Composite surface treatment before gluing?

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#1

I am going to be gluing finished carbon composite parts together. The parts were made using a wet layup. The epoxy used was Aeropoxy PR2032. The adhesive I will be using is Aeropoxy ES6271.

I know the mating parts should be abraded or scuffed, but my question is, what other treatment should I perform for maximum bonding strength? There is definitely some powder residue from the sanding that could be removed with a dry cloth, or a damp cloth. I am also wondering if a wipedown with a solvent would help, e.g., acetone. Any ideas would be welcome.

#2

An acetone wipe Always help to remove the last dust, and perhaps some grease or similar. (or at least spread that out, so it does not pose a problem anymore).

When doing a break test, you will notice the bond usually is stronger than the laminate

#3

Ask PTM&W. They’re a good company and will give you correct advice on how to use their products for the best results. Sometimes a solvent wipe is recommended and other times not… ask them for this specific application.

#4

O.K. thanks for the replies.

#5

it’s referred to as bonding, not gluing.

to bond generally, clean the area with acetone, sand with coarse grit, clean again.

here’s a link to hysol’s surface prep guide: https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&ved=0CCcQFjAA&url=http%3A%2F%2Fwww.henkelna.com%2Fus%2Fcontent_data%2F14258_LT4536_TT_Aerospace_Surface_Preparation_Guide.pdf&ei=Wm7sUpKsJMKsyAG51YCYCw&usg=AFQjCNFLmfTPDKn7-RMQqKXHJ4AwS2NOvA&sig2=SLJiR7Pf5N8GM9vWrZJIzg&bvm=bv.60444564,d.aWc

#6

Terminology is important. Thanks.

#7

Another option is Vapormatt. Sort of gritblasting

#8

Admittedly well beyond my scope and budget, but I enjoy learning about all options nonetheless. Thanks.

#9

Oddly, Bell calls for no solvent, but peelply surface, sand with 180grit paper, and cheese cloth wipe until no black shows. Water break test to make sure.
I’d still solvent clean it first if it’s not a new surface, who knows what oils got on it.

#10

When you say water test, do you mean putting a drop of water on and observing if it beads up, where non-beading and wetting of the surface is the desired effect? Intuitively, 180 seems a bit high. I’ve been testing with a coarse sanding sponge which looks to be on the order of 80 or even 60 grit, but I’d go higher if there was a benefit. All surfaces in this project will be new, so no concerns for oils or other contaminants.