Quick question Does anyone know if Ducati 900ss-sl 92-98 fairings are made from fibreglass or plastic, need to repair a couple of small cracks and want to do the job properly. Many thanks and happy Christmas to all you Ducati and other bike owners out there.
Scratch and sniff.........that's the easiest way to tell if it is glassfibre or not....(apart from the white powder and the stringy bits). AL
After mine travelled down the road on it's side they were White and the vents were flat I'm guessing fibreglass
yes they are fibre glass they are press moulded with lots of chalk in the resin to act as a bulking agent press moulded means there are two mould one for outside one for the inside to get the smooth inside surface not quite as simple to repair as a hand lay up like aftermarket but doable l have found you need to grind behind the cracks deeper and wider to get good adhesion merry xmas to all Steve
Thanks Steve Have you used epoxy to repair ? I realise that grinding back is the best way to go then reapir with mat and resin , then a little fine filler .
epoxy works well Simon wasnt trying to teach granny to suck eggs it just that it needs deeper grinding to find the mat because of the bulking agent in the resin Steve
Sim, the fairings are SMC plastic, which is where the powdery chalk comes from - it's binder powder which when the part gets press moulded it heats up enough to bind together and create a nice smooth surface on the top. (car boot lids are made from the stuff). treat it like any plastic repair. If the crack doesn't go all the way through you can do two things, and that is mix some epoxy resin, open the crack slightly and dribble a load in. The resin will get into the recesses and them when you relax the panel it closes up. then you can finish with a very fine matt (tissue) or some filler. the other option is to grind out the crack till it's no more and do a laminate repair building fibreglass matt and resin up, and when dry sanding back and finishing with filler. If the panel is slit, then again try to join the split with resin first and when this has dried attempt a fibre repair on the area to strengthen it as you would a partial crack. enjoy.
That's interesting Sev........I have a very early OEM half fairing and it is definitely glassfibre...........the 1997 OEM full fairing probebly isn't......Taking a guess, perhaps early fairings were glassfibre and the later ones weren't. AL
glad you replied AL as I nearly did, treading carefully here, maybe Sev is in this trade? - I used to be trade 'hands on' at one stage and drew up parts made from glass fibre later on in life - It's down to the terms we use and I know some people refer to 'glass fibre/ fibreglass' as plastic but you and I would use the term glassfibre maybe because of our age? To me, if it has cris-cross strands that are often white and flexible before saturated with resin then I would call it glassfibre and I know Steve B and Sev talked about the 'chalky' powder that is added additionally which is a later procedure than I have had little experience with - it ensures a more consistent finish and a much skimpier gauge is achievable compared to the (often hand-applied) Gelcoat that i remember using. Also I can fairly successfully weld a 'plastic' fairing panel usually whereas it just wouldn't work with our 'fibreglass' panels. So possibly just down to different terms used here.
that probably wouldn't surprise me at all Al. GRP is cheaper than SMC by a long way, but you can't get production volume out of it at any great speed. SMC is heated press, so you have a male and female tool which is preheated and just clamps together, melting the binder powder that's in the fibre sheet itself. You can generally tell SMC as on the inside surface you'll generally have part numbers and info in relief of the part, and the fact the panels are over 3mm thick is a good indicator. 3mm of glass and resin is a lot of panel. Also when the panel splits is another way of spotting the difference; with fibreglass the break will be less powdery than an smc panel, and you'll get more glass fibres showing. The resin will be a bit more translucent. An smc panel breaks and goes all fibrous and powdery - its as if the panel was dry. The repair strategy is the same for both, but its just a bit more of a pain with smc stuff.
For plastic and glassfibre and the stuff that Sev mentions, I have tried repairs with resin and mat patch, and also with a mat patch.....Not always successful. I get far better results with Araldite (the slow cure one) particularly with splits / cracks by grooving the crack both sides quite deep, and drilling 2mm - 3mm dia holes at 6mm - 10mm intervals along the crack so they go right through the panel. I then tape over one side (usually the outside) and inject a liberal amount of Araldite with a syringe into each hole.....when it is all injected and blobby, I put the panel somewehere warm, because Araldite runs.....it goes right along and through the crack.......Sometimes if the repair isn't visble from the inside, I add an aluminium small mesh patch across it and stipple Araldite into it so that it bonds to the already roughened surface Rub down and tidy up with filler afterwards etc etc. Never had one break yet............I have tried the same with resin and it wasn't as good and air bubbles didn't seem to fill in. Results on plastic.....not quite as strong as I would like it. Experimented with a repair to carbon fibre using resin.......not a good result, only a mechanical bond, but with Araldite which is epoxy, no problem...seems to be a chemical bond. AL
@SteveB ; Exactly that Steve. Clio's had the same material for their body panels and nearly all car makers use them for siple shapes like bootlids and sometimes front fenders. It works out cheap to manufacture in high volume, but not viable in low volume as the press tools cost tens of thousands, but they can smash the parts out at little cost, and can do stuff like put stand offs for fixings and clips all in one go. However when they smash up, you may as well replace rather than attempt to repair as the material relies on heat to melt the binder powder (the chalky stuff). once the panel's cracked the damaged area just looks powdery and fibrous, whereas if there had been resin in that item it would have snapped or sheared and provided you with the possibility of repair. @Chris ; I totally agree Chris, its commonly called fibreglass because people see it as white and powdery. In fact I thought it was at first. Expanding on what you have said I've known people to call woven glass 'white carbon fibre' because they associate fibreglass with chopstrand matt, the thought it can be woven is totally unknown to them. There have been a lot of parts sold as carbon which I've seen that are actually black pigmented woven glass, you'd never know unless you look at the stuff all day. The chalky powder is a binder, which is inherent in the material from the beginning, it's dusted on after the weave has finished and then rolled up. However, in glass fibre laminating you may remember microspheres and fillite, both very fine powder which is added to the resin in order to bulk it out. You'd often use it to create a paste to fill awkward corners or areas (bodging). The gelcoat layer is still used and it's very much a thing which is done as I'm sure you remember to stop the chopped strand fibreglass matt from giving a poor surface. Also gelcoat is used to provide a substrate which can be cut back and polished in its own right - precoloured race fairings anyone? In order to stop coarse fibres printing through you might have also used a tissue layer at the beginning and end of the layup. Also remember that as far as resins go, we have two main varieties of interest to us, polyester and epoxy. Polyester resin is the traditional grp resin, smells like bodyfiller (the styrene) and horrible to work with. - but it and chop strand matt are cheap. and most body repair is lashed up with this stuff. Epoxy resin, the preferred weapon of choice. Two parts, resin and hardner, and is generally used with woven matt or other fabric. If I was going to keep some resin for repairs, it would have to be epoxy. As far as repairs are concerned, as Arquebus mentioned, don't discount epoxy adhesives. You can still 'wet' out a peice of fabric with araldite or similar epoxy adhesive and providing you get it all wetted out properly will make a great reinforcement (even a bit of old cotton or linen cloth). Adhesives are different to resins in that they have body to them which is why Al, you probably found your adhesive repairs far more satisfactory. Resin is brittle on its own, cracking easily and shattering. when you make a composite with it though it becomes fiercly strong. You can repair polyester resin items (glassfibre products) with epoxy to great effect, but not the other way around. Al, the carbon parts if cured properly, will only ever provide a mechanical bond. Now, were you to cover the area in araldite, and then say while it was still tacky (so you could still leave a fingerprint in it, but remove your finger without it sticking on) then laminated a patch using epoxy resin, then it would be a mechanical bond. Surface prep as I'm sure you know is everything. Clean out the area of debris and open up the wound so to speak, abrade the area with wet and dry and then clean it out with brake cleaner thoroughly and let it flash off. Once you've done that you're good to go with your patches. In the case of plastic, you're better off using adhesive as you've done - resin doesn't really do a lot. When I get home tonight I'll have a look at our fairings again, the superlight seat I have is fibreglass, that much I know. So I suppose it stands to reason that the fairing sides might be the same. Soon as I see the inside I'll know
Thanks Sev I know my seat is fibreglass and that will be getting a traditional epoxy layered repair , theres a small crack near one of the front fixing holes. Just bought a mint set of fairing from a later model with the twin air ducts , so will use this on my MK1 to aid rear cylinder cooling, I can then look at the original panels.
superlight seats are hand laid fibreglass oem and aftermarket fairings are SMC sev thanks for the info brought back loads of stuff i had forgotten l knew
Gonna track down the chap who used to do the seats for me in the past not going to be K&Q buttoned this time LOL Steve
