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BrainStrain wrote: »
Grins or grimace, upside down numbers are now part of the tale. My current project has seen a couple of new parts due to fabrication mistakes, but the worst mistake I ever made was 15 years ago on a wood-working project. I was making a two-drawer lo-boy dresser. The front legs had 5 mortises and a taper. The outside edges had to be rounded over on the router table, so I picked one up and promptly rounded over the wrong edge. That was a 10-hour mistake. I hope not to set a new mistake record in the future!
photomankc wrote: »
Man that thing is huge! If there is a Sarah Conner in your area of operation it really is imperative that you send it to visit her when it's working.
DiverBob wrote: »
All six legs are put together and I have one mounted on the body! I created 3 spacers for each leg to position the leg thrust bearings correctly. That went pretty quickly in the new lathe. The lift motors are not installed yet, because the location where the wire comes out of the motor housing is in a different location than the original motor, it rubs against the strut on that side. So I need to come up with a different way to route the wires by drilling a new hole in a different location. As I was typing this I thought of another option, carefully cutting off the metal casting protrusion holding the plastic piece the wire comes through and putting a small rubber grommet in its place. Hmmmm, Need to check that out....
I'm working on the remaining 5 gear reduction units. There is a steel shaft that has press fit tolerances for the gears to be created and the gear motor output shafts have to be machined. This requires dis-assembly of the gear motor and then carefully mounting the output shaft in the lathe. The shaft is then turned down to 0.2505 diameter for a press fit along the main shaft and 0.2495 diameter for where it passes through the bronze bushings.
I have to see how much I can get done this week, my schedule is pretty full plus getting ready for a big dive next Sunday.
vanmunch wrote: »
Looking good. It will be worth a trip to what ever expo you bring it too. BTW I see the McMaster-Carr bag your secret sauce is out!:)
photomankc wrote: »
Bob, you might consider a tight slip fit and loc-tite rather than a true press fit. Gives you a bit more leeway between perfect and scrap. Gear to shaft may have too much leverage for that if it's a big gear but a small one is not going anywhere once that cures. I use green loc-tite on bearings now almost exclusively. I don't spend forever trying to shave just the right 1/10 off the bores anymore. +.0005 to 002 is good enough and that bearing is going nowhere unless you put a torch the thing to break the bond. I always have mixed luck with those critical fits on these small machines sometimes they just don't want to cut as you try to sneak in on it and then they suddenly bite and take too much,
Kudos though if you do it the manly way!
erco wrote: »
Learn from the Corvair guys. If you want to lock a gear to a shaft, use two setscrews on the circle: http://corvairmechanic.com/IMAGE005.JPG
erco wrote: »
OK, then use two hardened 1/16" dowel pins with Loctite on that 1/4" shaft. Still beats making everything all over again!
garyg wrote: »
This is the longest running forum thread I've ever seen.
Every day, I look for new updates from you.
You are doing a fantastic job at updating and laying out your experiences.
Thanks and keep it up.
ratronic wrote: »
Bob I have been looking at this thread off and on since you started it. That last video was impressive, it is now gaining some mass. I like other's appreciate the fact you have taken the extra time to document your build here. Have you estimated the final weight including batteries?