Engine Turning

[rooster57]

Any body got any info on engine turning design on aluminum. like tool type design examples, basic how to. Its the swirl design on the cowl of the spirit of st .Louis.

 

[Baby Huey]

I used to have several links to sites on line that showed the basic" How To".....Just go to google or what ever and type in Engine Turned, or Engine Turning and pick thru the list.

I can say this, I have personally tried it at work, just foolin around on sheet aluminum. It takes lots of patience, and a steady hand on the drill press handle. You MUST keep the same pressure on each stroke or you will have heavy marks and light ones, so practice on scrap pieces.
As for the bit.....you can use anything that will leave a mark. Ink erasers, small round brushes, sanding patches glued to wooden dowells, wooden dowells bare, wooden dowells with a little toothpaste, or polishing or rubbing compound, There are also "kits" that you can buy I think.
Just experiment around with stuff, you'll get the idea.
Good Luck ! "BH"

 

[Wild Mango]

The circular swirls are made with a rotating buff made of rubber or felt chucked up in a drill press or a Mill. The surface to be engine turned is coated with the desired grade of abrasive and the buff "stepped" across the surface. Looks cool, and back in the Spirit of St Louis days, Ryans would have engine turned the beaten aluminum cowls to give a pleasing appearing surface finish, the cowl material being too thin to be final sanded nice and flat. It also scatters the reflections.
I have done a lot of rifle bolts using a rubber plug cut out of an old tyre sidewall with a wad punch and fine grinding paste, in a mill drill. Looks neat there too.

 

[EX JUNK]

I think Track T might have some suggestions for you. He has done quite a bit of it on his build. Perhaps, when he sees this post he'll respond.

 

[oldtman]

If the part is small enough you can fasten it to a rectangle piece of plywood. You build a large picture frame with solid backing then set the piece inside and with spacer strips the same width as you want the turning spacing . turn the spot then pull out a strip then move over and set the strip on the other side and work across. this will give even turned spots. A milling machine is easier if you have one and keep the numbers straight as you move across.

 

[RPM]

Yea we need Track T to comment on this. He is the man. He does beautiful engine turning. I have done some. I used a wooden dowel in a drill press with valve grinding coumpound on the end. Very time consuming and it is hard to get it all even.

 

[Track-T]

Not much I can add, I used a flat head screw in a drill press, I've
done it from 4-40 screw to a 10" sanding disc......

 

[rooster57]

I would like to do the alum cowl plate i have . I have a Mori seiki mill i can program to make canned cycles and duplicate the move over and over. And it will duplicate the same tool pressure. But it sounds like practice is the key. i think i would do 1 inch circles. I do have dotco abrasive disks in 5 or 6 varieties.

 

[rooster57]

i found this on utube if your interrested.
[ame=[media=youtube]jf5dqUIT-eo[/media] - Sopwith Pup how to burnish engine turning finish in aluminum aircraft panels[/ame]

 

[EX JUNK]

Thanks Rooster, I really enjoyed watching that video.

 

[rooster57]

Me to i like it when someone posts the things that dont work with the things that do.

 

[T-Rex]

I'm pretty sure you can buy the burnishing sticks from Eastwood.

 

[rooster57]

Yes they came up on the search 35.00 for the 1 inch at eastwood. I need to see if i can find a 1'' collet or find out if i can turn it down on one end to fit a CAT 40 5/8 collet tool holder.