Flox between layers of glass cloth

[rv9builder]

The Aircraft Spruce catalog says "NEVER use micro between glass layers." Is it acceptable to use flox or some other type of filler between glass layers?

Thank you,

[mdredmond]

How much build-up do you need?

You should alternate layers of cloth and mat. A bunch of mat or chopped or milled glass can be used as a structural filler. Not sure if you can use flox between layers of cloth, but seems to me it would not be nearly as strong as mat or chopped glass.

[gpiney]

Originally Posted by rv9builder

The Aircraft Spruce catalog says "NEVER use micro between glass layers." Is it acceptable to use flox or some other type of filler between glass layers?

Thank you,

The basic answer is NO! The strength of multiple layers of fiberglass comes from them being together with no voids or other material between them. A composite sandwich (glass-foam-glass) can also be made very strong.
Flox mixture is Very Heavy. Sorta defeats the purpose. Flox is generally used where a hard surface or point is needed.

If you could describe your problem, a better solution may be given.

[f1rocket]

Originally Posted by rv9builder

The Aircraft Spruce catalog says "NEVER use micro between glass layers." Is it acceptable to use flox or some other type of filler between glass layers?

Thank you,

You should never use micro between layers, but flox is sometimes acceptable. There are usually other techniques that are stronger and lighter than flox to build up an area that should be explored first. Describe your problem in more detail and pehaps we can assist you with a solution.

[David-aviator]

Originally Posted by rv9builder

The Aircraft Spruce catalog says "NEVER use micro between glass layers." Is it acceptable to use flox or some other type of filler between glass layers?

Thank you,

Having been somewhat educated in the EZ world, the answer is NO.
I do not recall ever using a filler between layers of glass.

dd

[Finley Atherton]

The only time that flox is "sort of" used between glass layers that I am aware of is when two lay-ups of glass meet to form a corner over a foam core. In this situation the corner of the foam is removed after one of the sides has been layed-up and allowed to cure. The resulting void is filled with flox and the other side is then glassed over the wet flox. So you end up with two glass lay-ups joined by flox at the corner.

Fin
9A Australia

[rv9builder]

Originally Posted by f1rocket

You should never use micro between layers, but flox is sometimes acceptable. There are usually other techniques that are stronger and lighter than flox to build up an area that should be explored first. Describe your problem in more detail and pehaps we can assist you with a solution.

Thanks for everyone's help. I'm working on a fiberglass rear skirt for my 9A slider. There is one area where I think I can get a smoother shape if I add some filler. I was going to add some filler, and then do another glass layup over the original layups and the filler. Based on what you guys are telling me, it sounds like I should do all of my glass layups first, and then put the filler on top, instead of sandwiching filler between the different layers of glass.

[gpiney]

You got it.

[f1rocket]

Originally Posted by Finley Atherton

The only time that flox is "sort of" used between glass layers that I am aware of is when two lay-ups of glass meet to form a corner over a foam core. In this situation the corner of the foam is removed after one of the sides has been layed-up and allowed to cure. The resulting void is filled with flox and the other side is then glassed over the wet flox. So you end up with two glass lay-ups joined by flox at the corner.

Fin
9A Australia

That's the primary one, but if you lay a bunch of plies to make a hard point, and you need to smooth the transition around the build-up, you can lay in some flox in order to avoid any voids in the layup. Generally, the use of flox between layers is avoided because of weight, not strength. It is extremely hard and strong, as you probably know, but weighs quite a bit. Glass cloth with grab flox quite readily and not let go. Not so with with micro, which will stick to the cloth, but has a very, very low shear value and the glass will easily seperate from the micro with just a minimal shear load.

[DanH]

He's talking about a canopy skirt, not a structural part. No problem with flox core between cloth layers in that application.

Dan Horton