Stripping/prepare timber for varnish???

[rando]

I am working on preparing some timber for varnish(Maple) .It had multiple coats of paint that I removed with stripper and sanding.
Ive finally reached the finishing stages but have tiny micro spirals everywhere that just won't sand out.
I started with 80 grade paper , then 120 grade and am now trying to get a good finish to paint,,,,400 grit.
I am going to use low sheen varnish.

My problem is the tiny micro spiral marks that just wont polish out.

No, there is not build up on the sanding pads .
No, Ive checked for a high/hard spot on the sander face .
I am using a quality random orbital!!!
Ive prepared and painted /varnished plenty of timber but never had this happen before, usually enough elbow grease gets a result , but this has me stumped.

What have i done , or, am i doing wrong????:-/ >:( :'(


If I paint a coat of varnish on then light sand and recoat (say 3 coats) will the spiral marks show or are they tooo fine to see through the laquer??:-/

[Roughasguts]

Personally I never use a random orbital sander for that reason.

Belt sander would be my preferance, or hit it with a light plane, to cut past the swirls.

[blaze]

maybe going fine on the grit of the paper, orbital sanders are used in the automotive trade and leave no marks on highly gloss dark colored finishes which IMO is the hardest to prepare
cheers
blaze

[finga]

I'd start with 120 (only if really bad) then 240 then 320 then 400.
Swirls are just left behind from the coarser paper and a too big a difference in the grades.

[BM]

Minor scratches will under normal conditions disappear under a coat of varnish/laquer/clear. Give it a coat. If it doesnt work then its only a bit more sanding!!

I think you'll be fine.

Cheers

[GBC]

Is it a straight grain maple or a birdseye?

[Roughasguts]

Hi Rando, i was just assuming you where using one of those 1/3 sheet rectangle pad sanders.
Cause if you are that is your problem.

[rando]

Roughasguts
No mate not 1/3 sheet ,its a random orbital
GBC straight grain ,,,why??
Finga.
I thought at first it was from going hard at it with the 80 grit and I that i had damaged the surface but it seems the more i sand the worse it gets. I was not getting the finish I was looking for so went back to the 120 (which is pretty fine anyway) after using 400, but could not get the marks to sand out.

[Wahoo]

rando, have you tried to sand the area by hand, (block timber and sandpaper) with the grain?

Daz

[finga]

The 80 grit is pretty severe. It's like dragging the timber across some concrete.
That grit will rip hardwood floors down pretty quick.
IMO there has been some really deep grooves put into the timber with the 80 grit.
The grooves seem to get more severe as the overall finish seems to be getter smoother. It's a bit like seeing a scratch on a car that's 15 years old and lived a hard life in shopping centres and seeing a scratch on a new Porsche. On one it's hardly seen and on the other it'll slap you in the face.

[rando]

Wahoo.
Tried a small area yesterday 120 grit by hand, no block, I made a little headway , it will be a very long job if I have to finish by hand. Tried steel wool too , brought up the grain beautifully , but still left the micromarks.

[rando]

R A G
To many angles for a beltsander.
Finga
I had to go coarse, lots of layers gloss paint, and it was loading the finer paper. Paying for the haste now I think!!!!.