Durable cheap finish for home built receiver

AL won't parkerize , and 304SS???

"David R. Birch" wrote in news: snipped-for-privacy@news7.newsguy.com:

I can't help with the aluminum (Magic Marker?), but rust bluing is very durable & free. All it takes is lots of time & work. There are chemicals that speed up the rusting that you can buy, but boiling salt water under it should suffice. Or leave it over a vat of any one of a number of other corrosive chemicals you probably have around or can scrounge.

Doug White

Doug White wrote in news:Xns9DFEB3634F50Egwhitealummitedu@69.16.186.7:

Ooops! Just noticed it's stainless. You may still be able to rust blue it, but it's gonna be harder. A good baked rattle-can paint is probably your best bet.

Doug White

That settles it. Pick up a pint of 1,200 degree, matte-black stove paint and brush 'er on!

-- Some people hear voices. Some see invisible people. Others have no imagination whatsoever.

OK, it's clear now that it is a gun receiver. I'd look at black hammertone or a fine wrinkle finish, baked or catalysed.

Come to think of it, the same I'd use on the Heathkit.

How about a Magic Marker? Lots of colors!

I appreciate David's position...but if I had just finished all that machining, I wouldn't cheap-out on the finish.

If you already have a battery charger, or know somebody who can lend you one for a day, you can anodize aluminum at home for practically nothing:

As for the stainless, I have no idea what this stuff costs, or what alloys it works with, but hey, it's a start: (I googled "black oxide".)

Cheers! Rich

:^)

Oddly enough, I was just researching online Heathkit manuals for my AR-14 receiver which is starting to act flakey. I remember the AR-15 Heathkit as state of the art at the time.

David

>

Someone else suggested Crayola.

:^)

Fun, but a bit short in durability.

David

[ ... ]

There were three versions of it:

AJ-15 FM Tuner only.

AA-15 Power amp & preamp only

AR-15 All of the above in a single chassis.

I built the AJ-15, made a rack mount for it, and used it for many years.

The big nuisance was the number of pilot lights behind the panel, and how difficult it was to dig in and replace them. Now *that* was something which would really have benefited from LEDs. :-)

I was at the time using an amplifier and preamp of my own design and construction.

Enjoy, DoN.

Or you could have put a diode in series with them and run them at around half power. A pair of diodes would let you put half on each half cycle.

Around 1970, my father built my AR-14. I built the amp/preamp only version, the AA-14. There was also an FM tuner called the AJ-14.

The AR-14 had tape outputs, the AA-14 didn't, but the preamp circuit boards were the same, so I installed the necessary components and drilled holes in the back panel for female RCA jacks. I still have both units, but the manuals wandered off years ago.

David

But that front panel was *dark*. You needed the full brightness of the lamps (#47 IIRC) to be able to read the frequency dial. And others were to tell you when you were receiving stereo and other such things.

I guess that half-power would be sufficient -- *if* I turned out the room lights first. :-)

Enjoy, DoN.

Actually the bulbs are non linear so it would be closer to 70%, and the bulbs would probably last the lifetime of the equipment. Then again, you could have used pairs at each location with the diodes and get a little bit more brightness, and longer life.

People who restore old radios with a tapped filament on the rectifier use a diode and a 9.1 volt zener to protect the filament at turn on. The zener passes the excess current, until the filaments have warmed up. BTW, the modification was my idea, and it took a long time to convince the parts changers that they couldn't use a 6 V zener.

I just wanna videotape the results when some body puts an ad in the Newspaper: Older AR-15, fully functional, loaded, modified by a professional builder.

Heh. I like it. I wonder if any of the electronics wizards could come up with terms that could apply either way, just to confuse them. I bet some audiophools could come up with something that'd make it sound like you're talking about an assault weapon. ;-)

Cheers! Rich

7.1 Channels, DVI-D and HDMI out, optical out, analog out, high s/n. 1080p full HD on both display channels, 8GB RAM, 1TB, GB Enet, and the case has been made properly conductive along its edges, and properly does the EMI/Faraday cage seal-up-the-noise regimen. Takes a week to build and configure with XP Pro, and Ubuntu, and XBMC for both linux and Windows.

For about $1300 you can haveone too.

BTW, there are hundreds of free "FM" stations online.

This thing integrates EVERYTHING.

XBMC rules.

Beige Furnace enamel, meant to be baked on, with a little carbon black added to tone it down more toward neutral gray.