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Author Topic: How best to polish brass endbells?  (Read 5030 times)

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Offline Jim R.

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How best to polish brass endbells?
« on: August 20, 2013, 05:31:13 AM »
What is the best way to polish brass endbells and to maintain the polish?  Which grades of polish shoud one use -- for instance, is just red and blue ok for this or do they need something a bit more aggressive to start?

Thanks,

Jim
Jim Rebman -- recovering audiophile

Equitech balanced power; uRendu, USB processor -> Musette DAC -> 5670 tube buffer -> Finale Audio F138 FFX -> Cain and Cain Abbys near-field).

s.e.x. 2.1 under construction.  Want list: Stereomour II

All ICs homemade (speaker and power next)

Offline Paul Birkeland

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Re: How best to polish brass endbells?
« Reply #1 on: August 20, 2013, 05:40:09 AM »
I would polish the crap out of them, then clean them aggressively with some pretty nasty chemicals, then powder coat.

Powder coating brass (clear) can be pretty tricky, as the increased heat can spurn oxidation.  I would pay to have a shop do that.

For the added cost, you'll get 20+ years of maintenance free finish.

-PB
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Offline Doc B.

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Re: How best to polish brass endbells?
« Reply #2 on: August 20, 2013, 06:40:46 AM »
Lacquer is a lot easier and holds up quite well. IIRC I used maybe tripoli polish to start and finished with rouge on a wheel. The real booger is getting in the nooks and crannies around the mounting tabs. A Dremel with a polishing tip helps with that. Clean them really well with acetone and shoot a few coats of lacquer.
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Offline Jim R.

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Re: How best to polish brass endbells?
« Reply #3 on: August 20, 2013, 07:00:42 AM »
Dan,

Yes, plan to use the dremel for the tight spots.  I also have some of that nice water base metal lacquer from  Caswell that has worked nicely on other metals.
Thanks,

Jim
Jim Rebman -- recovering audiophile

Equitech balanced power; uRendu, USB processor -> Musette DAC -> 5670 tube buffer -> Finale Audio F138 FFX -> Cain and Cain Abbys near-field).

s.e.x. 2.1 under construction.  Want list: Stereomour II

All ICs homemade (speaker and power next)

Offline Jim R.

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Re: How best to polish brass endbells?
« Reply #4 on: August 20, 2013, 10:11:46 AM »
Or I could gold plate them. Hmmmm. Over nickel first, of course.

-- Jim
Jim Rebman -- recovering audiophile

Equitech balanced power; uRendu, USB processor -> Musette DAC -> 5670 tube buffer -> Finale Audio F138 FFX -> Cain and Cain Abbys near-field).

s.e.x. 2.1 under construction.  Want list: Stereomour II

All ICs homemade (speaker and power next)

Offline adamct

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Re: How best to polish brass endbells?
« Reply #5 on: August 20, 2013, 10:26:44 AM »
Personally I would go for a diamond encrusted end bell...

Offline Jim R.

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Re: How best to polish brass endbells?
« Reply #6 on: August 20, 2013, 12:02:46 PM »
Adam,

Is that really necessary?  You've made it very clear many times over that you think most of this stuff is BS because you can't tell a difference.  That is probably the case as humans have anything but equal abilities to discern  differences in tone, pitch, rythm, etc, and I totally believe that you hear what you hear, but you really have no right to challenge anybody else's listening abilities and even less right to make value judgements for others -- that is a very personal choice for all of us, what is worth it and what isn't, and the real answers only come from lots of experience.

Admittedly the gold plating is almost totally aesthetic, but that is my own personal value and not something I'm telling everybody else what to do, nor do I need their approval.  The upside of gold plating is nearly zero maintenance, it has an aesthetic appeal to many, and why shouldn't a world class amp look like one?, and finally, it's probably nowhere near expensive to do the plating oneself than you might think.

C'mon, this is a hobby -- you enjoy it your way, and I'll enjoy it mine, and if aesthetics and industrial design happen to be important to me, who cares?

Listen and let listen.  Build and let Build.
Jim Rebman -- recovering audiophile

Equitech balanced power; uRendu, USB processor -> Musette DAC -> 5670 tube buffer -> Finale Audio F138 FFX -> Cain and Cain Abbys near-field).

s.e.x. 2.1 under construction.  Want list: Stereomour II

All ICs homemade (speaker and power next)

Offline Doc B.

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Re: How best to polish brass endbells?
« Reply #7 on: August 20, 2013, 12:08:00 PM »
Hey Jim,

For what it's worth:
I'm not sure of the preferred layering over brass, but I know that with inexpensive watch cases which I think are maybe nickel based the first plating layer is copper, then nickel then gold. Don't know that brass needs the copper layer, which is a filler for dings and scratches as much as anything.
Dan "Doc B." Schmalle
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Offline Grainger49

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Re: How best to polish brass endbells?
« Reply #8 on: August 20, 2013, 12:08:47 PM »
I used the Dremel tool and Meguiar's all metal polish.  Then washed them with several cleaners and shot them with lacquer.  That was years ago and they are bright and shiny today.

Offline adamct

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Re: How best to polish brass endbells?
« Reply #9 on: August 20, 2013, 12:18:28 PM »
Whoa, very, very sorry if I've offended.

First, I actually thought you were joking with your comment about gold plating, so I thought I was just adding to the joke.

Second, when it comes to differences in sound (I assume you are referring to my recent comments on tube rolling), I have given people advice on whether I consider tube-rolling a cost-effective upgrade. But I have also made it clear that I understand that some people enjoy tube-rolling, and that I don't have any objections to it. It is, as you say, a totally personal thing.

Third, I am no opponent of purely cosmetic changes or changes that have limited audible effect. The most explicit example of this is the fact that I don't think headphone cables make any audible difference whatsoever, yet I have probably spent over $1,000 on custom cables for purely aethetic reasons. For that matter I have installed upgraded volume pots / stepped attenuators and film caps in my Bottlehead projects, even though I am not even remotely certain that I can objectively discern the difference they make. Finally, notwithstanding my feelings about the limited difference that tube rolling makes to a Speedballed Crack, I have dozens and dozens of tubes at home, and recently bought 3 more. My comments on various changes go to the question of whether they are cost-effective changes for someone looking for a noticeable change in sound, not whether they are something that nobody should do if they want to. In particular, there are many people who are put off buying a Crack, or who cannot enjoy their stock Crack, because they think they need to install all sorts of upgrades in order to have something that sounds even remotely acceptable. I'm a big fan of tweaking, because I enjoy the process, but I don't want to contribute to anxiety and feelings of insufficiency for people who have a limited budget. I'm fortunate to be able to spend a fair amount of money on this hobby, but I try to keep things in perspective for others who don't have the same resources. Which isn't to say that anyone who DOES have the resources shouldn't tweak to their heart's content as much as, and in whatever form, they please.

In any case, I wasn't trying to judge your choice. I wasn't aware of the practical benefits of gold plating, and as I said, I didn't even realize you were serious. Maybe that is offensive in and of itself, but I can't help what I don't know.

Besides, a diamond-encrusted bell would look damn cool...and talk about zero maintenance!

 ;D

With sincere apologies,
Adam

Offline adamct

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Re: How best to polish brass endbells?
« Reply #10 on: August 20, 2013, 12:36:40 PM »
And just to follow up with a few more examples:

- I was planning on modding the crossovers in my speakers...until I found out that they were already upgraded by the previous owner.

- I own not one, but two, GEC 6AS7Gs for my Crack, even though I don't think they sound noticeably better than any other 6080 or 6AS7G or 5998, other than the fact that they are quiet (no noise). And I also have 5 5998s, a Bendix 6080 with graphite plates and other tubes that I acquired at considerable expense.

- I own HiFiMAN HE-6s, Sennheiser HD800s, HD600s (two pairs) and Amperiors, Denon D7000s, Ultrasone Signature Pros and Pro 2900s, Darth Beyers, Beyerdynamic DT990s, AKG K1000s and K240Ms, Kenwood KH-K1000s, V-Moda M100s and German Maestro GMP 8.300 D. I have owned and sold dozens and dozens of other headphones.

- I have the following headphone amps: Bottlehead Crack, S.E.X. (unbuilt), Smack (unbuilt), Schiit Mjolnir, Violectric V181, AMB M^3 (two of them), Audio-Gd Roc SA, Decware Taboo (with Bottlehead Quickie), Little Dot Mk VI+, Brocksieper Earmax, Eddie Current Laconic EC-01, and any number of portable amps. I also have boards for a Kevin Gilmore Dynamite (balanced Dynahi), KGSSHV, Singlepower Squarewave and Krell KSA-5 on the way. I have owned and sold dozens and dozens of other headphone amps.

- I won't even get into how many DACs, cables and other accessories I have.

Does any of this sound like someone who doesn't believe in subtle differences between gear? Note that the gear above is the gear I have chosen to KEEP (at least for the time being), after owning, trying and selling tons of other gear. I'm a fan of tweaking, and I'm obviously not going to pass judgment on how much anyone else spends on this hobby. Again, my comments on tube rolling (I'm not sure I've really commented on anything else other than saying I'm not sure the $100 I spent on my TKD potentiometer for my Crack was worthwhile - and even there I said that the TKD was perfectly fine, I just didn't think it was worth $75 more than a $25 VALab stepped attenuator) were only intended to help those with limited budgets and/or those who were looking for the biggest audible bang for their buck. I continue to believe that getting better (or even just different) headphones is a better use of money than most tweaks, but that obviously hasn't stopped me from tweaking, too.

Regards,
Adam

Offline Jim R.

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Re: How best to polish brass endbells?
« Reply #11 on: August 20, 2013, 12:41:22 PM »
Dan,

I think you're right but I also think it depends on the condition of the surface to be plated and on the particular gold plating formulation.  I think caswell recommends the flash copper first layer for most situations and both of their gold formulations.

Grainger, another good data point.

Adam, sorry, and I don't even know what tube rolling thread you're talking about, but my point is that you consider tube rolling to be a subtle change and recommend people do it if that's what they want, on the other hand other people have thought the Crack to be a completely different animal with tube rolling.  That's the whole point.  Value judgements are each individual's call.  I've used some of those boutique caps that most people think a ridiculous expense, but I've yet to be let down by them except in one amp and it was a synergy thing and when replaced by a much less expensive cap made the amp far better sounding to me.  No problem, the spare caps will find a new home sooner or later.  I think it's more like comments that you can tell somebody 10,000 other things worth upgrading over usb cables, and that's I'm certain what you think and what you experienced, but that's not universal by any means nor is how much to spend on a usb cable.  I myself have found great benefit in using a high grade usb cable, but I've sent back a couple of the uber expensive ones because they just didn't sound much better to me.  Do I care if somebody with more disposable income than I spends $4k on a usb cable? No, not worth it to me, but for whatever reason, it's probably worth it to that person or they would have dumped it.  I still think something like the wireworld bsic starlight red usb cable is a fantastic cable and it's relatively cheap for the performance improvement I hear.

So, no harm, no foul... back to plating and polishing.
..

BTW folks, the usb cable example was just that and I really don't and won't get into a discussion of usb cables (or tube rolling) here.  I avoid those hot button arguments like the plague nowadays.

Back to your regularly scheduled thread...

Jim
Jim Rebman -- recovering audiophile

Equitech balanced power; uRendu, USB processor -> Musette DAC -> 5670 tube buffer -> Finale Audio F138 FFX -> Cain and Cain Abbys near-field).

s.e.x. 2.1 under construction.  Want list: Stereomour II

All ICs homemade (speaker and power next)

Offline adamct

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Re: How best to polish brass endbells?
« Reply #12 on: August 20, 2013, 12:53:09 PM »
Jim,

Point taken. But I'll just make one more comment and then we can put this to bed: it is valuable to know what other people find to be worthwhile, but it is also valuable to know what other people find is NOT worthwhile. Otherwise all we're left with is a sea of positive reviews with no way of putting them in relation to each other. You think the Wireworld basic Starlight red usb cable is a fantastic cable, but I would also be interested in knowing what cables you rejected as not worth the money, for example [this is just an example: I respect that you don't want to get dragged into a USB cable discussion]. We can't just all sit around and recommend that everyone buy all the time. For people with limited budgets, advice on what not to buy can be just as valuable, if not more so.

Finally, my opinion (like anyone else's) is just a data point. It is what one person believes. Nobody should read what I write and go out and copy my setup or take my opinion as gospel. But the fact that an individual data point isn't an absolute law doesn't mean it isn't worthwhile. Eventually, 100 data points that point in the same direction start to have some weight behind them. It still doesn't make those 100 data points correct, but it becomes harder to ignore them. I would certainly be worse off if nobody here voiced their opinion on what they thought of various bits of gear and their relative value.

Best regards,
Adam


Offline adamct

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Re: How best to polish brass endbells?
« Reply #13 on: August 20, 2013, 01:47:18 PM »
And to bring things back on topic, can anyone tell me what the stock end bells are made of and whether painting, lacquering or other treatment is necessary for longevity (as opposed to cosmetics)? Will the stock end bell actually corrode and fall apart over the (very) long term, or just become discolored?

Thanks,
Adam

Offline Doc B.

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Re: How best to polish brass endbells?
« Reply #14 on: August 20, 2013, 01:58:37 PM »
The stock bell ends are steel. They need some kind of coating to keep from rusting. How much they will rust depends upon the humidity of the environment where they live. We usually just clean them with naptha or acetone, buff them with some fine steel wool and spray them with a clear coat. Rattle can paint or powder coating works great if you thoroughly clean them first to remove any oils.
Dan "Doc B." Schmalle
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Bottlehead Corp.