I recently tried out 3M Perfect-It III Fine Cut and the Imperial Machine glaze (though Im led to believe that the range available in the US is different from the UK...) and I have to say I was impressed with them. In my eyes, not quite as good as Menzerna that is my staple polishes, but still very good... here's my thoughts that I posted on a UK forum:
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Many thanks to Breezy on the forum for sending me samples of 3M Perfect-It III Fine Cut Compound and 3M Imperial Machine Glaze to try out. I have spent a few happy hours this afternoon trying these two products out on both rotary and PC with various application techniques and I have to say I am impressed with them overall.
Rotary
First of all, the panel was given its traditional (for my product experiments) wire wool wash!:
In order to remove these, I went for the Perfect-It III Fine Cut Compound applied by rotary using a Meguiars W8006 Polishing pad. The compound is a thick white consistency, reminds me quite a lot of Menz Intensive Polish in this respect.
One thing that became clear from the outset using this product was the time taken to break down - this product has a long work time

. Inital playing around, using speeds up to 1500rpm (spread at 600, two passes at 1200, several at 1500, finish at 900) removed the defects satisfactorily, however if the polish was not thoroughly worked then (as with all polishes), faint hologramming was resulting:
Playing around with this compound though, I found that I actually got better defect removal from it, and broke it down more effectively by raising the speed up to 2000rpm. They way I settled on, well the way that worked best for me personally, was spread at 600rpm, a couple of passes at 1200rpm and then seven or eight passes at 2000rpm and then finish at 1200rpm for two passes, with the following result:
The finish appeared hologram free, defects effectively removed. The product seemed to have a cut quite similar to Megs #83 and Intensive Polish, or at least it felt like it did. The finish for me was good, not quite as clear as that left my Menz IP PO85RD3.01, or the clarity of the Menz Final Finishes but still a good finish...
It doesn't stop there though, as to further refine and add wettness to the finish, there is the Imperial Machine Glaze. This I applied using a Meguiars W9006 Finishing Pad. The product was a hot chocolate colour, and quite thin consistency and reminded me a lot of Meguiars #3. I applied it in a similar way too and it worked effectively - spread at 600rpm, couple of passes at 900rpm, and five or six passes at 1200-1500rpm, finish with a couple at 900rpm. The results:
This increased the clarity of the finish under the Brinkmann, and coupled with the Fine Cut compound above these two products would make an effective polishing pair for work by rotary IMHO. The key to them was to ensrure they are thoroughly broken down and this takes quite a while, they do have quite a long play time on them. The wettness of the finish was also good:
For me, the finish was as deep or glossy as one finished with Meguiars #7, or as crystal clear as one finished with Menzerna PO85RD Final Finish, but the finish was still very good. In fact, I am impressed with these products.
Porter Cable
Right, out with the DA now, and wash the panel again with wire wool:
Again, a Meguiars W8006 Polishing pad was used by PC. I spread the Fine Cut Compound on speed 3, then made three passes at speed 5 and followed with eight or nine passes at speed 6. This polish did take a long time to break down and for the residue to go clear on the PC, very similar to the breaking down of IP3.01. The residue wipe away cleanly but I got a little surprise at this stage - a hologram??:
Looking more closely, this appeared to be micromarring, quite similar to what you wouuld see from a product like Menzerna Power Gloss:
Now, after playing aorund in the summer, I was finding that by PC a great many polishes leave micromarring to an extent and only the rotary was capable of achieving a finish approaching crystal clarity... Again here, I was noticing this kind of very light marring from the Fine Cut, using multiple methods of application (the above got the best results).
The majority of the defects were cleared, only deeper ones remained, though by PC the micromarring was noticeable: definitely more noticeable than Intensive Polish for example. However, this is a compound with what seems to be a fairly strong cut judging by the defect removal achieved so a degree of micromarring was to be expected and as discussed previously, very very light micromarring appears to be par for the course when using a free rotation DA like the Porter Cable.
So, onto the Imperial Glaze to refine the finish. Spread on speed 3, and then about ten passes on speed 5, and then the residue was removed with a mf towel. The results:
The finish was improved on the above, but close inspection reveaed that still a small degree of micromarring was remaining - this would likely be un-noticeable in the majority of paints, especially metallics but on solid dark colours this would have to be a consideration. Take nothing away from the products here though, defects were very effectively removed and as the pic below shows, a nice deep and glossy shine was achieved:
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Summary
After initial playing around with this pair of 3M products, I am impressed with them. The products have a good play time to them, break down effectively (especially on the rotary) and are very effective defect removers. The quality of the finish is good, they are easy to use and residues wipe away with ease. For me, these products are most certainly competitive up against he likes of Menzerna and Meguiars, though I still personally lean towards Menzerna owing to the greater clarity I can personally achieve in the finish from the products. Certainly I would not overlook the 3M gear tho.
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