concave sanding wheel

[peteglider]

Hello guy's, not sure if this is the correct place to post this, but thought I'd ask anyway. I make wood fishing lures, and for certain models I use a chisel and file for rounding edges, some australian lure builders use a homemade 6-8 inch diameter wooden wheel with a concave groove cut into it . They then glue strips of garnet paper in the groove and fit the wheel to a motor shaft or bench grinder, they use this to round over and shape the corners. I'm thinking along the lines of maybe a 3/4 inch diameter groove. Any suggestions or advice appreciated. ......pete

 

[rafezetter]

How about one of those bench clamps designed to hold a drill in place then the wooden wheel etc?

I've got one and have used it with polishing mops no problem - you'd need to use a corded drill with metal chucks - toolstation do a basic one with vari speed iirc.

http://www.axminster.co.uk/shesto-unive ... amp-504095

 

[marcros]

Is this item secured to a drill chuck or a lathe? It sounds quite easy to make one on a lathe. Do you have a picture?

 

[peteglider]

Thanks for replies marcros and rafezetter, unfortunately don't have pictures. If you can imagine a 1.5inch wide mdf honing wheel with a half round groove cut into it , then mounted like a grinding wheel onto bench grinder shaft. I have a spare grinder shaft on a bench grinder I have my mdf honing wheel on so hope to use it. Basically looking at mounting
The wheel on grinder and cutting groove with a spindle gouge or even very course sandpaper. Thought I'd ask in case anyone used anything similar here before I make one , don't want to reinvent the wheel. ....pete

 

[Robbo3]

If you mean a groove in the rim of a disk, then that's just basic turning for anyone with a lathe.
Mount it on a mandrel to hold in a drill chuck. You can make a mandrel with two nuts, two washers & a short length of threaded rod.

 

[NazNomad]

So basically a wooden pulley wheel?

 

[Eric The Viking]

You could even do it, quite safely, on a router table. I have made pulleys that way, out of MDF.

The trick is not to do the grooving bit with the wheel horizontal, but vertical. But you do need a jig, and the right cutter. You might also make it as two discs, each with a quadrant cut out, then stuck together.

But... The intended RPM matters a lot. IF IT WILL TURN ONLY SLOWLY, you can make it in many different ways. If you want it to turn at the speed of a dry grinder, give up now and have it made in metal on a lathe, as you will be unable to balance a wooden wheel well enough to be safe nor without vibration in use.

 

[Phil Pascoe]

How do you get the abrasive to stick down and/or stay flat in a groove?

 

[Eric The Viking]

How do you get the abrasive to stick down and/or stay flat in a groove?

I was wondering that, too.

Overlapping thin strips going radially? It would be quite a fiddly thing to do...

 

[AndyT]

It does sound to me as if the desire to use a power tool might be distracting you from simpler methods.

You say you use a chisel and a file, but depending on the exact shapes there are many other hand tools which will round over an edge quickly and easily, including, in no particular order:

- knife
- gouge
- spokeshave
- block plane
- hollow plane
- Stanley corner rounding tool (now made by Veritas)
- rasp or riffler (with individual, triangular teeth), available in many shapes, to cut on the push or pull
- special carver's file, like the dreadnought pattern
- float
- Surform
- microplane
- coarse / medium / fine adhesive stuck to a wooden block / stick/ dowel.

But if you want a powered, abrasive method, is there any real need for the groove - can't you get the same effect from a readily available cylindrical drum sander by flipping the work from side to side?

 

[peteglider]

Thanks very much for answers and ideas, it's very much along the lines of that wooden pulley wheel but 6-8inch diameter with a wider groove. They use strips of cloth backed sandpaper (garnet?) Glued around groove. This allows the corners to be evenly and quickly rounded over resulting in a nice symmetrical curved back on the lure. I will try and show pics when I can. These guy's have been using this for 20 years with good results. I did succeed in making a 7 inch diameter 1.5 inch wide mdf honing wheel run true on bench grinder by doing as suggested, ie ,on mandrel on lathe, then mounted on grinder, used block and sandpaper to fine tune. Any more suggestions appreciated. ..pete