Not sure. I don't have any way to test it. I got the bearing pocket in, broke the edges and decided to take a break. There's a fair amount of metal to remove from the front, and the threaded holes.
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Group Project: Rotary Broach-- Building complete, all shipped out!
- Thread starter ErichKeane
- Start date
Not sure. I don't have any way to test it. I got the bearing pocket in, broke the edges and decided to take a break. There's a fair amount of metal to remove from the front, and the threaded holes.
Mounting to a mandrel seemed to help keep space around the flange. After a few passes, I found some good settings for roughing this material and was peeling about 0.90/pass off.
Hmmm.. Finish looks worse on the pics than in person. Can barely feel a few ridges with a fingernail.
After drilling and tapping the holes, I use the lathe to run some emry over the back flange. It cleaned up nicely without much work.
I spent some time with calipers and mics and everything looks great. Guess I need to make a few copies now.
I spent some time with calipers and mics and everything looks great. Guess I need to make a few copies now.
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That's awesome! I was wondering, do we all send our part to Erich...for assembly, make sure all is well? Or just hail Mary it?
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That is what the other projects do, saves everyone a bit on shipping that way. And the hope is I could choose the ones that suffer the least from tolerance stacking.
Doesn't have to be me of course.
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@ErichKeane You're probably past this point, but take a look at this this video.. by using compound, did they pull off the front (cupped area?)
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Haven't actually started yet! You guys are going too fast I'm still working on my dividing head parts! I'll watch that though!
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Huh really interesting! I had actually been considering that a bunch lately, wondering if I could use some of my brazed carbide tooling plus the compound to cut the cupped area.
I hadn't thought about actually cutting the profile that way though, that is a really good idea! I can probably save my surface grinder a lot of grinding that way
Seems like a reasonable way to do it. I'm happy to send to whoever. Whatever works. I think you might be a good choice since you did the drawings and likely understand the way tolerances will stack more than we will, but I'll give it a go if you prefer. I've still got a few more to make before it's an issue for me.
I'm interested in seeing more parts getting made as everyone gets time to do it, please post a pic or two. I think I need to do one before I clean up after doing the big material removal step. It makes a hell of a mess.
Looks like we're making 4 total units? That's what I'll plan for unless someone says otherwise.
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Yep, 4 total! I don't mind any setup, just know I'm probably a bit behind all of you all I haven't started up yet, I still have a bunch of dividing head parts to make. That project got bit big/complicated (7 or 8 copies! AND I have to learn to hob gears), so I have a ton of turning to do. Plus it just hit 110 today here in Oregon, so I'm off of shop time for a few days!
I haven't started up yet, I still have a bunch of dividing head parts to make. That project got bit big/complicated (7 or 8 copies! AND I have to learn to hob gears), so I have a ton of turning to do. Plus it just hit 110 today here in Oregon, so I'm off of shop time for a few days!