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Here in kilogram meter zone, there's a simple answer; a 1 meter breaker bar with a pull scale on it.
I suppose you could rig up something to test foot pounds easy enough if it's worth the trouble. You just need to be confident of the weight used.
In reality, I think 10% error will do you.
 

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Made my first ever gear from scratch today!! Well, between yesterday and today...

A bit of the backstory. I bought a reciprocating saw on Lidl, intended for pruning trees. It's wonderfully. An awesome and handy little tool.

Well, turns out I caught an hidden nail inside a limb and broke a tooth of the gear. I still used for a bit till it got frustrating to use as it would get stuck on the broken tooth and just make an awful grinding noise.

Anyway, I took it apart, built the broken tooth up with weld, shaped the tooth with a small dremel cutting disc and files. Off she went. Only to start grinding shortly after.

I took it apart again, ran it a little bit and noticed some odd runout on the gear. Turns out they made the gear using this sintering process. Basically they make a mold for whatever part they want, fill it with a metal powder, press it together along with heat and they have part made. No machining required. A common process. Most final drives on the front axle of compact tractors are made using this process.

Somehow they messed it up, and the teeth of the gear had a lot of runout in relation to the bore where it rides. To the point of getting a full tooth engagement on one side and almost nothing 180 degree apart. So the grinding was just the pinion riding on top of the teeth where it barely engaged.

I then proceed to make a new entire gear. Mostly for the challenge of it. The saw was like 30€ ($35). Could just get a new one but where is the fun in that, right?

It had some challenging features. Like a diameter offset 5 mm on one side and a small boss on the other side, also off set about 10mm for a small hardened pin.

I prepped a blank with the major dimensions on it. Grabbed another piece of material, centered on the milling machine and drilled two holes on the face. One with a 5 mm offset and other with 10mm. Chucked this piece on the lathe, bolted my gear blank and machined on side, then flipped it over and did the other side.

Then I moved to the milling machine again, set up my homemade diving head. I had to grind a tool bit with the shape of the tooth, kinda tricky with such small tooth. After I had all set up and ready to go, I could finally start cutting the teeth. Everything went surprisingly well and I was very very happy to see that when I did a full revolution with the dividing head and come back to the first tooth I cut, the tool bit wouldn't cut anything, which means the indexing of the diving head is spot on!

After some filling to take the sharp burrs off, I tested the gear and it's just working beautifully. Just slightly noisier because I couldn't get the shape of the tooth 100% right, but I'm like 85% there.

The pinion does have some damage but they made it twice the width so I can just flip it over and have fresh and sharp teeth again.

Old gear on the left.

IMG_20200911_152836.jpg IMG_20200911_152811.jpg

IMG_20200911_152847.jpg IMG_20200911_152922.jpg
 

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Now THAT is really really cool!!!
Glad that your creation, the indexer worked flawlessly, also very impressive. I have a couple of cheap Harbor Freight hand held grinders that need gears but they were sooo cheap, like $14 bucks they are not worth the trouble, but would have been fun trying to cut the gears. That was before I had a lathe. Now the project is using the generic high torque 20 v motor to turn it / them into cordless grinders. One day when I have the time. It needs a bushing made. . . . . .
The powder metal process was what GM turned to for connecting rods in the LT1 motors, replacing the old pink rods which were very strong.
Good job and great pictures as usual. (y)

Don

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Awesome job on the gear. When I used to work maintenance at the paper bag plant, we had one machinist that was amazing at gear making. Always perfection. I love to watch him work.
 

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Gear making; that'a a machining milestone, congratulations on your success, first try too.
A real validation of your dividing head too. That thing is like a spaceship to me.
 

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I've been looking at a satellite heat map of Oregon and California; there are fires everywhere, it looks really terrifying.
I was looking for a steak like pattern on roads near Don's place but I can't see anything.
I guess the big V8 hasn't been fired up yet...

 

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Thanks everyone!

It's indeed quite a milestone. There a lot more to machining a simple gear but to get the job done, this method worked great.

I'm with Mark. That's scary seeing that fire map. I hope everyone is safe out there.
 

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Made my first ever gear from scratch today!! Well, between yesterday and today...
Wow, great work, that's amazing!

I'm still trying to figure out the best way to post pictures. For me, at least, the ones in your post are just thumbnails, I can't click on them for larger versions.

I usually click "Insert image", then delete the full-size version that it inserts, and do Insert Thumbnail, which gives a small version that you can click on to enlarge.

But some people include their pictures as attachments, apparently, and they look different in the posts. More like what I'm used to with older forum software. I haven't figured out how to include them that way, I tried the Attachment button, but still got the same result, as I recall.
 

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Thanks Red! And also thanks for pointing out that you couldn't see the full size image. I didn't realize that it wasn't working correctly.

I believe I fixed and should be working now. Can you test that out? Thanks.
 

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The last picture, with the gears mounted on the saw, is currently clickable, and will show a large version. But the first three are not clickable, and are just the smaller thumbnails.

I'm not certain whether the last picture was clickable before. I thought none of them could be clicked on, but it's possible I didn't check the last one closely enough.
 

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Ok, I fixed the other three. I only had fixed the last one before to see if that worked.

Turns out that after uploading the attachments, I to scroll down a little bit to the list of attachments and click on Add thumbnail. Then it works well.
 

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There we go, now they're all clickable, and you can see more detail. Awesome job! That is really impressive.
 

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I just right click and then view image, then click my back mouse button.

Don

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I just right click and then view image, then click my back mouse button.
Interesting, thanks! When they weren't clickable, I figured that was the "entire" image quality, that it was just thumbnail-size. But I tried it with one of @ptsg 's previous posts:
My latest Project - Part Two

And you're right, it brought up a higher-resolution version. Not terribly intuitive, but good to know that it's something to try.

Edit #1- wait, now that one is clickable for me. Perhaps just losing my mind. But in this post, the second picture, "One of her child, another girl:", is not clickable, but does show a higher-resolution version when I right-click, and do View Image.
My latest Project - Part Two

Edit #2: Augh, OK, now the second picture, "One of her child, another girl:", is clickable for me, for opening a larger version. And I promise I had just checked it. Maybe something weird with Firefox? Or my computer? I don't know. I tried that post in Chrome, as well, and all the pictures now show as clickable. Not sure what's really changing, if anything.
 

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Well, computers are magic, sometimes good and other times, not so much. Just FM. :ROFLMAO: At least the option is there. Other times when a picture is intentionally unavailable, you have to go to tools, page info then wait for the media icon to show and click it then scroll thru all the images, up down arrows work faster than clicking. Find the image and choose save.

Don

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