Need help with sanding scratches...

[Wayne Leach]

Hi All,
I am making some (4) new chairs for my 5th wheel using poplar( lots of it and free). The spindles for the legs are 2-1/2" diameter. I sand diligently thru the grits ending with 400 but when LOML applies the finish - boy do the scratches stand out like a sore thumb.
What can I put on to detect the scratches prior to the final finish? The finish is so tough to sand out and gums up the sand paper so quickly that it is not fun!!
Thanks in advance for the help.
Wayne

[Bernie Weishapl]

Wayne I use mineral spirits to detect sanding scratches or fine tool marks. Works well. Highlights them well.

[Wayne Leach]

Thanks Bernie, I will try that tomorrow night.
Wayne

[Steve Schlumpf]

Wayne - I agree with Bernie. Mineral spirits wets the wood down and you can spot all scratches real quick. Nice thing is the spirits evaporate quickly and do not leave a film.

[Dan Forman]

Are you sanding horizontally with the lathe off after sanding with the power on for each grit?

Dan

[Wayne Leach]

Dan,
I did sand with the grain after sanding with the lathe running and am now wondering about some of the sandpaper I used. It was some "crappy" cheap stuff I got from one of those mobile tool and junk peddlars. I couldnt resist 100 sheets of sandpaper for $1.00 so its going in the garbage. I think maybe the grits were not uniform so will use good stuff from now on. Poplar being so light colored and soft, its hard to pick out imperfections until its too late. Will try the mineral spirits on those I had done earlier. Thanks for the input its really appreciated.
Wayne

[Michael Mills]

When using the mineral spirits, bring a light down parallel with the turning. You will see much finer detail (scratches) with a light parallel than with just normal overhead lighting.

Mike

[Dick Strauss]

Wayne,
I've also noticed that using the bluish white led lights are great for spotting scratches on wood for some reason.

[Kyle Iwamoto]

I've noticed a big difference in the cheap sandpaper you get from the *mart stores and 3M or Norton and the better quality papers. The cheap stuff have big 30 grit rocks in them and they leave those scratches in your work.

[Roger Wilson]

...boy do the scratches stand out like a sore thumb...

Are you power sanding or just holding the sandpaper against the spindle with your hand ? Power sanding does a better job of producing a scratch free finish. But even so sometimes you have to stop the lathe and hand sand a spot or two.

+1 for using mineral spirits or DNA (denatured alcohol) to simulate having a finish on the piece.

Some people sand wet with the first coat of finish in order to get dust into the smallest scratches.

Another thing to do would be to vacuum between grits with a brush end on the vacuum.

[Wayne Leach]

Thanks for all the help guys.
I trashed the cheap sandpaper and power sanded with Rhyno starting at 180 and working thru to 400 I hand sanded after power sanding with the grain and applied mineral spirits and goodbye scratches. Wife is now a happy camper!
Wayne