Harley; Your Proxxon disc sander may be a precision piece of equipment, but you'll be disappointed with the job it does in this application. You'll discover the same disadvantage that all disc sanders have, namely that the outer edge of the sanding disc is traveling many times faster than the center so will remove more material toward the outer edges. Since you have a sanding disc that approaches 10" in diameter and you want to bevel sand end caps that are in the 8"-9" range, your end cap will stretch almost all the way across the sanding disc from one edge to the other. What you'll find with the outer edge of the disc rotating at many times the speed of the center is that your end caps will end up with a curved surface. Yes, the end caps will be nicely beveled, but when you trial fit one to another, you'll find that there's at least a 1/16" gap at both the leading and trailing edge with the middle of the end cap fitting flush. This makes it very difficult to get a perfect fit between the center panel and your tip panels. A belt sander with a bevel sanding attachment and appropriate jig will provide a straighter edge and much better fit. I tried using a 12" disk sander to ensure perpendicular edges in two axis for quad taper wing panels and it's essentially unuseable in that application.
Good luck with your project, but I think you'll also experience this problem as it's nothing more than it simple geometry at work. Fred Fred ----- Original Message ----- From: "Harley Michaelis" <[EMAIL PROTECTED]> To: "Soaring" <[EMAIL PROTECTED]> Sent: Sunday, October 12, 2003 11:37 AM Subject: [RCSE] I got the Proxxon disc sander! > Wow. . .this is a beautifully engineered, precision piece of equipment! > > I got mine from Klingsport's Woodworking Shop in SC for $229.80. UPS ground > was only $5! Call 1-800-228-0000 or see www.woodworkingshop.com for on line > ordering. Their stock # is PX38060. > > I've been using a Sears combo 6" disk and 4" x 36" belt sander with great > frustration. It is so noisy, so badly balanced, the faceplate for the disc > wobbles, you can't get the table horizontal, the belt cannot be tightened > and it has ground away at the front of the table, on the edges of the dust > collector housing, etc. etc. The belt has a thickned area where it joins and > this goes thunk, thunk, thunk causing great annoyance. > > I decided to pamper myself with the Proxxon, which is a 10" (almost) disc > sander. I am so looking forward to using this. The face plate for the > sanding disc is double ball-bearing mounted and it turns with no wobble. It > is variable speed to slow down the RPM for delicate work. It came with some > 80 and 240 grit sanding disks. They are interchangeable because the neat > backing adhesive allows them to be peeled off and reattached at will. > > My primary intent for this machine is to bevel hard endcaps that go on foam > cores to precise dihedral angles. In particular, this will be used to do > that where the tip sections butt the center on my GENIE sailplane. The chord > where endcaps butt is less than 10", so I can do the whole endcap at once by > pushing it against the sander. I bevel these endcaps before attaching them > to the cores. > > For that purpose, I've made a little sliding platform with rails on its > underside that precisely fit the sides of the 4-5/8" x 11" sander table. On > top of the platform, I've placed a 3/4" square rail parallel to and near the > faceplate. The work will be placed against that rail and the platform will > be slid against the sander to make the bevel. The table is set at 90 degrees > to the faceplace. The platform will be shimmed at its front edge to sand the > work to the desired bevel. Useful "rule of thumb" is that a 1/16" rise in > 3-1/2" is one degree. > > Of course, now I have this marvelous machine for all the usual things done > with a disc sander. > > Harley Michaelis, 26 S. Roosevelt, Walla Walla, WA 99362, ph. (509) 529-2562 > > RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED] Please note that subscribe and unsubscribe messages must be sent in text only format with MIME turned off. > > RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED] Please note that subscribe and unsubscribe messages must be sent in text only format with MIME turned off.
