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View Full Version : Pen still showing scratches after MM. Help!



Aaron Buys
04-23-2008, 9:16 AM
So I've turned 2-3 Barons in the past month or two and I'm having a hard time getting the super smooth sanding job I want. I've been sanding to 400 grit and then switching and going through all the levels of micro mesh but I'm still left with some deeper scratch patterns than I'd like. They aren't real noticeable unless you hold the pen at an angle with with very good lighting. From what I can tell they are scratches left from the 150 grit but even with extensive sanding with with the 250 through 400 I'm having a hard time removing them. On one of the pens I sanded for what seemed like an eternity with the 1500 MM and that seemed to take care of it but I'm assuming there is an easier way. Any suggestions on what I might do to either prevent these scratches from the start or remove them more effectively? Am I just being too picky?

Bernie Weishapl
04-23-2008, 9:19 AM
Aaron I usually sand to 800 to 1000 grit then go to MM. During the sanding each grit I stop the lathe and turn the spindle by hand as I am sanding from end to end.

Tim Brooks
04-23-2008, 9:57 AM
Try to make smoother finishing passes with your skew and stop using the 150 grit. Start with 220 then to 400 and MM. Works great for me. The key is to finish with smooth tool passes so you do not have to use the lower grit paper.

If you have to use the 150 grit, let the paper do the work. In other words, don't press so hard.

Just a couple of thoughts.

Ken Fitzgerald
04-23-2008, 10:16 AM
One of the things that was recommended to me....after turning with the lathe rotating......stop the lathe using the same grit...sand the length of the blank while rotating the spindle manually....then wipe or using air blow off the entire blank to remove any sanding grit left on the blank before going to the next hire grit.

However, as stated by Tim....I primarily use a skew for my pens and I could probably start at 400 grit and go up

Steve Mawson
04-23-2008, 10:24 AM
I agree with Ken and Tim. Blanks should be smooth after last pass with lathe tools. Then start with 220 or even higher if you are doing a good job with the SHARP tools.

Aaron Buys
04-23-2008, 10:51 AM
Thanks for the advice guys. The skew and I still don't get along real well so I've been doing most of the work with a small gouge and thus leaving a surface much in needing of sanding. Perhaps I need to cut up a few 2x4's and spend some quality time with my skew.

Bernie: Are you using water with the sandpaper at the 800 and 1000 grits? I have some 800 but it's supposed to be used with water. I'm always hesitant to use water on dried wood since I'm adding moisture back to the piece.

Phil St.Germain
04-23-2008, 10:58 AM
Aaron,

The skew and I never got along until I started using a bigger skew. I use a 1 inch skew for all of my pens from start to finish. This improved the quality of the pen and reduced the time needed for sanding.

Tony Wheeler
04-23-2008, 11:09 AM
another thing that I do is reverse the rotation with each grit but not everyones lathe can do that

Greg Cuetara
04-23-2008, 11:10 AM
I know others here are much more experienced but I will put in my 2 cents. I used 150 grit on my first few pens and I couldn't get out the sanding marks created by the sandpaper. After I turn the blank round with a gouge I turn to my round nose scraper and that has gotten the pens fairly smooth then I can start out with 220 or I prefer now to start out with 320 then to 400 and I have wet-dry 600 that I use dry. After all the sanding I use EEE ultrashine woodturners's finish which is a micro abrasive and just goes on like a friction finish but it is not a finish. It is supposed to be used under shellawax but I have been using it under a BLO / CA finish and my pens have been coming out very smooth.

If you do decide to keep up with the 150 let the paper do the work and then I would go to 180..make sure all the scratches are out from the 150 then go to 220 and make sure all the scratches are out from the 180....it becomes progressively more difficult to get out scratches which were made by course sandpaper by much finer sandpaper. I have heard that one or two steps of finer sandpaper will be able to get out coarser sandpaper scratches but any more than that and it almost becomes a futile effort.

One last item. Between sanding grits I typically burnish the wood with shavings. This will clean off the wood of any misc. grit pieces which have been left behind. If you go onto a finer grit and there is a bigger piece left behind you will cause more scratching etc while you continue.


Good Luck,
Greg

Daniel Heine
04-23-2008, 11:22 AM
Hello,

This may not solve the scratch problem, I suspect the 'scratches' are small grooves left from the turning process. I used to get valleys and hills when I used my round edge scraper. Before I even start sanding, I go over the pen once or twice with a large skew. Then, stop the lathe and rub your hand over the blanks. If you feel anything but smooth surface, go over it again with the skew until it is flat. Then sand. If you are turning acrylics, I found a product called Novus. They have a coarse and a fine scratch remover. After applying the fine scratch remover, the pen will just glow. I don't even bother buffing my acrylics anymore. I sand to 1500 grit, then MM to 12000 and finally the 2 Novus treatments.

Dan

Edward Herbster
04-23-2008, 12:04 PM
First of all DO NOT use water on your sandpaper if you turning wood. Take a peice of wood about 3/4 to 1" wide and wrap a piece of lets say 150 to 200 grit sand paper around it. Go over your pen untill any hills, valleys or tool marks are gone. Do not press hard let your sandpaper do the work. Get rid of the stick and sand with the grain with the lathe off, spin the lathe by hand. Wipe the pen wth a paper towel to get any residue off and then turn the lathe back on about med speed and continue sanding with the higher grade sand paper using the same system as above without the stick. Be sure to remove the sand paper before you turn your lathe off. I sand to 1000 grit then MM and then turn the lathe wide open and pollish with a piece of paper bag from the grocery store. Put the polish of your choice on and I think you will be pleased with your results.This works great for me.
PS If you still see sanding marks after 220, continue with it untill they are gone. Because if you try to sand marks out with anything higher your wasting your time and sandpaper.
Good Luck And teach a child to turn!!!!
Herby

Steven McLoon
04-23-2008, 2:49 PM
Aaron-
I too am skew-impaired but am working on this problem. Lately, I have been using a skew with a curved cutting edge as advocated by Alan Lacer. That helped a lot. Just yesterday, I ventured back to my straight edge skew on a pen with success. I still lack confidence and will revert to the gouge if I feel the wood is precious or the project particularly important.

I also went through the persistent scratch problem. As I gained experience (one year now), my quality standards went up, and I had to deal with the scratches. I did several things, and I am not sure what made the difference. Here is my list:
1. At the end of each sandpaper grit, I stop the lathe and sand the length of the pen barrel until only longitudinal scratches remain. I then sand with the next grit radially with the lathe running. I sand until the long scratches from the previous grit are just gone. Next, I stop the lathe and sand longitudinally …
2. Between each grit, I briefly wipe the pen barrel with a soft cotton cloth to remove sawdust and abrasive debris. Particularly the courser grits of sandpaper can leave debris that will be a plague on subsequent sanding steps.
3. I minimize contact between the sandpaper and wood so that the sawdust and debris can clear. I never wrap sandpaper around the barrel as this can result in loose abrasive debris becoming embedded in the wood (and it does not sand well).
4. I use good sandpaper, which generates less debris.
5. After the final micromesh, I use EEE, which seems to remove any final scratches.

Goodluck.
-Steve

Chris Stolicky
04-26-2008, 7:47 AM
As many have said above, and some other things I have found that works:

- Try to finish as smooth as possibe with the tool. I have always used a 1/2" oval skew on my pens and it works great. I tried a 3/4' and bad things happened!

- I have never started with a grit below 220 on a pen. I have found that starting with 150 on a bottle stopper sometimes creates pretty deep scratches that take a lot of effort to get rid of.

- Always wipe off dust/debris between grits. The larger particles left on the piece will be pushed into and will 'cut' into the material you are tying to sand.

- When using non-wood material, I use the plastic polishing pads (similar to MM), and then have learned to use a dab of polishing compound on a rag (I use the $1.77 turtle wax variety from the local auto parts store) and it really does a good job! The idea with this is that it uses a very fine grit and slurry to polish with. I have heard people use this on wood, but I haven't tried it.

Good luck.

robert hainstock
04-26-2008, 9:16 AM
My system , and it seems to work for me is. 100, 150, 220, 320, 400, and 600 grits. Then I apply auto body polishing paste, (white diamond) to a piece of rough cloth, (Drapery); and polish the blank at high speed. The lateral sanding works on really deep scratches. Lately I've been buffing them and have gone to the CA finish. It is not that much better, but is much quicker, (20 mins vs 3days for poly). :)
Bob