I did a little test on the 3M 07515 Very Fine surface conditioning discs vs the Harbor Freight 61504/99985 Fine discs.
Price-wise the 3M pads run about $1.40/ea. HF run $1.20/ea normally or about $0.96/ea with a 20% off coupon.
General impressions. The 3m pad is thinner, flatter, and does not have any sort of binder visible like the HF disc. The fibers with the 3m disc are finer and there appear to be more of them. Most importantly, the 3M disc is a more pleasant color of blue (they look a bit green due to the lighting in my shop).
First off, the 3m disc. Right two holes were hit with the pad and nothing else. Left two holes were followed up with a couple swipes of the maroon 3m hand pad.
And now the HF pad. This time from left to right there are two untouched holes and then two followed up with the maroon hand pad. The right-most is a comparison with the 3m disc.
They both seem to perform acceptably. The 3m pad seems higher quality and leaves a finer finish though.
As for the amount of material removed, I don't have anything sensitive enough to tell. The ?-2 seconds it takes to deburr the hole removes less than I can measure within the 0.0001" accuracy of my Starrett mic. My understanding is the alclad is ~5% of the nominal thickness, per side, so it's nowhere near breaking through, even on the thin 0.020" material. Notice the cleco left more of mark on the surface than either of the discs did.
Price-wise the 3M pads run about $1.40/ea. HF run $1.20/ea normally or about $0.96/ea with a 20% off coupon.
General impressions. The 3m pad is thinner, flatter, and does not have any sort of binder visible like the HF disc. The fibers with the 3m disc are finer and there appear to be more of them. Most importantly, the 3M disc is a more pleasant color of blue (they look a bit green due to the lighting in my shop).
First off, the 3m disc. Right two holes were hit with the pad and nothing else. Left two holes were followed up with a couple swipes of the maroon 3m hand pad.
And now the HF pad. This time from left to right there are two untouched holes and then two followed up with the maroon hand pad. The right-most is a comparison with the 3m disc.
They both seem to perform acceptably. The 3m pad seems higher quality and leaves a finer finish though.
As for the amount of material removed, I don't have anything sensitive enough to tell. The ?-2 seconds it takes to deburr the hole removes less than I can measure within the 0.0001" accuracy of my Starrett mic. My understanding is the alclad is ~5% of the nominal thickness, per side, so it's nowhere near breaking through, even on the thin 0.020" material. Notice the cleco left more of mark on the surface than either of the discs did.