Klirre

Are you sure it's just a regular O-ring? Because I've got loads of them at home in different sizes. The problem of opening the cylinders without ruining them still remains, they're really well built.

A bit off topic but, There are already bulletproof CVT:s on the market, the big issue is not regarding reliability but efficiency. Just look at modern tractors, almost all of them use some kind of CVT. The simplest one I know of is the one made by AGCO (used in Fendt and Massey Ferguson tractors). It only consists of a hydraulic pump and a hydraulic motor both connected to a planetary gear set. Here's a video explaining it all, although a bit simplified The reason they work here, I think, is that a tractor consumes quite a lot of fuel under load and if you're able to stay in the sweet spot of the fuel consumption map regardless of the ground speed you will increase the overall efficiency despite increasing the losses in the transmission. The thing is that these transmissions only work for lower speeds, to get a transmission that works for speeds from 0-200 km/h you would need a different solution not using hydraulics. A car, unlike a truck or tractor, only uses a very small part of its power when running constant speed, even in high (legal) speeds. No matter what you do there's no point in the fuel consumption map of a combustion engine at low load that gives you a low fuel consumption per horsepower made. AFAIK, subaru are playing around with a belt-driven CVT combined with a petrol engine and there might well be some other company doing this. On the other hand, if we're talking electric motors there's the well hated (at least by petrolheads) Toyota Prius which uses a gearbox similar to the Fendt Vario. They have just switched out the hydraulic pump and motor with electric motors connected to the battery pack. Now you can use the CVT in smart ways to either transfer power to the wheels or starting the combustion engine to charge the batteries. If you want to discuss this topic further I suggest we start another topic. I might also have some inputs on hydrogen and fuel cells, moslty why they might not be "the furure".

So... I took a good look on my old pneumatic cylinders from the late 90's. They are in dire need of some lubrication, I will buy some silicone oil next time I'm in a hardware store. The biggest issue is that they're only single-acting nowadays, i.e. they extend but refuse to retract no matter how much I pump up the pressure tank. I suppose the top seal between the housing and piston is leaking pretty badly. Is there any way of fixing this? I tried opening one of them but I'm afraid of breaking them. Do i have to take them apart in order to lubricate them? Otherwise I'll try with silicone oil first and see if it helps at all. Is there any point in polishing the pistons with steel wool or does it only make things worse? Let's assume the worst, if they're shot and there's no way or fixing them, How hard is it to get hold on good large v1 cylinders? I'd prefer the old square bottom ones to match the ones I've already got. I'm thankful for all types of input, I hope there's some pneumatic guru out there who knows how to save my cylinders.

Done, it's available in the first post. I hope that it's not against the rules of the contest to share your LDD-model.

Thank you all for the kind words, it sure motivates me to continue the project :) The first thing I would need to order is some pneumatic hose and try to fix my old corroded cylinders. I really want to be able to show off the trailer in combination with my 8459 loader. Zux: It might well have been my own fault, trying to make a good forum post at 01:00 local time is not one of my brightest ideas :P. I will edit out the comment tonight when I'm home at my comp.

Hi! This is my first topic on the forum, I would probably not have posted at all if it weren't for the pneumatic contest. A combination of me seeing the 42053 EW160 and finding my old lego technic from late 90's and early 00's led me to this forum filled with nice people playing with arguably the most versatile toy ever. I'm a trained mechanical engineer, though not practicing my trade yet, and looking back I believe Lego Technic was one of the big inspirations that made me choose that career path. Back in the day I had (and still have) a 8459 pneumatic wheel loader, and now I was leaning towards buying the 42053 EW160. But why not test my skills (and luck?) by making a nice little MOC for the contest. Enough drivel about the good old days, over to what I've come up with so far. Please bear with me, I am aware that you guys are way better at this, have more parts at home etc. The point of this project was to make something that I actually wanted for my already existing sets without costing a fortune for me to buy and build. It's a trailer suitable for both the 8459 and 42053, inspired by the Swedish-made trailers from Metsjö. I wanted it to be more than just a regular trailer with tipping function, so I'm aiming for a two-step high tip function which raises the rear of the bed before tipping it. The tailgate is automatically opening and closing with the tipping, thanks to a lever on each side which are connected to the frame. The final "function", so far, is a parking support in the front. This is what I've come up with so far, I must say that LDD is really bad when you want to try the functionality of your model. I still haven't figured out how to make the pneumatic circuit work as intended. The goal is to put the main switch on the Digger/Loader/Tractor pulling the trailer, leaving the two-step function automated and built into the trailer. So when you pull the lever to tip your load, it first lifts the rear, then tips. I'm hoping that my old friends, the laws of physics, will solve this for me without the need of two extra switches on board to route the air, but I suspect that Murphy's law will decide my fate in the end. So what do you guys think? Too simple and easy? Too predictable? Put on a LA and paint it gray and you'll end up with half an Arocs? Awesome? Improvements? Other ideas? If the feedback is good enough I'll just have to convince my bank account that I need to make an "investment" or two on bricklink to build it IRL. There's still a lot of things that needs testing which is not possible in LDD, so I'm a bit scared that I will have bought a bunch of bricks that won't work... metsjo-trailer.lxf

Thanks Jim! Another question: How strong are the small pneumatic cylinders? I really need the shorter stroke of the small one. If I combine two small ones, in parallel, how do they perform vs. a large one?

Hello everyone on Eurobricks! I've recently found my way back to Lego, after stumbling on my old Technic sets :) My absolute favourite was the pneumatic front-end loader, I had the first version from '97. If it only was sold in 1997 I must've been 6 years old when I got it, good times. I've been lurking a couple of weeks while playing around with LDD then this awesome contest showed up, and I felt that I must try and contribute even though I'm a bit rusty. The biggest difference is that I've only used "studded" technic, not the newer beams which to me seem superior in every way. It always annoyed me when the studs get in the way of moving parts. I was planning on buying the volvo ew160, but now I'll wait and see if I can win it. I don't see any point of owning two of the same set when you can buy separates on bricklink. Now for my post here, I have some questions: My old pneumatics are corroded on the pistons, they work but they're not running very smooothly. Is there any way of fixing this? I've found the guy who sells pneumatic tubing, http://www.blokbricks.com/, so that part is easy to source. But dhc6twinotter wrote about getting the pneumatic bag for 42043 as the cheapest source of pneumatics, where do I find this? The parts on bricklink are pretty expensive as earlier mentioned. Final question: How worn are the "used" things on bricklink? Most of my old lego is well used, I built more than I played with the models. Especially pneumatic cylinders, will they be in good condition if they're marked "used"? How about PF-battery boxes and motors? Was planning on buying the 8293 set for my future EW160, but maybe getting a batterybox + m-motor is cheaper and better? I don't care much for lights anyway, the switch might be useful though. Lots of things to ask in this thread, but hopefully most of it is relevant for the topic. I will probably post a discussion topic for feedback on my MOC in the future, I need to tinker a bit more in LDD first and fix my old pneumatic parts. I really want to build that old wheel loader again, it's been 12+years since last time...