Cross Shafts - First Time Home Builder

Eldon Cangas · Post by **Eldon Cangas** » 18 Sep 2009 3:51 am

I've seen square, round and hexagonal. Which is better? I can see square or hex being the best for bell crank mounting but a bit of a bear to mount it in bearings at the ends. (that was awful!). Whereas I can see slippage on the round shafts.

Any thoughts would be appretiated. Thanks.

Eldon

Bent Romnes · Post by **Bent Romnes** » 18 Sep 2009 7:39 am

Eldon,
To me it looks like square shafts are in the majority today. A few, like Mullen, use hex shafts. I love the ease with which they mount their bell cranks securely with one set screw But it takes fancy equipment to make a hex hole in a bell crank.

Square is the overall winner on modern steels because they are simplest to obtain and make.
All you need is to round each end of the cross shaft in order to mount them in sleeves or bearings.

With round shafts you have the added difficulty of changing bell cranks around when adding pulls or re-setting a copedent.

Bent Romnes · Post by **Bent Romnes** » 18 Sep 2009 9:24 am

Georg, fine tuned throw is obtained by having enough holes in your bell crank, and taking pains to level at least six holes in the crank to the six holes in the raise and lower bars. That's why I have started to favor the 14-hole Emmons bell cranks. That way, there will always be a hole that fits

I believe it is best to keep the bell crank as close to vertical as possible, or that the crank ends up vertical at the end of its throw.

Bent Romnes · Post by **Bent Romnes** » 18 Sep 2009 11:09 am

Yes, Georg...but send me an email about it.
Eldon asked a specific question that he deserves an answer to.
You and I getting into a different realm of cross rod/bell crank that is not favorable to Eldon's purpose.

Others...please give your opinions for Eldon.

Bill Ford · Post by **Bill Ford** » 19 Sep 2009 4:52 am

I agree with Bent on the square shafts for ease of setup change, but when is the last time you changed your setup? On my red guitar,2002,changed from Day to Emmons, on my MSA, when I got it,(about four years ago)I changed it from a uni to ext E9 to match red. As far as the vertical position, you could get int a never ending geometry debate on that one.

BTW..there is a tool to cut the round bearing surface on the end of the square shaft, can be used in a drill press.
Edited to say...Change???? I'm still trying to learn my original setup !!!!!!!!!
BF

Eldon Cangas · Post by **Eldon Cangas** » 19 Sep 2009 5:01 am

Thanks Guys!

Now Bill, tell me more about this tool that mounts in a drill press and cuts the bearing surface on the square rod. While we are at it what material are the cross shafts made of.

Thanks! Eldon

Jim Palenscar · Post by **Jim Palenscar** » 19 Sep 2009 5:46 am

Actually the bearing surfaces on a square cross shaft are made in a lathe and the material is most commonly stainless steel. A drill press is designed to go up and down and do not like the sideways motion that cutting a bearing surface requires. As an aside, there are square to round adapters available that enable one to use a "square peg in a round hole".

Bobby Burns · Post by **Bobby Burns** » 19 Sep 2009 6:04 am

I remember some youtube videos of Eddie Falawkwa cutting the end of square shafts with a tool that chucked up in a drill press. The tool tuned, and the part was stationary, so all the pressure was down.

I think for the first time builder, round shafts are easier, and it's a whole lot easier to make bellcranks with a round hole. Just find some hot rolled steel, cut it to length and quit worrying about it. All you really need is a hacksaw and a file, and a drill. The shaft is steel, the bellcrank is aluminum. If you are concerned about the bellcrank slipping, file, grind or mill a flat to seat your set screw against.
Use whatever tools you have and figure out how to make it work. It ain't that complicated a machine, and it ain't going to the moon. No matter how you do it, your going to redo it a few times, and fiddle with it a lot before it suits you, if it's your first one. You will learn a lot in the process.
Listen to everyone who has played or built a steel. Look at as many old and new designs as you can. Figure out how they work, decide what you think is a good idea, or a bad one. Decide what is really necessary, and what is just extra work and expense. Remember, it's a musical instrument first, a machine second. It has to sound and look good too.
The most important thing for the first time builder to do, is just build Something. There will be things you thought would be a big deal that are not, and things you never thought about that are. Every body likes different things. You will make better decisions on the second one, if at least some of you design is based on your own thoughts and opinions and experience, instead of just basing them on other folks thoughts and opinions.

Bill Ford · Post by **Bill Ford** » 19 Sep 2009 6:20 am

Bobby Burns wrote:I remember some youtube videos of Eddie Falawkwa cutting the end of square shafts with a tool that chucked up in a drill press. The tool tuned, and the part was stationary, so all the pressure was down.[/i]

Eldon, This is the tool that I was referring to, if you have access to a lathe,there is a simple jig you can make to use a 3 jaw chuck to turn a round bearing surface on a square shaft. I can post a drawing if someone is interested.

Bill

Bobby Burns · Post by **Bobby Burns** » 19 Sep 2009 6:25 am

Bill, by all means post a picture.

Bill Ford · Post by **Bill Ford** » 19 Sep 2009 7:02 am

Please excuse the crudeness of my drawing ability. Measure your square stock,point to point (dim "A")start with a 1" long piece of round stock, center drill/bore to this size, the outside dia. needs to be large enough to have at least a 1/8" wall thickness when finished, cut a 1/8" slot end to end so the collar will collapse enough to hold firmly. The bore should be a snug fit when the square stock is inserted, place the shaft into the collar, and place in 3 jaw chuck as pictured....Bill

Changed wall thickness 1/8"

Bill Hatcher · Post by **Bill Hatcher** » 19 Sep 2009 7:03 am

If you are never going to change the set up then round is fine and easy.

Square makes it easy to change the cranks when you want to change a pull.

Martin Weenick · Post by **Martin Weenick** » 19 Sep 2009 7:20 am

The cutter you describe is an "anular cutter" I use a 11/16 O.D. cutter which gives me a little less than 5/16 O.D. on the end of the shaft. They are about $30.00 and you can buy them at Enco, or any other tool supply. They come in two lengths, one and two inches. Get the one that is one inch long. You will need a chuck capacity of 3/4 inches to chuck it up. Martin.

Bent Romnes · Post by **Bent Romnes** » 19 Sep 2009 7:21 am

Bobby, lots of wisdom in your post. Bobby covered everything and there is nothing I can add to that.

I just wanted to describe how Eddie does his rounds...

He uses a hollow end mill that he has mounted in a custom made holder, in the drill press. First, he has a round-over type tool in one drill press, where he just starts the round on the shaft. Not sure what this tool looks like; could be a hollow mill of a slightly larger diameter.
Then, when he goes to cut the round in the second drill press, he has the shaft mounted perfectly vertical and brings the end mill down over the shaft after giving the shaft a liberal dose of grease. Ed's cross shafts are 5/16" and made of keystock type steel. Works good for ole Eddie....

Martin Weenick · Post by **Martin Weenick** » 19 Sep 2009 7:41 am

Here it is, Martin.

Bent Romnes · Post by **Bent Romnes** » 19 Sep 2009 9:08 am

There it is, Thanks Martin. Of course you do it in the mill which is better than Eddies drill press set-up.
That's a great vise you have also. Can't wait till I win the lottery and can buy all these goodies

Martin Weenick · Post by **Martin Weenick** » 19 Sep 2009 9:48 am

Bent, thats not a vise, it's called a 5-C collet holder. Cost - $39.00. You can get square or round, or hex 5-C collets for about $8.00 each. I just clamp the 5-C holder in my mill vise rather than bolt it down to the mill table. It takes about 10 minutes to make a full set of cross shafts. Martin.

Bent Romnes · Post by **Bent Romnes** » 19 Sep 2009 11:02 am

Sweet, Martin. One of these days...hopefully.
Thanks for posting this.

Chris Lucker · Post by **Chris Lucker** » 19 Sep 2009 12:02 pm

That is the same internal end milling cutter used to cut the round ferrule station on the end of a hexagonal bamboo fly rod section.

Pat Comeau · Post by **Pat Comeau** » 19 Sep 2009 4:45 pm

Is there a major difference between materials like...stainless, steel or aluminum for cross shafts?
or is it just for looks with stainless steel?.

i build my last steel with aluminum 3/8 rod and i'm now working on my next 2 steel projects and i'm gonna go with round shaft cause it's easy to make the shafts and bellcranks.

Bent Romnes · Post by **Bent Romnes** » 19 Sep 2009 6:25 pm

Pat, the major difference is the hardness of the material. The harder it is, the harder it machines.
Then you have the weight factor. That's why a lot of aluminum is used in steel guitars.

Chris Lucker · Post by **Chris Lucker** » 19 Sep 2009 6:31 pm

Also, the harder the metal, the harder it is for set screws to bite.

Remember to use cupped set screws.

Pat Comeau · Post by **Pat Comeau** » 19 Sep 2009 6:31 pm

Hi bent,

thanks for the anwser

...but that's not what i'm asking, maybe i should of said...is there a difference in tone with different materials.?