We're reallllly close to having the Sportsman finished, so our goal this evening is to finish the 'bot and cross it off the To Do list. We only have a few things to wrap up, so fortified by a home-made pizza, it's time to hit the Build Space! Hit Back after viewing an image.
Issue number one is that we ended up with two different lengths of chain for the weapon transmission, which means something went awry here. After looking at it, we think we installed one of the weapon motor mounts upside down - they're not symmetrical.
So over to the drill press, and we put a couple of new holes in the mount after carefully taping up the motor so we don't get polycarbonate chips in it.We'll spare you the tapping photo :-)
With the mount reinstalled we took a moment to test the spin direction of the motor, and labelled the extension wires accordingly. We want to make sure the saw blades spin in the right direction after all.
We also took the bolts out of the polycarb mounts for the second and fourth mounting points, allowing them to essentially act as spacers, and that definitely helped eliminate some of the friction in the setup. As you can see in this photo we have grease on the the front panel and DeWalt mount, indicating it spun up, and we have [loud] video to prove it:
Success! There's still a little hesitation in the initial spin-up, but not enough to worry about - one half of the weapon is running finally, so it's on to the other side. We removed some of the bolts there too, and verified that both sides spun up at the flick of a switch on the transmitter. Hurrah!
And there we have it: a little over a year after beginning this 'bot, our first ever Sportsman class 'bot is complete: Palindrome30. This is going to be a really fun 'bot to play with, we can already tell. The weapon arrays may not be particularly effective when all is said and done, but it ought to be pretty durable, and hopefully we can keep it running long enough to win at least one match with it.
As you can see, weight is not at issue, at 26.2lb, but you'll also notice the 'bot sits nicely on it's side. This could be an issue, so with the remaining weight we're thinking we should cut some aluminium angle and bolt it to the sides to prevent it from sitting on the edge.
We also have a mild drive train problem to deal with - the keystock we put in is too small for the driven axle and the sprocket falls off. To fix this we need to disassemble the drive train and add a larger length of keystock. We took the side off, but notice the issue? The Nutstrip stops us from removing the wheels, so that had to come off too.
Here we're in the midst of reinstalling the sprockets, and while we're at it we added a couple of roll pins too, to ensure things stay nice and snug. So there we go, everything's been crossed off the To Do List for this 'bot, and 60% of the fleet is ready for Motorama 2013!
We still have a couple of hours left this evening, so it's time to change tack - from the biggest 'bot to the smallest, and we're working on Lauren's fairyweight Tenacious Tinkerbelle. We started with a weight check, and scared ourselves when the scale read 153 grams - before discovering there was an extra battery pack inside the chassis! With that put aside the 'bot weighs in at 140 grams out of the 150 allowed, so no worries there.
Tonight's efforts are mainly in the soldering arena - never our favourite occupation - so here we have the materials: the drive motors, which need extension leads added, and connectors for the batteries to make them compatible with our chargers.
Soldering the extension leads actually wasn't too painful. We did take the time to 'tin' all the ends, and that definitely helped when it was time to actually stick them together. We even went for some shrink wrap tubing to hide the evidence of the ugly soldering :-)
With all the extention leads done, we drilled the wheel hubs to 7/64" which is a hair under three millimeters, and pressed the wheels onto the motor shafts, then installed the motors back onto the base plate.
Whoo-hoo! UPS just came and dropped off a heavy, flat package. We quickly unwrapped it, and found this: the 1/4" 6061 aluminium plate with all the parts for the combat version of the hexapod walker - in order to save time and be able to ship this to us for the weekend, we asked Jake over at Westar Manufacturing (Team Whyachi) to leave everything unsnipped and unsanded - we can do that ourselves, and the resulting piece of waterjetting looks fantastic!
Anyway - back to the fairyweight. Here the receiver has been plopped into place on a piece of double-sided foam tape. We need to corral all the excess wire, and hook the speed controllers to the wheels and the battery, preferably incorporating the demo FingerTech power switch as we go.
Sorry for the blur - we were moving fast :-) This was supposed to be a shot of the new connector being installed to the battery so we could hook it up with the connectors we had lying around, rather than making a special purchase. We have two batteries to modify, and it doesn't take too long.
Here's a close-up of the FingerTech power switch with leads soldered to the tabs. It's actuated with a 3/32" hex key - clockwise for on and counter-clockwise for off, which is the reverse of the Whyachi power switches we're accustomed to, so we'll need to make a mental note of that.
Mid-way through the soldering, and things are going well, but there is a awful lot of wire to cram under the lid in this 'bot - we may have to add a few micro-sized zip ties to help keep things organized.
We're almost done - we have one side of the drive train soldered up to the ESCs, and the ESCs soldered to the wiring harness to connect to the battery. A few more connections for the other side of the drive train, and we'll be about done.
Ta-daa! Everything's been soldered together. We do need to drill a couple of holes in the back wall and mount the power switch properly, because the foam tape isn't holding up to screwing the switch on and off. We fired up the transmitter and calibrated the speed controllers, so that was a pretty good indication that things are soldered together properly.
A final piece of soldering for the night is in making a charging cable for the 'bot's battery. These batteries won't be balance-charged, but then again they're under five dollars apiece, so essentially they're considered disposable - if they can't take being charged regularly, we'll replace them.
Finally it's time to wrap up for the night. As you can see from the To Do Lists we've made quite a lot of progress - Lauren's fairyweight is ready for a test drive, we have a couple of tweaks to make to the other insect-'bots, a drive train to repair on the drumbot, a drive train to build for the featherweight, and a walker to assemble in the beetleweight category. Sounds like a lot, but we still have two weekends to go, so this ought to be eminently doable!
Tags: build, fairyweight, sportsman, teti, pal30
We got a late start tonight, but really wanted to make more progress on the Sportsman Palindrome30 as it's the next 'bot closest to being finished, and one that we have everything we need for. Hit Back after viewing an image.
There are essentially three things to do: (1) Finish wiring the weapon speed controls; (2) Fix the slipped keystock in the drive wheels; and (3) Eliminate the friction from the weapon axles. We started with the wiring, and with a prodigious number of ring terminals, hooked up all the weapon ESC-to-motor connections. They tested fine, despite the weapon axles not actually spinning.
As it's getting late, we don't want to start disassembling the weaponry and drive train right now, but to all intents and purposes this 'bot is about ready! The wiring fits nicely in the chassis, which is something that hardly ever happens first time out.
A parting shot of our To Do Lists. Walking beetleweight aside, there's not a whole lot to do as we come down to the penultimate weekend before Motorama 2013. There's some troubleshooting on the Sportsman, drive train assembly on the featherweight and 12lb drumbot, soldering for Lauren's fairyweight, and a little troubleshooting on a couple of the small 'bots. The plan for this weekend is to have all the 'bots except the walker finished, leaving all next week and weekend to work on that one, as it's the most complicated.
Tags: build, pal30, sportsman
We knew the moment we woke up this morning that we were finally going to receive our fancy new parts from FingerTech Robotics (despite obsessive refreshing of the USPS tracking page not showing any updates) and we wanted to finish another 'bot tonight. Things had stalled a little in our timeline, although things were getting crossed off the To Do Lists. To the Build Space! Hit Back after viewing an image.
Three TinyESCs (two for Lauren's fairyweight and a spare), two prototype power switches (one for the same fairyweight and one for the beetle Belligerent Battler 1.1), and ten - count 'em - ten custom urethane wheels (two for the hobbyweight drumbot, five for the featherweight brick, and three spares). They're Shore A45 hardness, which is actually softer than Colson wheels, and in theory a bit grippier, so we'll see how they perform. Thanks to Kurtis over at FingerTech for getting these to us!
Here's a test-fit of one of the wheels. They're a larger version of sumo wheels, and as such they're open on one end. It took a while but we figured out what we were going to do: turn the wheel around so the closed end meets the hub of the gear; drill both the gear and wheel hub for four #6-32 bolts to couple them together; order some 1.25" OD plastic from McMaster, and when it gets here, cut some 1" lengths, bore them on the lathe, and insert them into the aluminium hubs. We don't see what can possibly go wrong :-)
Despite our enthusiasm, we're going to have to wait on further featherweight progress, it seems, until the McMaster order shows up on Friday. So let's turn to the Sportsman Palindrome30 instead. The last report we put up on this 'bot received nineteen Facebook Likes as of writing this report - we have no idea who all those people are, but thanks! First up today, we drilled and tapped the weapon motor mounts.
And they came out quite well - we did manage to bore one mounting hole while running a drill bit part-way down to recess the bolt heads, as the part 'jumped' up. Still, pretty good show.
We have a piece of 1/2" outer diameter aluminium round pressed on to one motor shaft, but when we attempted to press the sprocket onto the round, all we achieved was to cause the motor to lock up. After unjamming the motor, we decided to turn down the round a little, so we hooked up the weapon power, turned on the radio and receiver, and flicked the gear switch to activate the weapon motor.
After applying a file to the running weapon motor for a little bit, we were able to push the sprocket on successfully. The other motor had already been successfully installed with round and sprocket.
Although it's not recommended, we're going to be using set screws and a little LocTite blue to secure the sprockets on the aluminium rounds. At this point, we're ready to install the weapon motors in the 'bot and think about coupling them to the weapon axles.
In order to power the weapon motors we're going to need a 4S LiPo battery and some speed controllers. We're using cheap HobbyKing 60A ESCs we had laying around, and a Turnigy battery pack. Remember the goal is to not have to buy anything special for this 'bot.
Zac O'Donnell gave us a great idea for getting the weapon blades pinned - genius in its simplicity: Take a piece of 1/4" keystock, drill a short hole in the end big enough for the roll pin to sit in, then hammer the keystock to seat the pin, because we can't get the hammer close enough to the pin itself. Thanks Zac!
With all the weapon blades pinned, we moved on to the transmission, which is #35 chain. Why is it chain always needs an offset link?! It's been a while since we used a chain breaker, and in the end went back to how we cut #25 chain - Dremel off the top plate - because the chain breaker was leaving us with warped top plates on the next link.
The weapon transmissions are in place, so we now need to move to our least favourite part of 'bot building: wiring. We started by attempting to solder bullet connectors onto the two weapon speed controllers. It did not go well. Despite our best efforts: tinning wires, using the helping hands gadget, etc., we ended up frustrated.
So out come the ring terminals, of course. Here we've installed ring terminals on the two speed controllers, and our next move is to do the same with the weapon motors. We'll need some extension wiring between the motors and ESCs to let us put the ESCs where we want them, but that's not a big deal.
The ring terminals are on the weapon motors, and we begin to wire them up to the power switch. We decided at this point it might be worth testing to make sure we're getting this right. The weapon ESCs don't have a battery eliminator circuit (BEC) in them, so in order to test, we'll need to turn on the drive power too, which has a dedicated BEC on it.
Drat. With some temporary wires in there and the power on, there's too much friction for the weapon axle to spin up. We tried both front and back axles, and they both have the same issue - no doubt because we're using aluminium round in bronze bushings, and the round may be slightly oversized. It's getting late, but we're going to have to do two things when next we build: (1) Finsih the weapon ESC wiring; and (2) disassemble the weapon axles so we can sand down the aluminium axles where they sit in the bushings. The other thought that we had, which may eliminate the issue, but adds time to the equation is to replace the aluminium axles with steel, which are more likely to not be oversized. For now, though, we're going to try the sanding route, and see where we end up. Hopefully with one more productive build session like this evening was, this 'bot will be done!
Tags: build, pal30, sportsman, featherweight, ii3
Having had fun with our new lathe yesterday, we decided to put some effort into our other big 'bot - the Sportsman Palindrome30. We need to get the drive train wrapped up, which means installed and chained up. Then there's the weapon and wiring. After fixing up some work issues, we finally headed out to the Build Space. Hit Back after viewing an image.
In order to get the drive train into place, we need to mount some home-made bearing blocks. Here we've drilled the mounting holes, and also 'countersunk' them with a larger drill bit, as we don't have a countersink with a 3/8" shaft, and the 'bot wouldn't fit on the drill press as is.
As it happened though, we had to take the chassis apart, so yes, we could have countersunk the side walls, but moving on - here we've verified that the total width of the axles and bearings is the requisite 2.75". Time to mount the bearings!
They may be ugly, but they work! It didn't take too long to mount all four outer bearings and Dremel-ish down the bolts. So then the next step is securing the drive sprockets to the axles.
For this we cut four very small pieces of 1/8" keystock with the Dremel-ish, and finagled the tiny pieces into place on the shafts. Everything is looking pretty good at this point, so we moved on to chaining the sprockets together.
Rummaging around, we found some random length of #25 chain, and strung a piece across the first side of the drive train, marked where the connecting link should go, and then ground off the link with the Dremel-ish. A bit more rummaging around turned up a couple of #25 master links, and one side was ready to roll.
Here we are with the first side installed. Next we need to mount the inner bearing on the inner rail before we can get too much further, so it's over to the drill press, which didn't take very long at all. We're getting excited - we might actually be able to get this 'bot moving today!
Another random length of chain being cut to size. The amount of junk we have lying around is pretty astonishing - aside from the black UHMW, we actually haven't bought anything specifically for this 'bot - it's all stuff that we have laying around the build space. Granted, we only have more more Victor 883 speed controller left, but if push comes to shove, we can swap in a BotBitz ESCheap85 to run the DeWalt on - we're not messing with gyros in this 'bot, so the incompatibility won't be a problem.
Ta-daa! The drive train has been assembled. Next we want to add some wiring, batteries, and a receiver, and see if the wheels will spin. There are two power switches because the drive and weapons run at two different voltages - 6S (22.2V) and 4S (14.8V) respectively. We ought to be able to wire up the drive, and not have to make any wiring changes later when it's time to wire up the weapon.
Before wiring, we reassembled the chassis. The 'bot bears a tiny resemblance to its inspiration, but is distinctive enough to stand apart from it. We're happy with it thus far :-)
Time for a quick weight check - with all the parts and pieces piled on, the 'bot weighs a scan 25 pounds even. No worries about making weight here then - just like the featherweight we don't seem to be able to use up the entire allotment this time around.
Success! We didn't take any video, but after plugging a battery into the drive wiring harness the receiver was able to bind to the radio, and we made the wheels work! It took a little bit of channel reversing to get things turning in the proper direction, but after a few minutes of fiddling the 'bot drove under it's own power. Then we lost two wheels. Apparently we're going to need a bit more keystock in those sprockets to keep everything engaged - no matter, that's a pretty easy fix. All told, we're in a good mood, and we're looking forward to wiring up the weapon tomorrow!
We decided to capitalize on our productive spurt, and cut and crimped connectors on all the drive motors for the featherweight Intrusive Interloper 3.0, using the one drive pod we assembled the other night as a reference point.
Finally for tonight, we also put connectors on the remaining speed controllers, so there's one less thing to do when the wheels show up and we can do some final assembly on the drive pods! All in all, a pretty productive day :-)
Tags: build, featherweight, sportsman, ii3, pal30
We have a bonus build day today, as our day job closes to observe Martin Luther King day, so it's out to the Build Space to see if we can cross some more items off the To Do Lists. We're going to focus on the two biggest 'bots today - the featherweight Intrusive Interloper 3.0 and the Sportsman Palindrome30. We're a bit stuck on the drive train for the Sportsman, and pretty much out of parts for the featherweight, but we'll see what we can do! Hit Back after viewing an image.
Ah, the mighty To Do Lists ... they keep us on track, and provide much enjoyment when it comes time to cross something off. If you look closely, you'll see there's actually a couple of items for 'completed' 'bots, but we save small tasks like that for weeknight build sessions so we can maximize the daylight time for marking, drilling, etc. For some reason, it just seems to come out more accurate in sunlight ...
Speaking of accurate drilling - it's time to do some. Using our CAD model of the featherweight, and knowing the mounting holes for the drive motors are 25mm apart, we marked and drilling one of the drive pods and test-mounted the motor. Came out well.
Well enough that we went ahead and drilled and mounted all the drive motors. The all seem to be pretty darn accurate, so that's good. Now we wait for gears, wheels, and speed controllers.
Some more accurate drilling later and we can actually mount the drive motors for the Lauren's fairweight - they're a bit cramped, but they fit, so that's good. We have a battery and a receiver for this 'bot, and we just need a couple of speed controllers.
Turning our attention to the Sportsman, and one area we've been stumped is the drive train - never exactly our speciality by any means, but without a decent lathe (sorry Milly) or even a broach any more, we can't make new ones to fit these 6"x1.5" Colson wheels. Instead we decided to get creative. We started with the pre-made hubs used in the last dismal version of Steel Stiletto. They're not long enough to go through the entire bore, but they're a good start.
Then we broke out our parts bins, and started looking for things that would help fill up the bore in the wheels, yet accomodate a keyed 1/2" shaft. We were willing to take any combination of bearings, bushings, washers, and shaft collars that would work!
While we were fiddling around trying different combinations of the above, UPS dropped off a package - gears for the featherweight! And a bonus LED light - handy. In the foreground are the 12-tooth 32 pitch steel gears; they have a 3/16" (0.1875") bore, and the drive motors have a 5mm (0.1969") shaft, so we're going to need to figure out how to enlarge the bore to fit the motors. In the background we have the 54-tooth gears that drive the wheels, and their 3/8" bore will need to be enlarged to a half an inch at some point. When the wheels arrive, we'll decide whether to go get the gears broached for a keyway, or whether we want to mount the gears to the wheels themselves with bolts.
Back to the Sportsman, and we need to fix the saw blades to the shafts and cut holes in the front and rear walls for the weapon chain. To that end we removed the front wall from the 'bot to make it easier to work with. We never created a CAD model for this 'bot, just started winging it a while back, and made a few poor decisions along the way, which is why the weapon axle mounts overlap the bolts that secure the front wall to the inner rails - oops.
We broke out the Dremel-ish and ground flats into the aluminium axle to make drilling the pin holes easier. It was a bit cramped in the outer spaces, but still relatively trivial to do.
In a moment of inspiration, we figured out the mounting solution for the Colson wheels! They have a 1-3/16" bore diameter, and in addition to the bits of axle core we retrieved from the former hobbyweight, these 1/2" shaft collars have an outer diameter of 1-1/8" so with the addition of a circumference-worth of double-sided sticky foam tape, they pressed in nicely! We're going to pin them through the tire too, but we have a solution!
Ta-daa! With some nylon washers, we're able to run chain pretty smoothly on the sprocket, and the whole solution fits the two inches across that we have between the inner and outer rails. There's still pinning to be done, and we need to put a tiny piece of keystock in each of the sprockets.
But hey - we have a workable solution, and quickly have all four wheels mounted on makeshift hubs - they're also much less wobbly than the ones we previously had in Steel Stiletto, so that's a bonus! Mounting the tires had been a major sticking point, so we're really happy to have this problem licked :-)
Back to the weapon assembly, and here we've drilled the pin holes for the 1/8" roll pins, but then realized that the one inch long pins we have we going to be far too awkward to hammer in, as there's only an eighth-inch of clearance beside the saw blades. We're going to have to order some longer pins and then Dremel-ish them off after inserting them.
While we had the walls off, it was an opportune time to cut holes for the weapon chain. We started by drilling some 3/8" holes in the corners, then broke out the jigsaw to finish them off. Fairly quick and painless to do.
So here's where we're wrapping up for tonight - we need longer pins for the weapon array, then those will be done. We need to drill the side walls for the drive bearing blocks, and install the drive train. We need to drill and tap the weapon motor mounts, and install those. Then it's a matter of wiring the 'bot up, and taking it for a test drive. With any luck we'll finally have this 'bot done by next weekend!
Tags: build, sportsman, featherweight, ii3, pal30
For whatever reason we didn't take very many photos today, but we did get some work done. We wanted to tidy up the carcas of our previous fairyweight, contemplate an alternate fairy, and make some progress on the Sportsman. Hit Back after viewing an image.
We pulled four mystery Pololu-style motors, with wheels, and they weighed 2 ounces. A fairyweight is allowed 5.3 ounces, so it could be feasible that we could build an indestructible fairyweight version of Intrusive Interloper for Motorama, but really that was just fiddling. We did disassemble Transcendental Terror 1.0 and clip out the juicy internals. All told, the motors, weapon, battery and wheels came in at 90 grams, which is what we expected, so with the titanium and UHMW chassis components to come we should be fairly clean sailing to making weight.
The other 'bot we spent some time on today was the Sportsman Palindrome30 which is coming together nicely. We fixed up a pair of dead DeWalts with replacement motors, and installed a pair of Victor 883s from our featherweight - it'll be going brishless in the next version, so we have the Victors to spare - and installed those too. The power switches are installed - 4S LiPo for the weapon and 6S LiPo for the drive.
At this point it was time to wrap up, and go clean up for dinner, but with any luck the parts for the fairyweight will come by next weekend, and we can wrap up that build stat!
Tags: build, fairyweight, sportsman, tt2, pal30
It's been a while since we stepped out into the garage Build Space, but it's coming up on the end of November, which means Motorama 2013 is not that far away and we have 'bots to build! The game plan is to try to finish as many of the fleet upgrades as possible before the end of the year, so we can focus as much of January and February as possible on our beetleweight walker Hexapedal Hitman 0.9. Guess we'd better get a bit of a move on! We've placed orders for parts and materials, so while we wait for those to show up, we decided to see what we had available to work on. Hit Back after viewing an image.
The last time we were out here, we left scratching our heads as to why Steel Stiletto wouldn't power up. After checking all the other parts, we decided to check the power switch. As you can see here, we must have gotten over-enthusiastic turning the 'bot off at some point, and bent the copper bar inside the switch, such that it wouldn't connect - oops! We flattened it back out, and reassembled the switch.
Unfortunately, during the process of wiring the 'bot back up, we somehow managed to short one of the speed controllers by touching a ground connection to the metal heatsink on top of the unit. Drat! This means having to swap it out, and swap a fresh one back in. The only spare we had was one of the ones we hacked ourselves.
Which did not go well. Oh well ... we have a couple of pre-hacked ones on order, and will swap them in once they arrive, and maybe finally we'll get to try out a gyro in this 'bot. Moving on ...
We dusted off the chassis of one of the beetleweights we started a while back, and played a little with mounting some internal components, before realizing that we already have two working beetles, plus we're going to be building the walker, so there's no room at the moment for this 'bot in the fleet, and therefor no need to spend much time on it. Moving on ...
Next up, the Sportsman class Palindrome30. We took the parts with us to Motorama 2012, which was pretty foolish, because there was no way it was going to be completed in the pits. But at the moment we have time, and most of the parts already in hand, so we put some effort into it.
We're using 6061 aluminium round for the weapon shaft, but it's oversized and we can't get a sprocket on it, so we opt for the Poor Man's Lathe, and chuck the round into the drill press, and hit it with some sandpaper. It took a while, but eventually we had the round down sufficiently to be able to work the socket on.
Ta-daa! One end of the 'bot - not quite complete, as the weapon blade hubs have not been pinned to the axle, and we need to drill a couple of holes for the weapon chain, but pretty close!
Here's the end bolted into the chassis, and looking about how we had it in our mind's eye. We're working without CAD for this 'bot, which is unusual, but also somewhat liberating, and it's a fun 'bot to work on.
After repeating the lathe process with the other weapon axle, we were able to bolt together the rest of the chassis, and here it is!
The next step will be to install the drive train, and then move on to the weapon motors, and finally the electronics. Here we're testing drive shaft lengths, and our home-made bearings. Things seem to fit quite nicely, but we've hit a stopping point for today for two reasons - we don't have any wheel hubs for the 6" Colson wheels we're using, and we're headed to the movies to see Skyfall!
Just for fun, this is what the fleet looks like in the Build Space - ants and beetles on the top shelf; beetle, hobby, and sportsman next shelf down; feather and hobby on the next shelf down, and finally misc parts on the bottom.
Tags: build, ss, hobbyweight, sportsman, pal30
Two build days and two unfinished 'bots. Not much introduction to this one, just get out there and get some construction accomplished. We did start by revising our To Do lists for Formidable Fustigator 2.0 and Palindrome30; unfortunately there seems like about three days of work to do - missing Tuesday and Wednesday evenings has hurt the schedule, but we'll see what we can do. Hit Back after viewing an image.
First up today is another trip to Chris Allison's place for some sawing and lathing. Lots of small, but vital parts.
The bandsaw makes short work of our list of things to cut - some weapon motor spacers, weapon shafts, blade hubs, and transmission shafts.
And over to the lathe for some boring and turning, not just of the pieces we cut, but a pulley and some bushings too.
Here are some blade hubs - these will be drilled and screwed to the blades, and the hubs will be pinned to the weapon shaft.
Not a bad couple of hours of work. We'd like to say Thanks again to Chris for his hospitality and his very cool workshop - incidentally, Chris runs a pretty neat web site with all sorts of cool industrial and machinery stuff for sale.
Back at the Build Space we're drilling the saw blades and hubs. Thankfully these blades didn't put up too much of a fight, unlike the gears the yesterday.
We also had a couple of wheel hubs left to broach, which we just about accomplished, but we broke our 1/8" broach during it, so when we get back from Motorama we'll have to hit eBay for a replacement.
The wheels and hubs have been drilled and tapped for a 1/4"-20 bolt to hook them together, and it's nice to be able to check something else off the To Do list.
We weren't able to line up a welder to stick the gears to some spacers, so we decided to go with a great idea Jason of Team Terror came up with - slot the gear, and put a pin through the shaft to keep it in place. Slotting the gear was easy enough ...
... But drilling the motor shaft was nigh impossible, so we slotted that too! Seemed to work fairly well, with the aluminium spacer in there too.
We've switched the orientation of the shaft on the two motors for the Sportsman, like we did for the Featherweight. We've also pressed on the aluminium spacers for the sprockets, which we'll drill and tap for a small set screw where the Xs are.
Here's the weaponry for the Sportsman - eight saw blades, four for each end of the 'bot, with their hubs installed, and ready to be installed to the shaft.
Now that we have the pinion gears mounted we're able to figure out that the motor mounts need to be one and 1/16" from the center of the transmission shaft, and the bevel gear needs to be 0.3" up from the baseplate, for optimum contact. Once we drill the bushing and mounting holes in the top and bottom plates, we'll be ready to install the transmission, which will just leave wiring on the thirty pounder.
We hit the wall tonight, and decided to go do some laundry and have something to eat, leaving To Do lists with quite a few items on them, but actually a lot of these remaining steps are all dependent on one or two key steps, so if we can get them done tomorrow morning, the rest of the 'bots should fall in place. In reality, we're not 100% sure that both these 'bots will be finished tomorrow ... worst case we'll be doing some wiring in the pits on Friday ...
Tags: build, featherweight, sportsman, ff2, pal30
We only have three days of build time left before hitting the road for Motorama 2012, and we still have two unfinished 'bots. Today we decided to concentrate on the one that has the most work to be done: Palindrome30, our Sportsman-class thirty pounder, and see how far along we could get. Hit Back after viewing an image.
We're starting out today with some disassembly, as we need to be able to get the baseplate drilled for motors, etc. There are a lot of bolts on this 'bot! But thankfully only eight to be able to get at the batteries.
We've ended up using buttonhead bolts for the outer blade brackets, because we couldn't get the countersink into the groove to be able to use flathead ones, so we need to make recesses for clearance. As the side panels are 15" long, we can't do this on Milly, but we can put a half-inch endmill in the drill press and get the job done.
They actually came out quite well, once we got the hang of shimming the wall in the slot on the side of the drill press table. One more thing to cross off the list.
This was a test to make sure the clearance holes were deep enough - it all looks good, so time to move on to mounting things on the baseplate.
But first a weigh-in. Despite the copious number of bolts in this 'bot, we're still way underweight at the moment at 26.0 pounds. Granted we do need to throw in eight hubs for the saw blades, but they're only going to be πr2 x l x density, or 3.14 x 0.625 x 0.625 x 0.375 x 0.1 = under an ounce each.
After marking and drilling the baseplate, we have the DeWalt drive motors in place. We also drilled mounting holes for the weapon motor mounts.
It's pretty chilly again today, and we had the heater running, which did a good job of warming things up, but this also warmed us up: forcing an 1/8" broach through a wheel hub - darn, that was hard work! Two down, two to go, and we'll come back to them in a bit.
This shot was taken after carefully tightening the weapon brackets, and getting them all aligned. The shaft actually spins fairly freely, which is great!
On the internals, and here's a test layout. It's fairly cramped in here, but that's a good thing - it'll stop components from bouncing around inside the 'bot. On each end we have a weapon motor and drive speed control, next in are the drive motors, and in the middle we have a 4S weapon battery, two weapon speed controllers, and two 3S drive batteries which will be linked in series for 22.2 volts. There are two separate power switches, one for drive and one for weapons.
The two power switches have been mounted to the side wall, to get the hex hole as close to the top panel as possible, and leave room underneath for wires to pass by.
The top plate has been drilled for access holes to the power switches. We're not going to paint the top, so the LEDs on the Victor 883s will serve as our power lights, saving us from having to cram another component in there.
The drive ESCs have been mounted, and we're beginning to wire things up.
We didn't pay attention to the batteries when we selected them, but these packs have 8 gauge wire on them. We don't have any connectors that fit that size of wire well, and after struggling to get Anderson Power Poles on one of the two packs, we finally gave up for the night, intending to mull over what sort of connectors we can use, and come back tomorrow with a solution!
Tags: build, sportsman, pal30
Time's ticking away, and we still have two 'bots under construction. We had some errands to run this morning, but at lunch time we bundled up warm and headed out to the Build Space. There are a number of key things to be done, and with a McMaster delivery last night we ought to be able to make some decent progress. Hit Back after viewing an image.
Speaking of lunch - this is a left-over slice of pizza we made last night - Five cheese and Jalapeno Sausage - very tasty :-)
Some of the parts we received yesterday included some aluminium spacers and a 6mm drill bit, so we drilled out the spacers for the featherweight's weapon motors, to take them up to the 8mm bore of the pinion gears.
Two drill bits and half an hour later and this is as far as we'd gotten drilling holes in the pinion gears. These gears must be hardened, as they're proving to be a bear to work with. We're going to have to think up an alternative method of securing them to the weapon shaft spacers.
Stymied by the featherweight we decided to turn our attention to the other 'bot needng work, our 30lb Sportsman. Here we have the eight saw blades for it. We'd budgeted 4 pounds for them, and they're actually less than one and a quarter pounds, so there's a savings right off the 'bat.
Although we made a good start on the chassis a while back, there's plenty of parts left to be fabricated, and by fabricated we mean drilled and tapped, so it's time to break out the drill bits and take a swing at these weapon shaft mounts.
We were much more accurate in our drilling this time out, and soon it was time to dig out the 1/4"-20 tap and cut some threads.
It took a while, but eventually we had one side done, but as you can see here there's a hair of misalignment in the bushings, so we're going to enlarge the bolt holes a little and see if we can wiggle things into orientation.
We got part-way through the other side, when the cold was a bit much, and it was time to break for dinner. Tomorrow we're going to finish the weapon mounts, and install the drive train. Hopefully on Monday we'll have our weapon motors for the featherweight done, and we can finish installing the internal components.
Tags: build, featherweight, ff2, pal30, sportsman
This time in two weeks we'll be on the road to Nashville, on the way to Motorama 2012! Which is exciting, but we still have work to do - the plan is to finish the fairyweight and a beetleweight by the weekend, and then spend the weekend working on the two biggest
'bots. In order to manage that we need to fabricate some parts, and put a call in to Chris over at Speedster Hobbies to see whether we could get some shop time, and Chris graciously agreed. We jumped in the BotMobile with some materials and headed his way. Hit Back after viewing an image.
Chris reminded us of how the bandsaw worked, and we started out by chopping up some aluminium and steel. Boy, we wish we had one of these in the Build Space! Nifty!
Here's what we cut up - DeWalt drive axles, a weapon transmission shaft, two pairs of blade shafts (steel and aluminium), wheel hubs, and trimmed down the blade shaft and retainer for the 30lb'er.
After a spell on the lathe, we had the aluminium round turned down to fit the Colson wheels. Not perfect to the thousandth of an inch, but well within typical Team Radicus tolerances :-)
Chris has a new lathe, and it was working just fine! In fact, he hadn't had time himself to use it yet, so we were the first to fire it up, and it was fun!
After hitting the hubs with a countersink (to start the hole), and a couple of drill bits, we had the hubs ready for the shafts. We hope we have a 1/8" broach back at the Build Space ...
The last lathe operation for the day is to bore the bevel gear for the 30lb'er to half an inch - it's metric, and has a 10mm bore at the moment. We didn't realize this was going to be a tough job, but the presence of a keyway messed things up, and we wound up snapping a bit trying to bore this out. We'll have to do a bit of research into a way to accomplish this ...
With profuse thanks to Chris, we jumped back into the BotMobile and headed back to the Build Space, noting along the way that the temperature was over 80°F - eighty degrees in February?! Crazy.
Turning our attention to the smallest 'bot in the fleet, we milled a hole for the weapon motor wires, and drilled mounting holes for the weapon motor in the front of the chassis.
We've also modded the mounting plate a little, and a couple of #2-56 screws and nuts have started the process of mounting the motor to the plate, but we need 3/8" long ones to mount this to the chassis, and we don't have any. Looks like a trip to Grainger is on the cards tomorrow ...
In this photo the motor is actually slightly lower than it will sit on the chassis, but close enough to see that it clears the ground, which is a plus :-)
There's a lot of wiring to be dealt with, so we decided to mill out a bit more of the top part of the chassis - messes up the CamBam+ finish, but at least it we ought to be able to cram everything in now.
We were originally steeling ourselves to have to cut and solder the receiver wires on the speed controllers, but thankfully Kurtis over at FingerTech uses very flexible wire on his TinyESCs, and we were able to stuff the excess into a couple of crannies in the 'bot, and move on.
Next up is mounting the weapon speed controller. We decided to risk the weight and used a small piece of double-sided foam tape to stick it down to the motors at the back of the 'bot, and again we stuffed the receiver lead into space around the battery.
Which brings us to power cables. Because all the wires are quite fine gauge, we decide to just try and solder them all together, and with some electrical tape a zip tie, got them all close enough to hit with the soldering iron in one go. Not pretty, but seems to hold fine.
So we did the same thing with the positive power leads, and did actually remove the zip tie before putting some heatshrink on the end of the leads.
Time for a sanity check. The chassis, plus it's nuts, and a couple of bolts to approximate the missing motor mount nuts and bolts, and we're at 149 grams - looks good to us, but we need to hope that NERC's official scale is close to our's. There is a difference in latitude between Austin, TX, and Harrisburg, PA, but hopefully not enough to cause a couple of grams difference ...
This was a shot after a quick test drive of the 'bot. It is pretty zippy, but fairly easy to control - without the weapon, of course! We'll see tomorrow how it drives with the weapon spinning on the front.
Last shot of the night, and we've milled a small hole on the top of the 'bot to be able to get to the battery connector, so we can disconnect the battery after a match. As long as we can get those #2-56 x 3/8" screws tomorrow this 'bot will be finished tomorrow night!
Tags: build, fairyweight, featherweight, ff2, lathe, pal30, sportsman, tt1
At this point in time (three weeks til Motorama) we have a finished antweight, a finished beetleweight, and two finished hobyweights. Still in progress are a fairyweight, an antweight, two beetleweights, a featherweight, and a sportsman. We changed our mind on the fairyweight design a couple of weeks ago, and we're not feeling entirely confident that the featherweight will survive it's first hit, but nonetheless we're pressing on! Hit Back after viewing an image.
First order of business is breaking out the table saw and cutting chassis parts for the fairyweight and sportsman. We've cut some UHMW frame rails, and polycarb rails and plates - made quite a mess but they're done.
We also have some UHMW blocks for the two halves of the fairyweight chassis, which we'll set Milly on in just a little bit.
We've slotted the chassis parts for the sportsman, and are testing the fit - looks fine so far. We will need to do a fair bit of drilling though ...
... But not so much tapping - Pete Smith gifted us some Nutstrip at the last Motorama, so we've cut some lengths with a jigsaw, and we're planning on using it to assemble the outer chassis of the sportsman, as UHMW doesn't hold a thread well.
Ta-daa! Kudos to Pete for a handy product - assembling this chassis took about an hour, including the cutting and drilling. Much better than having to tap 36 holes!
Meanwhile Milly is off and running on the fairyweight chassis blocks, using the G-code we got from CamBam+ a while back. Should be interesting to see how it comes out ...
... Quite nicely actually! We need to clean up a little bit with a craft knife, but it's pretty much just as we imagined.
Unlike these frame rails for the sportsman! Geez ... out of six holes, one is in the right spot - the rest ended up all over the place! Not good ... for some reason we had problems seeing the punch marks on the drill press. We're going to have to try that again.
On the other hand, Milly is doing fine cutting the fairyweight chassis down to size. A quick clean-up, flip, and she can do the other side too.
To give us this! They currently weigh 70 grams, but are still half an inch too long, and have another bit of pocketing to go, but they do look how we envisioned the chassis to come together.
Lauren's getting in on the action too, working on her antweight Malicious Mule. She's working on the drive train at the moment, and Toni's letting her do 95% of the work, to get the full building experience :-)
The 'bot is coming together quite nicely, although perhaps not as quickly as Lauren would like, but it'll be up and running, and sparring with Poor Punctuation 2.0 by next weekend.
The final shot of the evening is a close-up of the fairyweight internals - there's an awful lot of wire that's going to need to be trimmed down, but otherwise things are looking good. Next step with this 'bot will be mounting the drive motors and wheels, and drilling holes to bolt the chassis halves together. But for now it's time to go grill some steaks!
Tags: antweight, sportsman, build, mill, fairyweight, pal30, tt1, mm
This site contains records of our trials and tribulations in building combat robots. So much to learn, and so little time!