I'm a GC that learned many years ago NOT to refinish wood floors. Let the pros do it. It seems I've forgotten exactly why but I'm sure my memory will be refreshed soon enough because here I go again.
Refinishing solid maple T&G that has a polyurethane finish. Sanding to bare wood, 36grit, then 60 grit, then 80 grit. Screening with 120 then buffing with maroon pad. Good so far?
Will use one coat Bona Drifast oil sealer, abrade with 120 screen, condition with maroon pad. Then two coats Bona Traffic HD. I'm using oil sealer to get the amber look of oil and not the milky white of waterborne. Have been told that DTS and Amberseal won't do what an oil sealer will as far as amber looks.
The question I have concerns waterpopping. I am a fan and have waterpopped anything that has been sanded and will be stained to raise the grain evenly to accept the stain. I have been told by a flooring rep not to waterpop the floor prior to applying Drifast sealer and not to pop the floor with DTS either. He claims that I will have to work twice as hard to get a waterpopped floor smooth enough for the finish coats. I want a sealed floor that takes the Drifast evenly. Am I risking unevenness in a floor that is not popped?

>>Am I risking unevenness in a floor that is not popped?

No, you're not, because there's no stain involved here, just a sealer. Sealers have no pigment, and won't show uneveness in sanding as much. I'm also a fan of water-popping, but I see no advantage to doing it for a sealer.

As for your sanding grits--you want to go finer than 80. Maple scratches easily, and is very unforgiving on showing edger marks. I'd edge with 120, at least, and some people go to 150 with the edger on maple. The big machine belts for Hummel only go to 120, so that's what we finish with. Then we screen, 120 and 150. Not everybody screens maple, though.

Last--on your dri-fast buffing, don't go 120. That's too aggressive. Use 180, 220, or 240 sanding discs for between-coat abrading.

Thanks for your input. Wish I'd had it before I bought the 120 screens.
What about screening the floor with 120 screen before sealing with Drifast and then use the worn out 120 screens for abrading the sealcoat? What about just using the maroon pads since I won't waterpop?

Bona acknowledged that the instructions still say you can use a worn 120 screen on sealer. But why risk scalping a part of the sealer? That wouldn't have mattered back when oil poly was all anyone used, but it shows under water-based finishes.

The Bona tech I talked to today was saying to use a 220 screen, or the 240 discs--or, just use the maroon pad. It's fine for buffing oil sealer--you're not trying to knock down grain raise; you're just scratching it up for better bonding.

Thanks again for your help. I will take your advice and edge and screen with 120.

I remember that one of the reasons I like waterpopping is that it gives a preview of what stains or sealer will look like and shows defects that can be corrected before applying a finish. Its a whole lot easier to fix a problem before the stain or sealer is applied then after. May waterpop after all.

One last question( I think I already know the answer, so it may be a dumb question). I have an area of high traffic. After the sealer is applied can I do a coat of Traffic HD on the high traffic area, let it cure and then go over the entire floor with two additional coats? Will that first coat of Traffic show differently than the rest of the floor with two additional coats applied over everything?

I'd say it would be OK to do the heavy traffic areas only, and then coat everything else, including that area. It helps if the traffic area is contained, like a kitchen, or a hall. Someone else might have noticed a difference, doing that. What few times I've done it, I've not seen one.

If you're really picky about sanding lines (big machine) and have a maple with knots in it where the lines show the most, you may want to add an extra step of hard plating. Using a double sided sanding disc on the buffer... Perhaps 100 or 120 grit... Unless the 120 belt does well enough for you making the hard plate redundant... Good luck!
Although, you'd be a good fella if you fed a hungry floor pro ... Just sayin