Roc_Xel

Hey ! So in my quest to collecting all Technic 1000+ bricks I'm slowly but surely reaching my goal and I'm looking to buy second hand models to build some of the b-models. Not speaking about MOC's here which I'm very much interested into as well, but these are easier to find out thanks to rebrickable. However, I was not able to find anywhere a list of "official" b-models, not on brickset, bricklink, rebrickable, nowhere really. A few easily come to mind, especially in older sets. My fav set ever is the space shuttle 8480 so this one is an easy pick with the submarine alternate build. Got another set so will do soon. Did both 8868 and was in love with a-model but slightly let down by b-model. Which models should I look at ? Old models included but original set has to be over 1000 bricks. Few models that I've noticed thus far: 8421 (mobile crane) is one of my fav set ever (and probably one of the most underrated sets) and I got both the a and b models built. 8880, original super car, F1 seems pretty damn cool and would probably look more than decent next to current models; The B-model that seems almost better than original is the one of the wood truck (9397); 42009 is imo a very mythical set, and b-model does not really appear to be quite as good, but interested to know by ppl who built it; 42055 (wheel excavator) b-model seems really cool. Any thoughts ? That's the ones that seem of interest thus far, but I'm convinced there's way more, please let me know.

Thanks guys for the answers. Switches are glued indeed and working well and as for the motor both directions gave nothing. Dismantled again and one of the 8cm hose had a small hole into it, and that was it. It now works but honestly I really dont like how the arm works and is positioned (just the grabbing part, not the black part lifting the arm). The cylinder moves freely and sometimes parts disassemble. You also have to lock it in a very specific position to make sure it closes enough and does not open too wide. Everything works perfectly but I feel like the arm part is really fragile in how it works. Anyway, lovely set but comes really short compared to a-model. Then again, a-model is imo in the top 5 Technic sets ever released, if not top 3. Thanks again for helping me fixing it and all the suggestions.

Thanks mate for your help. Yeah the "test" pump is working perfectly, gives lots of air to any connected tube. Clearly will have to dismantle and test every part with this big manual pump to see where the fault lies. When I saw that the second tiny pump connected to the motor seemed much better with the one taken from A model I thought that was it while rebuilding but clearly its not. Shame coz I looked carefuly at each cable when rebuilding the 2nd time and cant find one faulty (my kitten loves biting those when I build, I had to replace two of them that were broken due to bites, hence checked even more carefully ^^). Will check the valves (but got 4 overall with 8868 and using only two for B model, and the other two I have available and unused work perfectly, still a possibility though) and those t shape connectors. Will let you know, thanks again

So rebuilt with the other tiny pump from A model (the one connected directly to the motor in B - model) and it seems to be triggering better, i see more movement so this pump is probably better, but it still does not work. Connected to a regular manual big size pump, and same, it does not do so there's a hole somewhere. Can these T shape connectors be faulty ? Damn I'm so annoyed, first time in my life I don't have a working Technic set, and I can't leave it like that, all functions have to work this is basic rule of thumb. Any advice on how to determine which piece is faulty ? Will have to dismantle a 4th time in any case, this is so damn annoying.

Thanks Milan, was wondering the same but the air these tiny pumps send is so light that it's tough to really say if they work when dismantled. Just grabbed my a model and will switch them to see if they work. If the one on my b model makes the A model work then i guess this was not it. Will keep you posted. Edit : So started putting the A model tiny pump into the B-model, and indeed it seems to be making the motor work a bit more, rest is now disconnected obviously so can't saay it works for sure but looks like it's better already. Will rebuild with this one and see then.

Hey, So I love 8868 so much that I got me another one to build the B-model and have them both. Build is pretty straightforward, but once done when I activate the motor it works well but nothing happens. Clearly the fist grey cable connected to the tiny pump connected to the motor seems to be given air but then somehow it does stop somewhere. Dismantled the whole thing, found out that one tube had broken on one of the valves, and rebuilt it entirely changing the damaged tube with a new one, have tons in stock. Yet, exact same. I made a 20 sec video for you to see the problem, clearly first cable coming from the tiny pump seems activated but then nothing. All cables are connected where they should be, all "holes" are filled as it should, so there's not a cable not installed properly. A mistake is not impossible but I'm on my 50th set and built it twice now so not sure it's that. Was thinking more like faulty pieces but all cables really seem fine from what I see (and I checked them when rebuilding). Is it possible the tiny pump does not give enough air ? Also, put a bit of water on the valves when cleaning the bricks before building but there's no electronic involved and they seem to work absolutely fine. All 3 bigger pumps can be easily extended as well when the motor is off. Please help before I dismantle a 3rd time, I'm sur one you pneumatics experts will have an idea. Thanks guys.