[cyclopsblown34]

I have a set of old aluminum slots for my 75 F-word highboy 4by and I want to remove the circumferential machining marks in them prior to polishing. ANybody got any ideas short of a small flexible block and loads of hand sanding? I've done that to one rim and spent about four hours on it. My hands are just a bit sore.

Thanks in advance for any ideas,
Chip.

[35terraplane]

Originally Posted by cyclopsblown34

I have a set of old aluminum slots for my 75 F-word highboy 4by and I want to remove the circumferential machining marks in them prior to polishing. ANybody got any ideas short of a small flexible block and loads of hand sanding? I've done that to one rim and spent about four hours on it. My hands are just a bit sore.

Thanks in advance for any ideas,
Chip.

Sanding is about the best way, on steel I use a 3M deburring wheel, it is very hard and works good, other than you have to watch holding it in one spot too long. I really don't know if they make something like that for aluminum, but I think for the best look you are going to have to sand.

35terraplane

Live everyday as it is your last, one will.

[TubeTek]

With modern tooling and cnc lathes you can put a turned finish on aluminum that can be taken straight from the lathe to the buffer. But most slots from the 60's and 70's were turned on tracer lathes where the main finish requirement was git-r-done. Although its a lot of work, sanding really is the best way to prep for polishing. There are other methods that'll take the lathe marks out, but you're about sure to end up with a wavy surface that'll show up after polishing.

[35terraplane]

Originally Posted by TubeTek

With modern tooling and cnc lathes you can put a turned finish on aluminum that can be taken straight from the lathe to the buffer. But most slots from the 60's and 70's were turned on tracer lathes where the main finish requirement was git-r-done. Although its a lot of work, sanding really is the best way to prep for polishing. There are other methods that'll take the lathe marks out, but you're about sure to end up with a wavy surface that'll show up after polishing.

Tube Tek is right, after runninmg a machine shop for almost 40 years the new CNC machines would give you a polihed look back then, not so good

[cyclopsblown34]

Thanks for the advice and education. Looks like I'll just take my time and sand them whilst watching the tube in the shop between client vehicles. This site rocks.

[Runnin'OnEmpty]

Chip, what grit are you using?

You might try a more aggressive grit to start, then go
to finer grit......or try wet sanding, or maybe emery cloth.....

[redsdad]

Got a brake lathe? Had a friend who had one. Put the wheels on the unit. Instead of the cutter, he rigged up sanders and then buffers. Easier on the fingers and arms. And you can step away from it for short periods to do something else.

[cyclopsblown34]

Nope, no brake lathe. I snuck up from 400 grit to 220 and went finer from there. It seemed to work pretty well. The sucky part is getting a proper support/block for it. I've been using everything from hose to soft sanding blocks and cut down stir sticks.

[35terraplane]

Originally Posted by cyclopsblown34

Nope, no brake lathe. I snuck up from 400 grit to 220 and went finer from there. It seemed to work pretty well. The sucky part is getting a proper support/block for it. I've been using everything from hose to soft sanding blocks and cut down stir sticks.

I agree with no lathe, you would have to have it chucked dead round and hope the wheel where you are sanding is, or you could have bumps in it. I agree with on Runnin on empty, start with a rougher grade and go up, I think that is what you meant when you said you snuck up from 400 to 220, I think you had them turned around, I did my 33 grille shell that way only I did not want the shiny look, more brushed, I did just the outside rim, left the teeth alone. That was all hand work. Once you get it pretty close, you can take a small polishing cone on a drill and use some rough paste of that, right up to jewelers rouge. East wood has good stuff for that. I'm doing all the aluminum on my engine. The valve covers are smooth, but the plenum is kind of rough. that will be a little harder. One bad thing about aluminum, it will load up paper pretty fast, depending on what grade of aluminum it is, so you might have found that out, as you have done some already. What to use for support is just keep trying different things which it sound like you are. I guess if working on cars was going to be easy, everyone would be doing it.

35 terraplane

live everyday like it's your last, one will.

[ericnova72]

Originally Posted by cyclopsblown34

Nope, no brake lathe. I snuck up from 400 grit to 220 and went finer from there. It seemed to work pretty well. The sucky part is getting a proper support/block for it. I've been using everything from hose to soft sanding blocks and cut down stir sticks.

Sections of radiator and heater hose can be effective curved blocks also.

The lathe or some other spin fixture to spin the wheel and flap sanding wheels followed by sisal wheel buff with compound and cotton wheel buff is how forged or spun formed wheels are polished by companies like Centerline and Weld. I know because I worked for a company that made Sprint car and Modified wheels, and bead locks.

I polished several sets of old slot mags for myself and friends on off hours, the company had a special buffing machine that spun the wheel in reverse of the flap wheel and buff wheels, and had foot pedal hydraulic adjustment on the angle of the wheel being polished. It was slick, a custom machine we built just for that purpose. Tried buffing an old wheel with just rough compound and the sisal wheel, then cotton buff, but it never looked good, you have to sand the discolored oxidized skin off, then the buff steps to get a wheel that reflects like a mirror. 400 grit greased with Crisco was the final sanding step on the machine, but you may have to go finer by hand to minimize buffing time. Greasing the paper prevents it loading up, just like wet sanding does.

[cyclopsblown34]

Thanks Eric, I'll remember that. I was gonna try the cartridge rolls on a die grinder with the air turned way down. The crisco is one heck of an idea. Maybe I'll get to work on it Sunday.

[Runnin'OnEmpty]

Originally Posted by ericnova72

......400 grit greased with Crisco was the final sanding step on the machine, but you may have to go finer by hand to minimize buffing time. Greasing the paper prevents it loading up, just like wet sanding does.

I've been around the car hobby a long time, but this is the first time
I've heard of using Crisco......except for frying chicken.....

[35terraplane]

Originally Posted by Runnin'OnEmpty

I've been around the car hobby a long time, but this is the first time
I've heard of using Crisco......except for frying chicken.....

What's been runnin'OnEmpty?
I guess I never had either, but I wasn't saying anything until someone else did

35terraplane

If you're not living on the edge, you're taking up to much ground.

[ericnova72]

Originally Posted by Runnin'OnEmpty

I've been around the car hobby a long time, but this is the first time
I've heard of using Crisco......except for frying chicken.....

I know, sounds funny , but it was basically just a cheap easily available replacement for the expensive "special" sanding belt dressing from the folks that provided the rouges we used for buffing aluminum wheels, beadlocks, and "mudslingers"(a beadlock/moon disc 1-piece combo to keep mud buildup out of sprint car wheels to avoid throwing the car set-up off mid-race). We paint it onto the spinning belt(3'"x 12' industrial belt buffer stand) or the wheel with a medium size paint brush.

[jon72vega]

I've used Crisco to lubricate a reamer when reaming a small hole in aluminum.
It keeps the cutting flutes from loading up with the metal you are removing.

Jon
http://1972vega.wordpress.com/