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Author Topic: Is this 'unfortunate' engineering  (Read 440 times)

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Is this 'unfortunate' engineering
« on: March 15, 2021, 03:13:59 pm »
  I don't th0nk I'm too fussy, but
this engines connecting rod is
offset with a universal-joint in
the middle.  Do I see a lot of slop
in the connecting rod, if not now,
soon?  This can't be a commercial
product.  I added a picture and link
to German EBAY.

I'm not unfamiliar with bad design. I
have some shelf-queens like that.
 
ebay.com/itm/Maschinenteil-einer-Dampfmaschine-steam-engine

Wayne

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Re: Is this 'unfortunate' engineering
« Reply #1 on: March 15, 2021, 03:47:39 pm »
I don't know Wayne, although it may look like a "U" joint,  I think it functions pretty much as say, a Jensen would , it just looks like a u joint, only difference is the connection rod is offset. It appears to only have 1 pin.
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Bruce, St. Paul Indiana, USA
"Originality thrives in seclusion free of outside influences beating upon us to cripple the creative mind."
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Re: Is this 'unfortunate' engineering
« Reply #2 on: March 15, 2021, 04:32:30 pm »
Not really a u-joint...just a lazy description.

Anyway, the line of force will not naturally go
in a curve, as it must in this case.  I'm sure
it would run, but it is not realistic in its
approach.  Makes as much sense as my 100yr-old
model with a steam-chest whose cover does not
come off for timing adjustments.

SMH,
Wayne
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Re: Is this 'unfortunate' engineering
« Reply #3 on: March 15, 2021, 08:52:30 pm »
Just a unjoint same as eccentic rod nothing unusual there but
Usually the piston rod is straight and the eccentic rod bent

Cheers
Dennis
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Re: Is this 'unfortunate' engineering
« Reply #4 on: March 16, 2021, 11:14:01 am »
Quote from: Scorpion2nz on March 15, 2021, 08:52:30 pm
Just a unjoint same as eccentic rod nothing unusual there but
Usually the piston rod is straight and the eccentic rod bent

Cheers
Dennis

Correct and agree - I would place the crank shaft bearing more to
the left and shorten the shaft. Then trying to bring the crank pin
in Line with the cylinder. A bent rod is just stupid...

Arnold
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Re: Is this 'unfortunate' engineering
« Reply #5 on: March 16, 2021, 12:09:39 pm »
  Thank you.  A bent connecting rod is just stupid!
It is, ultimately, not any better than pushing on
a string, something my German-style first-semester
physics teacher explained was impossible (the
subject was 'statics').

  If anyone is interested, the next case of bad design
is the Elektro.  I love it but want to go back in time,
call in the designer, and say 'What were you thinking',
in regards to both the piston and valve rods.

  If this thread continues, my Empire complaints are next.

Anyone can add their two-cents regarding bad design in
other engines.   

Wayne
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Re: Is this 'unfortunate' engineering
« Reply #6 on: March 16, 2021, 05:57:12 pm »
An offset connecting rod on a model such as this probably has little to no effect on its performance,  it would be relying on the bolt to axle disc to keep it more rigid than it should, & wear a bit more laterally on the connecting rod and steam gland than it should. I'd buy this should it come up for sale just for the oddity of it.
A full size engine would/should never have such a configuration.
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Bruce, St. Paul Indiana, USA
"Originality thrives in seclusion free of outside influences beating upon us to cripple the creative mind."
  Nikola Tesla
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