one off fenders cast from originals (fiberglass)

[roonie]

i have a new set of fenders...i was thinking why not lay up some fiberglass on top the new fenders. They wouldnt have the flex like originals but would they crack and break on the forest trails with branches hitting them etc? Is there a flex agent i could mix into the fiberglass...input anyone?

[BOB MARLIN]

I have a set of fiberglass fenders on one of my atc 70's. They look great but don't handle much abuse.

[roonie]

ok..good to know...i probably wont go that route then

i thought there was some type of plastic that once heated would form to whatever shape a person wanted?

[Dirtcrasher]

Mine lasted 3 rides.

My buddy got a set from the last batch, his broke too...

Honestly, when guys are making them to sell, they aren't going to make them strong due to excess materials/labor and you'd never come buy to make more, like pharma's do with cancer drugs.

If I were a fiberglass guy, I'd just add layers after layers, switching the grain etc etc and I'm sure they'd last allot longer than ones people sell us to make money...

[barnett468]

i thought there was some type of plastic that once heated would form to whatever shape a person wanted?

There most certainly is, and it has been around since at least the late 1950's and is what a lot of car and truck interior parts were, and still are made out of. I had the toy below in the mid 60's that would do exactly what you are asking about. One of the stronger types of thermally moldable material is called SMC (for sheet molded compound) which is fiberglass reinforced polyester, and is what we used at Kawasaki to make the jet ski body parts out of, but you asked about hand laid fiberglass and I'm guessing something that one could easily use at home.

https://en.wikipedia.org/wiki/Sheet_moulding_compound


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[roonie]

yes...i have a brand new set of fenders ive had for years and wanted to use the shape of them to mold another set from. I just recall , somewhere , that there was a plastic sheet that when heated would go all floppy and fall into a form





There most certainly is, and it has been around since at least the late 1950's and is what a lot of car and truck interior parts were, and still are made out of. I had the toy below in the mid 60's that would do exactly what you are asking about. One of the stronger types of thermally moldable material is called SMC (for sheet molded compound) which is fiberglass reinforced polyester, and is what we used at Kawasaki to make the jet ski body parts out of, but you asked about hand laid fiberglass and I'm guessing something that one could easily use at home.

https://en.wikipedia.org/wiki/Sheet_moulding_compound


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[ps2fixer]

My 1976 ATC90 had fiberglass fenders (factory I think), they were cracked in the corners by the seat, but otherwise looked great. It seems good sets can be made, but like it's said above, its going to take multi layers.

Might not be the best example, but a lot of truck toppers are made of fiberglass, they are heavy but hold up well. Toyota even made one for their 86-89 4runner that's more of a SUV body, but the rear section had a removable topper. I'm not 100% sure if it's made of fiberglass, but it's just as heavy lol.

The melted plastic sheet process I'm pretty sure is what Maier uses (vacuum molded). I wanted to poke around this a bit, but the larger parts would be quite a challenge to get a large enough oven for the plastic sheet and I have a lack of room for the molds. Maybe someday though, or someone else could attempt it =).

[Shep1970]

Just messin’ around, I only had 3-chip clips and my younger son to hold it in a couple spots. A red Meier (sp) 200x front fender is underneath the maybe 4mm 2-part mix. Hmm not sure how to get it out now ;) again I’m just playing, and the Black is difficult to take pics of. Maybe 6 guys and a vacume bag could do it but who knows.... alright I’m back to lurking...

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About a half hour set time so about 15mins into it you’ve got 5-mins of forming. I’m not recommending this I just thought it was interesting. I’m just happy it didn’t become a permanent part of my countertop.

Shep

[roonie]

did you use a release agent?





Just messin’ around, I only had 3-chip clips and my younger son to hold it in a couple spots. A red Meier (sp) 200x front fender is underneath the maybe 4mm 2-part mix. Hmm not sure how to get it out now ;) again I’m just playing, and the Black is difficult to take pics of. Maybe 6 guys and a vacume bag could do it but who knows.... alright I’m back to lurking...

258439 258440 258441 258442

About a half hour set time so about 15mins into it you’ve got 5-mins of forming. I’m not recommending this I just thought it was interesting. I’m just happy it didn’t become a permanent part of my countertop.

Shep

[Shep1970]

did you use a release agent?

Yes, I sprayed everything. This fender with a little trimming around the edges I maybe tempted to use someday. It’s very glossy too, the underside not so pretty though. 258443 258444
The plastic had the consistency of a fruit roll up when I formed it if that makes sense.
Shep

[barnett468]

Just messin’ around, I only had 3-chip clips and my younger son to hold it in a couple spots. A red Meier (sp) 200x front fender is underneath the maybe 4mm 2-part mix. Hmm not sure how to get it out now ;) again I’m just playing, and the Black is difficult to take pics of. Maybe 6 guys and a vacume bag could do it but who knows.... alright I’m back to lurking...

258439 258440 258441 258442

About a half hour set time so about 15mins into it you’ve got 5-mins of forming. I’m not recommending this I just thought it was interesting. I’m just happy it didn’t become a permanent part of my countertop.

Shep

What plastic did you use exactly and what was the process?

[Shep1970]

What plastic did you use exactly and what was the process?
This link will show you what I used (bjb tc-808 jet black) process- just formed it over an existing fender while pliable. Sets up rather quickly. https://bjbenterprises.com/index.php/tc-808-jet-black-a-b/

Shep

Really just mixed a+b dumped it on the counter let it run flat/level I’m guessing 3-4mm thick, let it set until not tacky then just picked up and layed on the fender molding/pressing while it set up stiff.

[ps2fixer]

Looks like it came out pretty nice, who cares about the bottom side. Pretty neat idea, is that the normal usage for that plastic, or did you come up with that on your own?

[roonie]

Thats exactly the process im talkin about....now tell me, how tough a beatin will they take ...cause i hunt hard with my machine in the thick forests up here

[Shep1970]

Looks like it came out pretty nice, who cares about the bottom side. Pretty neat idea, is that the normal usage for that plastic, or did you come up with that on your own?

Read roonies post yesterday and you guys were talking about needing heat for forming sheet plastic and this is what I came up with. Oh yes there is heat (chemical reaction) but just warm. I don’t “think” it would hold up to much abuse though. A front fender it’d probably be fine but rears I highly doubt it, it would probably be a bad idea. May work great for like side panels and things. I need a dummy fuel tank and may go this route. Or like a two-part mold for seat foams:naughty:

Shep

[ps2fixer]

Ironically, I was poking around some ideas for CADing up seat pans, just need to make them, send to you for the foam, and cover to resell ready to use seats =).




If you're handy with metal, a metal fender would hold up the best, be kind of heavy, but is the best guard against trees and brush. Reminds me of my uncle's TRX125, we had to make new trails on the power line road, so that little machine was used to run over ~10-12ft tall brush. It was so thick had to go up it till the back tires came off the ground, then back up and hit it again. I've done similar with my ATC200ES, but the brush kept pushing up on the shifter and making it clutch. A small pipe bumper went a LONG ways on that TRX125, and later the 350 warrior I rode the snot out of.

Fair warning, wrecking at speed with metal fenders likely would cause more damage to the rider, kind of a trade off I guess. It also would probably look like crap, but never know.

[RubberSalt]

You can make a large vacuum form out of plywood and perforated board/plywood. Connect several shop vacs to quickly pull a vacuum. Youtube it.

[roonie]

Shep....im interested to know your thoughts on why you dont think this process and plastic would take much abuse..are they brittle? Does it flex?





Read roonies post yesterday and you guys were talking about needing heat for forming sheet plastic and this is what I came up with. Oh yes there is heat (chemical reaction) but just warm. I don’t “think” it would hold up to much abuse though. A front fender it’d probably be fine but rears I highly doubt it, it would probably be a bad idea. May work great for like side panels and things. I need a dummy fuel tank and may go this route. Or like a two-part mold for seat foams:naughty:

Shep

[Shep1970]

Shep....im interested to know your thoughts on why you dont think this process and plastic would take much abuse..are they brittle? Does it flex?

Theres no real short answer to that, been trying to think of something to compare it to. On a shore scale this is a 78d but there are softer more flexible plastics available too. I guess this plastic is similar to a auto interior plastic, firm and has some flex but bend it too far and snap! The key dashes I’m doing are made from this 78d, I bet I could stand on one but if I jumped on it it’d break apart not nessasary shatter into a million pieces though.
I don’t know what to tell ya. Careful messing with this plastic hobby though it’s VERY addicting......

Shep

[roonie]

ive watched a couple vids on youtube where they heated the blue rain barels and made other parts from the melted plastic...surely that blue plastic from a rain barrel would flex nicely? The plastic is HDPE. Shep...are you using HDPE plastic? Surely we can make a couple side covers for the honda big red 250 es that are a pocket full of $$$ at another plastic maker company

[Shep1970]

ive watched a couple vids on youtube where they heated the blue rain barels and made other parts from the melted plastic...surely that blue plastic from a rain barrel would flex nicely? The plastic is HDPE. Shep...are you using HDPE plastic? Surely we can make a couple side covers for the honda big red 250 es that are a pocket full of $$$ at another plastic maker company
Nope it’s not hdpe. I play with polyurethanes/urethane/silicone/epoxies.
To busy to even think about doing side covers honestly. Life’s real busy at the moment:beer

Shep

[ps2fixer]

One thing to remember with molded plastic, the mold cost is quite a bit and it's only good for so many runs. Vacuum molding I'm pretty sure it lasts longer, but the big red side covers couldn't be made that way because of the pins that stick out to hold it on the machine.

Probably the best option is to pay the big big $$$$ and get an injection mode made (like $20-80k cost), then you can produce 1000s of units for cents each, just the mold cost is what kills the costs and probably not enough people that want/need the part to offset the huge up front cost/risk. You could probably have it made a fair bit cheaper in China, but good luck with quality control.