Not sure if anyone has mentioned it, but most guitars today are painted with a catalyzed polyurethane, which is kind of like epoxy. Its incredibly chemically resistant, most strippers wont touch the stuff. Mechanical stripping (like a heatgun and scraper, or sandpaper) are usually the best option.

Nitromors is like a non prescription version of a paint stripper lol , i also believe  they altered the formula a good few years ago to remove some nasties and it was neveras good as the original...industrial chemical paint strippers are a different ball game but you wont find them on the shelves in wilkos😂

So. because I don't strip paint often and I'm US based I had to google the brand and a lot of the top results after their own website is forums talking about how Nitromors seems to have had all the teeth taken out of it in the last couple years. A lot of people attribute it to a couple of Health and Safety regs forced them to remove some of the stronger chemicals to stay on shelves.

The good news is a lot of the forums heavily suggested Starchem as a replacement, because apparently otherwise you need to get some kind of registration/license to get full strength stripper, nowadays.

When I used it in the past I covered it very thick and put the body into a black bag overnight. Paint was gone in the morning.

I used this to strip all the paint off an old double decker bus. Idk what type of paint was used on the bus but this stuff got it off with just one application

That was crazy. I can't believe the paint remover didn't do anything. Good job with the heat gun 👍👍👍👍👍

Citrus strip works really well for spray paint I wonder if it would work on poly

The problem is the product work on the paint but not the thic poly finish it got. Heat gun is way more effective or just plain acetone on it.

Tried this stuff years ago on an old encore strat body and it did next to nothing on the poly except give it a bit of a relic job

Those chemicals are usefull only on stains, barnishes and nitro finishes, for poly the heat gun is more effective

Nitro Mors was super simple on the painted neck of my ESP LTD. Saved the day completely. Sanded it a bit first, 2 coats WERE required. The real difficulty lies in having no knowledge what your guitar was painted with, that's why there's no good one-solution-suits-all for this stuff.

You’re not having much luck at the moment mate! Still, it’s made for some good content at least 😂❤

I tried Nitro Mors when i stripped my current bass build. I took like a tiny bit off but the heat gun was FAR superior on getting it off. The "most laquers" just sound like "it can't do fuck all with guitar laquer"

Before you tried the paint remover you should have tried a light sanding all over to the body to take the gloss sheen off it might have gotten into the poly finish a bit better that way

one word of caution (if you don't know already) but nitro might not bond permanently to the base wood - depending on if there was oils of any kind in the previous finish (where poly will stick to slightly gunky oily surface so not as great of care is needed). An alternative for your sealer coat to play it safe would be shellac, then you can shoot nitro safely over that.  I messed up a paint job probably from using tac cloth to get the sanding dust off, where my nitro clear had defects. Had to sand it back and check the old forums for solutions since I couldn't be sure that I had all the tac off. Someone somewhere mentioned shooting shellac then nitro, so kudo credit where credit is due

As the previous comment mentioned, it's partly a demonstation of how insanely tough poly paint is (also why it weathers/relics so poorly) and that NM has been 'watered' down a little. That said, I've used it domestcally in the past, but never tried stripping a guitar with it, so not sure if even the stronger original formula could stripped the poly, though it certainly would've eaten through a nitro finish - so heat gun and elbow grease looks like your best option.

This sort of paint stripper is designed for oil based paint, not acrylic,or polyurethane.Acetone is what is needed.
Try a bit of nail polish remover on a small area😮

From what I understand, Poly clear coat finishes are more akin to rubber than paint. We can surmise this from the fact that polyurethane is the same material that skateboard wheels are made out of. So finishing a guitar with this material (albeit a different formula probably) really gives it that reputation of being near-indestructible! Even if a paint stripper says it can work on poly, I would not trust it unless it explicitly says in big bold print on the front that it also works on epoxy! That material, which I believe is a form of plastic, is equal or superior to poly in terms of durability, so if formulated to remove that substance, it should work for poly as well. Hope this helps at all if you (hopefully) attempt this again for our viewing pleasure...

Jasco has worked for me.

I tried the same thing years ago on a poly finish. I’d used the same paint strippers on cars doing body work to great effect, but it did absolutely nothing on a poly finish. Ended up going with the heat gun.