uncle.fogey - Posted - 04/17/2012:  16:21:04

Back in the 60s, when I started making banjos, I designed and built a guitar as my Industrial Design thesis at Pratt.  In those days, there was NO information available about how to do that - hard to understand in these days of information overload. I read about how to make violins and talked to people in New York who were making guitars, like John D’Angelico and William Del Pilar.

What I realized is that banjos are more metal than wood - more of a machine than a “musical instrument” I remember joking about that at the time.



The point is that you have to learn how to be a competent metal worker or you will be a slave to the companies that make metal parts.

FORTUNATELY, most banjo parts are made of some alloy of brass, which is easy to deal with.



This is going to be a long thread, because here are all the metal parts you have to make - not counting hooks and nuts: I might break it into sections - metal working, bracket band, tone ring, tension hoop.





Banjo brass parts are rarely wider than 1”, which makes it easier. You have to have some kind of bending tool that can bend strips and hoops of metal into relatively accurate circles.

The Harbor Freight ring roller, generally lacking in quality, is the best thing you’ll find, and you’ll have to modify the rollers:





Once you can roll things into accurate circles ( you can do it by hand, but it’s time consuming) you need to learn how to silver solder or braze metal parts.  Regular solder won’t work, and stuff that’s called “silver solder” is often a joke. You are operating in the 1100 - 1500F temperature range - be careful - count how many times I say “be careful” Don’t ask me why I say that.



You need to use actual “silver brazing rods”  The silver content reduces the flow temperature, but raises the cost BIG TIME.

Make sure it doesn’t have cadmium in the alloy - be careful:





For a brazing station, it has to be fireproof and well ventilated with refractory slabs to use as a base for brazing - these have to be coated with “kiln wash” - be careful:



It’s better to do it outside if weather permits - you don’t want to breathe this s***:

You need a “pickling” solution  to clean the scale off the brazed parts, and the safest one is called “Sparex” - it’s an acid - be careful:





SO,  You clean the parts, brush flux on the mating surfaces, heat it up with a torch (mapp gas will work for banjo parts), and flow the solder into the joint:





The joint gets all black and oxidized from the heat and flux - this is called scale.

You dip it into the pickle and it gets clean and pink, with a copper flash, which I’ll discuss later - when you clean it up, you can barely see the joint:





The joint is practically as strong as the metal itself, and equally ductile (which is a result of the quenching in the Sparex) - here I am bending the sample with no problem:



Next - on to the real stuff.

 

Grum - Posted - 04/17/2012:  16:44:33

More! More! More!

SWCooper - Posted - 04/17/2012:  16:53:13

Whoa.

george pereda - Posted - 04/17/2012:  17:14:55

wow- I always dreamt about doing this stuff-----All I do is play the banjo--which is ok-too

HolyGrass - Posted - 04/17/2012:  17:26:12

YES!

i'm probably years from even attempting something like this, but it sure is great to learn about. thanks again; even more excited about the book now

Waltj - Posted - 04/17/2012:  17:33:37

This is opening another thing to learn and do.  Thanks again.

Walt

Edited by - Waltj on 04/17/2012 17:35:44

Waltj - Posted - 04/17/2012:  17:49:04

Ken, I assume you have a source for the brass. What is the cost of the raw brass typically versus buying parts already made. I assume you would cut the flange from a large square of brass. Thanks

Walt

uncle.fogey - Posted - 04/17/2012:  18:22:25

Just as an example - to make a tension hoop - 3/16" x 5/8" (Vega size) to fit an 11" diameter pot would take a 36" piece of brass,which would cost about $13.

The cheapest "ready made" ones on the internet are $37 (nickel plated). I have requested quotes from people who will nickel, plate banjo parts, and I am getting $40 for a tension hoop, which added to the $13 is $53.  $37 seems like a bargain too good to pass up.

Making your own and not nickel plating it at $13 is even more of a bargain.

Plating is a big problem, used to be easy, and frankly, it pisses me off- I don't know why these guys are so expensive - If you are making more than a few banjos, I think it's worth your while to get a Caswell plating set-up and do it yourself - screw these guys.

mcgeorgerl - Posted - 04/17/2012:  18:37:57

I often take equipment parts to a nearby plater, Leonhardt Plating on Este Ave. in Cincinnati. I think they must do some parts for Stew-Mac because I've seen banjo parts on the dock.

In a discussion with one of the managers, it seems that the majority of the actual cost to plate is due to the regulations of all of the rather nasty stuff used in the process. I recall him saying it's something like 3 out of every 5 dollars is due to chemical and hazard controls, including outrageous shipping and disposal costs. Gone are the days that the "barrels are buried out back" and the fumes go out a pipe though the roof.

uncle.fogey - Posted - 04/17/2012:  19:09:17

quote:

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Originally posted by mcgeorgerl

I often take equipment parts to a nearby plater, Leonhardt Plating on Este Ave. in Cincinnati. I think they must do some parts for Stew-Mac because I've seen banjo parts on the dock.



In a discussion with one of the managers, it seems that the majority of the actual cost to plate is due to the regulations of all of the rather nasty stuff used in the process. I recall him saying it's something like 3 out of every 5 dollars is due to chemical and hazard controls, including outrageous shipping and disposal costs. Gone are the days that the "barrels are buried out back" and the fumes go out a pipe though the roof.

 

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I am well are of that.  It's not the nickel, as much as the chrome,and nickel plating was only a step in the chrome plating processs. The motorcycle chrome plating guys of yore have all gone out of business because of the cost of disposing of their toxic waste, and that's as it should be - no complaints from me -I certainly don't want to foul my own backyard to nickel plate my tension hoops

Nonetheless, there is a huge discrepancy between $40 and the inceremental cost between $13 and $37.

I have gone through this again and again, for 3 years, searching the internet for nickel platers in my area, because I just don't want to do it myself, and it isn't rocket science, BUT  this is one of those things that I MAY just have to suck it up and do myself anyway - these guys aren't going to get any less expensive as time goes by.

I will figure out how to responsibly deal with the waste, and it's probably easier on a small scale than on a large one.

aeroweenie - Posted - 04/17/2012:  19:36:16

Great information.  I had no idea that a brazed butt joint with thin brass resulted in a joint as strong (and ductile) as the brass.

Seeders - Posted - 04/17/2012:  20:35:01

Thanks for all the work you're putting into these posts. I'm planning on making some hardware as my brother is a metal worker and has his shop right next to our woodshop. I use Rickards hardware, which I'm a big fan of, but having all the necessary tools next door I thought it would be fun to experiment a little with some different designs. What alloy of brass do you find works the best for soldering?

I'm looking forward to seeing how you go about making your resonators as this is something I'm also planning on doing soon and would like to see some various methods of doing so.

Thanks!

Seansvoice - Posted - 04/17/2012:  20:50:25

This is fascinating. Ken, according to Caswell's website April is nickel plating month. I don't know that it will ever again be gold plating month...not at current prices!

blindsniper - Posted - 04/18/2012:  00:28:02

Very informative.  Thank You Ken

Beetle_bombshell - Posted - 04/18/2012:  01:11:08

Hi Ken,  Great stuff.

In all the pictures in your current threads the 1/4 in dia brass rings are shown open ended.  ie. not silver soldered into a continuous ring. Is there a reason for this?

When I learned silver soldering 45 years ago the maxim was physically clean ( with abrasives) and chemically clean ( the hot flux). Get the job up to temperature as quickly as possible.  Most amateurs struggle to get things hot enough so it's best to arrange your refractory items to contain the heat and reflect it  back where its needed. Time spent making sure the mating items are held securely in contact is worthwhile.  Nothing worse that approaching the desired cherry red and the the whole setup collapses - cascading red hot components burning the floor and bench top.

Like a lot of things if everything  is just right it looks so easy, but be prepared to struggle the first time.

Like the rest of BHO can't wait for the rest of the series.

Richard.

ronwalker49 - Posted - 04/18/2012:  03:40:00

"you’ll have to modify the rollers:"----What do you need to do to the rollers Ken..?

uncle.fogey - Posted - 04/18/2012:  04:52:07

quote:

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Originally posted by ronwalker49

"you’ll have to modify the rollers:"----What do you need to do to the rollers Ken..?

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You have to grind the knurling off or they really mark the brass.

uncle.fogey - Posted - 04/18/2012:  05:02:51

quote:

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Originally posted by Beetle_bombshell

Hi Ken,  Great stuff.

In all the pictures in your current threads the 1/4 in dia brass rings are shown open ended.  ie. not silver soldered into a continuous ring. Is there a reason for this?

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Thanks, Richard,

I have done it both ways, and can tell no difference in the sound - it's easier not to solder the hoop.  In many of the old Vega and Fairbanks banjos, like the Whyte Laydie they did not solder the hoop. If it's the correct diameter, the hoop closes when you put the head on the banjo.

On my tone rings, the hoop is not attached to the tone ring, but is held in place by the head.

uncle.fogey - Posted - 04/18/2012:  05:08:43

quote:

---

Originally posted by Waltj

Ken, I assume you have a source for the brass. What is the cost of the raw brass typically versus buying parts already made. I assume you would cut the flange from a large square of brass. Thanks



Walt

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Walt,

I will be showing how to fabricate the parts soon. I try to have as little waste as possible.  It is quite a bit less expensive to make brass parts than to buy them already made.

I don't cut the flange from a big square.

SFI - Posted - 04/18/2012:  05:13:30

I am in the process of buffing and plating wire armrests. The armrest is a 3 piece unit. I have price quotes from $2.50 each to $.70 each. The 70 cent price could even be lower if I could  buff all 4,000 armrests and deliver them to the plater at one time. So part of the cost is the time it takes to process the order through the office. Bring 100 tension hoops and I am sure the price will drop.

I used to have a plater in Cleveland, OH that you could drop by with your small batch of banjo parts and he would do them for you as you waited & charge you a small amount in cash. Those were the days...

Thanks for taking the time to show the masses banjo building details that are not talked about often.

Bob Smakula.

uncle.fogey - Posted - 04/18/2012:  05:47:01

Thanks, Bob,

I did ship a box of them to Kentucky about a year ago, and got a good price. Unfortunately, that company no longer does nickel plating.  Since I make custom banjos, the parts aren't standardized enough for me to mass produce, and I never know what the next one will be because my designs change.  If I made 50 tension hoops with 24 notches, the next customer would want one with 28 hooks.

I have found a source that plates antique car parts, and that might work out.

I know you have started to sell raw brass tuners, which ought to be a good seller.  I wish somebody would make brass plated steel hooks & nuts.