Please read before diagnosing... I have watched so many instructional videos, read so many threads and magazine articles, and continue to experience ongoing struggles with "swirls" or "pig tails" after sanding my projects. I thought explaining my current approach might help the crew here give me some ideas as to what to try next.
Let's suppose I'm building a table top:
- After rough lumber has acclimated to my shop and has been surfaced/prepared
- As I clamp/glue, I use shop-made cauls to help ensure close alignment between the edges of each board
- An hour after clamp/glue, I carefully/gently scrape squeeze out on both sides of the table (I find that glue is easy to remove this way.. I temporarily move a clamp, scrape that area, replace the clamp for overnight, and so on...)
- The next day, after clamps are removed, I use a combination of card scrapers and hand planes to blend joints as needed. This typically results in a surface that has only minor imperfections that I can detect with my fingers.
- For large surfaces (e.g. a dining table top) I then get busy sanding using my larger sander which is a Bosch 6" ROS, model ROS65VC-6. I usually run it on speed 5 or 6 (which are faster settings on this tool).
- I begin around 100 grit and progress to mid-200's, never skipping a grit along the way. I have tried multiple types of Aluminum Oxide discs.
- I progress about 1 linear inch in about 5 seconds, with the grain, overlapping passes, and the sanding disc sitting flat (not tipped). I typically do 2 such passes per section before incrementing to the next overlapping section. To give you an idea, to sand my current table top (measures 3.5 feet wide x 7.5 feet long), it took me about 2 full, non-stop hours to progress through the grits.
- I have good vacuum suction pulling through the sander the entire time for all grits
- I brush the surface clean each time I change grits
- In terms of downwards pressure, I am barely pushing downwards at all... Just enough pressure to keep control and guide the sander. The disc spins freely across the surface and I am not bearing down aggressively.
- I have changed the pad on the sander, and also tried a much softer pad.
After all of this, and without fail, I find widespread swirls across my work. Sometimes what I would consider "very noticeable" and other times "probably only noticeable to a woodworker". I either choose to live with it at that point or spend hours and hours and hours (literally 5-6 hours) painstakingly trying anything under the sun to resolve the issues (more card scraping work, hand sanding, endless power sanding with 300 grit, etc.).
As two points of reference:
- As a much less-experienced woodworker, I used an old Porter Cable 5" ROS and took none of the care noted above to achieve flawless results (even when judged by my current eye)
- For smaller pieces, I use my smaller BOSCH ROS20VSC and follow all the same steps as noted above.... and get swirls galore.
At this point, I really must wonder:
- Am I missing something extremely obvious?
- Are my expectations out of line? That is, should I expect that it truly takes every woodworker 10+ hours to sand a table top?
- Is it possible that 6 different brands of sand paper are all a problem? Is alum oxide not an ok choice?
- Are my Bosch sanders to blame? (I am 150% willing to write a check right this minute to buy 2 new Festool sanders [or whatever the group thinks is best] if that will help me past this issue)
I'm open to anything.. I'll even video tape me working on a table top if that would help. I'm going absolutely mad over this
Thanks!!
Bob R.