aluminum drum roller inductor? - Page 1
Forum section: electronics / rf-microwave

author: coppercone2
author_rank: Super Contributor
timestamp: October 15, 2023, 02:30:00 am
content: ***thread is irrelevant because there was a bound shaft that caused a gear to break and its in the trash now. all that shit super fused together.. flame, bearing pullers, etc did not work. I never seen stuff fused this bad, the gear snapped off at the base rather then coming off lol. i bet the inductor winding would break on first use, given how everything else in that system was behaving.this thing, had a siezed gear under almost ever snap ring. And one of them even had a DIY pin installed because someone did not wanna bother with a set screw. The brass must have like welded itself to the steel or something. Really terrible. Maybe it would be OK if they used a brass shaft, but this combo is bindmageddon.Every snap ring broke on disassembly too. i wonder WTF happened to this thing LOL.Maybe if you machined full-contact bearing pullers for every gear, you could get 90% off. But it would be some crazy shit, the clearance under the bound gear 'extension' structure was maybe 0.5mm, and mounted to bakelite. I seriously think almost every gear here would need a custom puller to possibly disassemble this seized POS without cracking. Or you would have to drill holes for anchor pins on the gears so you can get enough leverage. and some of the gears were baklelite too, when i saw that an alarm went off in my head, the counterparts I have seen to these variometers had all metal/ceramic construction (soviet).I highly recommend paying as little as possible for roller inductors, they are not serviceable. The soviet ones are better quality it seems like (rare). I guess they liked coils more.I see some evidence of silver soldering on the gears, so I assume maybe, they induction or whatever soldered these things, and assembled certain structures while hot, then put a snap ring on it anyway... IDK why else this would be so hard to diassemble. But they used snap rings, and like piles of carefuly chosen shim washers to position everything, so that again makes me think its some kind of post assembly binding process. There is a mix of copper alloy, copper, brass, bakelite, steel. I wonder if its some kind of electrochemical reaction that bound this crap up.I thought 2 hours to diassemble, clean/polish and reassemble the whole mechanism. After 4 hours I had one gear removed after tons of figuring about prying and shit*******I have a roller inductor that has a aluminum drum for shorting the coil as it unwraps.It looks like plain aluminum. No Alodine or whatever. Its a bit nasty.How should I go about cleaning it? Is chemical polishing OK, or does that leave extra oxidation on the end that inhibits electrical conductivity? Should it just be a mechanical polish?I don't want to alodine it because its like a moving part, I have a feeling it will get messy since its a gel.What surface finish do I go for to get optimum conductivity ?I wanted to use aluminum polishing paste, because its very effective. But since it has some chemicals in it, I am wondering if maybe the conductivity would be sub par.Maybe some kind of mild acid wash after full cleaning and then recleaning it with distilled water to strip any residual oxide post polishing?or maybe clear alodine 1001 can be used

author: coppercone2
author_rank: Super Contributor
timestamp: October 15, 2023, 05:13:48 am
content: taking it apart the top and bottom sections do look like they might have alodine on em. Like faint coating. I think I will use 1001 on it.My procedure is gonna be polish, electroclean, alumiprep and then alodine 1001

author: coppercone2
author_rank: Super Contributor
timestamp: October 16, 2023, 10:53:56 pm
content: got one with a brass drum. time for round 2I was never gonna be satisfied with the aluminum shorting drum anyway. I think my stomach turned side ways trying to figure out the alodine classes and durability etc. From what I understand it would be unstable. I guess capacitance is doing the work but seriously having some kinda gel film as part of the transmitter circuit is just ridiculous, and so is aluminum oxide growth, etc. that aluminum drum one was built by desperate men. The spec is like "when fresh".I don't consider produce to be an acceptable circuit element in a transmitter. Sure the shielding/housing yeah.. that is kind of like clothing, I expect it to be a little wonky, but it should not be a major element in a totally rupe goldberg circuit with motors and stuff.I imagine the equivalent circuit having like a potato or some kind of tuber in it for the aluminum drum aging resistance.the monthly drift of Q depends on humidity and is non reversible ?The PRLC circuit, potato resistance, inductance and capacitance. Do these drums store better in a root cellar ? that is how you know the MIC is involved, there is a freshness specification for a non load bearing aluminum pipe. We don't think major kong is going to be flying around for too long, don't worry about it. And it probobly had some restrictions on it, like ' [ x ] NG ' (no guam) . Did the plane happen to fly over the pacific? schedule it for the next air to air missile test

author: coppercone2
author_rank: Super Contributor
timestamp: October 20, 2023, 07:42:12 pm
content: the new one I got is really nice.Things that might show a higher quality big RF component1) look for the bakelite/whatever that looks more like 'french polished' dark wood, not the lighter colors (i.e. no 'pine' like colors of bakelite, I am associating this with cheap/ancient )2) look for acrylic pieces3) look for brass pieces (i.e. random chassis elements)4) look for more standard components like standoffs (more modern to have a threaded standoff then everything custom)5) look for darker color bakelite gears (the ones that have the cardboard color seem to be indicative of the 'budget' versionIf it looks like a cheap wood box (even if its bakelite, I mean like a cheap wood) then chances are the whole thing is built like cheap shit!I feel like I went from IKEA to artisan table here.Does anyone else notice the trend of objects built with nice looking french bakelite being a higher quality then objects built with cardboard looking bakelite? I mean its a pretty big guess to just assume quality by the color of the material, but I am starting to be convinced the engineer that decided 'standard cardboard look is OK' is NOT gonna be the one that has something you want after 60+ years.Like this one has engineering screws, standoffs, brass, normal spring clips, etc

author: A.Z.
author_rank: Super Contributor
timestamp: October 20, 2023, 08:20:16 pm
content: http://ur4ll.net/#rol

author: coppercone2
author_rank: Super Contributor
timestamp: October 20, 2023, 08:29:18 pm
content: the prices are good on that stuff for the quality its at. IMO fair pricingWhen the soviet government is in charge, you get good transmitter parts lol. Just need to wait until the state collapses before you get your hands on themonly bad part I see is some of the wires. Replace that with western wire. The older western radio parts typically have high quality teflon insulation, but thats about all that is high quality on them IMO.

author: TimFox
author_rank: Super Contributor
timestamp: October 20, 2023, 09:10:57 pm
content: Quote from: coppercone2 on October 20, 2023, 07:42:12 pmSee my comments to another threadhttps://www.eevblog.com/forum/mechanical-engineering/how-to-press-fit-brass-bearing-sleeve-into-bakelite/msg5119257/#msg5119257about the difference between BakeliteTMand other composite materials. Real BakeliteTMis shiny enough that jewelry has been made from it, but it is kind of brittle for many applications.McMaster Carr lists the composites (including G-10 glass/epoxy) under the term "Garolite".

author: A.Z.
author_rank: Super Contributor
timestamp: October 21, 2023, 07:31:00 pm
content: Quote from: coppercone2 on October 20, 2023, 08:29:18 pmthe only "issue" (let's call it so) I see there is that, if I'm not wrong, that stuff is shipped from Ukraine, and given the current situation...Otherwise, I bought stuff from him, in a past, and had no issues, and tubes (check them) and variable caps, are good

author: coppercone2
author_rank: Super Contributor
timestamp: October 29, 2023, 04:46:30 am
content: well I got around to dismantling this one and everything is coming apart properly. IDK wtf was with the other one. Like holy shit something was wrong with that one.all those god damn shafts like were welded together or something jfc.this one had the snap rings come off nicely, the gears pulled out with bearly any effort. the other one literarly everything was fused or brittle. I wonder if it underwent some kind of transformation under the influence of the aircraft or possibly radio waves (there was no gross signs of corrosion other then blackened brass).Could a EM field do this?

author: coppercone2
author_rank: Super Contributor
timestamp: October 29, 2023, 10:54:10 pm
content: ok it spent a while in the ultrasonic, and I wound it on both bobbins when it was under alnox.Then I polished the drum with never dull, and also dragged the silver coil through neverdull.Then I gave it another bath in alnox. then I did a strong rinse, and a final ultrasonic bath in distilled water, rolling it between bobbins a few times.then I dry off the drum and apply deoxit with a towel. Then I wrapped the coil up through a deoxit soaked cloth and applied grease to the shaft holders and gears. it looks alot better. It was massively filthy with lots of hairs and shit inside of the gears. Now ima let it heat up in a oven thats been heated and turned off so it can dry off gently.i also removed the ferrite rod from inside of the ceramic drum and the motor/syncrho before doing this, so they can get seperate treatment because those are delicate. I think I read ferrite is bad to soak also.