Brilliant sandpaper - clogging?

[Greg_R]

I have been using 320 and 400 grit Brilliant sandpaper to prepare a finish for buffing with Platin.  I'm finishing the project with Waterlox and it is made from walnut.  I have been getting a lot of dark specs on the paper.  This is not dust coloring the paper... it is compacted blobs of dust and finish.  I am using an ETS150/3 and my CT22 is set to full power.

1) Is the paper actually clogging or is this normal behavior (easy to see with dark wood / white paper)?
2) If it's clogging, am I doing something wrong (sanding before the finish fully cures, etc.)?
3) I'm using the correct paper for this, right?

Thanks!

 

[Per Swenson]

Hi Greg,

Turn the suction down on the Vac until the sander just releases from the surface.

Floats is the word we are looking for here.

Do not put downward pressure on the sander, just let the sander do the job.

Keep it moving.

And yes, make sure your finish is fully cured.

And I will say this again.

Results will vary depending on finish used, relative humidity during application

and the finishers patience in getting the job done. ;D

Per

 

[nickao]

Per is correct of course.

I addition you should get nothing but a powdery off white dust when sanding the finish in prepartion for buffing. If you are getting blobs after Per's suggestions than you need to try a different sandpaper all together.

You may be sanding to much, heating up the finish. You only need a really light sanding for what you are doing.

Nickao

 

[Greg_R]

Thanks guys.  I think my problem may be that the finish is not fully hardened (gave it 2-3 days).  The sander is floating, I'm using a very light hand and moving the sander 1"-2" per second.

 

[tvgordon]

I'm not sure, but running the sander at a slow speed setting might help also.  I've not tried to power sand a finish yet, I still sand finishes by hand.  But even when hand sanding, I'll get globs of finish if it isn't fully dried or if I hit a run.

Tom.

 

[John Langevin]

Did you stain the wood prior to applying the Waterlox? Every clear finish that I have sanded produces white dust, if you are getting brown 'globs' I wonder if you are pulling up the stain with the finish. Aside from the brown stuff on the paper, how does the finish on the wood itself look? It seems possible that the stain and/or the finish are not completely cured. Per can you lend your expertise here? Inquiring minds need to know.

 

[Greg_R]

No stain, just Waterlox "sealer & topcote" (for a satin finish).  The dry time has always been at least 24 hours and as much as 4-5 days in a unheated shop.  I applied the finish by wiping it on with a clean rag.  The finish is definitely dry to the touch but I don't know how to tell if it's fully cured or not.  The finish looks and feels great (sand up through 500 grit, then apply wax with hand + vlies / rotex & then buff out)... I just get the specs/blobs all over the paper when doing the 320 and 400 grit sanding.  I have a suspicion that the finish was not completely cured (not warm enough in the shop).  I have tried sanding bare walnut with these discs and have had zero problems.