Shop Built Drum Sander Mk2 (slightly spammy)

Good idea. You need a finished diameter around 3.5", give or take, to fit sheet paper wrapped the long way so a 3-3/4" hole saw is probably about right, maybe 4" depending on the how thick the teeth are.

-Kevin

Trying to generate 3-1/2" slugs using a hole saw and a drill press will at best a slow job, not only the cutting, but especially when it comes to getting the slug out of the hole saw.

Think I'd consider a BIG table mounted router /w/ a BIG straight bit, and a clamping jig that will allow moving the jig /w/ the piece into the cutter, then rotating to finish cut the blank.

Lew

Or make one with the hole saw, and the rest on the router with a pattern bit.

(deja vu)

A production job in MDF?

A pattern bit?

Much faster and lower cost to use a standard carbide end mill.

Lew

Well, if I were doing it I'd still go with the band saw. Cut a bunch of 4" squares, drill the 5/8" holes in the center. Stack 4-5 at a time on a dowel for the cutting. No need to use a circle cutting jig, it doesn't have to be that accurate.

-Kevin

Your production requirements would appear to be at best only modest and as you indicate, accuracy is not a high priority.

Lew

On Fri, 10 Apr 2009 18:27:16 +0100, snipped-for-privacy@YAHOO.COM wrote (in article ):

Ta. I missed the links, sorry. I assumed you'd lathed them somehow.

The "no need to be accurate" but is interesting. Hadn't thought about the centrifugal self-limiting idea but it obviously bears closer scrutiny. I've seen the sand_flee video and that makes great capital of the ultra accurate machining that it employs so impressively.

Hmmm.. More than one slot and make it a big flap wheel? It'd use smaller sheets

Plenty of info now. I should be able to sit on the porch and whittle one up from an old log :-)

On Fri, 10 Apr 2009 23:27:53 +0100, Lew Hodgett wrote (in article ):

or maybe knock up a simple router lathe, running a router along an mdf track with a "log" turned by hand between centres below it.. \ no, hang that.. you're right. Do it on a router table with a free-moving jig

- a frame with two end-screws supporting yer log/composite, turn it and slide it along the drum axis, over the bit. Turn a bit more and make another pass... then raise the bit a tad and repeat. Tedious but maybe bearable for a one-off. Like a 3d version of cutting circles with a table saw jig.

OR use drain pipe with two routed end cheeks, an end-to-end slot with an internal backing piece to take your wedgie

stack of mis-burned CDRs ?

-MIKE- wrote: : snipped-for-privacy@YAHOO.COM wrote: :> But basically, it's just a bunch :> of MDF circles. I had 100 of them CNC'd, but you can just band saw :> them as they don't need to be accurate. :> -Kevin

: Would it be easier for someone with a good lathe to make one?

I think you'd need a metalworking lathe. It's actually quite hard to turn a perfect cyclinder freehand on a wood lathe -- you ca get close, but I end up taping sandpaper to a flat surface and using that for the final truing.

-- Andy Barss

Fly cutter

-- "We need to make a sacrifice to the gods, find me a young virgin... oh, and bring something to kill"

Tim Douglass

Still a slow process.

OK For one offs, but not production.

Lew