Popular Post supercurio Posted June 27, 2021 Popular Post Share Posted June 27, 2021 (edited) Hi guys! Since the initial attempt at fixing the BT LOY / BT LOU / BT LOW issue by Leaperkim, by removing some of the ridges on the inside of the cover doesn't appear to be sufficient as experienced by @shellac, I started experimenting with the design of a support to mitigate the issue and hopefully reduce the risk of failure. The concept is simple: adding a couple spacers between the center of the side covers and the pedal hanger & inner shell. There seem to be a trend between failure and use of power pads which may transfer excessive force onto the battery packs, including on the jumping pad area and above which is often the most rigid and widest. I received my wheel yesterday and pretty determined to get this reinforcement ready before slapping power/jumping pads on. Here's the result of today's work: The low support rests indirectly on the pedal hangers. The high support is higher up where a bunch of the cover is unsupported as well. The lower area is covered by the pedals, so it's likely unnecessary. Supports use arches to be rigid and light Supports don't require to remove the side cover ridges Rounded corners should avoid excessive stress and cracking of the inner or outer shell. I'm printing now this first design to check out dimensions and tolerances, and will follow up on how it goes. While I'm working on it: would you have warnings, advice or suggestions? As soon as I get a design that works, I'll publish on Thingiverse with the source (Freecad file) Edited July 8, 2021 by supercurio 4 1 Quote Link to comment Share on other sites More sharing options...
Planemo Posted June 28, 2021 Share Posted June 28, 2021 7 hours ago, supercurio said: While I'm working on it: would you have warnings, advice or suggestions? I think the idea is sound tbf, good work! Your inserts would only need to be a couple of mm above the height of the packs I guess, so shouldn't bow out the centre of the panels, I doubt you would even notice. I think I would still be happier removing the ribs anyway, especially on the left pack (in your pic) as the bms components are towards the edge of the wheel rather than the centre where your inserts provide the most clearance. 1 Quote Link to comment Share on other sites More sharing options...
null Posted June 28, 2021 Share Posted June 28, 2021 Nice, it could be combined with reducing all the ribs by 1-2mm (sanding machine?) 1 Quote Link to comment Share on other sites More sharing options...
supercurio Posted June 28, 2021 Author Share Posted June 28, 2021 Thanks for the feedback, yes good point, it could be combined with reducing the ribs. Once the clearances are adjusted, these should compensate for the reduce stiffness. I guess there's a trade-off here between stiffness and depth of the ribs; hard to tell since we don't know for sure if the damage is done by the ribs or by pressure making the whole board flex and break eventually. I tested the concept with the first print and it looks good, however there are a few dimensions to adjust: time to iterate! Then I think I'll design a couple extra support points to be installed just above the packs, a location that matches roughly where the top of the pad's throttle and break can hit harshly in case of a fall. How it looks for now - printed in transparent PETG. Print settings make them overkill strong. 2 Quote Link to comment Share on other sites More sharing options...
Planemo Posted June 28, 2021 Share Posted June 28, 2021 46 minutes ago, supercurio said: Once the clearances are adjusted, these should compensate for the reduce stiffness. Even with all the ribs removed that are likely to hit BMS components, there is no reduction in stiffness to any noticeable degree. I did this on my own Sherman. 46 minutes ago, supercurio said: hard to tell since we don't know for sure if the damage is done by the ribs or by pressure making the whole board flex and break eventually. I really don't think that overall pressure on the BMS is the problem, it's just the area where the components are. There really isn't any other area on the board that could get damaged. The board itself is pretty tough (I have worked around GW boards which are virtually identical) and aside from the components they are essentially a large, empty piece of flat, fibreglass board. Because of that, I think your (very nice) spacers might actually be overkill and may not help anything above and beyond simply taking out the required ribs. The only area left not helped by removing ribs is a small section on one of the packs where the recesses are, moulded into the side panels at the front and rear. These recesses are however flat so will not make a single, localised pressure point on a component like the ribs do. It is this one area that your spacers might help, providing they are tall enough to raise the recess section away from the pack, not easy when the recess is so close to the edge of the panel (and fixings)... 1 Quote Link to comment Share on other sites More sharing options...
Planemo Posted June 28, 2021 Share Posted June 28, 2021 Dont know if it will help but heres a pic showing the areas of ribs I have completely removed. To the best of my knowledge (ie without stripping the packs and taking exact measurements of locations of components) the areas I have removed encompass ALL the components on the BMS's on both packs. As I say, the only small areas left that I am unsure on is the flat recessed sections but I think its pretty safe, as they are lower than any of the ribs were. 2 Quote Link to comment Share on other sites More sharing options...
supercurio Posted June 28, 2021 Author Share Posted June 28, 2021 Oh these ribs as well, thanks for showing. In case it helps, here's a new video where a pack gets opened, it give a good look of the cells and BMS arrangement Quote Link to comment Share on other sites More sharing options...
Planemo Posted June 28, 2021 Share Posted June 28, 2021 I already had pics of the BMS, thats how I came to my decisions on where to remove ribs. What I was trying to say is that until I strip the packs myself (or I am provided with exact measurements/locations of the components) I cannot do any more than I have done already, which I am fairly sure encompasses all the components anyway. 2 Quote Link to comment Share on other sites More sharing options...
supercurio Posted July 3, 2021 Author Share Posted July 3, 2021 Quick update: I have working block prototypes for the left side, with adjusted dimensions and tolerances: promising! However yesterday I swapped the tire and remembered that... okay yeah: there are wires on the right side . So a few more adjustments will be needed to keep the same blocks on both side, I hope to do that this week-end. 2 Quote Link to comment Share on other sites More sharing options...
Popular Post supercurio Posted July 5, 2021 Author Popular Post Share Posted July 5, 2021 Progress today: I modified the arch to have the right amount of room for motor wires, reworked a bunch of shapes and tolerances. Getting close. 4 Quote Link to comment Share on other sites More sharing options...
Popular Post supercurio Posted July 6, 2021 Author Popular Post Share Posted July 6, 2021 (edited) I got the low one dialed-in finally. It works well even the extra shrink wrap tube that I added around the wires after changing the tire and denting the original one wrap. It fits just right on the cover between the ribs, the height also seem good to keep the cover pressed out slightly in the middle. Now, onto the higher support. Edited July 6, 2021 by supercurio 5 Quote Link to comment Share on other sites More sharing options...
Popular Post supercurio Posted July 8, 2021 Author Popular Post Share Posted July 8, 2021 Now published on Thingiverse, https://www.thingiverse.com/thing:4903290 More details tomorrow. 8 Quote Link to comment Share on other sites More sharing options...
Popular Post RockyTop Posted July 22, 2021 Popular Post Share Posted July 22, 2021 These really do work great. It adds strength to the center of the cover. The lower support is only an inch away from the biggest problem area. The lower support translates the outer force from the cover to the pedal hangers very nicely. 5 Quote Link to comment Share on other sites More sharing options...
Planemo Posted July 23, 2021 Share Posted July 23, 2021 I really wish someone in the UK could print these up and supply. I dont have a printer and trying to get anything printed off in small quantities seems to be really expensive when I last looked. I wonder if theres an EUC'er on the forum who say might be prepared to make full sets, charge whatever they need to cover their time/parts and maybe add a little more on top for Supercurio to make a couple of beers from. I could prob use 4 sets for myself and a few friends. Even with modded panels, I reckon these are worth having 1 Quote Link to comment Share on other sites More sharing options...
COMMANDOF4 Posted July 31, 2021 Share Posted July 31, 2021 CAN WE BUY THESE YET? COMMANDOF4@GMAIL.COM Quote Link to comment Share on other sites More sharing options...
Rawnei Posted July 31, 2021 Share Posted July 31, 2021 7 hours ago, COMMANDOF4 said: CAN WE BUY THESE YET? COMMANDOF4@GMAIL.COM You have to find somewhere to print it for you, for instance in Europe there is smartwheels, I'm sure there are similar services closer to you. Quote Link to comment Share on other sites More sharing options...
supercurio Posted July 31, 2021 Author Share Posted July 31, 2021 Yes you should be able to buy them from @RockyTop soon. (I'll answer to your PM within the next few days @RockyTop and thanks for the great video!) 1 Quote Link to comment Share on other sites More sharing options...
supercurio Posted March 30, 2022 Author Share Posted March 30, 2022 Kevin from EUC UPGRADES / Erides.co.uk showed the supports on his channel 1 Quote Link to comment Share on other sites More sharing options...
Irawan Posted June 17, 2022 Share Posted June 17, 2022 My sherman bought on December 2021 turns out already has plastic protruding in the middle, I guess it's mimicking supercurio's 3d design. I wonder which year did you guys bought the sherman? 3 Quote Link to comment Share on other sites More sharing options...
lazybones99 Posted August 25, 2022 Share Posted August 25, 2022 Anyone know if these would be helpful and/or fit on the Sherman Max? I think some of the problematic ribbing is removed on the max so I’m not sure if it matters. Quote Link to comment Share on other sites More sharing options...
fbhb Posted August 25, 2022 Share Posted August 25, 2022 2 hours ago, lazybones99 said: Anyone know if these would be helpful and/or fit on the Sherman Max? I think some of the problematic ribbing is removed on the max so I’m not sure if it matters. No need whatsoever on the Max, as you state yourself in your post, there are NO ribs on the side panels of the Sherman Max and Also "standoffs" are built in as well! 2 Quote Link to comment Share on other sites More sharing options...
lazybones99 Posted August 25, 2022 Share Posted August 25, 2022 Thank you! Quote Link to comment Share on other sites More sharing options...
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