I’m in the middle of an 1100’ job that one of my g.c.’s installed 10” yellow pine plank.

Every time this stuff shows up on a job I get so frustrated over this damn wood. I panic over leaving too heavy scratches from any one of the machines. I’ve mostly had problems with screen marks from using too rough (100 or 120) in the past.

Here’s what we did up to this point:

First cut: 60 (afraid to put a 40 or 50 on it)
Second cut: 100
Screened: 150

Floor got nice and level w/ the 60. Real smooth w/ the 100. And looked mint with the 150 screen ...when it was still raw.

Started applying stain (Ipswich Pine) and BAM! Lines from the drum sander jump out. Not pressure marks ..we were real easy and paid close attention to the feathering. These were like grit lines. Makes me think we didn't screen heavy enough. (Remember I'm afraid to do ANYTHING heavy on this job)

So we stop. Now we try to screen a small test section with a 120 grit. It gets out the drum scratches no problem, stain a small spot, and now there are 120 screen circles! AAAAAHHHHH!!!!

We then hit it the 120 section with a 150 screen again -to get out the 120's, but it doesn’t take them out!! It just clogs the 150 screen as we lean on the buffer trying to get out the damn 120 scratches?

The g.c. trys a freakin palm sander, with a 80 on it, in another area we didn't 120 screen, to try to get out the original drum grit lines. We do a stain test. It works! It doesn’t leave scratches in the process either.

He also says he willing to palm sand the whole floor (1100 sq! how cool is that!) and we are planning to go back and hit it with a 150 grit screen again before staining.

In the future I DO NOT want to palm sand all of these wide plank pine floors.

What the heck does everyone else do to avoid this softwood nightmare?

Sanding pine or fir can be a pain in the ...! If possible, go with a natural finish as pine does not stain well, even with a stain controller. If not, try this, instead of using 100 for your final drum cut, use 120. Lines in floors can be caused by damaging the paper by running over nail heads or bits of dirt so clean your floors well prior to sanding and make sure all nails are set. Instead of using a buffer for screening, which will produce some swirl, use a orbital sander (not a palm sander) but similar concept.
http://www.hardwood-floor-sanders.com/o ... anders.asp
This sander does a great job at sanding without the swirl. You can use sheet paper, screens, marroon pad, etc. There are other sanders that work in a similar fashion. http://www.hardwood-floor-sanders.com/discsanders.asp If you don't want to buy, then rent for the time you need it. That would be cheaper than redoing the work. Good Luck!

Thanks for the advice.

I had considered an renting an orbital but the gc was takin care of business for me.

I also always perceived that these machines were a homeowner's rental specialty and that they didn't really work too good. Kinda like a 110v drum.

And the 120 drum sounds like the thing to do. I believe we left 100 grit marks and the 150 screen will most likely get out the 120's

For the record:

-home owner wouldn't budge in going with a natural -or lighter stain
-we swept carefully between cuts
-checked for paper dings & low spots quite often
-floor was face nailed and set about 3/16" deep

THREE QUESTIONS PLEASE:

1) Do you suggest cutting 60-120 or do a 60-100-120?

2) What grit on the orbital to get out drum grit ?

3) And what about the 150 screen after the orbital?

Contrary to most advise, you can skip two grits IF you walk a little slower and keep a medium pressure on your drum head. What you are doing is sanding out the previous grit's sanding marks. So you need to let your machine do that. If you walk too fast, cut too wide a path, or use too light of pressure, you will leave sanding marks from the previous grit. So, answer to question #1 is 60 then 120 if you follow the above guidelines. Note: there are some pines with a heavy sap content that will clog and burn when sanding. I haven't noticed this in Southern Yellow Pine.
#2) You can use screens on the orbital. For Pine. I'd use 120.
The orbital with 120 screen will give a fine finish. I can't see the need to screen with a buffer and 150.

If I were sanding the floor, I'd drum with 60, edge with 100, drum with 120, screen with 120 using the Orbtal. Of course you will need to deal with the corners and edges by hand.

I was having similar issues in red fir and Gary seems to have told you everything that I figured out the hard way. I totally agree with him in all that was said. I vaccuumed between each sanding on an old refinish first with 16 (tons of old wax and mastic from linoleum) 50, 80, and fined with 120, walked just alittle slower than usual on a fine cut, and moved over about 3 inches with each pass .. violla! No machine grainy marks.
Regards,
William
PS I will e-mail the before and after pics to you if you'd like to see em[/img]