Moz

For my current project it's be handy to have a motor attached to a linear actuator but next to it rather than hanging off the end. I'm trying to get two LA's operating in close proximity with only a fairly compact and highly loaded pivot axle to work with. The LA on the moving side of the joint is not heavily loaded but it would be nice if it moved fairly slowly so gearing down a bit would be nice, but extreme strength isn't required. Making it narrow would be good - it's for the powered tailgate of a dump truck so it gets attached to the side of the dump bin. My first attempt is 3 studs wide (same as the M motor) and same length as the LA. It looks like this: I'd really like feedback and further suggestions. It would be ok another stud wide, but not more, and lower gearing would be nice - the 8/24 gears will work but ideally lower than that if it doesn't make the thing too large. And stronger also - currently if I let the motor run at the end of the LA travel it quickly falls apart. Adding the two extra 3 axles in the 5 long half width liftarms doesn't change that. Thanks moz (more photos including parts photo)

I'm very curious about controlling that steering style - it's something I've struggled with in a larger scale model (14 studs wide) and still don't have a good solution for. To get a slightly tighter lock I'm using 3 stud at the wheel, 4 on the chassis, and pushing on the middle of the rear link arms, but there's a lot of slop making it tricky to get a good centre position or even full lock. I've been playing with small LA's but that really makes the steering huge. But it is very cool - that design makes it possible to get steered wheels into not much more space than the arch that would enclose them straight ahead, so it makes for a much more realistic model.

Do you mean longer than the old single-acting ones, or just that long and double acting? Mind you, those were a little hard to find 10 years ago so I suspect they're almost imaginary now. They were also a little flimsy IIRC, you couldn't get as much force out of them without risking the pushrod bending. I wonder if that is why we haven't seen a replacement for them? If we did, and they were double acting, I think it'd be really handy if both pneumatic connectors were at the base. It'd make the mold a little more complex but the cylinders somewhat easier to build with IMO.

This week I've done a quick powered truck to pull a bunch of trailers built by kids. It's pretty basic but doesn't look too bad I think. The kids will be getting a kit of parts for their trailers, and I tried to mostly use those parts for the truck as well. It may not look like it, because the skin is mostly 1x5x6 panels and 6x10 plates that aren't in the kit, and I had to add motors too. But the wheels, steering, chassis are from the kit. Hence the dodgy doors, the SNOT parts in the kit are a bit limited. Pics here: http://www.moz.net.nz/lego/roadtrain/index.php

I bought two, mostly so I have a few more copies of the new bits to play with and because I got them at a reasonable price. I'm tempted to onsell another one because now that I have them I'm not as excited as I was (I actually bought four and onsold two, because Australia is a long way from places you can buy Unimogs and that made the postage per unit lower). What I am sad about is that someone on Bricklink was selling Unimog wheels cheaply and I didn't get my order in before they upped their price.

That's great. Did you start with the idea of a music box or the Jaquard loom? Either would be cool. Of course, even cooler would have been just gearing things directly so it worked, but that would be in the "unfathomably cool work of genius" category (ie, I don't think it's possible)

Isn't that wee gap down the side going to bug you? I assume from that that you're modifying shelves rather than building from scratch?

One should be ample. I regularly use 7.4 or 11V (2S or 3S) packs that will deliver 100A or more for other purposes. A small (2AH) pack that's rated to 20C or more is only about $30 and will deliver 40A (obviously, for 1/20 hours = 3 minutes). Depending on your design it may make more sense to use two or three 5AH batteries in different places around the model. The RC helicopter people use these batteries for their enormous power to weight ratio. The other option would be a "12V" LiIon battery drill, which will be 3S/11V, and will have better battery life if you buy a half-decent one (500 cycles to 50% capacity rather than 200), and you get a free drill with every purchase :) The real advantage of drill batteries is that you get two batteries and a charger for a reasonable price, and if you don't wreck the contacts they will still power the drill. 11V is possibly a bit on the high side for the IR receiver but I don't know that for sure - I'm sure someone on the forums has played with that.

It's in my online dating profile, and my google+ profile, and there's another AFOL at work that I chat with so half my workplace know. I enjoy saying "Lego's great, it's so cheap compared to playing in my workshop". Which is true, I made a four poster bed recently, about $600 for two weekends entertainment. Admittedly, now we have a four poster bed, but building that stuff wears off really fast for the people who have to live in a house crammed with cool projects. Lego at least I can take apart and build something else with.

I'm not saying red is especially expensive, just that the parts cost really mounts up whatever colour you end up using. $1500 for one of these is probably more realistic than $1500 for a train. One problem with the train is that you might exhaust bricklink and then it gets expensive for the parts that you can only get in sets. Those 5x11 panels are annoying to buy, although if you can live with white and green the Desert of Destruction set is being remaindered now (http://www.bricklink.com/catalogItemIn.asp?P=64782&in=S). And so on...

I make the bed 7 panels long, 6 wide = 77 studs. Based on my current PF road train project I think $1500 per unit is optimistic. Costs add up when you start counting parts by the hundred (or by the kilogram). Those 5x11 panels are ~$2 each and there's 42 of them in the bed (brick takeover has 148 @ $2.50). Add 10 XL motors to drive the wheels, 8 M motors for steering (plus 10 turntables) and a few IR receivers with battery packs and you're over $500 before you start on the structure. Lifting that bed will take an array of linear actuators or pneumatics, and you're going to use a lot of tubing in your pneumatic suspension too. From Australia I've been budgetting about $150-$200/kg excluding PF because I end up buying some parts at ridiculous prices. Or buying a whole set and using 3/4 of it because that's cheaper. Redesigning models to use cheaper parts or cheaper colours becomes well worth the effort. Building that bed out of 1x5x6 panels instead of Technic panels, for example, drops the cost by about half (two 1x5x6 panels are ~60c and are a little bigger than one 5x11 panel at $2), and they're lighter and flatter to boot. But getting those panels into an angled structure is not easy. Still easier than finding the (77 x 2) red #5 join parts you need for the existing bed, I suspect. Unless they're available from PaB.

I find that I can get reasonable strength/weight ratios with studless, but they seem to be stronger in tension than compression unless they're quite solidly braced. Not great for your stuff, but for the truck chassis I'm working on at the moment this setup works well and looks quite good (IMO): The 2x3 plate is quite solid but tends to work loose if there's much flexing. That's annoying in the middle of a model, and they're somewhat tricky to lock in place. The multipart pinned brace is expensive and heavy, but self-locating. If you're really keen using a 4 axle instead of the 2 axle and putting a perpendicular joiner on each end stops it rotating and means you can just stack 15 long liftarms end to end. If you do that you only need one bracing part (with 3 long pin friction) in the middle of each group of 4 beams. Building with these really has to happen in CAD - because of the open 3 holes then 4 holes pattern with 15 liftarms too often I end up needing to put an axle somewhere that's blocked, and rearranging them is a pain if you can't just select one whole side and drag it two holes along, or simply delete the pin friction and replace it with an axle.

To many builders it seems pointless to pay the Lego premium if you're just going to assemble a plastic kit according to the instructions and leave it that way. Much cheaper to go to a model shop and you get a much more realistic model to boot. Lego only really makes sense if you're going to actually play with it. I realise that there are a lot of people not like that, just thought it was worth putting the other perspective. But me? I buy for the parts. Mostly studless these days, but I used to build studded back in the day. FWIW, CAD helps the transition and makes designing the tricky bits easier. It's much faster to grab an assembly and move it one hole along than take a whole model apart and do the same.

Finally got round to writing up a bit about my storage setup. I build with Technic so there's a lot of small compartments and rather a large number of different parts that I use often, as well as the hundreds of small connectors in each model. I built my own containers out of plywood so I can get exactly what I want, but I also have a numnber of plastic compartmented trays stacked next to my desk. The wooden trays are 600x400mm and 50mm or 80mm deep. I have a towel over the open part of the desk which is really handy for Technic builds because there are so many small parts that roll easily. The towel stops that, and also helps with bouncing. So, my desk: Technically it all packs away, but in practice I rarely get around to doing that. More details at http://moz.net.nz/lego/storage.php

While I'm making a bigger MOC I have a mental list of parts that I need (usually in a particular colour - MOC prototypes tend to be multicoloured so the structure is there but the colour is wrong), but really must move to keeping that list one the computer because I sometimes over-buy if I make a second order before the first one arrives. I mostly do this with bigger or more specialised parts, and just add small/cheap/common parts based on what I see browsing through. This can mean ordering $100 worth of "what I need" plus $300 worth of "that might be useful". I have two main strategies: - buy a specific set or two, then add whatever interesting parts the seller has, and sometimes a small set if it looks useful. This is usually based on a big set being available cheaply somewhere, so I buy 2-4 of them and fill out the order with small stuff. Often I'll be ordering one of those sets for someone else to reduce postage costs. Being in Australia can suck at times - postage is ridiculous from many places. - make a want list and search for the stores with the best combination of availability and price, then make a spreadsheet (with formulas) so I can work out the cheapest way to get everything. I've discovered that it's sometimes cheaper to buy parts I only need a few of at a much higher price because of postage quirks, and it's not always intuitive (paying 25c each instead of 10c for 50 of something because postage is "free" from the more expensive seller, in that it doesn't add to the existing postage cost, even though I'm also ordering from the cheaper seller but the extra would kick the postage up too much).

As is always the way, if you had a bit more money an 8043 excavator is a bargain way to get the PF parts (except the XL motor), and once you subtract the cost of the PF bits the price per piece on the rest is very low. If you sell off the tracks and associated parts the rest are almost free.

I think they are all motorised, the middle set are just not powered up. They talk about swapping wheel groups in and out, so it seems likely to me that there's only one type of wheel group, the powered one. I also read it as having two motors per unit, and the two sets of power cables in the images support that. This quote on the economics page: Note the plural "motors". Of course, in Lego it's hard enough to build a planetary gear system, let alone one with a motor inside it. But this is an intriguing truck to look at. I wonder if it drives the way the 4wd/4ws telehandlers do - those are quite fun to drive, especially offroad. But given the size I suspect it's kinda boring -scaled up vehicles tend to be structurally weak and have low power to weight ratios. Also, the way the tipping bed works looks quite cool. It seems to rotate the whole thing on a turntable, including the tipping mechanism. So it's not a conventional side tip unit, it's a rear tip unit that pivots. I suspect you'll want some supporting wheels under that to make it rotate easily and not break the turntable.

That was kind of cool. I think it'd be easy enough to build some kind of working ship, the obvious one that springs to mind is one of the numerous floating cranes. But a dredge or roll-on roll-off ferry would also work. More complex would be some sort of fishing boat like a trawler or (controversial) whaler. If you wanted to get silly I think a super-yacht offers lots of options - from the various launchers for smaller watercraft and helicopter(s) to "open it up and see the insides" - one that split down the middle so you could see the engine and so on would be cool. If TLG went wild they could possibly make one that floated just by using a pile of one of the tanks they make. Use a series of pneumatic tanks inside the "hull" to make a raft. It wouldn't float very well, but it would float and I suspect could be made to float realistically. But that would probably eliminate motor functions which would be sad.

Did you consider supercar (8880) wheels? I just bought two lots of 4 for $CA25 and Euro15 so they're pretty affordable. Not easy to drive, but they're big. Also, if you trawl some of the older sets for sale on Bricklink it might be cheaper to buy a bunch of the old sets that have 2 or 4 24x43 wheels than to get them separately. But you could just wait for the UniMog to come out later this year since that seems to have big road wheels :)

Rather than start a new thread, I hope it's ok to add to this one. I'm struggling with the same issue - 32019, 32020 in LDD (62.4 x 20 S wheel + tyre) is in LDD and SR3D but I can't find it for LDraw/MLCAD, and I really struggle to use SR3D at all effectively.

OK, I'm new to this forum but I'm in my third bout of Lego/second AFOL, so I've been buying a fair bit. No-one I've bought from has given me a bad experience, in fact I'm pleasantly surprised. Worst experience was not the sellers fault - 44Bricks posted just as the airline bombing furore happened in Europe and DHL decided to send my package by sea (at the air freight price!), but lost track of it so there was a month when they couldn't tell him where it was, the online tracking said it was still in his town, then magically it appeared on my doorstep. The box was battered but his packaging was better than their attempt at crushing :) http://www.bricklink.com/store.asp?p=COINCOINBRICK - 3 second hand sets (5571,8880,8258), he went far above and beyond what I would expect. Both in labelling each bag of parts with which set it was from, good packaging and posting promptly. Then shipping me not just the two parts that were actually missing, but all the "extra" parts that I never expected to have included with second hand sets (the extra pin friction, 1x1 round plate, all that stuff). http://www.bricklink.com/store.asp?p=liesbeth (another vote for her): agreed to debox new sets in exchange for the stickers, halving the postage cost. Posted promptly. http://www.bricklink.com/store.asp?p=PLAYEXPERT Consistently one of the cheapest for new Technic, appears to post things the day they're paid for. Has a lot of stock and reasonable shipping prices, so when you do want four of the Unimog once it's released he's probably the fastest way to get it. Gives a small discount for multiple orders, will not debox (I don't keep boxes so paying for them to be shipped is a bit pointless), but he's still usually cheaper by the time I include shipping to Australia. http://www.bricklink.com/store.asp?p=44bricks has really old Technic and some good parts. Fast to ship, good packing and prices (bought 8275 + 8880).

I would also try running both off one battery just in case one motor runs slower than the other. It would be annoying for that to be the problem.