Aluminium spinners

[Keith Evans 3]

I've just spent nearly an hour trimming an aluminium spinner to accept an 11x6 prop .I carefully marked up a new blade outline on the spinner and then had to decide how to trim it back and with what .A junior hacksaw was fine for a vertical cut but what about the curved profile ? I started to use my Dremel to grind the profile but not one of the grinding bits in my collection were satisfactory ,they were all clogging up very quickly .In the end I cut the profile in very small stages using the small flexible grinding discs .I'm sure there must be a better way .Any ideas?

[Bob Cotsford]

I usually resort to a good, old-fashioned rat tail file (a round section file!) and a small half-round file. A Dremel sanding drum will work for small adjustments and finishing but I don't find the Dremel wheels much use on aluminium spinners otherwise. It's a situation where I find hand tools win over power tools.

[john stones 1 - Moderator]

Chainsaw files, flat ones and round ones, not expensive, cut nice n clean.

John

[Don Fry]

Crude but effective is a small size dremel sanding drum, used at about 12000 rpm, and keep the drum moving so you don't wear a band on the sanding paper. Mark the spinner so you keep it all symmetrical.

[iqon]

Why small .......4" Grinder...

[Denis Watkins]

Please be careful working thin sheet metal, it is just fraught with snags.

When the sharp edges may spin, clamp the job down somehow

[onetenor]

Any files,burr abrasives etc used on soft metals like brass, ali etc tend to clog up ( pick up/ pin ) ad stop cutting . An old trick I was taught is to rub the cutter on a block of chalk/ plaster .This fills the teeth softly and stops the pinning. It isly cleaned later I know t works with files which BTW a new file should not be used for while on steel. It should be chalked and used o softer metals first

[Bob Cotsford]

I'd forgotten the trick of using chalk when filing soft materials . Most spinners seem to be a relatively free cutting form of alloy with thickish walls, you don't see many that look to have been spun from ductile forms of ali. in the small to medium sizes.

[Mike T]

I dust my files with talcum powder. Keeps them clog free and smelling nice!

[Tim Flyer]

One tip I have is how to hold the spinner securely in a vice . When properly held filing with a curved hand file is easy and faster than Dremmel.

First put the spinner adaptor sideways and clamp firmly in a vice. Then secure the spinner bolt to it from the INSIDE of the spinner . This holds the spinner firmly for filing, and it can be easily turned around by loosening the bolt. Do not try filing things when holding in your hands as it is not efficient. Using a vice for filing takes. About 10 minutes even for large spinners.

Edited By Timothy Harris 1 on 03/05/2017 15:53:19

Edited By Timothy Harris 1 on 03/05/2017 15:54:15

Edited By Timothy Harris 1 on 03/05/2017 15:55:53

[Mike T]

It depends on how big the spinner is, but even well tightened up that's going to be a bit wobbly, I think.

If you set this arrangement up so that it projects from the left hand side of your vice, then you can use your left hand (assuming you file with your right) to steady the open end of the spinner. Vicky verky for southpaws...

[Alan Hilton]

It's not particularly safe but I use an end mill in my pillar drill

[Tim Flyer]

Yes Thanks Mike that's exactly what I do . Fix spinner on the side of vice . Hold with left hand to steady whilst filing with half round hand file. Doesn't move and just takes a few minutes.

Edited By Timothy Harris 1 on 09/05/2017 11:15:33