Great transom saver

  • suzuki
    Woodbury, Mn
    Posts: 18621
    August 9, 2012 at 9:48 pm #1091162

    Quote:

    Quote:

    So Danno, I apologize for the pictures but, you’re saying these two diagrams are equivalent???

    Yes.

    You are assuming there is a vertical force component (other than gravity) to the lower unit (i.e. bouncing), and that’s why this entire conversation always goes off on a tangent….people imagine that the engine is bouncing all over the place. If that were the case then yes, I would rather have the bar type. But the simple fact remains that if there is little to no movement they both do the same job because when there is no bouncing it is identical to the boat sitting there in your garage not moving. The engine and boat are “one”.

    Once again, if the engine doesn’t move or move excessively, then the wedge performs the same function as the bar type.

    Quote:

    Whether it matters or not, I don’t know. but I do know this, my brand new wedge is for sale if you want to buy it.

    No thanks. I already have one I don’t use.

    What about the kinetic energy of the shaft and lower unit created when hittng bumps in the road? That energy is either being solely transmited through the transom (kinda up and back) or shared with boat frame. (straight up on transom but far less force than before) Your serve.

    ottomatica
    Lino Lakes, MN
    Posts: 1380
    August 9, 2012 at 10:31 pm #1091168

    Danno, I’m more worried about the moment imparted on the transom via the motor which is happening all the time because:

    1. Transoms are usually angled

    2. It’s unlikely that the center of gravity of the motor is directly above the revolute joint of the motor’s tilt/trim mechanism, hence in Suzuki’s example, vertical acceleration creates a moment.

    3. There are all sorts of other forces that are imparting themselves on the transom during transport. Any other assumption is truly too simplified.

    The transom saver with it’s placement and great mechanical advantage reduces that moment, the wedge reduces…ZILCH.

    danno
    Central MN
    Posts: 323
    August 9, 2012 at 11:06 pm #1091174

    Once again, you are ignoring the most important piece of the puzzle here: there is no force imparted on the transom if the engine isn’t moving other than the weight of the engine itself, and that weight is static regardless if the boat is moving or not.

    If the engine isn’t moving/bouncing, then the difference between a wedge and bar transom saver is…ZILCH.

    biggill
    East Bethel, MN
    Posts: 11321
    August 9, 2012 at 11:25 pm #1091181

    Quote:

    Quote:

    For you guys that are engineers, I’ve very suprised that you assume the benefits without any real hard test data.

    Engineers don’t have enough spare time to get hard data for a discussion like this. That’s ridiculous. We’re spending our time doing Waterfowl AIS studies.

    So Danno, I apologize for the pictures but, you’re saying these two diagrams are equivalent???

    In simple terms, in the third pic you will see that with a force applied perpendicular to the transom upon the motor that there will be a moment generated on the transom of the Force times the distance to the bottom of the transom plus a shear force equivalent to the force.

    In the fourth pic the moment and the shear force will be shared by the transom and the transom saver.

    I don’t deny that the wedge helps the transom but I strongly contend that the transom saver does more for your transom than the wedge by a long shot.

    Whether it matters or not, I don’t know. but I do know this, my brand new wedge is for sale if you want to buy it.

    So we agree to agree.

    Agreed!

    I knew I could get one of you engineers to put it on paper. It doesn’t take much to get a rise out of you guys.

    Which is why I know BK isn’t really an engineer.

    He’s as cool as a cucumber.

    ottomatica
    Lino Lakes, MN
    Posts: 1380
    August 9, 2012 at 11:27 pm #1091182

    Danno, trailers bounce while you tow them.

    I don’t know what else I can tell you

    F = ma?

    Do I need to make a model and run a sim for you?

    biggill
    East Bethel, MN
    Posts: 11321
    August 9, 2012 at 11:35 pm #1091180

    Danno,

    Think of it this way, you are the transom and you a holding a very heavy motor above the ground with your hands.

    Would you rather have the motor supported by a device that is connected to the ground, or by a device that is mounted to your legs? Then add an earthquake.

    The one mounted to you legs is going to help stabilize, but you ( the transom) will still be taking all the force.

    The one mounted to the ground, will be stabilized as well but will share the shock loads.

    danno
    Central MN
    Posts: 323
    August 9, 2012 at 11:41 pm #1091187

    Quote:

    Danno, trailers bounce while you tow them.

    But with the engine secured it bounces in sync with the trailer/boat. They are “one”.

    But, if you don’t agree with that, why would you then put a solid link between said bouncing trailer and lower unit???

    biggill
    East Bethel, MN
    Posts: 11321
    August 9, 2012 at 11:43 pm #1091188

    Quote:

    And by the way, which way does the force point on flat ground during acceleration/deceleration of your vehicle?

    That all depends if it’s a Ford or Chevy. A Chevy’s force is negligible.

    suzuki
    Woodbury, Mn
    Posts: 18621
    August 10, 2012 at 12:04 am #1091190

    I think we’ve reached the point where we need a rocket scientist!

    biggill
    East Bethel, MN
    Posts: 11321
    August 10, 2012 at 12:14 am #1091179

    Quote:

    I think we’ve reached the point where we need a rocket scientist!

    Pug? Where’s Pug?

    ottomatica
    Lino Lakes, MN
    Posts: 1380
    August 10, 2012 at 12:22 am #1091196

    Quote:

    Quote:

    Danno, trailers bounce while you tow them.

    But with the engine secured it bounces in sync with the trailer/boat. They are “one”.

    But, if you don’t agree with that, why would you then put a solid link between said bouncing trailer and lower unit???

    Without the transom saver, the engine/transom is allowed to flex freely (in a momentary sense), the added support hinders this motion, reducing stress.

    danno
    Central MN
    Posts: 323
    August 10, 2012 at 12:43 am #1091201

    Quote:

    Without the transom saver, the engine/transom is allowed to flex freely (in a momentary sense), the added support hinders this motion, reducing stress.

    Exactly! And that’s why a wedge or bar transom saver is used.

    fishnutbob
    Walker, Mn.
    Posts: 611
    August 10, 2012 at 1:47 am #1091161

    You guys are doing a great job debating this. Lets hear more

    big_g
    Isle, MN
    Posts: 22454
    August 10, 2012 at 1:49 am #1091205

    Leave your boats in one lake… your just spreading AIS moving around

    Joe Scegura
    Alexandria MN
    Posts: 2758
    August 10, 2012 at 3:22 am #1091232

    Ottomatica and Suzuki, I think we’ve done all we can do. If I had the time I’d run this on my FEA program to prove it but for some reason I think the answer would be something like… your missing the point! We’ll I guess we’re all missing the point.

    I showed this thread to another Engineer today and I quote… “wow, this guy couldn’t be more wrong and yet he believes so strongly he’s right.”

    As Bob said, great debate guys It was entertaining.

    big_g
    Isle, MN
    Posts: 22454
    August 10, 2012 at 12:22 pm #1091267

    I showed this to one of my dumb buddies and he laughed about how people think their transom takes a bigger beating on the trailer, than it does in Lake Erie…

    Brian Klawitter
    Keymaster
    Minnesota/Wisconsin Mississippi River
    Posts: 59992
    August 10, 2012 at 12:37 pm #1091270

    The FW is mad at me…

    “I’m coming to bed in a while. This guy on the internet is WRONG!!”

    Brian Klawitter
    Keymaster
    Minnesota/Wisconsin Mississippi River
    Posts: 59992
    August 10, 2012 at 12:41 pm #1091273

    Quote:

    Non-engineers always try to cover their with comments like these too…

    “That’s what I would say too if I were in your shoes” ~© Tim Miller aka Millerman 2008

    targaman
    Inactive
    Wilton, WI
    Posts: 2759
    August 10, 2012 at 2:22 pm #1091319

    I have bad gas today.

    Brian Klawitter
    Keymaster
    Minnesota/Wisconsin Mississippi River
    Posts: 59992
    August 10, 2012 at 2:23 pm #1091320

    We know…it’s bad virtual gas.

    crossin_eyes
    Lakeville, MN
    Posts: 1379
    August 10, 2012 at 2:26 pm #1091325

    And for bad gas….the wedge is arguably better.

    Brian Klawitter
    Keymaster
    Minnesota/Wisconsin Mississippi River
    Posts: 59992
    August 10, 2012 at 2:27 pm #1091326

    Don’t need to be no engineer to figure that one out! LOL!

    targaman
    Inactive
    Wilton, WI
    Posts: 2759
    August 10, 2012 at 2:30 pm #1091327

    Quote:

    And for bad gas….the wedge is arguably better.

    Has there been a scientific study that proves this?

    Brian Klawitter
    Keymaster
    Minnesota/Wisconsin Mississippi River
    Posts: 59992
    August 10, 2012 at 2:49 pm #1091336

    No, but I’ve seen the commercial.

    targaman
    Inactive
    Wilton, WI
    Posts: 2759
    August 10, 2012 at 3:05 pm #1091344

    I just talked with Big G’s dumb buddies and they agree.

    big_g
    Isle, MN
    Posts: 22454
    August 10, 2012 at 3:48 pm #1091359

    Quote:

    I just talked with Big G’s dumb buddies and they agree.

    Vicious circle isn’t it…

    1hl&sinker
    On the St.Croix
    Posts: 2501
    August 10, 2012 at 4:10 pm #1091370

    So! Which is better? The bar or the Wedge.

    suzuki
    Woodbury, Mn
    Posts: 18621
    August 10, 2012 at 4:12 pm #1091371

    Quote:

    So! Which is better? The bar or the Wedge.

    Drew Engelmeyer
    Lakeville, MN
    Posts: 359
    August 10, 2012 at 4:20 pm #1091375

    Quote:

    … and the fact the there’s no rubber foot rubbing paint off my lower unit.

    That just pisses a guy off…

    big_g
    Isle, MN
    Posts: 22454
    August 10, 2012 at 4:29 pm #1091377

    Quote:

    So! Which is better? The bar or the Wedge.

    I have been very clear…. I couldn’t tell you anything about the 2 types… other than your transom takes way more “abuse/stress” or whatever, motoring across a choppy lake than it ever will on a trailer, on a decent road (minimum maintenance roads excluded)

Viewing 30 posts - 61 through 90 (of 108 total)
1 2 3 4

You must be logged in to reply to this topic.