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UPDATE on Machine Completion (Ref: I Need A Gear Made...)

Opsoff1 no matter what some of these guys are saying, these prices are outrageous. This is just an asshole way of saying we don't want the job. That said there is a lot of work to making a gear so expect to pay. if you can make the blank EG will cut it for you at a fair price.

Do you have a milling machine? As folks are saying you can cut a gear if you do. Especially since you have a good sample. Sometimes gears are cut at non-standard PDs but the sample will confirm that, and I'll bet your gear is standard.
I get that and totally understand - quite a few folks suggested Boston Gear. I had made inquires to them and they were very nice - I got a personal email from them that explained the small gear / one off type work wasn't something they could do as it was time and cost prohibitive.
I do have a milling machine and I do have another gear - same exact function, just from an earlier gearbox - it has a different shaft hole diameter and a keyway. It is in great condition. I am torn between modifying that one (and basically making that gear box inop) and continuing a search for a replacement or find a gear maker that can cut one.
Lot of great advice and leads to solve this small problem.
 
I get that and totally understand - quite a few folks suggested Boston Gear. I had made inquires to them and they were very nice - I got a personal email from them that explained the small gear / one off type work wasn't something they could do as it was time and cost prohibitive.
I do have a milling machine and I do have another gear - same exact function, just from an earlier gearbox - it has a different shaft hole diameter and a keyway. It is in great condition. I am torn between modifying that one (and basically making that gear box inop) and continuing a search for a replacement or find a gear maker that can cut one.
Lot of great advice and leads to solve this small problem.
If you've got a milling machine you can do it yourself. Better if you've got an indexing head but you can contrive an arbor held in a vise with your gear on one end and the blank on the other as other folks have said. Order an involute form cutter from Ash Gear or maybe you can find one on Ebay. Cut to the same dimension over pins as your existing gear. You can even hand grind a fly cutter tool with your exsisting gear a template.

Google "base pitch" to find an easy way to confirm pressure angle.

If you don't want to cut the teeth you've got a guy here that has offered to do that. Doubt you'll find cheaper unless you make a buddy of a guy that cuts gears for a living. And sometimes those buddy favor jobs cost in the long run!

It would be a shame to partially disable one lathe to fix the other
 
Take a 1" piece of round stock, turn one end to fit your good gear, turn other end to fit the gear you need, if gears are not keyed thread those shaft ends so you can lock gears to shaft. Make a center block to hold the shaft, slit one side so you can put a couple bolts thru so it can clamp onto shaft. Make a single tooth pawl that fits the good gear, you now have a little mini indexer. Put a gear blank on other end and start cutting gears, make some extras to sell on ebay.
 
If you've got a milling machine you can do it yourself. Better if you've got an indexing head but you can contrive an arbor held in a vise with your gear on one end and the blank on the other as other folks have said. Order an involute form cutter from Ash Gear or maybe you can find one on Ebay. Cut to the same dimension over pins as your existing gear. You can even hand grind a fly cutter tool with your exsisting gear a template.

Google "base pitch" to find an easy way to confirm pressure angle.

If you don't want to cut the teeth you've got a guy here that has offered to do that. Doubt you'll find cheaper unless you make a buddy of a guy that cuts gears for a living. And sometimes those buddy favor jobs cost in the long run!

It would be a shame to partially disable one lathe to fix the other
I don't have another lathe - just a complete separate gearbox albeit an older version - but the older gearbox will "work" on the current lathe - and then I can source or make the needed gear and reinstall that gearbox when its up and running.
There has been a lot of great advice and input from people here - so very tempting to tool up and make my own gear(s) but it may be a wiser move to have one made.
 
Why you guys think a wire edm is easier than a gear shaper or hobber that would cut those teeth in ten minutes max, unattended, is beyond me.

How many gear shops are going to setup for just one gear? Yea sure it's faster while cutting, but there's all the work req'd to get to that point.

To the Wire guy it's just another part. Clamp it to the table find the center, (or starter holes) hit start and walk away. Maybe stop the machine 1/2 way thru to add something to stop the gear falling into the machine, hit start walk away again. Sure the wire's going to take longer to run, but less time involved to get to that point.

Sure If you were making 10 gears, then the wire would be ludicrous.
 
How many gear shops are going to setup for just one gear?

Do it all the time, that's their job :)

Not everybody of course, but plenty. This part is a picnic, normally you'll have several arbors hanging on the wall, worst case is the bore is weird, you make a little bushing. Or even put it on a loose one and tap it in with an indicator.

If it's weird to hold then more trouble but this one is nothing. You can set up a 7 complete in ... lessee, five minutes to do change gears, maybe ten minutes to clean up the old mess you didn't do after the last job, go find the cutter takes five, put it on takes two, grab a coffee, set the stroke, five or maybe ten if you screw up and get the ratchet stuck again, take a test cut ten minutes, measure, five, cut to depth another ten, measure another five, if you hustle can be done in an hour. It'll take longer in real life but that's true of wire, too.

In fact wire is harder because where are you going to get the toolpath and how much backlash do you want and how will you figure it ? With a shaper or hobber, if you can't do the math then cut to size using standard numbers then just run the cutter in a few thousandths.

It's really not difficult, for a simple part like this.

Maybe Les talked it up big, some people do that because "oh wow, so much !" is the typical customer reaction to a $150 quote. As we see right here :)

Obviously if one were making a hundred the price would be less. And a lot of people have more overhead and a higher shop rate. But it's not expensive to the point of giving up. Cutting teeth is not magic. Around here there's so many posts spending sixty or seventy hours trying to avoid paying a shop $200. If you are a retired guy in his garage and think that'd be fun, cool. Yes, teeth look neat. And that's fine, but the aversion for a for-profit shop to pay a professional to get the correct teeth, it's weird. If i need to go to LA I don't buy an ultralight kit, put it together with bubble gum and fly myself, I buy a ticket (and snivel about the price, usually :) )

You can't take Rush as a yardstick, they are in another world doing another thing. For the price they ask, I could do this ...



(sorry, i gotta figure out how to get these upright)
 
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If it's weird to hold then more trouble but this one is nothing. You can set up a 7 complete in ... lessee, five minutes to do change gears, maybe ten minutes to clean up the old mess you didn't do after the last job, go find the cutter takes five, put it on takes two, grab a coffee, set the stroke, five or maybe ten if you screw up and get the ratchet stuck again, take a test cut ten minutes, measure, five, cut to depth another ten, measure another five, if you hustle can be done in an hour. It'll take longer in real life but that's true of wire, too.

You for got the xx minutes to make the blanks.


Maybe Les talked it up big, some people do that because "oh wow, so much !" is the typical customer reaction to a $150 quote. As we see right here :)

I think $150 is a most reasonable price personally

Les did talk it up big, but then for me he delivered big too. He did some id/od splined plates which nobody would quote, and the fit was as perfect as it was possible to get.

Les's biggest fan was the ex chief engineer of Lotus (during the Colin Chapman era) Martin Ware, can't get a better recommendation then that.



I those videos where going to be of a more interesting subject
 
You for got the xx minutes to make the blanks.

So the wire machine will do that for you, just toss a chunk of steel its way ? :D

Les did talk it up big, but then for me he delivered big too .... Les's biggest fan was the ex chief engineer of Lotus

Les is good, didn't mean to sound negative about him, gear guys are sort of a weird little group and many will rag on each other, just for fun.

Not as bad as grinder hands tho, you know that guy up in michigan ? what a wacko ! :D

I those videos where going to be of a more interesting subject

Oh. Okay, let's see what we can do ...

 
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I don't have another lathe - just a complete separate gearbox albeit an older version - but the older gearbox will "work" on the current lathe - and then I can source or make the needed gear and reinstall that gearbox when its up and running.
There has been a lot of great advice and input from people here - so very tempting to tool up and make my own gear(s) but it may be a wiser move to have one made.
There is a company called ST Gear around St Louis who probably would make one for you. They do one off stuff all the time. They made me a bronze power feed drive gear for an import lathe, and it fit and functioned perfectly. I just sent them broken parts and measured some stuff. The guy used to be on here, but I haven't seen him post in awhile. (disclaimer.... I did not read through all 3 pages of stuff to see if he's already mentioned or chimed in) :D
 
A lot of gear shops do one-offs. You just have to find one that suits you. Most will cut teeth on a blank you provide. Make sure your blank has minimum runout OD to the bore and is parallel. Send your sample gear to match so much the better. It is in your favor that you are most likely not in a hurry at all. Try Lawler Gear Corporation.
 
You got an out-loud "Wow!" from me with that assertion. How did you happen to learn this?

I worked with Martin Ware at Frontier, who were making a Helicopter UAV, he was the Chief Engineer. I was there to design the internals of a 6L, 6cyl diesel.

I left after I got pissed at him for throwing one of the young engineers under the bus. he was one of the best engineers I've ever worked with.

He used to talk about Colin Chapman, with respect, and also with some sadness at some of the shady stuff he did, which he alluded to but never expanded on
 
So the wire machine will do that for you, just toss a chunk of steel its way ? :D



Les is good, didn't mean to sound negative about him, gear guys are sort of a weird little group and many will rag on each other, just for fun.

Not as bad as grinder hands tho, you know that guy up in michigan ? what a wacko ! :D

Find the right wire machine, it'll tickle your b**** while it cuts.

Les, started out as a hair dressor of all things. A little weird would be a true statement. Probably why he's a bit flamboyant


Not as bad as grinder hands tho, you know that guy up in michigan ? what a wacko ! :D

My first real job in a proper machine shop (Hook Lane Engineering,Titchfield,Hampshire) was re-grinding blades for a bakery. Not sure why they thought I could do the job, but I got to say I fucked them up so badly I think they got thrown away. Ever since then I've had an intense aversion to grinding. I can grind ok on the Harig I have, but don't enjoy the experience.

When I worked at Geo Kingsbury's in Gosport, the ID/OD and surface grinders were over in the corner away form the turner/fitters/millers, cos they were just a little 'different'. Not quite the cross eyed drooling products of incest:eek:, but close:)
 
QT EG: (Not as bad as grinder hands tho, you know that guy up in Michigan? what a wacko! :D)
What? I'm a wacko.. I could make that gear using a Tc or surface grinder, agree it would take longer and be more costly than EDM (Not sure about EDM), shaper, or hobber...I guess a couple of hours with having a blank with the bore done....But "Wacko" is a bit harsh..

I have run Barber Colmans for sharpening hobs but never owned one...and have sharpened hobs and made gears with a Cinci #2..for rep replacement, not for new-to-spec gears.
Fudge making a gear it is good to have a gear of the same design to measure the form, it is difficult to measure a gear without having the proper equipment.
 
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One other aspect to the high-quote issue is than with most companies, the default way to do a job (like a gear) is the "correct" way, where there is a print calling out the actual tolerances that have been determined by thorough measurement or engineering, and they make it exactly within tolerance using the best cutting tools and the best measuring methods so they don't get it wrong. It's potentially over machined because that's the safest way to keep it from coming back a second time with an angry customer. This might be just an open rough duty spur gear, but it's very well possible that some of the high quote is that they don't know if it's going on an egg beater or in a Ferrari's transmission. The transmission gear would work on the egg beater, but not visa versa, so which side are they going to error on?

When you have a case where a precision part can be totally fine being a little on the sloppy or crude side, the obvious reaction is it should be cheaper, but without firm dimensions and expectations given to the maker, I guarantee it would be sloppy and crude in all the wrong ways. The idea that "they should know" is utter nonsense. We have jobs in this category come across the desk all the time and there's never "one way" that is just default knowledge to "professionals," UNLESS you specify it in writing. It's one reason why so many companies turn down the onesy-twosy job-shop work.

Making a gear like this shouldn't be hard if you have the tools and time, but there is a BIG difference when you have your own hands on the process and the mating pieces all at arms reach, and if you have to make two cause the first one didn't fit, that's not costing you while the next bigger $$$ jobs are stacking up behind you.
 
I worked with Martin Ware at Frontier, who were making a Helicopter UAV, he was the Chief Engineer. I was there to design the internals of a 6L, 6cyl diesel.

I left after I got pissed at him for throwing one of the young engineers under the bus. he was one of the best engineers I've ever worked with.

He used to talk about Colin Chapman, with respect, and also with some sadness at some of the shady stuff he did, which he alluded to but never expanded on

Very cool! I've worked with some very good engineers, but never a "celebrity" like Ware. And when I was younger Chapman was one of my racing heroes, but I do admit to some reassessment when I realized how many of his drivers died or were injured...
 
Very cool! I've worked with some very good engineers, but never a "celebrity" like Ware. And when I was younger Chapman was one of my racing heroes, but I do admit to some reassessment when I realized how many of his drivers died or were injured...

I think it was Sterling Moss who said that at the start of the season he would look around the grid, knowing that by the end of the season some would be gone.

Somebody did a study of big wave surfers, as to why they did what they did. The conclusion was that there was a certain lack of imagination, in other words if they thought thru what they were about to do, and what could go wrong, they wouldn't do it. I think the same applies to racing drivers, motorcycle riders etc etc. Especially Motorcycle racers and F1 drivers in the 50's/60's.

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Same applies to starting a machine shop. If you really thought it thru, examined all that could go right and wrong, would you do it? I'm 50/50 if it was the right move
 








 
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