Rob's rant - Disc sanders and tip overlays

[RobHunter]

Hey all

Disc sanders

I have been wandering around hardware stores and browsing the Diy sites, with the mind on a Disc sander. Honestsly, I'm a
bit reluctant cuz of the fact that you should only use the one side to sand. Also, for the money I have I couldn't buy anything but a
6" one, and they all seem undermotored. I have a treadmill motor floating around with the right RPM and its 3/4 Hp, more than the
6" cheapies have by a 1/4 hp. Anyway I had this idea that instead of a flat disc how about a conical shape ??? My mind tells me this
would allow you to run a piece of timber across the usable face, with no danger of touching the other side. Also was thinking this could then be used
to grind lams, with a jig. Am I wrong? I'll give it a try after my trilam is done with>

Overlay tips

I was reading up on Phenolic bow tips and thought I would have a go, but didn't like the idea on my Boo backed tri lam. The most informative site I could find states that any natural
fibre works....with differing results in strength, Linen, canvas then paper. I then thought Bamboo is a natural fibre too and googled again and found that
Strand woven Bamboo flooring is bonded with a phenolic resin. So it may be suitable for limb tips for the faster strings. Also you could try Diy Phenolic tips with Flax and bamboo fibres etc for a
natural look. . DIY phenolic (known in US as Micarta) is made using Fibreglass resin (with a cure time of 2hrs)

Rgds

Rob

Yes Im on Forte pain killers and cortizone injections. First pain free hours since Mid march.

[rodlonq]

A conical disc sander sounds like a good idea but may be hard to implement. Bare in mind you will no longer be able to make flat surfaces on items because the face of a cone will be convex and result in concave surface on your work piece. I assume you intend the apex of the cone to be in the centre of the disc? Could be worth a try though if thats the result you are looking for. You will also have to cut a small segment from circular sanding discs to get them to sit properly on a cone. The joint could be a problem.

I have made micarta from some Auscam material. 16 layers came up to about 1/4" thick from memory. It is very strong but takes a fair bit of epoxy to soak the material well. You can use any material to make it. An old pair of jeans or work pants, I would lean to cotton over synthetics though, only so the epoxy could sink in better. I put it in the oven with steel g-clamps on it and cooked it for an hour at 80C. Was ready to cut up by the time it was cool enough to handle. Oven stunk a bit though and I got banned from doing it again

Cheers...... Rod

[bigbob]

Rob I dont know how much your budget may be but I got a 300mm disc sander from Hare and Forbes for around the $200 mark. Carbatec is a little more. Absolutely indispensable in the work shop.

[perry]

I used Flannelette and Bote Cote Epoxy to make my own Micarta, I cut lots of Strips of Material smoothed on Epoxy between each Layer, Wrapped it in Cling Wrap and then clamped it between 2 pieces of Wood for 24 Hours. Made for great Tip Overlays and Knife Handle Scales

Rather than a Conical Sander you could make a Spindle Mounted Drum Sander, In combination with a Jig you can grind Laminations and shape Risers, other Curved surfaces and even profile Bow Limbs without a Jig freehand. I've seen similar very expensive Tools at Carbatec

regards Jacko

[bigbob]

One problem I've found with a spindle mounted drum sander in a pedestal drill is they distort with tightening and become 'waisted' due to the distortion and causing inaccuracies. However in saying that I did persevere with one for quite some time.

[looseplucker]

I recently took a tip off a boo backed osage bow trying to profile the tips using the disc. Probably me being a dufus....but anyhow a 66" ntn bow became 61"ntn....

[rodlonq]

Rather than a Conical Sander you could make a Spindle Mounted Drum Sander, In combination with a Jig you can grind Laminations and shape Risers, other Curved surfaces and even profile Bow Limbs without a Jig freehand. I've seen similar very expensive Tools at Carbatec

regards Jacko

What Perry said..... A spindle sander is much more versatile than a disc sander when making bows.

Cheers...... Rod

[Stickbow Hunter]

I then thought Bamboo is a natural fibre too and googled again and found that
Strand woven Bamboo flooring is bonded with a phenolic resin. So it may be suitable for limb tips for the faster strings.

IMO any reasonably hard wood would be fine for tip overlays with strings made of modern materials.

I wouldn't put a sander near tip overlays. IMO a couple of rasps will do the job quickly and will be more precise with much less risk to the bow.

I have neither a disc or spindle sander but have two linishers - one used upright where I use the end for grinding my lams and the other mounted vertical which I use to shape my riser fades before glue up and also to sand the sides of the limbs.

Jeff

[looseplucker]

I wouldn't put a sander near tip overlays. IMO a couple of rasps will do the job quickly and will be more precise with much less risk to the bow.

Jeff

What Jeff said.