My wife was very sick today with a chest cold, so she and I both slept in. I spent much of the day indoorts helping her stay comfortable, attending to my chores for the day, and doing an indoor project which very much needed doing.
While the concept of inverting a hand sander on clamps to use as a micro miniature sanding station has all kinds of appeal, it has one serious drawback.
When power sanding the silver ingots for the first time the other day, I noticed:
1) Finishing with finer paper revealed pits needing smoothed out or eliminated with coarser paper.
2) The Dremel didn’t help… much. Except for eliminating genuine gouges and other serious mistakes, the barrel sander introduced more pits and spots thant it removed.
3) Great jumps in sandpaper fineness at the coarser grades should be avoided. I seem to obtain better results using gradual shifts through a wide series of grades.
4) Changing the sandpaper belt on the hand sander just to go up or down a single grit is tedious, error prone, and wasteful of sandpaper.
Now this type of sander uses an entire quarter sheet of sandpaper where the opposite sides of the paper are locked into place with levers before using. For convenience I call this a sanding belt.
I knew there had to be a better way of changing grits than turning the machine off and changing the paper every time, especially when all I wanted to do was move between grits easily and inspect my work as I go.
So I decided to design a type of sanding belt where I could change grits simply by moving my piece between different zones on the belt.
Since sandpaper was a precious material to me, I did not want to waste any of the sandpaper as belt mount. Instead, I decided to create the belt out of poster board (about the same thickness as coarse sandpaper anyway), and tacking down swatches of different grits of sandpaper whose corners would meet at the center of the belt.
Calculating layout of abrasive paper swatches...
I had bought a roll of Gorilla 2-sided carpet tape as an attempt to hold a silver ingot down on an aluminum block. That idea did not work because the adhesive was not strong enough to prevent the fly cutter from knocking the ingot off from the block.
However, in this exercise I was able to find a different use for the roll. I was very impressed by the strength of the fiber-reinforced adhesive layer of the tape between the poster board and the sandpaper backing.
(More impressed than I needed to be, it being so very bleeping hard to undo a mistake!)
2 sided carpet tape is applied to the layout poster board
I then cut 6 swatches of sandpaper for each for 4 grits that I wanted to mount into a sheet of poster board.
Lay down abrasive swatches on the carpet tape to form groups...
The groups are then cut apart and trimmed, yielding 6 sanding belts each with 4 different sanding zones.
... that are cut apart to fit as belts on an inverted hand sander ...
Now whenever I want to sand an ingot through a series of 12 grits, I only have to change 3 belts rather than 12. I also have six copies of each belt, a goodly supply for the near future.
To use, I simply apply the piece I want sanded to the lowest grit, and then slide the piece between grits, staying at each grit for a few seconds at a time!
inverted hand sander belt for low grits (60, 80, 100 and 120)
inverted hand sander belt for medium grits (150, 200, 400 and 500)
Inverted hand sander belt for fine grits (600, 800, 1000 and 2000)
