I have FG armor and I heated up some of the parts and bent them into a better shape. I've noticed while I've been working on it that it has slowly gone back to it's original shape.
It has not been subjected to high levels of heat that might explain this, so my question is-

Will I need to secure it with straps or some sort of jig to keep this from happening while it's not being worn?

Anyone else have a problem like this? I assumed that once it cooled down from my iniitial heating/reshaping that it would stay like that.

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"Awww, someone tell me that's a boot!

It's a boot!"

III drops

DONT HEAT FIBERGLASS

i had the same sort of problem when i didy wifes armour. I was thinking of heating and bending it but you need to get it REALLY hot to have any sort of effect and you will more than probably crack it.

Sorry to be such a downer!

_________________
Chaplain Sgt Hohenkerk,
Executive officer - 69th Regt. 1st Batt. Homer’s Heroes

Does not help,
Does not clean,
Will have sex with anything!

After you heated and bent your armor did you plunge it cold water? With plastics and vinyls you need to submerse the part in cold water to "lock" the part in its new shape.

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viewtopic.php?f=4&t=12784
viewtopic.php?f=4&t=12917

You can bend GRP, but you just need to be careful.

Don't heat it up too hot, otherwise you'll cause the strands to delaminate, but it does need to be reasonably warm in order for it to become pliable.

When you have bent it, you ideally need to strap it in place and let it fully cure in it's new shape. This may take a day or so.

It should be fine after that.
Just be careful how you store it, because the weight of the panel can cause it to move out of shape.

_________________
You don't have to be pitilessly sadistic to work here.... But it helps.
http://www.chefs-creations.co.uk/shop/index.php/colonial-marine

http://www.kgbairsoft.com/wordpress

Had the same problem with my old set of MAA armour. It arrived VERY flat so i heated it with a heat gun and bent it into shape as best as i could. It helped a little but it would still try and flatten out over time.

Would some kind of metal bar glued onto the inside help?

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AKA: Simon

Based on the advise above, I would heat it, bend it, quench it in cold water, keep it in a jig to let the new shape cure, then glue a metal bar on the inside to give the new shape some rigidity.

The water 'quench' thing only works with addition thermopolymers like Nylon- they are grabbing hydrogen to saturate the polymer. It's not a quench, just a way of more rapidly acheiving full polymerisation: in injection moulding plants, you'll often see the new batch of nylon parts getting dunked into cold water. If not, they carry on growing for a few hours after moulding- only by fractions of a millimeter for small parts, but this can be enough to give false positives when checking sizes.

GRP is normally made with a thermosetting resin- epoxies etc- which once set, cannot be remoulded by the application of heat.
The temporary deformation reported above is proof of this: heating merely increased the overall pliability breifly. On cooling, the part began to return to shape. The only way to get it to stay 'put' in a modified shape is to constrain it with a metal 'stay' of some type- or if thin enough- laminate the back to the smaller size while constraining the outside shell to the shape required until the new stuff at the back sets the whole thing rigid.

For the armour to be 'remouldable' with heat it'd need to be made of something like kydex or a similar thermoplastic.

_________________
2nd Lt Jon "Jaylo" Lopez
A11/TQ1.0.72144E1
USCM Quality Assurance Division- Aerospace and Space Products- Earth
"Checklists Save Lives- No Service Stations at 30,000ft"

Yes, the firs time I heated it and shaped it, I sprayed the parts with cold water.

But it sounds like the heating/shaping/cooling is temporary. I suppose I could get some metal and attempt to make some sort of "rib" to make it more permanent.
*sigh*

_________________
"Awww, someone tell me that's a boot!

It's a boot!"

III drops

I would suggest the heating, bending, cooling and adding more fiberglass inside to keep its shape method.

Just a further thought for anyone thinking that water 'quenching' can change the shape of fibreglass.

If water exposure causes fibreglass to change shape or set into a new one, where does that leave the millions of fibreglass hulled boats and canoes that sit in water all day?

_________________
2nd Lt Jon "Jaylo" Lopez
A11/TQ1.0.72144E1
USCM Quality Assurance Division- Aerospace and Space Products- Earth
"Checklists Save Lives- No Service Stations at 30,000ft"

I recently used the heat gun and cold water quench on my FG armour, and after reading the postings here I checked to see if my work had been for naught. The changes I made weren't major to begin with, but I did notice a couple of pieces had reverted a little to their former shapes.

The back torso section got the most bending at the sides, from about 46cm (across the widest point between bottom of arm holes) to 42cm, in order to fit into the suitcase I bought to transport it. Surprisingly it still measures 42cm, so apparently it hasn't returned to its original shape in over 2 weeks... I do plan to reinforce the inside with a layer of polyester auto body filler in near future, which will hopefully help retain the changes I made.

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GySgt Gustafson, Dru R.
Callsign: Mud Shark
A06/TQ0.0.32122E1

Rather than using body filler, which doesn't have much in the way of rigidity (and by it's intended usage is supposed to have a bit of flex).
You should try and stick in another layer of glass.

Smelly... but certainly better for it.

To be honest, with all the car bodies, panels, armour parts and other related GRP stuff I've ever had to heat up to move, if you securely fix it in place whilst it re-cures, it will retain 'most' of it's new intended shape.

_________________
You don't have to be pitilessly sadistic to work here.... But it helps.
http://www.chefs-creations.co.uk/shop/index.php/colonial-marine

http://www.kgbairsoft.com/wordpress

If I had the time & means to apply another layer of glass that's probably what I'd do, unfortunately I don't!

I decided to use body filler mainly to reinforce some of the thinner areas inside and around the edges of the torso pieces, in order to add a bit of strength while still retaining some flex. There are areas on the outer surfaces that need filling & resurfacing anyway, so body filler will have to do.

This sounds the most practical solution, at least for my purposes. I'll bind the torso pieces in place after heating, recheck measurements after it cools, then apply the filler and allow it to cure before removing bindings. The alterations are all relatively minor ones in any case, so I expect it'll be sufficient. Thanks for the suggestions!

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GySgt Gustafson, Dru R.
Callsign: Mud Shark
A06/TQ0.0.32122E1

You could use 2-part epoxy adhesive like Araldite too mate. It's way cheaper than the proper resin but is basically the the same thing.

You could bind up your armour then run beads of it diagonally to create ribs.
The stuff sets rock hard, with only a tiny bit of give.

_________________
AKA: Simon

To be honest Dru...

Sticking in another layer of glass is probably no more or less time consuming or costly than adding in a layer of bondo (unless you've got the bondo already that is...).

A cheap glassing kit will only cost you about a tenner...
http://www.halfords.com/webapp/wcs/stor ... yId_165625

(look for the equivalent your side of the pond).

That'll have everything you need to do the job.
Just mix up the goop as you would with Bondo, paint it on, lay on the glass, paint some more goop over the top.
Get the air bubbles out. Let it cure... Job's a good'un.

A brilliant tool for getting the air out and making a nice neat job is a finned roller..
http://www.cfsnet.co.uk/acatalog/CFS_Ca ... s_460.html

You only need a small one.
You can do it with a stiff bristled brush, but these rollers make it a doddle and give a good even finish.

_________________
You don't have to be pitilessly sadistic to work here.... But it helps.
http://www.chefs-creations.co.uk/shop/index.php/colonial-marine

http://www.kgbairsoft.com/wordpress

Those are both extremely tempting suggestions... only a couple of things give me pause though. I'm running out of time and I'm not sure if I'd be able find the equivalent materials over here soon enough. And I already have bought the body filler! However, I'll look into both options and see what I can find.

I've stripped all paint from the inside surfaces and just need to do a bit of sanding here & there. The outside surfaces are mainly where I intended to use the filler, but if I leave the insides as they are, I could probably find what I need when I get back to the states and do it there, when I should have plenty of time to do it properly.

If the shop you posted the link to can ship overseas, then I might just order from them directly, if the postage isn't too high. Otherwise I think I'll wait and see what I can find when I get back to the states. Thanks again for the advice and the links!

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GySgt Gustafson, Dru R.
Callsign: Mud Shark
A06/TQ0.0.32122E1

You'll be able to get GRP in Japan easy enough.

I'm sure someone can point you in the right direction.

Just look for Fibreglass suppliers.

I doubt Halfrauds will be bothered about posting overseas. Their customer service is bad enough for people that live here!

_________________
You don't have to be pitilessly sadistic to work here.... But it helps.
http://www.chefs-creations.co.uk/shop/index.php/colonial-marine

http://www.kgbairsoft.com/wordpress

I've decided to go with your suggestion and add another layer of glass to the insides after heating and binding the pieces in place. There are some very thin areas that need reinforcement and that does sound like the best solution all around.

I found most of what I need online and will finish the job when I'm stateside in a couple of weeks. Not having much luck finding the finned roller yet, however, but I'll keep trying!

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GySgt Gustafson, Dru R.
Callsign: Mud Shark
A06/TQ0.0.32122E1

You can take the head off a hair brush and ram it on a normal paint roller if you can't find the finned roller. Works a treat

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AKA: Simon

Thanks, mate. I'll make a note of that!

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GySgt Gustafson, Dru R.
Callsign: Mud Shark
A06/TQ0.0.32122E1

Yeah, a stiff bristled brush will do a similar job.

It's just much faster and neater with a roller.

But you use what you can find!

_________________
You don't have to be pitilessly sadistic to work here.... But it helps.
http://www.chefs-creations.co.uk/shop/index.php/colonial-marine

http://www.kgbairsoft.com/wordpress