Fibreglassing expertise needed [Archive]

bogan

10th April 2011, 11:35

I'm after some fiberglass mat and resin etc for some custom bodywork. However the design is fiberglass reinforced thermoplastic. I've made some CNC male molds in mdf and in the process of pulling the plastic shells off them (get a really good outer surface finish and precision this way). Size is a large cowl, and largish tyre hugger. Because the fiberglass will be laid on the inside, and stay stuck to the plastic, I don't need to worry about release agents etc.

So what is a good type to use? how much should I expect to need? and where is a good place to get it from?

here's a pic of the mold
<img src="http://i285.photobucket.com/albums/ll52/bogan229/P1010505.jpg" width=640 />

Madness

10th April 2011, 17:15

Fibreglass Developments (http://www.composites.co.nz/our-company.html) in Bunnythorpe are a good bunch of buggers, FWIW.

bogan

11th April 2011, 14:49

Fibreglass Developments (http://www.composites.co.nz/our-company.html) in Bunnythorpe are a good bunch of buggers, FWIW.

might have a chat if I can't get computer-fed advice, don't really wanna go take up professionals time for such a small project.

Grubber

11th April 2011, 14:56

I'm after some fiberglass mat and resin etc for some custom bodywork. However the design is fiberglass reinforced thermoplastic. I've made some CNC male molds in mdf and in the process of pulling the plastic shells off them (get a really good outer surface finish and precision this way). Size is a large cowl, and largish tyre hugger. Because the fiberglass will be laid on the inside, and stay stuck to the plastic, I don't need to worry about release agents etc.

So what is a good type to use? how much should I expect to need? and where is a good place to get it from?

here's a pic of the mold

Jeez your keen. Do a bit of my own paint and panel work but i'm not that into it i'd make my own molds though. Well done.
I know a guy out in Waiuku that does a lot of that type of work might be able to help.Not sure! Will PM his number for ya.

CookMySock

11th April 2011, 15:37

[...] Because the fiberglass will be laid on the inside, and stay stuck to the plastic, I don't need to worry about release agents etc.Almost any fibreglassing product will do that. The hardest part will be getting it all lay down flat and smooth.

I'd look at using a cheapo basic epoxy resin, fibreglass cloth, peel ply, and vacuum bag the whole thing just enough to hold it all flat while it cures.

Epoxy coz it doesn't go off hell-quick while you are trying to juggle it all into place, and sometimes polyester stays soft for days in the cooler weather. Also some polyester is hard on some plastics, especially foamed plastics.

Cloth coz it gives a better finish - BUT you will have to cut lots of bits up and lay it into corners on the 45 degree weave to get it lay down. Spend lots of time planning before you start catalyzing resin.

Peel ply coz it just leaves a wikid az finish and its fun. You can raid your mrs' sewing bag of tricks for cloth to be used as peel ply. Any strong thin nylon/rayon-sorta fabric that goes zzzzzzip! when you run your fingernail across it will do.

Vacuum Bag coz thats about the only way you are going to get it to lay flat unless you grow another four arms.

Search youtube for bagging howto vids, and google any terms you are not familiar with, as ya do. :niceone:

bogan

12th April 2011, 21:40

My research reckons that I need 4.5m2 of powder bound CSM, and a 5L epoxy resin kit. Be putting an order in over the next few days, so if I am wrong, or if I need more shit, please let me know!

CookMySock

13th April 2011, 08:05

It isn't that CSM is "wrong", it's just that cloth makes a tidier more rewarding job and looks cool. CSM layups are like trying to shape mashed potato with chicken wire in it, whereas cloth layups pack down flat and hard.

5L sounds like a lot of resin. My guess is you won't use 1/4 of that. Remember the goal is to use the minimum possible amount of resin, and pack it all down really harrrrd, but without air bubbles.

If you do use polyester, keep your layups thin, mix small amounts of resin at a time, and keep your ambient temps down, and be ready to move fast if it starts to set. Expect to have to warm the job the next day because it didn't properly go off. You need a lot of experience to work with polyester coz it can get cranky on you with little warning. Epoxy is much more predictable, and if it's not then at least it doesn't go thermonuclear on you without warning.

Also strongly recommend you do some initial practice layups on a discarded ice cream container, to get the hang of internal and external corner layups, or else you might end up with your very cool work-of-art plug looking like it's been tar and feathered! :shutup:

And have fun! FRP is cool!

imdying

13th April 2011, 09:17

My research reckons that I need 4.5m2 of powder bound CSM, and a 5L epoxy resin kit. Be putting an order in over the next few days, so if I am wrong, or if I need more shit, please let me know!You want about a 450gsm CSM. 5 litres should be heaps. Get a metre of woven cloth to put on the inside to tidy it up.

If you do use polyester, keep your layups thin, mix small amounts of resin at a time, and keep your ambient temps down, and be ready to move fast if it starts to set. Expect to have to warm the job the next day because it didn't properly go off. You need a lot of experience to work with polyester coz it can get cranky on you with little warning. Epoxy is much more predictable, and if it's not then at least it doesn't go thermonuclear on you without warning.I think you've got them backwards mate.

Get some scales to measure your epoxy out on, it can set itself on fire if you mix it wrong, or try to mix up too much. Make sure you have somewhere to put your resin mixing container if it goes bad; I try to have a bucket with sand in it handy.

bogan

13th April 2011, 11:04

sounds like a plan, will add the cloth and put an order in.

Tell me more about this resin mixing, have got scales etc, how much do you think is a good amount to mix at a time? The resin is the most expensive bit and I'd rather not waste it...

imdying

13th April 2011, 11:35

Tell me more about this resin mixing, have got scales etc, how much do you think is a good amount to mix at a time? The resin is the most expensive bit and I'd rather not waste it...The product will come with a datasheet, you can't go wrong.

Resin/fibre ration is about 50/50, so if you're doing it right you'll use about 300gm of resin for a square metre of 300gsm CSM. You'll probably use more, but some of that will be excess left on your tools/work surface, plus you won't get a perfect fibre/resin ration without bagging it.

Make sure you have acetone on hand to clean things with. Get a couple of tall glass (pasta) jars to leave your brushes/rollers in.

It's dead easy, a three year old could glass shit up, you really can't go wrong.

imdying

13th April 2011, 11:39

bogan

13th April 2011, 13:08

That thing you've built... I would cover it in body filler, sand it back to about 120, shoot a thick layer of Duratec Surfacing primer (get it from Nuplex) over it, polish that to 2000 grit, flange the edges, flange it up the centre, mould one side, mould the other (make the centre flange bolt together, put some alignment lugs on it), then make a one piece tail from that. If you're not super anal about the surface (given you can sand the final part easily enough) then it's a piece of piss.

Yeh that sounds like the way it's usually done, but I reckon having a thermoplastic shell reinforced with fiberglass makes one-off a lot easier and quicker to produce. Also the guy/owner I flat with has a phobia about fibreglass sanding (among other things).

CookMySock

13th April 2011, 13:15

I think you've got them backwards mate.:blink: :rolleyes: :facepalm:

imdying

13th April 2011, 13:37

Yeh that sounds like the way it's usually done, but I reckon having a thermoplastic shell reinforced with fiberglass makes one-off a lot easier and quicker to produce.Sounds like fun to fix too.

Also the guy/owner I flat with has a phobia about fibreglass sanding (among other things).So, he's not sanding them is he? If you don't like sanding, stay the fuck away from eglass work :laugh:

bogan

13th April 2011, 13:42

Sounds like fun to fix too.

Fix? I don't plan on breaking them :innocent:

So, he's not sanding them is he? If you don't like sanding, stay the fuck away from eglass work :laugh:

But it's airborne, I mean, that stuff is pretty much over the counter agent orange :facepalm:

imdying

13th April 2011, 13:46

But it's airborne, I mean, that stuff is pretty much over the counter agent orange :facepalm:Ahh, land lord doesn't like the dust? Meh, respirator (can't do glass work without one, well unless you're some special sort of retard :laugh:), vacuum cleaner, mission accomplished.

Power tools rock, don't do anything by hand you can't farm out to a DA.

bogan

13th April 2011, 13:54

Ahh, land lord doesn't like the dust? Meh, respirator (can't do glass work without one, well unless you're some special sort of retard :laugh:), vacuum cleaner, mission accomplished.

Power tools rock, don't do anything by hand you can't farm out to a DA.

Yeh, reckon I'll just come in to uni and use the paint booth as it has an extractor hood (actually wonder if that just pisses it out the wall though...) to do any sanding required.

imdying

13th April 2011, 14:07

Yeh, reckon I'll just come in to uni and use the paint booth as it has an extractor hood (actually wonder if that just pisses it out the wall though...) to do any sanding required.I would be asking the bodyshop people about that before you try it! They might not want a contaminate like that in there booth!

Just sit at the bottom of the garden. It's nowhere near as bad as carbon.

bogan

13th April 2011, 14:11

I would be asking the bodyshop people about that before you try it! They might not want a contaminate like that in there booth!

Just sit at the bottom of the garden. It's nowhere near as bad as carbon.

see how it goes, apart from the joins in the plastic, I doubt there will be bugger all sanding required anyway. If i get this one sorted, I'm thinking a carbon/kevlar tank next, made the traditional way with female split molds.

CookMySock

13th April 2011, 15:50

I doubt there will be bugger all sanding required anyway.:blink::killingme </10 chars>

imdying

13th April 2011, 15:52

I'm thinking a carbon/kevlar tank next, made the traditional way with female split molds.Definitely the best choice for your first multi mold part.

bogan

13th April 2011, 16:12

:blink::killingme </10 chars>

Definitely the best choice for your first multi mold part.

what can I say, I'm an optimist :shrug:

imdying

13th April 2011, 16:39

what can I say, I'm an optimist :shrug:Carbon and kelvar has some interesting properties that you'd be better off learning about in a smaller cheaper fashion... start with a heel guard or similar.

imdying

13th April 2011, 16:41

Another member here made this for his first part:
<img src="http://imgup.co.nz/i/anonymous/1302570881-Hanger.jpg" />

He used an ester resin with a 20 min pot life, and it was the hurrying that that added that caused him to distort the weave. Rushing never helps. Still, given the propensity or 200gsm carbon dual twil to bridge over such tight radius bends, I reckon he did pretty good for a first attempt.

The three (mostly) flawless parts are Tyga.

bogan

13th April 2011, 16:55

yeh I plan on painting over it anyway, the CF finish isn't really the look I want, however asphalt black (basically a matte black with a cooler name) :drool:

point taken though, will see if there are any smaller bits I need and try them first. Think it'll be a while before I get really stuck in to composites anyway.

imdying

13th April 2011, 18:09

Well sing out when you do, you might as well learn from our mistakes instead of making them yourself :laugh:

bogan

13th April 2011, 18:19

Well sing out when you do, you might as well learn from our mistakes instead of making them yourself :laugh:

shall do, I generally find a way to make different mistakes anyway :bleh:

bogan

3rd May 2011, 18:41

Bit of hugger action to wet my whistle, so to speak. A good first part to get into glassing with I reckon, as surface imperfections will be a bit hidden, and matte black is gonna be a good color choice :D

<img src="http://i285.photobucket.com/albums/ll52/bogan229/P1010608.jpg" />

have put 200g cloth over the top of the 450g CSM, feels rigid enough, smooth but there are a few bubbles, got the shape almost sorted so mainly sanding to go.

ducatilover

3rd May 2011, 19:06

bogan

3rd May 2011, 21:55

That's something I was thinking about today during my Sociology lecture :yes: i was wondering if I should make on for the ZZR.
Be a few weeks before I can get it on the road/tuned up 'cos of the reg/rec being delivered.
I'll have to have a peek at that!

haha, riveting stuff was it! Hopefully have it done this weekend, so will let you know if it was a good plan or not. Your ZZR still has the original mudguard anyway though dunnit? I had a bit more pressure to get one on, will still flick onto the exhaust a bit, but not onto the loom/battery/cdi with the hugger :D

ducatilover

3rd May 2011, 23:05

haha, riveting stuff was it! Hopefully have it done this weekend, so will let you know if it was a good plan or not. Your ZZR still has the original mudguard anyway though dunnit? I had a bit more pressure to get one on, will still flick onto the exhaust a bit, but not onto the loom/battery/cdi with the hugger :D
I don't think my ZZR has it's hugger? I thought only the 600 had them? I might go and look :yes: The exhaust will look manly and used in no time!

Edit, no hugger, has the big fat ugly rear mud guard though

The Pastor

7th May 2011, 09:40

what did u use to cover the rear tyre?

The Pastor

7th May 2011, 09:42

also there will be a shit load of sanding, and DO NOT do in it a painting booth... dust is the enemy of paint!!!

bogan

7th May 2011, 10:11

Tin foil to cover the tyre, just sanded it off with a flap wheel on the angle grinder. I got some decent bog which makes it way easier to get a smooth surface and reduces sanding, also not caring so much about the bits you don't see reduces a lot too :P Just been sanding in the garden, made a hell of a mess with the flap wheel!

Spearfish

7th May 2011, 10:59

Probably a bit late but we used packing tape over any parts used as a quick and dirty mold.

The binder that holds the fibres together in CSM doesn't dissolve as well with epoxy and leaves a milky finish. Polyester or vinylester is cheaper. CSM and its fibre binder was designed for it.
If your building up layers use CSM, woven, CSM layers they are stronger that two layers of cloth (boat building fail). You can get woven with CSM on one side if your fancy. You can trim the job roughly with a knife before it sets fully.
It stinks like car bog being almost the same stuff. CRC's marine bog is vinylester based and is used for plastic repair.

Epoxy should be used with woven cloth and rolled untill its almost transparent.

Shower bases and baths etc use polyester on the underside of the plastic with some pigment in the last layer. Probably just a 600 gsm and a 450 maybe some core mat on the flats.

bogan

8th May 2011, 13:24

mounted hugger

<img src="http://i285.photobucket.com/albums/ll52/bogan229/P1010616.jpg" width=640 />

<img src="http://i285.photobucket.com/albums/ll52/bogan229/P1010617.jpg" width=640 />

Obviously not up to the standard as production composite stuff, but not bad for a first go I reckon.

ducatilover

8th May 2011, 14:03

That gives me the horn.

Seriously.

bogan

8th May 2011, 15:09

:lol: note to self, no fibreglassing when doug is around

ducatilover

8th May 2011, 15:15

:lol: note to self, no fibreglassing when doug is around

:innocent: It'll be sweet, I'll cut a hole in my pocket...

Spearfish

8th May 2011, 20:32

nice job, so what's next?

bogan

8th May 2011, 20:37

nice job, so what's next?

the cowl, which will be plastic on the outside re-enforced with fibreglass on the inside, hoping for easier sanding and less bog!

Spearfish

9th May 2011, 07:49

A little trick for difficult areas is to mix up a small amount of resin with glue powder, you brush resin over the areas your going to glass then cove a little of the mixed glue in any corners you know the glass will sit up (don't be to neat), place the glass and wet it out (if you don't pre wet it out) like normal. Just roll the glass into the glue mix like its resin.
It stops any voids being left and softens the radius for the next layers.

Urano

9th May 2011, 08:20

bogan

9th May 2011, 09:42

bogan.... congrats!
the hugger is awesome.
incredibly well done considering it's a diy product... :niceone:

now, i'd like to steal the topic to ask if in your opinion it is possible to add a fairing (full or demi) to a street triple....

possible, but you'd need extreme patience (or CNC gear and patience) to get the mold right. Probably better to start with a smaller project to learn the ins and outs of it a bit like I did.

ducatilover

9th May 2011, 21:04

bogan

28th May 2011, 17:38

:love::love::love:

<img src="http://i285.photobucket.com/albums/ll52/bogan229/P1010627.jpg" width=640 />
<img src="http://i285.photobucket.com/albums/ll52/bogan229/P1010629.jpg" width=640 />
<img src="http://i285.photobucket.com/albums/ll52/bogan229/P1010630.jpg" height=480 />

did a rough sand then primer coat today, brought up a lot of surface imperfections to bog up. And will hopefully provide a bit more for the paint to stick to after the final sand, as I doubt it'd stick to the plastic very well without roughing it up a bit. Looks like the exhaust grill needs to go leftwards a few mm, then make brake/indicator lights for it, and also make some covers for the side intake vents. The fit isn't perfect, but am going to recover the seat anyway, and need to trim it up when I do anyway. The seat also pivot at the back and lifts at the front to remove, which is why I couldn't go flush to the cowl there, a bit more seat foam will sort it.

ducatilover

28th May 2011, 18:11

Looks choice bro!

bogan

12th June 2011, 18:01

So to wrap up this thread, I got a pic of the finished bit of cowl fibreglassing (still got to make a brake light and vent fanciness, but that'll go in my other thread).

My review on the process:

Plastic outer shells make it very easy to get the right shape. I used mdf in a cnc mill then shaped with builders bog, but if you don't have a cnc making the mold by hand wouldn't be too hard either.

Was a fairly deep draw for the vacuum molder, so had to trim and bog in places. The machine was also not big enough to do the part in one go, so had 7 bits to glue together.

Sticking the plastic together wasn't too bad, but a lot of sanding and bogging around the joins, if it was doable in one go in the vacuum former this would have been ridiculously easy.

The molded plastic came out with a very smooth finish and really only needed the bits around the mold holes sanded, and a light sand so the paint will stick.

One layer of CSM under the plastic gives plenty of strength, bit of a bastard to get it to all lie flat when the resin was setting, but did a good enough job that I didn't bother with a cloth layer. Will look into vacuum bagging for the next one I think.