A load cell; why didn't I do that before?!

Discussion in 'General Discussion' started by Navigator, May 5, 2021.

  1. Navigator

    Navigator Registered

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    Guys, I have to promote a load cell :)
    Honestly; WOW, what a difference that is!
    Maybe "you all" have one and right now think: "dude, you're OLD!" (Eh, I am)

    But for those who have none yet; go for it!
    I've got my G27 pedals hanging and already made a rubber block in there, but you keep depending on travel. That travel was less, so to get it right on the small part of that travel.....hmm.

    I found several tuts for building a load cell yourself, but the electronics were X on one site and Y on the other; I couldn't get it clear. Also; that board is SO small to solder on ;)
    And I would have to print a bottom half of the tube; I have no 3D-printer.
    I found a guy in Holland who makes the "one weight-scale/wheatstone bridge/bottom tube" all together as a package for 35 euro; that's mine! Two pot meters on it to set up everything just perfect, easy installation; very nice.

    So I thought I would have to get used to it; 2 laps!
    Man, what a difference that is. Judging to force needed is so easy.
    But what stood out the most to me; braking behind another car....... I ALWAYS had difficulties with that. It's even one of the reasons I don't do leagues or online at all anymore; I couldn't keep on going pushing cars out of the race.
    But this is so damn easy to judge, to "feel"......

    So; if you don't have a load cell; I would say go for it! Prices have dropped severely over the last year and a complete package for under 40 bucks is always out there; why not?!!
     
  2. davehenrie

    davehenrie Registered

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    I always wondered why, when I was one of the slower drivers out there, I would often ram a car I was following while braking for a corner. I think it was a combination of the rather long pedal travel & the lack of a load cell. I can't say I was focused on that issue, your comments brought it to the fore, but I seem to have done better in that area since I did get a load cell and limited the pedal travel. But nothing I can quantify. (now that I'm looking for it, I'll probably get worse rather than better...lol)
     
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  3. Navigator

    Navigator Registered

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    Hehe, sure; don't overthink it! You'll blame me for getting slower! :)
    I think, but that's just me and I probably think something different tomorrow, that it just feels more natural, could that be?
    Even in the proces of getting used to the load cell, it does.
    Look, coming from a good straight to a corner, just having the cell installed; you go for it and try it to death; you are bound to lock up because you are looking for that fine line and just want a bit over to see if it works, right?

    But then, when driving behind another car, you don't just stand on the pedal like it's going out of style; you are more prone to judge it, playing with it.......than it is a different matter.

    Ow well, now I'm overthinking it.......we should start a league together for guys who think so much, they can't drive anymore.
    Our first race is F1 at Spain and pole time will probably be in the 5 minutes :)
     
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  4. Highlandwalker

    Highlandwalker Registered

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  5. Lazza

    Lazza Registered

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    It's functionally no different to a super stiff spring installed instead of the default. Except if you do that you can keep a linear response, whereas the linked solution has a 2 stage resistance which you'll never be able to flatten properly in the game.

    Either get a stiffer spring and consider a new pot if it's acting up, or get a set of pedals with a load cell. Note I'm assuming the g29 doesn't have in-built compensation for its non-linear resistance, as that would make them half decent and even harder to mod.

    For load cells, I would aim for at least 45kg at the pedal, 60 or so would be good without being too demanding. Position and orientation of the LC can reduce the effective max load, both in mods and in bought solutions (like the t-lcm).
     
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  6. Navigator

    Navigator Registered

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    I did come across the True Brake mod and it seemed like a pretty decent mod.
    The way I got it; you still depend on travel, but they "zoom in" on the small travel you have left.
    That is actually a good idea I think, but you're still depending on moving parts and the thing that did it for me was the price.
    I mean, you are simulating a load cell with that mod while the real thing, is even cheaper.
    Going for force instead of travel, seems the proper way to me.
    But again; it is a nice piece of work and I suspect it being very good.

    The load cell I got in is a 50 kilo one.
    The guy said that would be enough if I wasn't a full time body builder.
    Well I'm used to get on the brakes like there is no tomorrow because of the fact I had a rubber block in there and thus depending on travel while that rubber block, was an ex motor mount. I have the pedals hanging and all thick steel construction; I can go wild without breaking something.
    But this cell; I can set the gain and set it so that I can't even get it on full if I was a horse from the waist down. (I wouldn't have time to race if I was; my wife would keep me busy I think.)
    So for me; 50 kilo is enough and I do apply a LOT of force. I didn't expect that.
     
  7. [NAR]Steve

    [NAR]Steve Registered

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    Which load cell mod did you get? I have a G920 on the way.
     
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  8. Navigator

    Navigator Registered

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    Hi Steve,

    I got one from the local "Ebay" here in the Netherlands (Marktplaats).
    It's the simple version; just the lower spring tube where you now put in the load cell; just a simple square thingy you buy at Ali for 2 bucks.
    Than a piece of electronics with two pot meters so you can adjust "it all".

    I tried to add a picture, but when I click that, I have to fill in a link.........don't know how that works (anymore?).......sorry.
     
  9. ThomasJohansen

    ThomasJohansen Registered

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    my g27 loadcell is a diy from a youtube tutorial. and even though its only 20kg it works very well.
     

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  10. JamesB

    JamesB Registered

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    I run True Brake on my G29, it is VERY good. It may not be a load cell but it behaves very much like one and means that your braking genuinely becomes about the force applied not distance travelled. I have used load cells in other engineering applications but I would suggest that there is very little between them and a True Brake setup.
     
  11. Navigator

    Navigator Registered

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    I believe you. You are the one who used both; I didn't. And as I said before; I'm pretty sure it must work well.
    But the section I underlined in your post; I can't really agree on. It still is a pot meter and that one does only depend on travel.
    Sure, with the rubber blocks, you have to apply more force to get more travel.......but we can spend weeks on that one; potato, potáto. ;)
     
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  12. JamesB

    JamesB Registered

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    I understand but the thing about True Brake is that its travel is much less than the standard pedal and as it travels the pressure required increases almost exponentially so that by the time you have reached maximum brake pressure you are really leaning on the pedal and it feels like a hard hydraulic pedal, so in that way it does become about the force applied not the distance travelled in terms of your muscle memory, much like a load cell. I genuinely think that there is very little to chose between the two. As you say its semantics really, the key is that these modifications have a HUGE impact on how you use the brakes and have helped my lap times and perhaps more importantly my consistency no end.
     
  13. EricW

    EricW Registered

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    A analog potentiometer is just a wiper on a coper track.
    Especially when you use a very limited area of the coper track it will wear out pretty fast and the output results will be inconsistent.
    Nowadays you see mostly hall sensors or accelerometers for rotation, and loadcells for pressure sensing in wear sensitive applications.
    The biggest advantage is no contact parts and consistency.
     

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