G10 Backing Plate

[DCatSea]

One of my many 2021 layup jobs is to replace backing plates on handrails and deck fittings. G10 is one of the recommended materials for this, so:
A) Has anyone used it, and know of any issues with it?
B) Has anyone other recommendations for backing plates?
As always, I'm looking for something that is workable with "usual" tools, and that won't require a second mortgage to implement.

Thanks

[jleonard]

I don’t know what G10 is but I always like to use plywood for backing plates. Easy to shape to fit will deform a little bit to a not flat contour and has ability to give a little under strain.

[Ben423]

G10 is made of fiberglass cloth and epoxy resin that is cured at high temperature and pressure in a platen press. It is heavier than aluminum and very strong material that is usually cut and machined with carbide tools. I have used it for backing plates and other applications often in the past and it is superior to wood or metal. It does not rot or corrode and is impervious to water and most chemicals. It can be painted but doesn't need to be. It is easily available but is expensive compared to wood or aluminum.

[Pitou]

I've only used the ready made G10 backing plates made by Groco for utilizing with their thru hulls and the stuff is STRONG! I think that your plan is a great one.

Here are a couple of photos from last spring's holding tank discharge thruhull refit -

20200525_165642.jpg

20200525_172457.jpg

Thruhull to G10 Block.jpg

[JackK]

Sorry I don't check in as often as I used to.

G-10 also called FR4 is as described by others a fiberglass epoxy material. It is used in most circuit boards. It is water impermeable making it a good choice for backing material. It is extremely strong and takes well to tapping. In my business we machine sheets of G-10 for the manufacture of test equipment for printed circuit boards and assemblies. You want to use carbide cutting tools as it is quite abrasive. It is available in sheets of varying sizes. For the DIY side, I believe McMaster Carr carries it in different thicknesses.

Jack

[SkipD]

G10 is great for backing plates. No rot, great strength, easy to work with.