Heavy cut compound discussion / help

[Farmall-luvr]

I use the 3401 with M101 and just do as many passes as it takes. I`d probably ly at least consider resanding 2K with 3-4K, I don`t like working 2K scratches.

I have an easier time removing 1500 grit scratches than 2k unless it`s a small spot.

I did the hood on a black 2018 Equinox a couple weeks ago that our body shop pushed out too quickly and had a ton of solvent pop.

I sanded the hood with 1500 by hand and then 3000 trizact with the da and buffed it out with a wooly and 3 m perfect it steps 1,2 and 3,,step 2 with a black foam pad and step 3 with a light blue pad,,all 3m brand.

[Accumulator]

Farmall-luvr- Ah, Perfect It! Heh heh, didn`t think anybody remembered that line I liked the PI-III, but none of their other variations.

I`m confused! Why would it be easier to remove 1500 than 2K?!? The scratches are deeper, so you have to remove more to make it level, so you`re doing more work, and to *me* that makes it harder. Gee, I haven`t tried to take out 1500 since...man I don`t know!...maybe the `70s, back before we had decent high-grit papers (let alone sanding disks).

I note that you follow 1500 with 3K, which seems contradictory to the above...I`m sure not trying to argue or anything like that, but I am confused

EDIT: Oh, and Welcome to Autopia! Don`t think we`ve shared a thread before..

[Farmall-luvr]

I use the Perfect II ,,I use 2000 too,, but I`d rather sand less and buff more and it takes me longer to sand some imperfections out like runs and dirt with 2000 than 1500 and I hate using 1000 or even 1200.

as for the wet sanding solvent pop with 1500 by hand and moving up to 3000 trizact DA that was suggested by one of our body guys ( the one I don`t have to fix stuff behind) it worked,,normally I would go 2000 and then the trizact ,,plenty of clear to do it.

plus the owner the dealership is a tightwad and won`t buy trizact,,we sneak it in

[dcjredline]

When these compounds all claim 1200 grit capability I figured I could breeze through 3k sanding marks. Thats my main disappointment
.

[Farmall-luvr]

somtimes I find that I move too fast for the compound to be effective or use not enough product,,,if I gotta go over it a couple times I`m ok with that,I get less arm pain buffing than sanding

[Accumulator]

When these compounds all claim 1200 grit capability I figured I could breeze through 3k sanding marks. Thats my main disappointment.

Heh heh...[INSERT total disbelief regarding those "what grit?" claims...HERE]

Farmall-luvr- I suspect I misread your earlier post...

Yeah, some stuff just calls for a more aggressive grit and Trizact is *MUCH* better stuff these days compared to how it used to be.

In some cases, I find that wetsanding ends up removing *less* paint/clear than compounding because with the right block/etc. you primarily just cut the high points whereas the pads used in compounding are more likely to conform to the texture of the paint and remove from the "low spots" too.

If you`ve never tried them, some of the newer compounds are in a whole `nother league compared to the 3M. I`m no big Meguiar`s fan, but stuff like M101 prompted me to forget about stuff like the 3M.

Not that I give real thought to such stuff these days And solvent-pop is a nasty FUBAR situation IMO..that was a huge part of why I sold my last M3, just wasn`t gonna deal with it (too bad I didn`t spot it pre-purchase ).

[Stokdgs]

I remember 3M Perfect-It compounds from the 70`s... Wow, been around almost 50 years...
Every body shop I have either worked in or walked into and looked around all use the same 3M products... Its part of the culture...

Agree with my other brother, Accumulator - there are much better products out there that work better, faster, and no dusting if moisture is managed a bit..

And since all the automotive paint supply stores still carry 3M compound, etc., products, they are never going to go away..

Regarding solvent pop - I never had anything like that happen to me or the Painters I worked with.. Worse thing that ever happened was fisheyes from not completely cleaning the surfaces before laying down the paint..

Sounds like user error causes this, no ??
Dan F

[Accumulator]

Regarding solvent pop - I never had anything like that happen to me or the Painters I worked with.. Worse thing that ever happened was fisheyes from not completely cleaning the surfaces before laying down the paint..

Sounds like user error causes this, no ??

Yep, user-error on the part of the painter. On my M3 it was a case of "oh [crap] this is getting worse instead of better", every bit of clear I removed exposed more trouble, just no way to correct it without uncovering more of the solvent pop so it was a no-win for me as I wasn`t gonna repaint it.

Oh, and I still use 3M PI-III Machine Glaze 05937 now and then. A really-not-bad light polish, last time it was on smooth black exterior plastic, perfect product for that particular material. Eh, PI-III abrasives and the pre-VOC Showcar Paste Wax are about the only 3M stuff I ever liked. PI-II was unsafe without a respirator, PI-3K never worked well for me except with a rotary (and I didn`t like it then either). Their papers were all over the map until the Corporate changes involving Meguiar`s a few years back, I use used other brands like Mirka.