Prop Shaft

[HB Vic]

Well this thread is going nicely.

Lets please keep the name calling to a minimum. While I understand the need to pop off on occasion, please try to make more general statements. For example: Not all machinists are brain surgeons. My monel is better than your monel. My WWII lathe will machine better than your CNC lathe. Even my shaft is harder than your shaft is ok. LOL

But lets try to keep pet references out of the equation.

[ogshotgun]

Well this thread is going nicely.

Lets please keep the name calling to a minimum. While I understand the need to pop off on occasion, please try to make more general statements. For example: Not all machinists are brain surgeons. My monel is better than your monel. My WWII lathe will machine better than your CNC lathe. Even my shaft is harder than your shaft is ok. LOL

But lets try to keep pet references out of the equation.

i wasn't calling any names and if some one is clueless well thats my opinion, but did not use any bad words

[ogshotgun]

so i asked Glenwood to send me a picture of how they cut the taper on there prop shafts ...what i got back is this please follow along

Hello there Thanks for inquiring about our prop shafts , i will try to answer your question, we used this set up for many years see attached photo
than in the last ten years we upgraded to the modern set up in the next photo Hope this answers your questions
Regards Vicky

notice the date on the brochure 1944

[ogshotgun]

Micheal,
You got your new shaft, you seem to be happy with it, why are you continuing with the rant. Why don't you just thank Bob for recommending the supplier and put your boat together.

i have my shaft and it will work fine, some guy came on here bad mouthing the Aquamet 22 and than bob started in saying his 99 cents worth and its been going since, now he says a ww1 lathe will produce the same shaft as a new high end cnc lathe will.. now aim going out of my way to prove him wrong..and he never mentioned Marine Machine i found them on my own...

[SnoC653]

i have my shaft and it will work fine, some guy came on here bad mouthing the Aquamet 22 and than bob started in saying his 99 cents worth and its been going since, now he says a ww1 lathe will produce the same shaft as a new high end cnc lathe will.. now aim going out of my way to prove him wrong..and he never mentioned Marine Machine i found them on my own...

News flash, long before there were CNC machines people were making precision parts. My grandfather was a gear maker, and was one of the finest in the country according to the people that sought him out long after he retired. When computers first came on the scene they used to get the best engineers they could find to walk them through the process so they could get the machine to do it the same way. I remember they called him out of retirement to help them make a gear for a giant shovel (used at strip mines, looked like a house on a turn table). My grandfather said they had programming engineers watching everything he did, and how he bets that somewhere there is a computer that stops and scratches it's imaginary nose before moving to the next step.

The point is, the old equipment is just as capable as the new fancy stuff with the right operator. The new stuff is faster and easier to duplicate the same part over and over. And the new stuff doesn't require the same level of skill from the operator, just from the programmer. The new stuff also repeats the same mistakes over and over if they were programmed in, or something becomes out of tolerance.

You'd be amazed at how many people can't do a simple task like turn a brake rotor because they can't grasp the concept of to big a cut or a dull bit. And when you apply it to turning a exotic metal the number of people that can't goes up drastically. And there is more to metal work than just how it looks when it is done, so I'll take GN7's advice when he says this shop knows what they are doing. I also trust people that work with these metals to school us. I know the precision that Westernaero has to meet on aircraft as well as seeing some of the great stuff he is turning out. This site is fortunate to have the people with real world experience and top notch skills.

[gn7]

Sorry Sno, I can't agree with this 100%.
But a good machinist know a whole hell of a lot more than just the machine.

I agree. But they were making some pretty high power boats, specially when they were driving all the power of a TFH thru single shaft, and
with shafts machined in full manual machines long before CNC.

CNCs are no different than computers, garbage in, garbage out. Like the man leaning against a WWI lathe, he can make it the best that is possible with the machine, or make the part useless. A programmer can fuck a piece material just a easy as yahoo on a 50 year old Logan.

I look at my AFR CNC ported heads, and my Canfields hand ported by Steelcomp that have a smaller port, yet flow more across the board than my AFRs, and I say, "how the fuck did he do that." But can he reproduce the heads as quickly as a CNC. Not even close. And he used my heads to develop a CNC program. So they were on his bench for a looooong time. I was the perfect candidate because I didn't need the heads.
And I have heads that are CNC's that flow considerably less than my AFRs. Its all in the program.

In all this, nobody has even mention the tooling. It can be as important as the machine, and the operator. Hone a cylinder with the wrong hone for rings, and the bore is useless, I don't care what program was used to run the hone speed and travel.
If given the choice, I will take the CNC in the RIGHT HANDS!!

[gn7]

The best machinist now days started on conventional machines. Then learned to program by hand (actually need to know trig for this) and run tape. Then learned CAD/CAM. Then learned 5-axis. All the while collecting data in they're brains about materials, tooling, processing, etc. These guys are getting close to retirement now. Welcome the new age machinist right out of trade school that can't even describe how it feels to run a hacksaw through a beer can but he can CAD draw the shit out of an impeller.

Like I said in a previous post, the best of the best CNC machines is useless in the wrong hands. Even though the program could be perfect, the wrong tool/bad tool, on the wrong angle can be just as harming as the wrong speed/feed. A Sunnen Cylinder King in the wrong hands can jack up a cylinder worse than a 1950s Kwikway with somebody that knows what he is doing.

[SnoC653]

Sorry Sno, I can't agree with this 100%.
But a good machinist know a whole hell of a lot more than just the machine.

It takes a lot more old equipment to do what one modern machine can do today, but the basic shaping of metal hasn't changed. You can still only remove material in so many ways. Yes there are new tools to use and a lot more precise tools to use. Yes there are new designs that the old machines don't have the dexterity to accomplish, but it wasn't needed back in the day or else some engineer would have figured out how to do it with what they had back then.

And don't think I'm against the new machines. I think the advances in machine work is fantastic. I think the loss of so many great machinists and their replacements with operators is a tragic shame. I love talking to old machinists and hearing the passion for what they do in their voices.

[ogshotgun]

Bob wasn't talking about machines, he was talking about the operator of the machine.

i understand that .. so you agree a WW1 lathe will produce the same part as a brand new CNC will? with the same person running it that is?

one machine is over 70 years old it will produce the exact same quality of part as a new machine, as long as the operator is up to par?
I don't think so.

[ogshotgun]

I think you're missing the point. Regardless of the equipment, the person making the shit needs to know his or her shit. That's all that that's been or being said here.

didn't miss anything i agree the operator of the machine is where it begins , but i also do know that a process used 50 years ago was fine 50 years ago but times have changed and motors have changed since 1944 and materials have changed and more exotics available today than in 1944, i do remember you saying to machine this material you need a constant surface to cutter speed at all times so it must be done on a cnc machine.
the tool used at the other shop is nothing more than a pencil sharpener basically, i can not see the same quality coming off the two different machines . in fact my old shaft from the old supplier has chatter marks on the taper running length wise from the pencil sharpener tooling thats being used