cut out with a dremel tool w/ cut off wheel to allow access for PDR tools. Additional benefit is that you’ll be able to see inside condition of tank and visualize gas level at any time.

[wolfeman28]

Everything is ordered that I need. So that includes the tooling supplies listed previously, and all materials needed to make all body parts on the RZ. Lots of resin, CF/Kevlar fabric, fasteners, bagging materials, etc

Total damage- $1500

Still may need to order some more CF fabric as well, so that cost may go up. The killer on cost is the ethanol resistant epoxy for the tank. Most people are just using it as a coating to keep cost down, and I can see why. But I'm using it as the laminating resin, so it is crazy expensive. These tanks will last as long as you don't hit them with a baseball bat (or a car).

I did order up inserts for the solo seat brackets, so I will definitely be making those. For the upper fairing, I was originally going to use the stock lower mount and stock upper bracing brackets, and just rivet them back in like stock. But I changed my mind and will be making the mounts out of CF. I can't stand how most composite parts you buy require so much fabricating after you buy them. If you've ever bought anything from Airtech you know what I'm talking about. Not hating on them, as I've spent thousands on their products over the years. I just want to make a complete buy and install option with no need for people to fuss with rigging generic mounts. Yes it increases the cost by quite a bit, but at least I'll be able to take pride in my finished product.

[wolfeman28]

My test filler neck came in today. Works great! Took a tiny bit of massaging to get the cap in, but after that it goes in and out freely and turns fine. Cap will sit about 6mm taller than stock, not much I can do about that unless I want to add a crap load of extra carbon between the tank and the filler flange. As a bonus, the lock on the cap still functions as it should. With the lock engaged, you can twist the cap open, but no way it will come out.

[RuZty]

Following this with interest, I did composite motorsport work in the UK about 30 years ago and recently picked up a nice used Edwards vacuum pump to start playing around with it again. The tank is an ambitious project, but it sounds like you have given it a lot of thought. I don't recall if it's an issue with steel, but with aluminum hard points laminated into the chassis we wrapped them in fine glass fabric so there wouldn't be galvanic corrosion between it and the carbon.

[wolfeman28]

I don't recall if it's an issue with steel, but with aluminum hard points laminated into the chassis we wrapped them in fine glass fabric so there wouldn't be galvanic corrosion between it and the carbon.

Yes it's an issue, and the glass between it is exactly the way to deal with it properly :) This test filler cap is aluminum since it was a third the price of the 316 one, and didn't want to be out the cost if it didn't work. Any tank I make to sell would be stainless, which doesn't normally have any galvanic issues with carbon fiber. Aluminum and plain Jane steel on the other hand need a barrier.

[wolfeman28]

My composites supplier is being very slow on fulfilling my order. Been a week and they just printed a label today, so I assume it will be shipped out tomorrow. Hopefully Monday my crap will be delivered an I can get started.

In the meantime, I've got to work on some odds and ends. I had to build up some clay on the inside mounts on the upper fairing. It may look strange now, but after I make the molds for the mounts you will see why it had to be done this way.




I also got to work on filling in the high detail areas on the coolant/ypvs covers. I would never be able to get the hybrid fabric to pull into the small ridges on those covers. I'd be lucky to even get the mold to support those small details. In my experience, the gelcoat would end up being extremely weak in those areas and probably break apart removing it from the plug. So in goes the clay. The goal is to get it to still have some indentation, so it won't look bland on the final parts. I can only do so much with modelling clay as I am not an artist/sculptor. A bit of sanding on the gelcoat will hide any imperfections my 'finger sculpting' has made.

[evan_calgary]

10-4 man! Looks like you know what you are up to. I've seen many people attempt to build something like a tank as their first project with intent to sell and it turns out not good then they continue to try and sell them. Looks like a fairly difficult shape to mold so best of luck!

I have been building composite parts for over 20 years now covering cars, motorcycles, boats etc. So not my first rodeo :) I've designed and built my own carbon fiber PWC hulls from scratch all the way to a finished ski. Had to learn all on my own before Youtube was filled with videos on the subject (90% of which are complete hack nonsense, the other 10% being very good)

I've dealt with all types of re-enforcement fabrics before. Kevlar/aramid is a pain to work with yes, but the current hybrid weaves are not too bad as far as workability go. Hardest part with those fabrics is cutting them. Good resin coverage and ratio is important as well.

I have made tanks before that work fine. This one will have to be done in two sections, top/bottom, and then bonded. Top mold is going to be three piece, bottom mold two. No other way around it really if I want to retain all stock lines including the seam. Bonding will be done at the seam using the same epoxy used in the tank, along with Carbiso to make it more paste like. Worked on my prior 2 piece tank, so I'll stick with it. I can do the bottom in two pieces without having to remove the stock mounts. It's going to take some cleaver placement of filleting on the back side of them or else I'd never get the parts to release from the mold, but it can be done. As for the gas cap, it really is easy. I'll just be laying the first 2 layers of fabric down around the hole, filler neck goes in the hole, remaining layers on top of it. The filler neck I'm using has a nice flange on it which I will be drilling holes into, so the layers will anchor into it.

The key to getting a tank that won't eat itself to bits with modern fuel is really in the curing process. Simply letting a wet layup cure at room temperature is not enough. There have been papers written that show modern epoxies will be more resilient to ethanol when they are allowed to set at room temperature for several hours, followed by low heat post cure(I do 170deg F for 3 hours).

I'll show it all and explain further step by step as I go along with the project. Everyone can take the journey with me :p Something to add as I was thinking last night- I'm going to make a front fender mold and rear underbody mold as well. Will also be making a second mold for the upper fairing with no headlight hole, and a lower fairing piece with extended belly pan (should be large enough to meet most racing rules for fluid containment). I can only use what I have around here as guides, so it will be formed large enough to clear a set of JL pipes which should suffice for most others as well. As with all racing bodywork though, some fitting work my be required for your application.

[wolfeman28]

10-4 man! Looks like you know what you are up to. I've seen many people attempt to build something like a tank as their first project with intent to sell and it turns out not good then they continue to try and sell them. Looks like a fairly difficult shape to mold so best of luck!

Funny you should mention that, as that's the reason I built my RS250 tank. I purchased one from overseas for quite a large sum of money (over $1200) and it ended up having a few deficiencies in corners. Many pinholes, a bunch of voids where there wasn't good pressure on the fabric, etc. It was extremely thick though so I'll give the builder that. And in his defense, he sells the tanks as racing use only so they are meant to have work done before use. My OCD kicked in so I cleaned up the voids, made a mold of it, and popped out my own tank. My dad always told me, if you want anything done right do it yourself. Then if it goes south, you can only blame you.

[wolfeman28]

Sorry for the delay on posting, I only had a 2 weeks of vacation this year and used it all for this project, so things got a bit fast and furious trying to get everything done. Basically I ran into many roadblocks, as anyone who has worked with composites can tell you is very normal :) The biggest restriction has been the weather. When I started laying the tooling gel coat the temps were around 65 for 4 days straight, which isn't too bad but still not ideal, and to make it worse the humidity was over 90% for all those days. The humidity caused many issues working outside in a garage. I couldn't even get the PVA to dry with forced heating, so there were many coatings/clean/coat again/clean etc. Since I'm working out of a garage and do not have a climate controlled shop at the moment, and was pressed on time, I just had to make the best of it. The bottom mold for the tank was what I would call '50%' useable. Normally you would scrap something like that, but I decided to take the time to fix the mold and it came out ok, just wasted time. A few parts of the top mold gel coat ended up pulling away from the plug while setting up, so that had to be dealt with as well. Was able to complete the front fender, seat/tank/upper mounts, oil pump cover, clutch side cover, and tank molds. Ran out of tooling gel coat and tooling resin, so I will need about the same amount I had already ordered to get the solo seat, ypvs covers, upper and lower fairing, and side panels done. Unfortunately I am out of vacation for the year and back to work so who knows when I'll have a chance to complete those. Maybe on some random weekend days if the weather complies.

I have already laid up trial runs of a front fender and a complete tank and they came out better than expected. Minimal finishing work needed on the completed parts. Slight bridging in some spots on the tight bottom corners of the tank, which I expected would happen. Further runs won't have the problem since now I know the trouble areas to tend during layup and bagging. Did the tank with 4 layers of Carbon and am quite happy with the weight and strength. I didn't utilize the carbon/kevlar material for the trial run, and based on the result of the finished tank, I may not use it all all in future runs. The tank weighs a whopping 3 pounds complete compared to the 11 pounds of the stock tank.

I'll post up pictures and further explanation of the process so far later tonight. I tried to document everything but once the chemicals come out, the phone was out of the way so I may have missed some key things. But it will give you an idea of the scope of this project.

Teaser pic of tank. This was right after it came out of the mold, so bond lines not sanded down, PVA not cleaned off etc. Sorry for the blurry pic, I'm not a photographer.