DrJB

Eurobricks Dukes
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Posts posted by DrJB


  1. 1 hour ago, XenoRad said:

    Actually, taking a look here - https://brickset.com/sets/containing-part-6276974 shows that that part appears in plenty of current sets in yellow. But seeing how in that 42121 set we already had 4 in LBG it was likely cheaper to add one more in the same color rather than add a new color. Also, there's the B model where parts would be arranged differently so that could also have something to do with it. But with an uneven number of that part I'm sure they could have had one a different color and not look bad.

    EDIT: Ah, beaten to that reply.

    Not so sure about that anymore (assuming I understood your point correctly). In the past, they had to pre-mix specific batches of plastic to make specific colors. And that is why on older sets all the axles are either black or gray. I believe I've read somewhere that they changed their injection machines to 'on-the-spot-color-at-will' technology and now, it's 'cheaper' to build any part in any color. The first 'explosion' of colors in axles came with the Bucket-Wheel-Excavator ... or maybe they put in some incentive (new colors) to increase sales of such set. You still need individual storage and parts management for the individual colors though. In fact, it is such injection machines that are now having a hard time keeping colors consistent ... the smaller the batch, the more difficult it is to keep the color consistent. But, you already knew all of this :)


  2. 1 hour ago, gyenesvi said:

    Since we are talking about possbile new parts, I think nobody mentioned one seemingly obvious novelty: the recent buggy had a new 15L beam with perpendicular axle holes, which seems something that should be abundant intechnic as it would simplify many builds. I’d expect these new large models to introduce more of that in various lengths and colors, it seems like an obvious direction of evolution. What do you think about that?

    You're absolutely right. I saw that part a while back on a Chinese copykat and thought TLG will never make it as the mold is a bit more complex than the straight lift-arm (due to perpendicular holes). Glad to have more options available to us. 


  3. On 2/15/2021 at 12:30 PM, NKubate said:

     ... Which is why I am hardly active here. I got so many times either flamed for my posts or completely ignored that I can't be bothered anymore. Sure it is in people their nature to complain, but in particularly arguments seem to escalate on the Internet where everything becomes polarized. Instead of posting on forums open to everyone I prefer just to write my point of view through blogs and leave it at that. If people really want to discuss things they are always welcome to contact me and I will gladly continue discussing things behind the scenes. I'm really not that hard to find or reach, it just requires a little extra effort. But we're getting way off-topic now...

    Yes, I know the feeling ... that is why I'm no longer a regular... I disappear for weeks at a time then an old flame comes back to life. Good 'hearing' from you again ... or maybe we're getting older (and wiser) and have less and less patience for non-sensical squirmiches. 

     

    Also ...

    Not sure about the community at large ... but I find it 'impressive' (or is it disheartening) that a thread with so many answers ... does not have a single photo !!!

    I'm disappointed though, as when I come here, is to see pictures ... not read incessant rambling... To each his own I guess.

    *Peace*


  4. 9 hours ago, kristl said:

    I think designers should focus on the blade and makesure it has the freedom of momevement of the real machine. With that what I mean is it should have blade elevation control, tilt, rotation and not just simplified up and down elevation and also the same for the ripper or maybe alternative rear attachment such as grapple for instance.

    Rezultat iskanja slik za dozer rear attachments

    Yes, you're absolutely correct.  On the larger dozers, the blade typically has at least 3 degrees-of-freedom: up-down (connected to the track frames), pitch, and yaw. Would for sure love to see that replicated someday.

    42 minutes ago, Milan said:

    (Thanks for a great post explaining it)
    Apart from Jorgeopesi's models, another example of the articulated tracks from a Liebherr Loader, with a cross-beam attached to the chassis in the middle, with cylindrical joints to the left and right track frames:

    16350346137_d13fe903d3_c.jpg

    Beautiful! Thank you for sharing. You can tell for sure (between the spring-loaded sprockets and equalizer bar) that the designer has spent a lot of time researching dozer kinematics. Are the instructions available? Never mind it, found its own thread.

    2 hours ago, Xan326 said:

    ...  Look back at x928cx1 for an example of why limited scope pieces fail when they don't have a high volume of usability ...

    Is that x928cx1 one of your favorite parts? .... Mine too ... together with other parts waiting to be used someday ... :) 

    If I recall, those spring loaded axle connectors x928cx1 were used primarily with Hockey players. Not sure they were introduced within the Technic theme ... but then again, I could go and check BL quickly to confirm.

    The black parts in the top middle, seem to be the earlier version of suspension springs for system (not technic) .... they do have a very short travel though.

    Favorite_Parts

     


  5. Sorry about changing/editing my post ... I sometimes post a reply, get distracted (by work) and then come back ... If I may, I think you should 'uncross' the text in your. It is very useful information that you are providing and would make it easier to read. My collecting since 2003 comment was about my 'second' awakening. I first experienced Lego Technic with 851, when it first came out in the 80's ... I think.

    Glad we reached consensus. Cheers.


  6. I have to admit I have little patience with long posts... though sometimes I write paragraphs myself.

    Yes, I did read your post more carefully this time, but there are 2 points:

    1. My first wave of comments was about 'wishes' or hopes/dreams ... it was not about what I think TLG will do.

    2. Your logic/math about ROI and why it does not make sense for TLG to invest in specific parts is a bit 'out-of-touch' with reality, at least if one looks at all the new flagship sets in recent years.

    TLG has on many occasions issued specific parts that they used only ONCE in specific sets. Some of those parts were re-usable, other not much so. The portal hubs of the Unimog had very limited reusability. Many of the Bionicle parts (which some view as an extension of Technic) had zero re-usability. There is another popular thread (Lego for Kids and Reusability) where the consensus is that nowadays, TLG is after 'build it once and display it'. If you believe that, then who cares about reusability? Do you think the many new panels/fairings (and color) of the Sian are reusable? Not for me ... but then again, I'm not a MOCer and cars do not appeal much to me. 

    Yes, you have your own expectations (with longer LA's and a custom blade) and own version of reality and 'eco-system'. All of that is defendable/respectable, and that is what diversity is all about. Let's just be patient and hope that TLG will deliver on BOTH of our expectations ... whether they make ROI sense or not .... In the end, relax my friend, this is just a hobby, and you're free to dream/speculate and build whatever comes to your imagination. ;)

    *peace*

    On 2/14/2021 at 12:21 AM, jorgeopesi said:

    That is why I love machinery because is more than you can see at first sight, my old caterpillar d11 and komatsu d575 used that configuration.

    I browsed some of the builds on your brickshelf account. Those MOCs are truly fascinating. If I may though, would be nice to link some pictures as those would 'entice' more people to go and visit.

    Thank you for sharing. :)


  7. 8 hours ago, AI toothbrush said:

    No you cant connect them like that. The PF extension cables have the underside of a 9v system connector.

    When a person answers to my comments with a 'No' ... that says there are two possibilities: either they have no clue about what I'm talking about ... or, I've lost touch and am not aware of the latest. If I recall, the original question was what happens when battery boxes are connected in either series of parallel. I do not recall the question mentioning WHICH specific battery boxes. Yes you can stack PF cables, and yes you can stack 9V cables. Now, based on the cables YOU have, can you connect batteries in parallel? I do not know. I have many different cables (I've been collecting Lego since 2003) and also many different boxes (such as shown below). Incidentally the small 9V box is my favorite. For sure, you can connect the boxes below in parallel with a 9V cable, then use the PF extension cable to go from either battery to the PF motor of your choice. If you're thinking ONLY PF cables, then you're correct. You also might be a newcomer to Lego (less than 17 years) and the pictures below would look like ancient artifacts to you :)

    4760c01.original.png  5115-1.png

     

    Since we're on the topic, I also have the following boxes, and some of them interface to a computer (with an old DB9 Serial connector). I love those boxes and the old 9V cables. To change polarity, all you need is rotate the connector by 90 degrees. Back then, one needed to understand a bit about electricity ... and now TLG has made everything 'idiot-proof' ... whether it is the PF connectors, or the reversible gear clutch.

     

    2954.png4115.original.png?0

     

    6 hours ago, Toastie said:

    Which changes quite a bit with load on a motor of course. A stalled PF XL motor draws 1.8A (https://www.philohome.com/motors/motorcomp.htm) whereas with no load it draws 80mA at 220 rpm. No surprise here, this is what happens to E and B fields when you don't let them do what they want.

    And yes, when there is over-current protection in the battery box, nothing much will happen, as this one will kick in as soon as TLGs decision, what over-current means, is reached.

    Now, as we are reading here about 9V - PF conversion cables, custom wiring, etc., all of which I have done extensively (30 PF/Technic motor driven switch points wired up with LEGO wires = dramatically negative budget, which the higher authorities in this household never pass! So: Go cheap = DIY). The old battery boxes don't have any electronics in them. And then lets say we start out with fresh alkaline batteries. When you put these in parallel, V = const = 9 V (ideally of course), but A(max) = 2x. At least this is what I have learned back in the days, and here it is from a vendor (which does not mean at all it is correct, of course!): https://www.digikey.de/en/blog/series-and-parallel-battery-circuits.

    Going back to the alkaline batteries: They can easily provide 1A (not for a long time :-) and with only 1V https://rightbattery.com/118-1-5v-aa-duracell-alkaline-battery-tests/ ) so a stalled PF XL motor hooked up to unprotected 2x9V battery boxes in parallel may well produce 2x6Vx2A = >20W in heat. That of course will not happen, as at every electrical connection, which has only a slightly elevated resistance, the plastic material around it may have hot times.

    And yes, when the charge state of the batteries is different, the first deal which each other quite a bit and when peace has been announced, the leftover is available for fun.

    As least this is what I make of it - but you know what? I just work here :pir-laugh::pir-huzzah2:

    Best
    Thorsten 

     

    Thank you Thorsen, very useful information that you have provided. In the past, it was relatively 'easy' to discuss these topics but now, with 'smart' battery boxes and custom electronics/protection circuits ... the simple physics are often not sufficient... unless one has spent a great deal studying them (like you have). Cheers. 


  8. 17 hours ago, Xan326 said:

    What's the actual likelihood of us getting planetary final drives? ...

    Fascinating, isn't it?

    Here we are talking about desired features (wishes) and realism ... and you come with your visionary comments and negate all of It? 

    Bravo, if you knew enough about Technic as the many on here, you'd have noticed the past several flagships, starting with 8448 all had new/specialized parts. It's Ok for us to dream, and it's Ok for you as well to spend $450 on a big box of common parts. Heck, enjoy your hobby.


  9. 1 hour ago, Toastie said:

    This depends. In principle, you are absolutely right. Things may change though when it comes to increasing load. A stalled XL PF motor draws serious amperage when the source allows that. So without a PF receiver in between, current may reach unhealthy numbers. With receiver that one will max out, as they are overload protected.

    So in the end, with two batteries in parallel, one receiver controlling power (and this limiting current), it is as you said: Doubling the run time.

    Best
    Thorsten 

    Of course I'm right ;) ...

    The current is NOT decided by the power supply. The power supply provides the voltage, and the load decides how much current it needs, based on its own internal impedance (Current = Voltage / Impedance).

    So, assuming the two batteries are 'equally' charged, my explanation above holds. If the two batteries are NOT equally charged, then there could be current flow between the two batteries. I say 'could' because it all depends on the electronics in the battery pack.

    19 minutes ago, dr_spock said:

    You might have to make a custom cable or take apart and wire the battery boxes together. The PF extension cables and other components don't seem to permit connecting more than one power source.

    I haven't played with PF cables in a while, but if I recall, you connect one cable to the first battery, the other to the motor, and the second cable to the second battery, and again to the motor. If I recall, the PF connectors can be stacked at will ... just like lego bricks

    There might be other options depending on which cables you have. There is an adapter cable that has a PF connector at one end and a 9V at the other. Though here, I would be careful with polarity, or you could potentially destroy the batteries (they'll overheat first)


  10. Not to change the topic completely, but I had my share of issues with BL as well. I had some old/sealed sets I put for sale, Two buyers from Europe never paid me (and I did not send the sets) ... BL charged me $50 ... I tried to reason with them, but they insisted that the buyers paid me by 'other' means (not paypal) and that I 'violated' them i.e., took advantage of them ... I could not prove my case, and neither could they do theirs ... but the management (pre Lego) was not the best. Here I am ... complaining again. 


  11. Well, based on some of the latest answers ... I'm tempted to say we have more kids on here than adults.

    It is human nature after all, to complain about everything, isn't it ?  Some say we're born with that ...

    ... But it takes a 'grown-up' to see the positive in every situation (set/part) and either focus on that and get their joy, or take a pass and move on to something else.


  12. Double the current and double the voltage is 'nonsense'.

    Connect in Parallel (feasible, with PF+9V cables) - double the play time, voltage is the same, current is the same, batteries last twice as long

    Connect in Series (no feasible with PF) - double the voltage, might fry your components if they have no voltage protection.


  13. This has got to be the busiest thread ever ... my phone keeps on beeping every time there is an update. Either people are very passionate about this topic, or this confinement is making us very 'engaged' hobbyists.

    We've heard many opinions so far, so, what's the final verdict? Have we reached a consensus or is it all over the spectrum? I'd lean towards the latter as we all come here with different interests, expectations, history, time, budget, ... disappointments too.

    It would be interesting to move past the venting/praising and turn this topic into a Poll, with each of the original questions graded from 0 to 10. Maybe then, we can give some feedback to TLG as to how "We, the dedicated/faithful AFOL Community who refuses to buy any copykat from PRC and willing to spend $450 on the CAT dozer, truly feel". Of course we can also add questions like:

    1. Technic is getting expensive

    2. It is the beginning of the end for TLG - or another cycle ?

    3. All of these are perceptions from the older AFOLs ... with the new younger hobbyists, they have nothing to compare to, and thus will be happy whatever you throw at them ...

    Thoughts?


  14. Now I realize what the issue is. I bought my Dirt Crusher used/assembled off eBay. It came with only one shock absorber. However, I just checked the instructions, and there seems to be 2 models (A&B). Apparently, the one I bought off eBay was the B model. The A uses two springs, the B uses only 1. Fair enough, I learned something new today. Was not aware of A vs. B models on the Racers series. Look at page 40, where they remove the rear spring, for the B-model. Here are the building instructions:

    https://www.lego.com/cdn/product-assets/product.bi.core.pdf/4248620.pdf

    DirtCrusher

     

    19 minutes ago, koalayummies said:

    But which set/car are you talking about that might have the incorrect information regarding the spring part then? Lets check it out.

    These databases have been thanklessly compiled and maintained so lets at least verify before dismissing the entirety of the archive as inaccurate or suggesting that those that put in the work are unqualified or colorblind based on one potentially misremembered error.

    I'm not dismissing the entirety of the archive ... all of us have different experiences with the archive. There were times where their inventories did not agree with what I have. If you check the forums within BL, there were many instances where users reported on incorrect listings ... nothing new nor unique here. Are we beating down on BL? ... absolutely not! 


  15. 57 minutes ago, koalayummies said:

    Brickset's inventory also lists 2 and they state that the data is obtained direct from Lego's customer service replacement parts page. "Important note: We do not control this inventory and cannot currently make changes to it. Use it as a guide to the contents of the set, or to find out part numbers when requesting replacements."

    Also I found two listings for sale of this set and it clearly shows 2 of the spring piece in both, one from Nevada and one from Austria. https://www.ebay.com/c/1200724970 https://www.ebay.com/c/149215073

    Good point. I was thinking of a different car (not 8369, but something similar) ... and the inventory sometime back said it had 2, when in fact the one I have has one. Maybe they corrected it after all. In any event, it seems the part I'm after does not exist after all in dark purple ... yet its color looks very close to dark purple ...  This is just some parts fading after years in storage. What I found 'strange' is that all parts that have remained blue are from one mold, and those that faded are from a different mold. I recall reading sometime back that Lego builds parts at various locations ... With the mold information above this suggests that different plants have better color/chemistry control than others.

    7 minutes ago, Alexandrina said:

    Just to add to the chorus, that's not dark purple, not even close. It does look exactly like many blue bricks I have myself from my childhood (so the 2001-2010 period) that have been stored in drawers not exposed to sunlight for much of their lifespan. Blue bricks naturally discolour, and I think that is what you have 

    The more the merrier  :)


  16. Thank you @Murdoch17. I've seen sun-faded bricks, and the fading is usually not uniform (especially visible in white bricks as some sides are yellowish, others white). How do you explain that the colors are uniform? Plus, the parts have not been exposed to sun at all. They were in storage in a closet in plastic containers. Also, the true blue parts have all the same mold, whereas the 'purple' parts have different mold markings. Could TLG have sourced parts from 2 different plants/locations, and one of them had non-stable color chemistry ?

    I said dark purple because the color matches those bionicle parts ... my own color expert (my daughter) says it is Dark Purple  :)

    So the issue then is ... unstable chemistry formulation that leads to discoloration? If so, is there a way to recover the original color? 


  17. 9 hours ago, Jurss said:

    CAT has those drive gears on the "top" middle. So, I supose, it has something different. Articulation then should be around those points, it they are there.

    Correct. There are many reasons why the CAT has 1 sprocket and 2 free idlers. One of such reasons is better durability. Also, that concept is found primarily on large machines. On small machines the configuration is 1 sprocket and 1 idler only (as in the picture I posted). For sure though, the left and right track frames are articulated though a bit different from what I showed. 

    One of the consequences of such elevated final drive design is, because the tracks wrap around the sprocket over a smaller angle, the teeth on the sprocket must be much stronger, to deliver the needed/high tractive forces against the ground. One more detail. the CAT machine most likely has a fully mechanical transmission i.e., the power is transferred from the engine to the final drives via gears, and there is a mechanical differential between the left and right tracks. On smaller machines, the transmission is typically hydro-static i.e., the left and right tracks are fed by a combination of hydraulic pump+motor, both with variable displacements. In such case, the differential is purely hydraulic. There are pros/cons for each design and some machines use fancy closed/loop controls to assist in straight line-driving and steering. Those machines use very fancy mechatronic solutions and we have software engineers working full-time on optimizing their performances. In your typical car, it's very easy to travel in a straight line. In a hydro-static transmission, and uneven ground (one side of the machine traveling on mud, the other on gravel), one needs very fancy control algorithms.

    The recoil springs serve multiple purposes. For example: if a hard rock gets trapped between the track and the sprocket, the springs offers some 'flexibility' so the system does not self-destruct, as it enables the track to 'jump' teeth. I have to call a colleague of mine to remind me of the other functions of such spring. Needless to say, there is a lot of engineering and safety features built-in such machinery.