|Project by Bob Areddy||posted 02-01-2009 03:52 PM||32789 views||92 times favorited||27 comments|
Just put this up to showcase my home made 22” drum sander. I HATE sanding. And trying to get a glued up panel perfectly flat is time consuming and dirty. So I found a plan on the internet which I adapted to a larger unit.
The drum is approximately 5.5” in diameter. The sand paper is held on with velcro. I bought the motor on Ebay for a steal, around $60. The table I already had laying around for the last couple of years, as it was going to be my workbench top. Nearly the entire base is made from 2×4 construction lumber, except for the horizontal members which hold the pillow block bearings (which I also bought on ebay).
The velcro mat and sand paper comes from Woodmaster Tools, whose website really blows. You’d think they would have all the sand paper in one section.
The drum is made of 3/4” MDF discs that I cut using a router. I think there are 32 of the discs, with a 5/8” hole drilled and placed on a metal rod I got from Home Depot. If it were any longer, I would use a 1” rod to stiffen it up, however gluing all the discs up made for a rock solid cylinder. I used regular yellow carpenter’s glue.
The cylinder rides in pillow block bearings, and once mounted, I trued it up by taking a 3” wide board and gluing some of the 80 grit sandpaper to it. Then, holding the board down on the table with the paper side up, I raised the table so that the drum would just touch the paper. I moved the board across the length of the cylinder to smooth it down, and this would also insure that it was parallel to the table. I put pencil lines all over the cylinder so I could see where I sanded and see the low spots. I kept raising the table until all the pencil lines were removed. Kinda like an upside-down lathe with a sand paper cutter.
Once the cylinder was round, I glued the velcro backing to it, spiraling it around from end to end. I used a spray adhesive for the glue. Once the glue is dried, I wrapped the sandpaper around it in the opposite direction.
Other features of interest might be the motor mount. It’s mounted to a piece of plywood, which is hinged to the base of the unit with a piano hinge at about a 45 degree angle down from horizontal. This allows self-tensioning of the belt… I have no idea if it’s the right amount of tension, but it sure seems to be right.
The table is hinged to the base as well, and a simple threaded rod with a home made handle is the raising mechanism. It’s great for table tops, but I can only get about a 1” thick piece under it. I may retrofit this to get another 3/4” room… I could also remove the drum and raise the pillow blocks to achieve this.
Since these pictures were taken, I’ve added onto this unit by making a disc sander attachment and table by using the rod that is sticking out in the first picture. It’s a 9” disc, and has a table that can be tilted up to 45 degrees.
For a few more pictures, visit my site:
-- --Bob http://www.areddy.net/wood