Hello. We are looking for six 1/2" hex miter gears, Vex p/n 217-5907 or three Armabot right angle drives with these gears. Please message me if you have any you can part with. We can pay money or trade CIMs.
We don’t have any, but it looks like this place has them in stock.
We also need those but cannot find them. Do you guys have a cnc? We will most likely buy a miter gear on McMaster and machine a hex into it with our cnc.
It looks like they are only authorized to resell Vex stuff in Canada. If you switch to the Canadian site, it shows a price.
looks like they are only available in Canada.
You can’t machine the hard corners of a hex with a CNC mill (using conventional tooling, anyway). The tool you will need is a hex broach, which is available off of McMaster / AndyMark / etc for just under $200. It’s a handy tool for many applications, so it may be worth the long term investment if used carefully.
1 Like
We have two armabot right angle drives we can ship you. I could probably get them out today if you want them. Let us know. Zach
I can get similar un-hardened 1/2" plain bore gears and broach them, but I was hoping for these VexPro gears ready to go for convenience. @Fowler509 I sent you a message.
I have the same need and think I have a somewhat different solution. I’d be interested in hearing opinions on, well, if I’m nuts.
(1) 1/4" shaft stock ( https://www.mcmaster.com/1257k113 )
(2) bevel gears that press-fit into 1/4" stock ( https://www.mcmaster.com/6529k42 )
(3) Use a 1/4-20 die to thread one end of the shaft stock
(4) Tap the 1/2" hex shaft
(5) Press-fit the gear onto the non-threaded end of the shaft stock
(6) screw the shaft stock into the 1/2" hex shat. Locktite.
Ours is not a high-torque application, so I’m not terribly worried about the shaft coming unscrewed.
Please throw stones. I’d be happier if I could just find the hex bevels in stock. We don’t have a lathe, so just turning down the stock until it press-fits into the gear isn’t an option.
A drill right angle adapter might work for you. Plus McMaster has 1/2" hex with 1/4" hex ID.
We wrote up a blog post this fall about this,
33 has an intructable about the same idea.
With the cost increase of the miter gears we didn’t get as many in stock as we wanted for this season. We have a few more on the way, but probably not enough for everyone.
-Andrew
We just use an 030 endmill to take out the corners and then machine the hex. There no contact on the corners but it doesn’t matter. With hex shaft all of the load goes through the flat portions so losing contact in the corners is not an issue
You’re probably fine with this method for many applications, but strictly speaking that isn’t true (that the corners don’t carry load). With a tight slip fit, any portion of the assembly in contact is going to carry load. You can reduce some contact in the corners (as your solution does, or as ThunderHex does to a much smaller extent), or you can reduce contact in the centers (as AM Churro extrusion does), and in lower load applications either will still work - it is a function of the tightness of the fit and total contact patch, not precisely where that contact patch is.