Do I Need to Sand Epoxy Between Coats?

I've been piling layers of epoxy on my walnut Telecaster, trying to get rid of the pores. I have a question.

People have recommended sanding it between coats. Is that really necessary? Here's the reason I ask. If you spray a guitar, the finish will follow the existing surface, so pores will tend to show through successive coats. But if you apply a finish with a squeegee, you're mashing the finish into the pores, so they don't show through very much. A sprayed finish isn't flat to begin with, so it dries with pores showing through, but a squeegee finish is pretty danged flat from the word "go."

I put a few coats on the back of the guitar before thinking about this, and I didn't sand. It looks very flat.

I've been piling layers of epoxy on my walnut Telecaster, trying to get rid of the pores. I have a question.

People have recommended sanding it between coats. Is that really necessary? Here's the reason I ask. If you spray a guitar, the finish will follow the existing surface, so pores will tend to show through successive coats. But if you apply a finish with a squeegee, you're mashing the finish into the pores, so they don't show through very much. A sprayed finish isn't flat to begin with, so it dries with pores showing through, but a squeegee finish is pretty danged flat from the word "go."

I put a few coats on the back of the guitar before thinking about this, and I didn't sand. It looks very flat.

Yes, sand between coats. Thats how you know you are done. If you just keep piling it up, you wont are just making your low spots higher and your high spots even higher.

American walnut should only need 2 coats with a sand in between.

Watch you don't sand too deep and open up pores that weren't exposed to the filler, or you'll be there for ever. And have a really thin guitar.

I don't know if this thing has super-big pores or what, but it's looking like it will take a minimum of 4 coats. I still don't know how to do the sides or corners.

I don't know if this thing has super-big pores or what, but it's looking like it will take a minimum of 4 coats. I still don't know how to do the sides or corners.

What is your application method?

On the front and back, I've been using a squeegee. Some guy named Brock has a Youtube video about it. But his guitars have sides that meet at sharp angles, so he doesn't have to worry about radiused corners.

Man, I just went over the safety info at the West website. This stuff is worse than plutonium. I've never gotten it on myself, but I'm sure I've inhaled some dust while sanding. This may be my last epoxy finish.

Yes epoxy is not exactly healthy to work with specially if sanded before it has completely cured. If you are spreading the epoxy with a squeegee then removing excess, you aren't really leaving enough to buildup. Apply one coat with a brush, spreading it in all directions then let it cure for at least a week before sanding.

You should be wearing a filtered respirator mask when working with epoxy.

Man, I just went over the safety info at the West website. This stuff is worse than plutonium. I've never gotten it on myself, but I'm sure I've inhaled some dust while sanding. This may be my last epoxy finish.

Epoxy is not really different to any other product used to make guitars. You shouldn't be getting any of these chemicals on your skin while they are liquid, in your lungs when they are gasing off or turned to dust.

Wear gloves when applying; wear a carbon filter mask when fumes are noticible; wear a dust mask when sanding. Apply these three rules and you can use all manner of toxic crap!

This is standard practice ... and applies to wood also. Wood dust is bad - and in some cases wood reacts badly with skin.

Here's a bit of MDF's MSDS:

Wood dust has been evaluated by the International Agency for Research on Cancer (IARC) as group 1, carcinogenic to humans. Formaldehyde has been evaluated by the International Agency for Research on Cancer (IARC) as group 1, carcinogenic to humans and by the European Union (EU) as a Category 3 carcinogen (possibly carcinogenic).

Just be smart, not paranoid. Making guitars is toxic only to fools.

+1 to protection while working with wood.

While I was finishing up the body for a bass I started sanding and dust got on my arms. After 10 minutes of sanding my arms got really itchy, and I immediately went inside and washed it off and my arms were red. I hopped in the shower and made sure that every speck of th dust was off of me. It took about a week for the rash to leave. Now I wear gloves and a sweatshirt as well as some sort of mask whenever working with wood or paint.

I have one thing to say to that. MOOPS! MOOPS!