Dear Robert: It doesn't look like LMI stocks this sanding disc anymore. It also doesn't look like there are any impediments to prevent me from making a sanding disc of aluminum, steel, or some high density press board. It appears the recesses for the cutter bits on the planer disc would require building pedestals of some sort to mount the retaining nuts, but good glue either epoxy or Tite-Bond should work for fastening these to the disc itself, then drilling and mounting the nuts with an epoxy matrix, taking care all the while to keep everything the same weight and size in order to provide a balanced assembly that shouldn't vibrate too much. What do you think? I already have an auxiliary table for my drill press that has a moveable rear fence, "T" tracks, and numerous inserts for attaching featherboards, mortising fixtures etc. to use with mortising bits, and other fixtures that will provide for vertical featherboards and other holding and clamping devices. What do you think is the maximum size disc that I should make? I'm beginning to think that I should just make a disc with an appropriately sized arbor with let us say, a 1/2 inch shaft not too long so it will be stable at speed, and forget the Safe-T-Planer altogether for thickness sanding. Perhaps a 6 inch aluminum disc about 1/4 inch thick for lower mass and stability would be appropriate, then run it no faster than vibration allows. It also seems to me that the closer to the chuck that the arbor flange is, the more stable and lower in vibration the tool would be in operation. Your input would be greatly appreciated. Best Regards Don Denison
I think if you get the disc too large it would be hard to keep it true while using the drill press. I prefer to just use the safe-t-planer and then a scraper to finish it off. If you decide to make one let me know how it goes.
Dear Robert: I did build a combination 6 inch by 48 inch belt sander/12 inch Disc sander years ago using a jack shaft and pillow blocks to run both the belt and the disc, with a 2 Horsepower motor complete with two tables of sizes large enough to be useful. I used a secondary shaft, itself mounted on pillow blocks and an arbor secured by key stock and the aluminum plate to make the disc with, roughed it out, then filed it close to my scribed line then allowed it to rotate against my coarse mill file at low RPM to true it up, I then balanced it by drilling the low side, found when I spun it without the drive belt installed. Building a suitable frame to support the tilting tables, and designing guards and dust ports was the biggest headache, I can't tell you how many board feet of lumber that home made sander has processed for me, that is why I thought of doing a light 6 inch plate on an arbor that would chuck in my drill press chuck, the one I have will take a 5/8 inch shaft easily. I have a Grizzly multiple speed 14 inch drill press which I have fitted an auxiliary table to for multiple usage. The biggest problem in using a drill press is finding the correct bearings in the right sizes, I used bearings in my press that were intended for use in a Vertical Mill, it makes it more stable and it will now take side thrust was well as down thrust without ruining the bearings. I worked for several years as a Millwright before an injury forced me into teaching, so your video got me thinking, I will build a rotary thickness sander of about 6 inches and see what transpires.. If a 12 inch disc won't shake things apart, a little 6 inch disc should be a piece of cake up to about 2,500 RPM, though it would still be useful at about 250-350 RPM, though at that slow speed I don't think it would work well for adjusting thickness. I'm running the 12 inch at 1750 on the motor, stepped it up slightly to about 2,000 for the disc. When I get this thing built, I'll give you a report. I believe this is probably a way to thickness tops and backs without investing in an expensive thickness sander. I presently am using a sled and my thickness planer to adjust thickness which works OK, but snipe is a problem occasionally regardless of how well I adjust the machine. A rotary planer would avoid that problem and the need to use a sled as well, given the proper use of featherboards and push sticks, I can probably avoid the purchase of a $1500 thickness sander. Then again, I might be able to convert my planer ........Nah, I don't think so! Best Regards Don Denison
Dear Robert: I take your point, and indeed have built my copy of a Gibson J45 successfully without a thickness sander, I say successfully, but I know where every tiny mistake is. My friend Michael Lewis, a well known Luthier in Grass valley once told me, "Don, the job isn't done until it i done and done perfectly, even if you have to tear it apart and start over". No one but me can spot the mistakes on the J45, but it drive me absolutely nuts. I am often to the point of just trashing it, though it plays, looks and sounds wonderful, I know where that scraper mark on the inside of the back is, I could never in good coincidence put it up for sale so I guess I either have to scrap it or tear it apart and start over. I have everything here but an arbor, and I believe that ENCO sells them so I will probably make a little 6 inch Rotary thickness sander on the lines of the one I have envisioned and described to you. I am an old fart of 75, I recently lost my sweet wife, and need to do something pretty much constantly to fill up the empty hours, so time is of no concern to me. I am gathering materials and other supplies to build a Classical Guitar, I may enroll in your online class. I have two Luthier friends here in CA that I can go to for advice as well, but your on-line class should keep me from being a pest and taking up their time. A Classical Guitar as you know is significantly different than a J45, so I will no doubt need guidance, I'll give you a report on the sander after I get it working and have something to tell you. When I get everything together for the guitar, I'll contact you about the on-line course. Best Regards Don Denison
No longer having access to the university woodshop, should I invest in a top quality drill press for this type of job? Or will an inexpensive benchtop model suffice?
@ 7:07 reaching around drill press with sleeve coming too close to spindle makes this video a failure. Shut off the camera and entertain yourself. After watching a couple of these videos , I was not impressed at all. If you cant figure these simple tasks out for yourselves folks, perhaps lutherie and wood working with power tools is a stretch. Please be safe.
