My band saw broke!!

[GlennW]

I'm sort of leaning toward holding it between soft jaws and the live center as well, for the simple reason that lathe dogs don't really appeal to me at the speeds at which I like to turn stuff and I don't like to back it down unless I really have to.

I'll decide which way to go this evening when it's time to make more chips.

My income is based on my two hands, so it's hard to overlook time spent on these little fun projects when I have two buildings full of work waiting for me!

[Bill Shields]

all the more reason to have a reliable band saw available to you ASAP !

[whateg0]

all the more reason to have a reliable band saw available to you ASAP !

Or buy a spare of everything!

[BadDog]

Nice work (as always).

Mine hasn't failed yet, but sounds like the design makes it likely at some point. I wonder if that was intended to be some sort of torque limiting fuse?

[Bill Shields]

not hardly....just a design oversight....torque limiting (mechanical) is rarely done by 'twist off'...shear keys yes...sharp corner failures...???

there is literally no way of knowing how long it would run without failing without a lot of testing...

and why would they bother?

[BadDog]

I may be misinformed, but axle shafts sometimes feature a necked down portion that I've been lead to believe is specifically for that purpose. Particularly in front shafts. Maybe a myth, but I've heard that argument put forward for other things as well. However, these instances are "neck down" areas without sharp corners, so maybe that's the key difference.

I'm not an engineer, but it is really hard for me to believe that a company like Roll-In would not be aware of (or careless about) the issues caused by sharp stress risers on cast shafts.

That's just the voice in my head, but that thought process is what led to my post.

[RSG]

Yea, I didn't want to have to go through this again in 40 years. Once is enough.

[GlennW]

Another hour into it...

Centers won since it was quicker to set up. I didn't feel like noodling with soft jaws, although I made a pile a while back.

Grooved it.

Turned it and then threaded it. The first facet (small end) wanted to sing, so it took me a minute o find a happy feed and speed which was faster and faster to get a respectable finish!

Ready for the grinder. I left .007" to .010", which is a lot, but I'd rather have to grind a little excess than hard chrome it!

I'll need to make a dog to drive the small end...

[BadDog]

As always, very nice.

But I'm a bit confused, I must be missing something. With just the material alone it's (presumably) way stronger than original and likely a moot point, but it looks like you put the extra (not quite?) square corner grooves back in that I thought you were saying weren't required and led to the breakage.

[GlennW]

Not square corners. .025" radius. Might even be .030". I'd have to look.

[BadDog]

I misunderstood and thought you were going to eliminate the groove as not necessary, but now I see it was the sharp (tiny fillet) corners you were talking about. Thanks for clearing it up.

[GlennW]

Grooved with this.

Kennametal Multidirectional Tool. It will turn, face, groove, and part. It is quite stout as I have turned with it to full depth.