Question:
Joseph,
Just bought three articles off you on sanding, staining and finishing. I’ve got my very first , never done it before job, in my new apartment me and the mrs have just bought. It an old place in Paris from the 1900’s , I assume its parquet is OAK luckily it’s very simple straight floorboards, no 3D stuff. The tough one is will be explaining to the hardware guy all the terminology in French which you have written in your articles… this brings me to my question. (loved your articles by the way, very professional, and even if the french guy says one thing, i’m sticking to your article and that’s that) I found that in your articles there were many floor mecanic terms which I found hard to comprehend. is it possible you could write a short document or glossary on some of the terms you use. like..feathered edge, anti-vibration pulley belts, cinches, chatter marks, long sanding run.. sorry I’m the real layman, I guessed some of them and other I thought were really important to know if I was going to get the job done right. anyway I hope this helps.
Fingers crossed for me, I’m going to have fun trying to explain what a buffer is in french with a special flat aluminum-sanding disk.
I’ll send you before and after photo’s if you like.
Alex
Answer:
Dear Alex
I just got back from my fishing trip, when I saw your email. Thanks for the support and the compliments. As to the flooring terms, sorry about that, but I had to write these articles for pros and semi pros, and I guess it’s a lot easier to use the professional terms for these items. But, for sure we are going to be writing a wood flooring dictionary. And I will probably re-write yet again that floor sanding article to make my words perfectly clear. I do appreciate the feed back.
Anyway here goes. The feathered edge of a floor sanding machines drum is the higher side as it sands the floor. If you take the time to tune up even a rental floor sander, you will see that when you lower the spinning drum to the flat sandpaper held to the floor (as I suggest in the article), that the drum either sands perfectly flat or very very slightly to one side. You will always want to either adjust the machine to sand perfectly flat, or I prefer to have it slightly tilted. But a slightly tilted drum has to travel (as you sand row after row of the parquet) so that the feathered (high side) of the drum sands the floor last. So this dictates the direction of travel when you sand the room. You start on the right side of the room, and work row by row to the left it the drum is sanding high on the right side. Whew !
I don’t think I could explain that any better. But to tell you the truth this is not that important with parquet, as you will be sanding the floor in both directions, so any errors will be somewhat canceled.
The anti-vibration belts are available at http://www.leevalley.com/wood/page.asp?SID=&ccurrency=1&page=30051&category= 1,240,41067
But again Alex these are only needed by the dedicated wood floor professional, and in your case the rental machine may not really benefit from these link belts.
By cinching, I mean, when you attach the sandpaper to the drum, there is a dual roller system inside most drum sanders, that has to be tightened (or cinched) carefully in order not to create a flat spot in the drum. As you can imagine this will create chatter marks. If you are lucky your rental drum sander will have a sleeve of sandpaper that just needs to slip over an expandable drum, but only on the newest machines.
And “chatter marks” are the bane of every floor mechanic. You can commonly see these marks on freshly milled unfinished wood at a lumber store. Particularly on really wide boards. These are seem as regular stripes or waves across the grain of the wood. On wood floors they will also show up when you stain the floor as undulations or waves in the finish. But you are lucky, these marks rarely show up in parquet (the wood grain orients in both directions). You will be screening (or buffing) the floor on the last sanding anyway, these marks will be kept to a minimum.
Oh, and the long and short sanding run, refer to the fact that when you sand a long room, you will be able sand off 2/3 or more of the room by running the machine in (row by row) one direction. To your rear there will be a shorter piece of unsanded floor, that you will get to by turning around, and sanding this section (row by row) until the floor is completely clean. Now with the next pass of finer sandpaper, you need to reverse the short and long sanding sections of floor. Just start from the where you did the short run, but this time do 2/3 of the floor area sanding in this direction.
But again Alex, this is less important with parquet, except on the last two sandpaper passes. Because (as I wrote in the article) the second sanding is done with in the opposite direction in the case of parquet. And then the final two sandpaper grits are done in the original starting direction. So, start North to South with 36 or 40 grit sandpaper. Then use 60 grit to sand East to West, and then finish off with 80 and the 100 grit papers (going again North to South and then South to North, this time reversing the long and short runs. This all keeps the machine marks randomized, and not visible when applying the stain.
And don’t forget to buff the remaining sanding marks out with the large floor maintenance machine. Here is a web site that sells such machines, the Alto Sander 1600 or 1700 is the one you want to use, or whatever you use in France, with 100 grit screens or double sided floor sanding paper. Go to http://regalequipmentonline.com/alto5.htm
The flat aluminum disk is used on such a machine as it stay’s level and does a great job of removing the cross grain scratches of the big drum sander. But you can do it with just the standard rubber and wood or fiber pad provided by most tool rental places. Don’t worry too much about all these details, this is your first job, I took me almost 6 months of full time work to create well surfaced floors, just get to it.
You could always hire a pro to do all the drum sanding and edging and do the final buffing, staining and finishing yourself. I just try to be realistic about the difficult and complicated nature of these jobs in my articles. I don’t sugar coat the truth. Good luck, I hope this all helped. And sure, please send me some before and after pictures, by email if you could. Post it if you have to the address is below.
Any more questions you may have on this subject or clarifications of your original question feel free to write again at no cost. I hope you have enjoyed this personal service, real human responses are the best.
As always your Most humble servant, Joseph, the Wood Floor Doctor.