We've had a pretty productive week so far! We're making good progress on two of the beetles, have one 'bot done, and are really waiting for parts to show up to get cracking on the others we're planning on taking to Motorama 2012. While we wait for those parts we have some pieces we can make ourselves, and we still have the wiring to do on Unlettered Understrapper 2.5. Hit Back after viewing an image.
We set Milly off and running on the remaining aluminium parts for the featherweight. While that was going on we decided to finish the lifter for the beetle. We've drilled and tapped one hole for the crank, to fit a #6-32 1" screw which will be Loctite'd in after assembly.
Looks like Milly has finished - we have the three aluminium wall pieces and a spare for each. Still some drilling and tapping to do, once the top and base plates show up.
With the aluminium done, we set Milly off on the UHMW wall pieces, and went to go find something else to do.
Here we've bolted in the crank for the beetle lifter. We still need to round off the ends on the sander, but it's looking okay so far.
A bit more drilling and tapping and the rocker arm has gone in place. Again we need the edges rounding down, but it's coming together nicely.
For fun, we decided to put the arm into place in the 'bot, using hex keys, and the holes all line up, so yay! :-)
Here's where the arm extends to, give or take, and it ought to be enough to be able to fall to one side and roll on to the wheels again. The only issue is that cranking the arm takes a bit of force, and we're not entirely sure whether the HD servo we have is up to the task. We'll have to see when the 'bot is a bit more assembled. We can always switch to a gearmotor, and figure out limit switches using a Team Delta relay.
Yay! The UPS guy just dropped off a fairly large box - let's see what's inside!
Parts for Formidable Fustigator 2.0: base plate; top plate; and boom strengtheners.
Parts for Poor Punctuation 2.0: top and bottom plates for a one-weapon-motor configuration; top and bottom plates for a two-weapon-motor configuration; a pair of UHMW rings; and titanium weapon ring and gears.
Parts for Malicious Mule: top and bottom plates; inner walls; spare outer walls; front and back plates; and aluminium outer walls.
Parts for Didactic Duelist 1.5: base plate; top plate; side walls; wheels walls; engine mounts; rear walls; and side walls.
We couldn't resist: we had to do a little on the antweight parts! Here we've drilled the UHMW rings slightly to accomodate #4-40 locknuts.
And with minimal effort the locknuts have been pressed into place. We had originally envisioned regular hex nuts, but inexplicably we don't have any, hence the locknuts.
Here's how the antweight parts stack together - polycarb, UHMW ring, titanium weapon ring, UHMW, and then polycarb. There will be a bunch of spacers holding everything together.
Meanwhile, Milly is still turning away on the UHMW parts. Because even half-inch thick UHMW is a bit bendy, we're only doing four inches at a time - the width in the vise, to ensure that at least that much doesn't flex while we're cutting.
Here's the front wall for the 30lb'er, and it's 26.5" long, so we're having to work around the lathe chuck to be able to get the middle of the part, but we finagled it successfully.
Here's a test-fit of the 30lb'er walls on the baseplate. If you look at the back wall, it's not sitting on the baseplate, so obviously we messed something up. On closer inspection we mis-measured the length of the side aluminium walls - they should be a quarter-inch shorter! Thankfully that'll be pretty easy to take care of tomorrow, so we've put it on the list of things Milly has to do tomorrow.
A quick trip to the mailbox yielded junkmail and a package from Hong Kong - more spiral bevel gears! We were planning on using these on the 30lb Sportsman Walker Cyber Scorpion 0.9, but we've scrapped that idea - just too complex with not enough time for Motorama 2012, but on the plus side it'll be a project that will keep us engaged in 'bot-building through the year, rather than just the few months leading up to Motorama 2013 ...
Here we've already counter-sunk all the holes for the top and bottom plates for the antweight's two-motor configuration, so we're about to throw some team colour on them, while we fiddle with some other parts ...
... Namely the antweight weapon motors. They came with set screws in place for prop-savers, but by golly they were in there tight! We ended up Dremelling them off.
Right - we've taken the can off one of the motors intending to press the titanium ring onto the can!
Er - yeah ... not so much. We've mangled the can pressing the gear on, so something's obviously not right here. We broke out the calipers, and groaned. For a press fit you typically aim for three or four thousandths difference in size. What we have here is four hundredths difference. Grr. Our bad on the DXFs we sent to the Whyachis, so what can we do about it?
We set the Dremel-a-like onto it and see if we can neatly take the inner diameter of the gear to somewhere close to the motor outer diameter. Unfortunately we got far too carried away - not realizing the Dremel-a-like worked so quickly on Grade 5 Titanium, and now the ring just slips down the motor. Drat!
At this point we have one good motor, one bad gear, and two fresh gears. Obviously we're going to have to order some more motors, but we started wondering whether we could reclaim the bad gear some way, so we built a jig ...
... And applied some Loctite to the motor/ring combo. Ordinarily we'd have used duct tape, but felt this operation needed a little more finesse. The jig has the ring 0.25" from the bottom of the motor, so if this works we have one working weapon motor. We'll find out in the morning whether we were able to save the titanium gear.
But the first thing we have to do tomorrow is clean, tidy, and organize the
garage Build Space, because we wasted a whole heap of time today simply trying to find things! This place is a bomb site hit by a tornado! So that's the plan for first thing tomorrow. For now, we're going to have a gin and tonic, and order some motors ...