Machining marks have appeared after staining?

[mctubster]

Hi all,

I have been working on a desk top for a while.

I am using 30mm A Grade furniture ply.

I have sealed x1 and stained x2 ...

Some kind of machined mark on 50% of the surface has become visible running against the grain once I applied the first stain coat. I tried a second coat (planned to go darker), but is still obvious and bugging me. My wife thinks it is fine but I know it will drive me nuts!

What now? I have only been sanding by hand so far with the grain (across the machine marks which have now appeared after the staining).

I have a random orbit and my first instinct was to attack with this 300-400 grit (because it's ply I have to be careful, already popped my sanding through ply cherry)

Thanks for any ideas
Steve

[soundman]

Well of course they have.

sanding errors will frequently show up on a later stage of finish.


there is no solution but to go back and correct the error at the stage it occured.

NOW

If you have a ROS, particularly a larger 6 inch one with variable speed, use the damn thing.

You simply can not comptete with a ROS sanding by hand.

but you must be consistent even and light handed.

as for 400 grit.

what top coat are you using? before most top coats there is very little point going much past 180 particularly on a ROS..240 tops.

save the 320-400 for between coats.

Now have you sanded thru ply on this job or is this a past sin?

If it was me presented with a sheet of ply I would be putting 180 (120 if it was a B or C surface) on the ROS dropping the speed low and working with long slow strokes the whole length and then the whole width of the job.

OH BTW you are using a VAC with your ROS.

cheers

[mctubster]

Hey Soundman, thanks for your reply. I have a 5" ROS with bag.

Sounds like I will have to take it back a bit ...

Yeah sanded through ply on a previous job. Good learning though :)

Cheers

[soundman]

do ya self a very big favor and get that machine hooked up to a a vac.

It will improve the performance of the machine, the cleanliness of the job and you comfort with the machine.

cheers

[mctubster]

Wanted to follow up with what I have done so far.

I sanded back to the bare ply using my 5" ROS, which I attached a vacuum clear to.

I used 120 grit and then finished with 180 before sealing and re-staining and all of the machine patterns have been removed.

Cheers

[soundman]

Don't ya love it when a plan comes together.:2tsup:

Isn't that ROS a happier thing with the vac attached?:D

cheers