Mechanical Engineers Needed - What's Needed to Overcome Prop Pressure

[VDRIVERACING]

A kill switch?

[MAXIMUS]

There seems to be acknowledgement that the propshaft places tremendous forward pressure on the Vdrive plate.
1. What is the formual to calculate that force?
2. How much of this force can a 1/2" plate resist? And, therefore, how much of the uncontrolled force needs to be controlled trough attachments from the plate to the stringer.
For example: a 1500 pound boat, 750lbs torque, 22% overdrive, and 20% slippage. How much force is on the vdrive plate, and at what angles?
Have you...by any chance been harvesting oregano lately???
:shift:

[lilrick]

There seems to be acknowledgement that the propshaft places tremendous forward pressure on the Vdrive plate.
1. What is the formual to calculate that force?
2. How much of this force can a 1/2" plate resist? And, therefore, how much of the uncontrolled force needs to be controlled trough attachments from the plate to the stringer.
For example: a 1500 pound boat, 750lbs torque, 22% overdrive, and 20% slippage. How much force is on the vdrive plate, and at what angles?
Bill, you gotta find something to do....:D By the way you left your sunglasses at Heaths yesterday

[gn7]

hang tight R.D. will be here shortly

[RiverDave]

hang tight R.D. will be here shortly
I figured I'd just go the PM route if he actually needed help. ;)
Incidentally it should be noted.. I am not an engineer just been around an engineering firm my whole life.
If an when I can help someone on the forums though with something that might be useful, I will always do my best. After all that's the point of this place isn't it?
RD

[VDRIVERACING]

Rick - Thanks for the info. I wondered why I was swerving around the freeway so mucsh...

[superdave013]

Incidentally it should be noted.. I am not an engineer just been around an engineering firm my whole life.
You know, I've always wondered why you never went to school. You have the smarts for it. You should stop f'in around and go full time and knock it out. What's 4 years now compared to the rest of your life? It will be the best thing you could ever do and the one and only thing that can never be taken away from you.
God I'm sounding just like my dad. :eek:

[Unchained]

I'm not an engineer either although I've fabricated and installed hundreds of tons of steel. I've got welding experience in almost all types including submerged arc (no welding helmet req'd.). Had some certifications too.
My dad wrenched hard on me back in the 70's to go to college and get a degree.
I refused because I already knew it all. :rolleyes:
I put my two daughters through college but my son refused to go because he already knows it all too. I can't imagine where he got that from.
My son in law IS a structural engineer and he would be able to figure out any of the stuff we discuss here. He'd figure it out and bury us all in facts and numbers :)

[Racey]

I'd Love to hear what an engineer had to say on the subject in reguard to actuall force numbers, it'd be pretty interesting. If you eliminate things like water friction/drag from the equation, and simply figure out how much force is required to accellerate an object of X weight, to Y speed, in Z Time it couldnt be that complicated.

[superdave013]

I'd Love to hear what an engineer had to say on the subject in reguard to actuall force numbers, it'd be pretty interesting. If you eliminate things like water friction/drag from the equation, and simply figure out how much force is required to accellerate an object of X weight, to Y speed, in Z Time it couldnt be that complicated.
Newton figured that out a long time ago.
Newton’s Laws of Motion
1. An object at rest will stay at rest, and an object in motion will stay in motion at constant velocity, unless acted upon by an unbalanced force.
2. Force equals mass times acceleration. F=MA <- this will answer Racy's question.
3. For every action there is an equal and opposite reaction

[superdave013]

I'm sure Newton was a cool dude. But did you know that one newton is equal to the force required to accelerate one kilogram of mass at one meter/second/second? Well now you do. :)

[superdave013]

oh, and Newton was living in a vaccum. There are other forces like gravity and friction that come into play. But in outter space he's right on the money. That's how the space shuttle gets the great fuel milage.

[gn7]

the amazing fact is that newton figured all that out without ever talking to RD

[RiverDave]

the amazing fact is that newton figured all that out without ever talking to RD
What are you talking about?? I was Newton in my last life!
RD :jawdrop: :jawdrop:

[superdave013]

What are you talking about?? I was Newton in my last life!
RD :jawdrop: :jawdrop:
yeah to bad you were a Fig Newton! :D
http://images.google.com/images?q=tbn:iuQJzUxp8_I_sM:waynesword.palomar.edu/images/fig1.gif

[gn7]

R.D. reach down and get a firm grip on your ears and JERK YOUR HEAD OUT OF YOUR ASS, now get get back to work retipping shoe laces

[RiverDave]

R.D. reach down and get a firm grip on your ears and JERK YOUR HEAD OUT OF YOUR ASS, now get get back to work retipping shoe laces
Flugel binders? I LOVE flugel binders!! :)
I thought you knew I'm off that line though.. I'm over at the little umbrella factory now. You know the ones for tropical drinks?
RD

[gn7]

did you get a raise?$$$$$$$$$$$$$

[RiverDave]

did you get a raise?$$$$$$$$$$$$$
Damn Straight I did!! There's moving parts in the umbrella! This is some technical shiznit up in here! I'm almost up to minimum wage now! ;)
RD

[superdave013]

Hey Dave, hate to get off topic but I'll have my cnc machine fixed by Monday. Just next day aired the part off to get fixed. That's right, fixed not replaced. No replacement parts for this old girl. 97 bucks in next day shipping each way sucks though.
Anyway, kinda stoked to get it up and running again. A bunch of work just rolled in for it so that got me off my ass to repair it.

[VDRIVERACING]

I'm not an engineer either although I've fabricated and installed hundreds of tons of steel. I've got welding experience in almost all types including submerged arc (no welding helmet req'd.). Had some certifications too.
My dad wrenched hard on me back in the 70's to go to college and get a degree.
I refused because I already knew it all. :rolleyes:
I put my two daughters through college but my son refused to go because he already knows it all too. I can't imagine where he got that from.
My son in law IS a structural engineer and he would be able to figure out any of the stuff we discuss here. He'd figure it out and bury us all in facts and numbers :)
Well then, get on the phone and let's get some answers! All kidding aside...uh, better forget that...
I think if we really understood the forces at play on our driveline it would give us pause to reflect. A buddy who is invloved with the big offshore race boats told me of a team that mounted a high speed camera trained on their engine compartment. The film revealed how the hull twisted violently in race conditions, to an extent they had never imagined.

[wsuwrhr]

After being broke for three months, what is the rush?
I wonder about you sometimes.
Hey Dave, hate to get off topic but I'll have my cnc machine fixed by Monday. Just next day aired the part off to get fixed. That's right, fixed not replaced. No replacement parts for this old girl. 97 bucks in next day shipping each way sucks though.
Anyway, kinda stoked to get it up and running again. A bunch of work just rolled in for it so that got me off my ass to repair it.

[wsuwrhr]

...which bears resemblense to the comment I made in the closing of the V-drive mounting plate thread.
All the bracing in the world is no good when it is bolted to a peice of wood and fiberglass.
A buddy who is invloved with the big offshore race boats told me of a team that mounted a high speed camera trained on their engine compartment. The film revealed how the hull twisted violently in race conditions, to an extent they had never imagined.

[gn7]

...which bears resemblense to the comment I made in the closing of the V-drive mounting plate thread.
All the bracing in the world is no good when it is bolted to a peice of wood and fiberglass.
This is the part I don't get about this whole plate thing. The strut is flopping back and forth (if they didn't, no one would ever crack one), the shaft is whipping like a snake in hot oil, the boat itself is twisting a flexing like mad and thru all this they are trying to keep the V-drive/shaft alignment lazer straight. They are kidding right?

[superdave013]

After being broke for three months, what is the rush?
I wonder about you sometimes.
Well as you know I was just about ready to scrap it out. I didn't what to put good money into such an old machine. And as soon as I got the # for the guy that removed some stuff from the shop next door my phone rang. It's a job I've done before on that machine and would more then pay for the repair.
So I'm now fixing it. I still might get rid of it. But it's going to be worth something running and that seems better then just giving it away for scrap.
I'm hoping you will upgrade soon before mine breaks again. That way I can sell it running and pick your old one.
I'll tell you what. You man up and buy that new VF3 and at the same time I'm man up and buy your old one and pick up that gang tool lathe I'm wanting. What do you think?

[wsuwrhr]

I'm working on it buddy, you just keep a spot warm on the floor for it.
I'm sure we will have a deal, problem is fixing your mill would cost $500 for parts. Easy deal, done.
"Man-ing up" to buy a VF3 $80,000, bigger house with more land $500,000,
new shop construction 30,000.
Makes your $500 part seem free to me.
Brian
Well as you know I was just about ready to scrap it out. I didn't what to put good money into such an old machine. And as soon as I got the # for the guy that removed some stuff from the shop next door my phone rang. It's a job I've done before on that machine and would more then pay for the repair.
So I'm now fixing it. I still might get rid of it. But it's going to be worth something running and that seems better then just giving it away for scrap.
I'm hoping you will upgrade soon before mine breaks again. That way I can sell it running and pick your old one.
I'll tell you what. You man up and buy that new VF3 and at the same time I'm man up and buy your old one and pick up that gang tool lathe I'm wanting. What do you think?

[superdave013]

sucks to be you then. :) lol
And I know all about the big money. That's why I'm still a little gun shy to pull the trigger on the lathe. I gotta sack up and do it pretty soon though.

[wsuwrhr]

Yep
sucks to be you then. :) lol

[Unchained]

CNC mills and lathes lose about 90% of their value in 5 years and the machine can still be real nice.
We've moved a few through our shop. One was especially nice with a tool changer and a nice enclosure and it went for around 4k. Another machine 20 yrs old went for less than 2k and the ball screws were still real tight.
The guy who bought my old building has excess equipment auctions every 90 days and they always have some nice CNC machines going through there. There was a pretty large Cinncinnati Milocron that went for about 10 k.
For the kind of stuff we use here accuracy to the .0001 is not required like it is for production work.
There are lots of companys dumping machinery cheap here in Mi. where the economy is dead. We are the only state where property values have decreased in the last year.

[wsuwrhr]

90% in 5 years?
So you are saying a 100,000 machine is worth 10,000 in 5 years?
You are kidding right?
CNC mills and lathes lose about 90% of their value in 5 years and the machine can still be real nice.
We've moved a few through our shop. One was especially nice with a tool changer and a nice enclosure and it went for around 4k. Another machine 20 yrs old went for less than 2k and the ball screws were still real tight.
The guy who bought my old building has excess equipment auctions every 90 days and they always have some nice CNC machines going through there. There was a pretty large Cinncinnati Milocron that went for about 10 k.
For the kind of stuff we use here accuracy to the .0001 is not required like it is for production work.
There are lots of companys dumping machinery cheap here in Mi. where the economy is dead. We are the only state where property values have decreased in the last year.

[Unchained]

OK maybe I should have said "some CNC machines" lose 90% of their value in 5 yrs.
I've seen it many times though. Companies that have production jobs need the latest high speeds and feeds and can justify the high cost of a new machine.
When those requirements are not important, like for machining aluminum parts for boats, a used machine will work just fine. The one I used on my intercooler box that was 20 years old was still real tight (ball screws) but the control was an off brand and the it didn't have a tool changer but it worked fine for what I needed and it was miles above any hand jammer machine. It sold for less than 2k.
A good friend of mine is a CNC machine repair man and my ex bro-in-law is a CNC electrical technician. Some of the deals they come across get a CNC machine for less than a hand jammer Bridgeport would bring. Once you've used a ball screw machine, you never want to go back to an old lead screw machine.
There are some who would always pay more for a hand operated lead screw machine than they would for a CNC ball screw machine because they don't want to learn any CNC programming.

[superdave013]

Unchained, I own that 20 year old machine with out a tool changer. And you are right, ok to tinker with but you won't earn a living with it. See, this is no hobby for me.
I go lucky that only a servo went bad. If it was a spindle or AC drive I'd had to push it in the scrap heap.
Also I need something that will run unattened. I can buy a pretty nice machine for less then hiring someone to change tools in what I have now.
I'm looking at used stuff too. I'm sure I'll go that route when I get a bigger lathe (like a 6~8" chuck). What I'm after right now is a small lathe for bar work. The one I'm looking at will drop the part off in 22 seconds and costs about as much as a nice 3/4 ton truck. Maybe a little more with the bar feeder.

[VDRIVERACING]

This is the part I don't get about this whole plate thing. The strut is flopping back and forth (if they didn't, no one would ever crack one), the shaft is whipping like a snake in hot oil, the boat itself is twisting a flexing like mad and thru all this they are trying to keep the V-drive/shaft alignment lazer straight. They are kidding right?
I agree with you in the sense that GN boats are a difficult environment in which to maintain certain alignment characteristics. My goal is to seek out and mitigate the odds of a mechanical failure, or some characteristic(s) negatively affecting handling/performance.
In some cases, a strategically placed wrap of race tape can be of enormous value(across driveline cover bolts, for example). Preventing vdrive failure and/or prop creep may prove more of an engineering challenge, but are goals worthy of consideration and persistance.

[Unchained]

All this talk about machine tools caused me to dig up a machine shop trivia question.
What machine tool can remove the most metal per hour.........in relation to the weight of the machine ?