Wrong way fly cutter

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ChazzC

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Always wondered why there are no left handed angle grinders .
Would be so handy in certain situations .

Same for calipers . Altough they seem te be avilaible now .

Pat
I got a left-hand digital caliper a while ago to use on my mini-lathe without having to move the bench so I could walk around it.

About half of my hardware seems to be left-handed: the pointy parts are always on the wrong end, and it's getting harder to take the bad ones back for exchange.
 

Bentwings

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Ken,

That is a great example of Poka-Yoke. Designing something so that you can't assemble it wrong is something most designers should but often don't consider.

Another option would be to make the castellations or other features such that it obviously doesn't go together right when you put it together wrong.

I used to work in sheetmetal and there was always a chance you (or the shop floor guys) could bend the part inside out. And sometimes you could design that out of the parts / assembly. And sometimes you can't. Sometimes you can put centerpunches or similar features in (using the machine) to be able to help know which side is which. But sometimes the turret was full and that wasn't a choice. But thinking through the process was important.

James
As engineer we sat through many meetings doing poky yoke. No matter how idiot proof you make it there is always some that just don’t get it. I did a complete fully enclosed punch press guarding . The operator took the guard off because it was in the way and got is hand nearly smacked off. There was a stop block that prevented it from closing pas the wiring depth. Lucky for him he only got broken wrist and ripped finger nail off. Had to add non op switches to each press that it wouldn’t run even if guarding was removed plus safety fence so if guard was removed the thing could not be forced to move by hand. He was lucky, could have been added to the unemployed for blatant rules violation.
byron
 

JLaning427

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Bentwings, you are absolutely correct, there is zero way to completely idiot proof something.... (had to go fix bentwings, my phone autoincorrected it to "beatings").

I had a similar experience with punch press guards in a particular department. We would design guards, fab them up, install them, and a week later they'd be in the corner. Obviously this wasn't acceptable, to management or OSHA. I took this as a professional challenge.

The solution was to listen to production's concerns (about ease of use and "this machine needs to run 18 hrs a day") and design something that was difficult and expensive to build but easy to use and hard to remove or defeat. Ended up with a hinged guard, with a gas shock to hold it open ( the gas shock also went over center so it held it closed too!) with an integrated safety switch that wasn't easily bypassed. Had lexan windows in it so you could see the material running through. Safety switch pulled motor power to the flywheel and disabled the mechanism that pulled the dog on the clutch. The safety switch helped keep it closed. Swung up out of the way so you could get to the dieset for any purpose (referring, clearing a jam, changing dies, etc).

Was so easy to use that they actually did. In fact, we rebuilt all that size machines in the department that way (probably 10 machines). They had one oddball that was twice as big, and production begged me to design a similar guard for it. Took a bunch more thinking to build one for that piece and it wasn't nearly as slick (ran on drawer slides instead of hinges). But I left there 8 years ago, and all of those guards are still in use. In fact they've even built more as they had additional machines built, to basically the same design.

I'm not 100% sure if it would meet all of OSHA's requirements for guarding punch presses. But a guard that gets used every single day is way better than an unguarded machine.

That story is a long way from left handed anything. But it was a small triumph of ingenuity and hard work overcoming stupidity, and thought it worth sharing.

James
 
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Bentwings

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I used to see drawings made in 3rd hand , with some details drawn 1st hand "for clarity"! Almost always were made cack-handed!
K2
Yeah I like that forum too. Some great guys there . Also just got on Office of stem. Lots of steamers there. I do a couple of Rc model plane forums too. My youngest son and kids are following dads trail with giant scale warbirds. Another hobby I miss.
byron
 

SmithDoor

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I am on of one RC sites too.
I even have drawings I planing to build a small rc engine.
I am staying with small size rc.

Dave

Yeah I like that forum too. Some great guys there . Also just got on Office of stem. Lots of steamers there. I do a couple of Rc model plane forums too. My youngest son and kids are following dads trail with giant scale warbirds. Another hobby I miss.
byron
 

Bentwings

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Yeah I like that forum too. Some great guys there . Also just got on Office of stem. Lots of steamers there. I do a couple of Rc model plane forums too. My youngest son and kids are following dads trail with giant scale warbirds. Another hobby I miss.
byron
I just though of something else for lefties. Remember the old drafting boards? I remember someone in one class ran his tee square on the “ wrong” side I think he may have tried the arm too but I don’t remember it working I think I didn’t fit that was the one thing I disliked in English. School was drafting I scored top of class but hated every minute as I knew cad was coming and I was already in CBC in tool and die class. It was realy rewarding when I got to operate in full paperless shop . The internet was just starting but already invaluable even in early days. I took care of the eng cad and the giant even in the day a ax central computer it had its own environmental room no smoking no drinks no water even the backup power station had nearly hundred big lead acid batteries and it’s own climat room. It’s funny now but the central computer was big business back then. I’m going to get back to steaming . I just found a place that has all kinds of model steam stuff. I’ll check in later and share the link .

byron
 
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As engineer we sat through many meetings doing poky yoke. No matter how idiot proof you make it there is always some that just don’t get it. I did a complete fully enclosed punch press guarding . The operator took the guard off because it was in the way and got is hand nearly smacked off. There was a stop block that prevented it from closing pas the wiring depth. Lucky for him he only got broken wrist and ripped finger nail off. Had to add non op switches to each press that it wouldn’t run even if guarding was removed plus safety fence so if guard was removed the thing could not be forced to move by hand. He was lucky, could have been added to the unemployed for blatant rules violation.
byron
To quote the old engineering adage " It's impossible to make a foolproof design because fools are too d----d ingenious"
 

justisla

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Older son flys giant scale Rc warbirds. Radios have two modes but neither favor handiness.
Futaba 2 stick model transmitters for flight have 4 modes, not 2, so can be easily set up for left handed persons. We have a couple in our club
I believe Simrad & all the other mainstream makes have the same function. So your son clearly does not trust you with his decent models😁
 

justisla

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That is a great example of Poka-Yoke. Designing something so that you can't assemble it wrong is something most designers should but often don't consider.
If you saw the engine in my boat you would think that some idiot solved that problem because he designed it so you could not get to it to get it apart in the first place 🙄
 

justisla

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If look in download section I have uploaded drawings and photo of my fly cutter. The angle of fly is low for a smother finish and can be made on most small mills.
Hi. I am interested in this comment about "angle of the fly". I assume you mean that the cutter ( piece of tool steel) is more at right angles to the axis than might be expected ( whatever one might expect of course!!) So 2 questions:-
How does that make it easier to make on a small milling machine- I need a fly cutter
& secondly, surely the angle of the steel blank itself is irrelevant because it is the grinding of the actual cutting part that matters. One just grinds the part that meets the work piece to a shallow angle & the tip does not tell the workpiece- "hey I am on the end of a bit of steel held at 45 degrees, or whatever" It could be a t the vertical for that matter- Or am i talking nonsense? - Please be gentle, as I really do not know & want to.
Sam L
 

Bentwings

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To quote the old engineering adage " It's impossible to make a foolproof design because fools are too d----d ingenious"
You certainly got that right. I think today’s auto engineers should be safety engineers. Ever try to do a simple task on a modern car. Most you can’t even see the engine. You need special tools for about every task . The 10 page owner manual has evolved to over 100 pages it takes a couple days to wade through it then you have to make calls to activate and install special apps.
byron
 

SmithDoor

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I made fly cutter with red bench mill and a 9" SB.
I could have purchased one but did not like the angle and most would stick out from the spindle.

Dave

Hi. I am interested in this comment about "angle of the fly". I assume you mean that the cutter ( piece of tool steel) is more at right angles to the axis than might be expected ( whatever one might expect of course!!) So 2 questions:-
How does that make it easier to make on a small milling machine- I need a fly cutter
& secondly, surely the angle of the steel blank itself is irrelevant because it is the grinding of the actual cutting part that matters. One just grinds the part that meets the work piece to a shallow angle & the tip does not tell the workpiece- "hey I am on the end of a bit of steel held at 45 degrees, or whatever" It could be a t the vertical for that matter- Or am i talking nonsense? - Please be gentle, as I really do not know & want to.
Sam L
 

Bentwings

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I made fly cutter with red bench mill and a 9" SB.
I could have purchased one but did not like the angle and most would stick out from the spindle.

Dave
I never really liked using a fly cutter excep on easy to cut materials aluminum brass. Most of what was done while I was in the tool shop was tough stuff tool steels 4230to 4250 some times hotvrolled steel and stainless steels between making horrible noise they threw hot chips everywhere and made big messes you had to crunch walk threw. I think the bids man got tired of it to after some milling machines started needing repairs eventually the tool supplier cam in and we got nice insert tools. Even some of those got high speed steel inserts that we could fine tune aluminums started liking like polished mirrors snd the steels started getting finished faster and better . There was a lot less grinding. Except for tool sharpening . We even had some of the first ceramic bits we got much better coolant systems so there was less coolant flying around. I think we got more and better brooms too LOL even today in our little model shop we have gone away from the fly cutter to insert cutters . I have a lathe tool I got forvthevboysvthatbhas high speed steel that gets fine tuned hone ing and finishes are getting pretty good now. The target insert tool has high speed thread inserts that really work nice when tuned a little my old hones I got from the Norton rep gosh 50 years ago still work great we’ see how it shakes out on the boiler parts I wish I could be turning the cranks. About all I’ve been able to operat lately is the hand snow shovel and I’m supposed to go easy with it. I have to monitor heart rate and blood oxygen . So far perfect I got a new lighted magnifying glass on an arm that is helping some at least I can see two clear images it’s just selecting which one to use. LOL KITTY JUST CURLED P ON THE BOTTOM OFVTHE ELECTRIC BLANKET I THINK I HEARD AMAZON. Gotta go check .
Byron
 

LorenOtto

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Try this for left and right.
Try find a left handed by looking at how they use a computer mouse.

Now try to find a right handed person using the with left hand.

Both my wife and my self are right handed but we use a the mouse on the left hand keep the right had for the number keys.

The first time we both saw a mouse being the person was using left handed.

Dave
Like you I am right handed with most everything, however I taught myself to use the mouse left handed because I found I needed my right hand to do most of the typing on the keyboard.
 

Bentwings

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Like you I am right handed with most everything, however I taught myself to use the mouse left handed because I found I needed my right hand to do most of the typing on the keyboard.
I agree switching hands is tough. Bowling was the only sport I had success. It purely mechanical motion. Power comes through exercise base ball is different batting both sides is hard to learn but if started early and proper exercises are done is possible Nicky mantle good example throwing is something different . Doing this two keyboards super imposed is another thing that’s very difficult. Can’t even see your own mistakes as you have seen me do. I’m too old to get frustrated.
byron
 

Bentwings

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I agree switching hands is tough. Bowling was the only sport I had success. It purely mechanical motion. Power comes through exercise base ball is different batting both sides is hard to learn but if started early and proper exercises are done is possible Nicky mantle good example throwing is something different . Doing this two keyboards super imposed is another thing that’s very difficult. Can’t even see your own mistakes as you have seen me do. I’m too old to get frustrated.
byron
Haha that’s funny boat designers come from another planet. Most likely one that doesn’t have water. Modern cars are really y bad but even ancient boats are worse. I think I’m not sure whether poor car engineers went to boats or the other way around. There is nothing light weight in a boat if it’s electrical only a bird could find it’s way around the wire mess. Interior designers and builder are carpenters that couldn’t make in the world of wood working they like to box every thing in with lots of fasteners and glue with no thought that some one might have to service the stuff some day. I think they just hope it’s not then that has to work on stuff. Why would you completely frame the sink, stove and refrigerator in so all that has to be removed to service any one of them . I won’t even get to the head. I’m just glad to be out of the boat. They are dust a big hole in the water that you deposit your pay check into .
byron
 

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