G10 Fiberglass

[DDW]

For backing plates, the bonding has a very small job to do. Basically level the surface. When using G10 to mount serious hardware, the best method is to bond it on, bevel the edges, and lay some cloth over it overlapping the surfaces. If you are really serious use carbon cloth. This eliminates the free edge effect and mostly eliminates peel problems. I have hardware mounted this way on the sailboat that is taking 7 tons of working load.

 

[Noforad]

Made all my backing blocks. Very tough and is the best choice for me.

 

[Andiamo2018]

Most of the people I've seen working with G10 have WAY more than a covid mask. The dust is apparently really nasty. Some of them had Tyvek suits with sleeves taped to their gloves, full respirator hood and face shield.

It is pretty amazing stuff though.

 

[Redsky49]

G10

G10 is also referred to as Garolite, though that is actually a brand name, sorta like Kleenex.

 

[DDW]

The dust isn't good to breath. It won't hurt your skin, but it will cause you to itch for awhile due to mechanical, not chemical irritation.

 

[Frosty]

Most of the people I've seen working with G10 have WAY more than a covid mask. The dust is apparently really nasty. Some of them had Tyvek suits with sleeves taped to their gloves, full respirator hood and face shield.
.

Since a lot of the stuff used in doing boat work is nasty, I wear a set of PPE much of the time (dependent on task). I do not have supplied air, so I don't do any two-part paint spraying. But I wear what I have for sanding (even plywood/teak/etc.), solvents, paints, colloidal silica, etc.

I use a 3M respirator with the correct cartridges (but not supplied air), hooded Tyvek taped to nitrile gloves, ear muffs when required, and safety glasses or goggles. I don't really want any of that stuff in my lungs, eyes, ears, or soaking into or itching on my skin.

So FRP board is just another of the gang, really. Nowhere near as nasty as atomized paint. The PPE is pretty easy to don as I have it at the ready. Obviously I don't plan that type of job for the heat of the day (but it works out as a plus on chilly mornings).

 

[FF]

If "secondary bonding"and the GRP has cured, as on any purchased product, the recommendation is the surface must be ground so 85% of the surface shows glass fibers.

To avoid the chance of a poorly cleared surface , the navy requires their hulls laid up in a single day.

Polly resin is OK overnight for most folks to continue a layup the next day
ONLY if there has been no wax in the resin to have it cure at the surface.

Any repair or secondary bonding is better done with epoxy , rather than laminating polly resin.

 

[Lostsailor13]

I work as a cnc machinist and every so often we get a job that comes through that is g10 it destroys our end mills and tooling,we uze flood coolant in the milling machines and the fine dust does a number on everything,but it is very durable and lasting material

 

[DDW]

I am very reluctant to machine G10 on any of my machines. When I do, I rig a vacuum nozzle as close as possible to the cutting tool and lay towels on all of the ways that might get dusted. Same thing with hand cutting tools like drill bits and taps - use them for G10 then keep them only for G10 - they will not be much good in metal after that. Even dull tools will still cut the G10. Carbide tools last longer but still dull pretty quickly. Diamond tooling is required if you want them to last.

You can have it waterjet cut and the results are quite good, smooth edge etc. Some waterjet guys won't cut it because of the stink and the dust it puts into the tank. If you do have it waterjet cut and they aren't familiar with the material, you must be careful to either predrill a hole or pierce a hole away from the desire contour as the water jet will blister the material for a diameter about 3x the thickness before it gets through. Once through it makes a nice cut.

 

[sbu22]

With the bucks spent on G10 material, adhesives, tools, and technique, it would seem reasonable to budget a good industrial strength half face respirator with HEPA ("P100") cartridges. And, have it fit tested. They come in different sizes. There are good "field expedient" fit tests you an perform to insure a good fit - google it.

 

[FF]

Long sleeve shirts help but if cutting or grinding using baby powder on exposed skin , and rinsing off first with COLD! water , to close up your skin.

 

[Frosty]

I am very reluctant to machine G10 on any of my machines. ...Diamond tooling is required if you want them to last.

I'm going to guess that the "plain" FRP board (McMaster-Carr, dark green) is easier to cut. Granted, it is not in the same strength category as G10, but depending on what one is using it for, that may not be needed.

For example, I have used the dark green for various bases (seacock backing blocks, a base under deck hardware to give it a "hump" to live on, etc.). I've painted a few of the below-deck backing blocks (where they show), and gelcoated the above decks ones.

IIRC, the dark green is made with polyester resin vs. epoxy. That said, I still use epoxy to bond for the superior chemical bond (so, cured polyester boat, epoxy resin to bond, cured polyester block).

This is not to say anyone should "cheap out" if the project calls for G10. (I have used G10 for a number of things, but had a shop cut it.) And I'm not even sure the dark green FRP cuts easier, but I'm guessing it might because I've been cutting it with my lowly tools for some years and they haven't instantly been compromised. I say "lowly" because it's only drill bits, a "grit" tile blade in a jigsaw, and a router for roundover.

Just something to consider, if you want the properties of a fiberglass backing block but don't need the ultimate strength of the G10. (At least at McMaster the G10 was a sort of snot green last time I bought some; whereas the standard FRP is dark green.)

PS: I was advised not to use the red "fire retardant" FRP board because apparently it doesn't bond as well.

 

[PMF1984]

I think I’m missing something, so please explain.

When using G10 as a backing plate, it’s not going anywhere. It’s being used to spread the load, say for example under a windlass. I don’t understand the need for adhesion to the G10.

Why isn’t it good enough to simply use some type of fill to make sure there are no voids? Such as epoxy with micro balloons, or 4200?

Pardon my ignorance, but I thinking the substitution of G10 in place of the old fashioned oak block here.

John

 

[Alisske]

I think I’m missing something, so please explain.

When using G10 as a backing plate, it’s not going anywhere. It’s being used to spread the load, say for example under a windlass. I don’t understand the need for adhesion to the G10.

Why isn’t it good enough to simply use some type of fill to make sure there are no voids? Such as epoxy with micro balloons, or 4200?

Pardon my ignorance, but I thinking the substitution of G10 in place of the old fashioned oak block here.

John

I dont think your missing a thing! Lol. I use thickened epoxy on a well prepared surface and it becomes “part of the hull”.

Folks may be saying its not necessary. (e.g. - i crimp solder and heat shrink wrap all electrical connections on my boat.). ABYC says crimp and shrink wrap.

 

[DDW]

G10 comes in a variety of shades, dark green to light beige. There is also fiberglass plate and angles, some of which are an extruded slurry of resin and chopped fiberglass, usually green or red. The latter will cut a bit easier (because the glass content is far less) but will still dull tools quickly. G10 is about 40,000 psi strength, the extruded products 15,000 or less - a lot less across the die. Stiffness is also way less.

For a backing plate, almost any filler will do, you just want to spread the load from a few contact points to the whole area. If you are mounting hardware on a G10 plate, or using it for structural loads, you want good adhesion. And in those cases regardless of what you use, a layer or two of cloth over it will improve its peel resistance many fold.