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BT Tech Stiffening plate

Discussion in 'Gen 2 Prius Accessories & Modifications' started by BethlehemPrius, Feb 4, 2007.

  1. Rest

    Rest Active Member

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    I am interested in this product, if they would just lower the price!
     
  2. MGM

    MGM New Member

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    <div class='quotetop'>QUOTE(Rest @ Mar 20 2007, 02:42 AM) [snapback]408833[/snapback]</div>
    The plate is beautifully machined, which obviously costs money. The photo below shows the stamped steel OEM plate on top and the aluminum BT plate below.
    [attachmentid=7060]
    I wonder if perhaps BT could save some production cost by eliminating the machining, leaving just a flat plate of anodized aluminum without the ribbed "XX" pattern that you see in the photo. You'd gain a few ounces in weight but cut production costs. Plus if anything the plate should be even stiffer with the extra metal. Hopefully, BT would then pass the savings on to its customers yet retain its profit margin. Just a thought.

    As is, it's a beautiful product that I found to be worth the cost of admission. But a lower cost would make it more accessible to more Prius owners.
     

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  3. Bill Merchant

    Bill Merchant absit invidia

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    By my simple minded reckoning, the BT Tech plate costs less than 1% of the cost of a Prius. I can't think of a thing in the tire/wheel/suspension system that costs less. Wait! Valve caps! THEY cost less, and good valve caps really make a difference in handling...
     
  4. daveleeprius

    daveleeprius Heh heh heh you think so?

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    <div class='quotetop'>QUOTE(Mean Green Machine @ Mar 23 2007, 11:12 PM) [snapback]411345[/snapback]</div>
    Without the machining and XX patterns, the plate would be 70% less strong and no better than the stock plate. The XX pattern increases strength without adding weight. That being said it's still too expensive for me at the list price. If there is ever another group buy, I may get one.

    Dave
     
  5. MGM

    MGM New Member

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    <div class='quotetop'>QUOTE(DaveLeePrius @ Mar 24 2007, 12:29 AM) [snapback]411406[/snapback]</div>
    Well I'm no structural engineer, but how is it that if you machine out metal from a thick plate, that's stronger than if you left the metal in that same thick plate?

    Here would be a cross section of the original thick plate before machining:

    **********************************************


    **********************************************


    Here would be a cross section of the machined out plate:

    *********\___________________________/*********

    _________/---------------------------------------------\_________


    I understand about losing a few ounces if you machine out the metal pits that form the XX. I don't understand how losing that metal from the pits makes it 70% stronger as you claim.

    Please explain for us non-engineering types. Thanks.
     
  6. Godiva

    Godiva AmeriKan Citizen

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    Perhaps it's less brittle so less likely to crack or snap?
     
  7. John in LB

    John in LB Life is good

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    <div class='quotetop'>QUOTE(Mean Green Machine @ Mar 23 2007, 11:55 PM) [snapback]411412[/snapback]</div>

    As an engineering type, I can tell you with certainty that you are 100% right - the only gain from removing the metal is weight reduction.

    I do believe that there should be some chassis stiffening benefits from this plate (I don't have one). However, I am unwilling to spend that amount of money for it.

    I am sure the price for the plate is not based on manufacturing costs - but rather what the market will bear. The best defense for that is competition. Does anyone know of an alternative source for this plate? Anyone have access to a machine shop - that can start stamping these things out?
     
  8. Bill Merchant

    Bill Merchant absit invidia

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    The OEM part is stamped out of sheet steel. The BT Tech plate is CNC milled and then anodized.

    Don't buy it if you don't want to. Your car already has the OEM brace, which is lighter weight. You don't need this.

    That way, there won't be a supply problem for those of us who can afford it and want to improve the handling of our cars.
     
  9. John in LB

    John in LB Life is good

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    <div class='quotetop'>QUOTE(Bill Merchant @ Mar 24 2007, 02:34 AM) [snapback]411437[/snapback]</div>
    Thank G-D it was computer controlled milling... I would hate to have someone do it manually. For goodness sake Bill, it's just a stiffening plate that goes under the car. Its not a piece of art.

    I am sure its quality workmanship - but I am a strong believer in function over form - especially when it comes to this purpose. If someone can find a way to make it simpler, easier, faster and cheaper - that would be great.
     
  10. itsme

    itsme New Member

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    <div class='quotetop'>QUOTE(John in LB @ Mar 24 2007, 07:02 AM) [snapback]411448[/snapback]</div>
    There is a company in Mexico Missouri who does waterjet cutting and does all kinds of items like this
    Jones waterjet cutting I think they are on the web. if contact them ask for jarrod he made my motor plate for my ev from scratch worked great first time plus other items. PLUS cost very reasonable
     
  11. FreshAirGuy

    FreshAirGuy New Member

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    Just got the BT plate. Installed it easily. Just wondering if two of the bolt heads recede and two protrude flush with the surface. It works great. Improves ride quite noticibly. Let me know if the bolt head configuration in the photo needs to be adjusted or if it is OK.

    Thanks!
     

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  12. MGM

    MGM New Member

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    <div class='quotetop'>QUOTE(FreshAirGuy @ Mar 24 2007, 06:20 PM) [snapback]411686[/snapback]</div>
    All four bolts were flush in my installation.
    [attachmentid=7082]
    Good luck!
     

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  13. malibucarl

    malibucarl Member

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    <div class='quotetop'>QUOTE(FreshAirGuy @ Mar 24 2007, 09:20 PM) [snapback]411686[/snapback]</div>
    Hi freshairguy,
    That's WRONG. The heads recede into the plate per the next post. Not an Engineer but structual integrity could be compromised.
    I sent Brian an email maybe he can see what's amiss.
    Carl
     
  14. BT Tech

    BT Tech New Member

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    UPDATE... We found that the only issue was not in the machining of the plate but the stainless washers that were shipped with some plates were one size too large.

    We will send out replacement washers to you right away!!




    <div class='quotetop'>QUOTE(FreshAirGuy @ Mar 24 2007, 10:20 PM) [snapback]411686[/snapback]</div>
     
  15. FreshAirGuy

    FreshAirGuy New Member

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    <div class='quotetop'>QUOTE(malibucarl @ Mar 24 2007, 10:51 PM) [snapback]411693[/snapback]</div>

    Thanks!

    <div class='quotetop'>QUOTE(BT Tech @ Mar 24 2007, 11:00 PM) [snapback]411697[/snapback]</div>

    Thanks!
     
  16. Rest

    Rest Active Member

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    <div class='quotetop'>QUOTE(John in LB @ Mar 24 2007, 06:23 AM) [snapback]411434[/snapback]</div>
    I've believed this from the beginning!

    So much for how great computer controlled milling is.
     
  17. donee

    donee New Member

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    Hi All,

    I think the problem to doing the plate as a one-off individual project would be the anodizing. The lot charge for one piece would kill any economic advantage. One might powder coat the plate if one has the equipment already. There are some garage/home shop powder coating equipment available. All one needs besides these is a surplus oven to reflow the powder. They do not recommend cooking food in an oven that has been used for the power coating reflow. So, unless your already set up for this, and the cost of the oven is applied to other projects, as well as a plate, power coating is also a non-starter economically.

    A flat plate would still need the areas milled out where the plate overlaps the bumps in the rail stampings on the car. And the counter bores are more easily machined with a spriral milling, although lots and lots of WD40 and wasting a new Forstner bit could work if your Drill Press has enough torque. So, that entails two setups (top and bottom). The other detail milling is probably similar in cost to the cost of the two setups. Leaving out the overlap areas might not result in as good results. Breaking down costs, 1/5 for overhead, 1/5 for rib milling, 1/5 for each setup and hole/recess milling and 1/5 for anodizing - all complete guessing, results in a 1/5 savings by leaving out the rib milling.

    As the car was not designed so that the plate is easily manufactured (socalled DFM or Design for Manufacture), there are some issues in making the plate cheaply. This is the nature of the beast I am affraid. The plate itself has to have features that accomodate the car, and that makes it more expensive.

    One way that might help, but would need to be analyzed, is rather than overlapping the bumps in the rails, cut out the plate in that area. This would avoid the top side (as mounted on the car) milling on a flat plate design. If the bumps push into that undercut portion of the plate, however, as part of its chasis stiffening improvement, then this idea would result in a plate that was ineffective.

    There is also the question if the flat plate be too stiff for the strength of the bolts and sheet metal its bolted into? One might use drilled holes instead of milled ribbing to tune the plate stiffness in a home-shop version. Mechanical engineering would be needed for the size and postion of the holes. If the cost of drilling and rib milling is the same, rib milling wins due to the marketing aspects of impressing the customer. One might also do singile sided rib milling, but this is a payoff only of one can prove the design works without the recesses over the rail bumps, and can then avoid the two-sided milling setups.
     
  18. John in LB

    John in LB Life is good

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    Don't make it too complicated. Just make it out of an aluminum plate. No variations in thickness required. Drill the 4 holes - I will concede that they should be countersunk... so a little extra cost here.

    Don't need to anodize aluminum - its not going to rust...

    I know its not as pretty, and it will weigh more than the one sold by BT (but it will actually be slightly stiffer - not that it will matter).

    This is a functional item and really has no aesthetic value - Beautification is just not required.
     
  19. TheAnnoyingOne

    TheAnnoyingOne New Member

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    <div class='quotetop'>QUOTE(John in LB @ Mar 25 2007, 10:12 AM) [snapback]411899[/snapback]</div>
    Here is a solution to stop nagging and get off our backs:
    Go to your nearest junk-yard; have them cut with a blow torch a piece of steel and drill 4 holes. Get 4 screws and washers from the Home Depot and you are done.
     
  20. MGM

    MGM New Member

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    <div class='quotetop'>QUOTE(John in LB @ Mar 25 2007, 10:12 AM) [snapback]411899[/snapback]</div>
    The plate is beautifullly machined. But it's also under the car where no one will see it. So I agree that beautification is not really required for this particular piece.

    As the owner of one, it's nice to know that it's there and that it looks good. But I'm the only one who'll know about it being there and looking good. Except for you guys/gals.