November 26, 20168 yr Author 28 minutes ago, Kit Fisto said: Take this part (2983 BL): And add this: Insert the stud in the pulley and you have a really great clutch(Original idea by ZED http://www.brickshelf.com/cgi-bin/gallery.cgi?i=3414030) Very cool progress, btw :) That's a nice one indeed! Does require some bracing to avoid the stud from popping out though. I know there are more ideas out there that give more resistance. For instance: And my version is similar to one from Sariel: http://sariel.pl/2009/01/linear-clutch/ Edited November 26, 20168 yr by Didumos69
November 26, 20168 yr Do these custom-built clutches preserve their clutch force over time, or will they have less friction? Is it a reliable construction (repeatability)?
November 27, 20168 yr Author 13 hours ago, Lipko said: Do these custom-built clutches preserve their clutch force over time, or will they have less friction? Is it a reliable construction (repeatability)? If the clutch only slips on very short, rare and infrequent occasions, then yes. I integrated this in the Porsche in june and it preserved its friction over time. But I wouldn't advise using this in a motorized function or in a function that relies primarily on the slipping of the clutch. Edited November 27, 20168 yr by Didumos69
November 27, 20168 yr Looking with a big interest after this topic! Keep doing! Sure you will get nice car at the final point! Edited November 27, 20168 yr by Aleh
November 28, 20168 yr Author 15 hours ago, Aleh said: Looking with a big interest after this topic! Keep doing! Sure you will get nice car at the final point! Great! I'm afraid the bodywork will be a big challenge. Back on topic. I finished the design of the shifting mechanism and the rest of the mid-console. Before I can build and test it I have to wait for some parts that I had to order. Meanwhile I've been playing with the seats. I want to have an idea of how much space they exactly need. So I stumbled upon the idea of making the seats adjustable. It's not a very conventional way and I'm not sure about the ergonomics, but at least the driver can scratch his a-s-s while driving . Â I'm not sure about the final color scheme yet, so for now I made them bluish gray. LXF-file of the seats can be found here. Edited November 28, 20168 yr by Didumos69
November 28, 20168 yr Clean little seats, Â that quite the compact design! Â I've been pondering the adjustable seats ever since I saw them in the Stephen wolf, Â still haven't gotten around to making one though :p I feel like this car is going to have more features than my last three cars combined haha. Â
December 2, 20168 yr Author I finally had the chance to build and testdrive the gearbox and shifting mechanism. And it works like a charm! I wanted to have 3 modules - front suspension, mid-section and rear suspension - that could be easily separated, but that reduced the overall stiffness of the chassis too much. So I ended up building the whole chassis around the gearbox and I'm really happy with the result. Shifting works very smooth and there is no substantial friction. Because of the drivetrain's simplicity you can hardly do anything wrong which would introduce serious friction. @brunojj1, I also managed to keep the mid-console 5 stud wide, although only in the area where the seats will be located. The whole chassis is still more rigid than I expected, but I will extend the mid-section to make it even more rigid later on. I really think this is my best work sofar. Next steps will be 1) moving the shift lever one stud backwards, 2) adding the engine and 3) adding the seats. The LXF-file of the current state can be found here. What do you think? Â Edited December 2, 20168 yr by Didumos69
December 2, 20168 yr I like this robust and elegant chassis very much - especially that simple but genious gearbox and shifter !  The last render looks really awesome! If you let me make another suggestion: IMO the seats would look better in another color than DGB - what about black?
December 2, 20168 yr I like it a lot Stiff chassis, but with minimal part usage. Proportions feel right. Excellent. You do have a lot of T-bone pieces though
December 2, 20168 yr Author 3 hours ago, brunojj1 said: I like this robust and elegant chassis very much - especially that simple but genious gearbox and shifter !  The last render looks really awesome! If you let me make another suggestion: IMO the seats would look better in another color than DGB - what about black? Thanks! You're right, the seats would look better in another color. Black doesn't look good in renders, but it's the most likely option in the real life build. However I don't have the right angled parts in black right now, so I will stick to DBG until I have decided about the final color scheme. 2 hours ago, Jeroen Ottens said: I like it a lot Stiff chassis, but with minimal part usage. Proportions feel right. Excellent. You do have a lot of T-bone pieces though Thanks! It may not surprise you that the T-bone piece is my favorite part , I use them for right angle rigidity. Btw, I know you are in pursuit of adjustable seats for your DB11. During my lunch break I had the time to mount one of my adjustable seats as well as the engine. But you probably want to make your own seats. The engine nicely covers the gearbox, but you can still look underneath to see what's going on in the gearbox. A few more images. Click on an image to enlarge: Edited December 2, 20168 yr by Didumos69
December 2, 20168 yr This is looking great, Â very robust indeed! Â You're making some very quick work of this chassis, Â I wish I was able to build at work ;) out of curiosity what's the width and length between the wheels?Â
December 2, 20168 yr Looking great. The only area that is questionable but maybe not since it looks to work ok is using a pin joiner to support the separate axles in the gearbox. It just seems that a bit to much torque could possibly make a gear slip since it isn't really a solid brace. Also, are you going to add a return to center system for the shifter? I only ask because it looks like you have to manually return it. I also notice that the driving rings are only engaging about halfway when they are shifted forward. It may be because the links you are using are not even?
December 2, 20168 yr Author 5 hours ago, DugaldIC said: This is looking great,  very robust indeed!  You're making some very quick work of this chassis,  I wish I was able to build at work ;) out of curiosity what's the width and length between the wheels? The length between the wheels is 39 studs (38 if measured heart to heart) and the width between the wheel hubs is 23 studs (22 if measured heart to heart). This is quite common for a 1:8 scale build. However, the car that I use as a reference (I won't tell), also for the position of the seats and steering wheel, is 4.5m long, has a wheel base of 2.7m and is 2.07m wide. Taking these measures into account my build is actually a 1:9 scale model. 2 hours ago, Meatman said: Looking great. The only area that is questionable but maybe not since it looks to work ok is using a pin joiner to support the separate axles in the gearbox. It just seems that a bit to much torque could possibly make a gear slip since it isn't really a solid brace. Also, are you going to add a return to center system for the shifter? I only ask because it looks like you have to manually return it. I also notice that the driving rings are only engaging about halfway when they are shifted forward. It may be because the links you are using are not even? You are right about the pin joiner. I have the habbit to use too many parts, so this time I made several iterations to remove unnecessary parts. But in this case I think proper bracing is more important, so that's what I will do. It's actually quite easy to do: About the return to center of the shift lever. I have been playing with this a lot. The operation of the shift lever just feels so 'right' that any addition meant to help the lever return reduces that 'feel'. It's also not really needed, because to complete a shift, it is not needed to return the lever. The return doesn't do anything. You can actually postpone the return until the next shift. So I decided to leave it like this. Another advantage is that I only need silicon bands for the 90 degree limiter. This video shows the exact behavior of the shifter: The driving rings are not engaged as far as for instance in the stock Porsche, but they are engaged deep enough to not slip. It's not because I use links with odd length, but because I extended the change-over catches deliberately with half a stud. Actually this has also been a result of a lot of trial and error. There are two advantages of this approach: 1) The red clutch gears won't get squeezed against their neighbouring liftarms (this happened in the Porsche and caused friction) and 2) The chances of double engaged gears during shifting is reduced. In the Porsche there is a short moment during shifting with two clutch gears being 'half' engaged, which may cause the gearbox to halt. By engaging the clutch gears a little less deep, there is a short moment of neither clutch gears being engaged instead, which is far less dangerous. Edited December 2, 20168 yr by Didumos69
December 2, 20168 yr They look like they are engaging properly when shifted back, but not as much when shifted forward, so are they rubbing the liftarms in the rear too much? And by the uneven, I meant because you have the steering links somewhat tapered inwards instead of being even, like they should be extended out a stud more on each side in the front. I thought that maybe this was causing the issue. I never noticed that the Porsche driving rings don't engage properly, I'll have to take a look. Edited December 2, 20168 yr by Meatman
December 2, 20168 yr Author 6 minutes ago, Meatman said: They look like they are engaging properly when shifted back, but not as much when shifted forward, so are they rubbing the liftarms in the rear too much? And by the uneven, I meant because you have the steering links somewhat tapered inwards instead of being even, like they should be extended out a stud more on each side in the front. I thought that maybe this was causing the issue. I never noticed that the Porsche driving rings don't engage properly, I'll have to take a look. Okay, now I understand what you mean. I watched the video again and see the difference too. Half a stud on each side should be enough to align the links evenly. Apparently it doesn't cause any trouble, but it would be nice to improve on this. I will look into it. Thanks. Edited December 2, 20168 yr by Didumos69
December 2, 20168 yr Sorry if it was mentioned already, but why don't you just use idle gears here: In the version on the left, the axles on the sides are fully static. If you have already tried these version, then sorry, they may not be the best (it's possible that they would introduce more friction, but it's hard to tell). But this could simplify things a bit.
December 2, 20168 yr Author 15 minutes ago, Lipko said: Sorry if it was mentioned already, but why don't you just use idle gears here: In the version on the left, the axles on the sides are fully static. If you have already tried these version, then sorry, they may not be the best (it's possible that they would introduce more friction, but it's hard to tell). But this could simplify things a bit. Thanks for thinking with me @Lipko . There were a few objectives I had in mind for this gearbox. One of them is that I didn't want red clutch gears to transfer drive on axles rotating at different RPM. This is a common practice, but from modding the Porsche I know it induces a lot of friction on the axles involved (see this post). So I wanted red clutch gears to only make dummy rotations when not engaged. The other objectives are that I want to cover a wide range of ratios. So not something like 1:2.5 upto 1:1, but rather something like 1:3:5 upto 1:0.8. And finally it all had to fit underneath the engine; I didn't want the gearbox to be wired through the entire chassis.
December 2, 20168 yr Author 5 minutes ago, Lipko said: Oh my, how stupid my left version is... Sorry for that, it doesn't even work. Haha, I thought I missed something, but the 24t side of the diff is not used, which can't be ok. The other version does make sense though, as long as you don't mind clutch gears transferring drive on axles rotating at different RPM. Edited December 2, 20168 yr by Didumos69
December 2, 20168 yr 1 hour ago, Lipko said: Oh my, how stupid my left version is... Sorry for that, it doesn't even work. Thanks ! And I scratched my head thinking "why am I so stupid, being incapable neither of comprehending nor coming to simple solutions like that myself"  ...  58 minutes ago, Didumos69 said: Haha, I thought I missed something, but the 24t side of the diff is not used, which can't be ok. The other version does make sense though, as long as you don't mind clutch gears transferring drive on axles rotating at different RPM. I think it´s worth to try this one in a motorized transmission - usually a differential doesn´t withstand much torque, but here it´s trapped between two axles... Edited December 2, 20168 yr by brunojj1
December 2, 20168 yr 5 hours ago, Lipko said: Sorry if it was mentioned already, but why don't you just use idle gears here: In the version on the left, the axles on the sides are fully static. If you have already tried these version, then sorry, they may not be the best (it's possible that they would introduce more friction, but it's hard to tell). But this could simplify things a bit. One of the unfortunate downfalls of the new style red clutch gear is that it is not compatible with the 16 tooth end of that differential..
December 3, 20168 yr Author 7 hours ago, Paul Boratko said: One of the unfortunate downfalls of the new style red clutch gear is that it is not compatible with the 16 tooth end of that differential.. Then I'm a lucky guy to have only normal 16t gears meshing with the 16t end of the diff .
December 3, 20168 yr The old one is compatible. Sorry for the wrong color, it's an old style in the schematic (LDD doesn't even let the new one mesh there).
December 3, 20168 yr 20 hours ago, Didumos69 said: How did you connect those two axle joiners? With a 2L axle? Why not use a 5.5 axle here? I really enjoy watching this WIP by the way. Together with the DB11 from @Jeroen Ottens two fun topics to followÂ
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