BCM Community

Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: Charles in SC on March 17, 2010, 06:47:36 PM

Title: Metal finishing question from Feb BCM
Post by: Charles in SC on March 17, 2010, 06:47:36 PM
In the February issue of BCM on page 24 the red bus interior has some engine turned looking area. I know this may be a laminate but I would like to find out how this was done on aluminum aircraft cowlings in the 20s and 30s. Does anybody have a link or some info on this?
Thanks!
Title: Re: Metal finishing question from Feb BCM
Post by: paulcjhastings on March 17, 2010, 07:08:36 PM
Lay out the pattern for the size of circles you are using, and go to town with an abrasive disk. I haven't ever done it before but I bet you could even use a roloc scotchbrite disk. Chemetal tm makes sheet goods in brass, copper, and aluminum prefinished.
Title: Re: Metal finishing question from Feb BCM
Post by: wildbob24 on March 17, 2010, 07:09:45 PM
Charles,

Here's one:

http://volvospeed.com/Mods/engine_turning_jewling.html (http://volvospeed.com/Mods/engine_turning_jewling.html)

Bob
Title: Re: Metal finishing question from Feb BCM
Post by: JackConrad on March 18, 2010, 05:50:44 AM
    I put a piece of 3/4" dowel rod in my drill press, and applied black (emery) polishing compound to the bottom of the dowel rod. I clamped a piece of 1x2 to the drill press table and went to town, slightly overlapping the turns. When that row was finished, I moved the 1x2 and did row 2, then row 3, etc. Add compound as needed. Larger dowel rod creates larger turns.  A coat or 2 of clear coat will keep it nice and shiny.  
    We opted to not use this on our dash as originally planned because I was concerned about glare off this when the sun was in that "just right" position. We went with flat back dash panels for that reason.  Jack
Title: Re: Metal finishing question from Feb BCM
Post by: Dreamscape on March 18, 2010, 06:23:34 AM
I haven't had the priveledge of doing that but I did read that if you do as Jack suggested it willl work and come out nice. ;)

I had thought of doing that on our dash, thought it would look cool. I ended up with oak on the gauge panel cause I was in a hurry. ;D

Paul
Title: Re: Metal finishing question from Feb BCM
Post by: Charles in SC on March 18, 2010, 05:31:59 PM
Thanks for the responses. The link provided above takes you to a picture of the Spirit of St Louis which is a good example of what I am wondering about. I am of the belief that their must have been a better way of doing this. The size of this cowl would have made it pretty tough to have mounted it in a drill press and this was done on some rather cheap (at the time) planes. For a number of years I have tried to think in terms of the tools and stuff they had at that time. I am not even sure they had hand drills back then much less laser guided milling machines at their disposal. I am thinking maybe they did it with a brace and bit with an abrasive on it or something like that.