How much will it hold w/o bending?

[Artisan]

A folding brace is an interesting idea but it would be stronger as a triangular design.

The rectangular brace will keep the end vertical as the bar bends but won't do much to stop the bending.

View attachment 349456

Bruce

I fell asleep last night still pondering this stroke of genius !
Indeed a triangulation I believe would do more but still
if that is not thinking outside of the proverbial box I don't
know what is! It's "almost' Brilliant! ;-)

 

[Xfaxman]

That was weird, that image is now visible. It shows I actually am dealing w/ about
38" of square tube or square solid bar w/ about 7" extended off the end of that
equaling about 45" of cantilever.

I could go 2x4 if there is a 2.5 x 4.5 .25 wall counterpart to slip it into then redraw ALL. err.

It depends how tight it needs to be. I added a 4 foot long piece inside the shop crane boom, don't have a picture, but is this style.


Depending on the strength needed, you could use 2x3, 2x4, 2x5, or 2x6.

 

[Zick]

Can't help you but can't wait to see what you have up your sleeve. Your work has always impressed me and this looks interesting!

:thumbsup:

 

[the old grind]

Ok, now I'm picturing a boom that installs (vs telescopes) into the 'hitch receiver' plate for my SSQA. (lifting leverage at the rt end would be less that far from the pins) btw: The triangulation was fundamental to my initial vision and faded away as I drew anew. :mur:

(Guess the bright stripe is from not taping over the flash properly for closeups ... Doh!)

I gotta stick around to see what this turns into. It looks less and less like a QC buddy seat mount as we go along. Remote hydro pruning saw or digging arm/bucket to be added via the holes when we're ready to see more of the plan?

 

[Sodo]

A folding brace is an interesting idea but it would be stronger as a triangular design.
The rectangular brace will keep the end vertical as the bar bends but won't do much to stop the bending.

What you are doing with that upper tension link could reduce the rotation at the end after all the slop from all the joints are spent and the links are tight. But it won't reduce the bending much. You might as well use a chain or cable for that.

You need some triangles - those parallelograms won't help you. Just trying to repeat a little different what Bruce (above) said.

Here is an example of a design with triangles. You have to be sure that the 'boom' cannot slide back into its housing, it really has to be pinned there to pick up the strength of the cable truss, in other words if that cable can slack; the boom will bend.

 

[the old grind]

Heh.. Sodo, not meant to be 'paralellograms' ever. Your sketches are more clear, less confusing, show angles better for sure. (thanks!) Guess I could've used bigger paper, or drawn one sketch/page. ('long/short' was squeezed onto my grocery list ... covered 'milk, bread' with 2nd pic) :laughing:

Chain would work, allow adjustment. Didn't count on room to anchor either type behind the overlap of inner/outer booms, or above, so my (short) plate there. (No longer assuming they'd telescope ..) Might've shown a 30/60^ triangle config if OP had said there was room above that point to anchor to something there. (doh! .. tho' I did start off with "do you have room..?")

Sodo's sketch/layout looks good, doesn't it? Sub my (intended) fixed upper chain anchor point for his vertical link if needed. (high compression load there if as shown) Just un-pin 'boom' and chain/link from its end when dismounting. Enough of this folly, I say! We don't know if the OP can use any of this s__. (I'm sure he'll check in when he stops laughing .....)

 

[Artisan]

Not laughing T.O.G. I think it was a stellar idea.


But here is something to laugh at, more like CRINGE.

Gawd I was waiting for something
to SNAP and send shrapnel at high velocity into this guys gluts or knoggen.
If he keeps it up he will win the Darwin awards I think.
Shall we discuss "Deflection" ??? HA!

LOADING OAK.wmv - YouTube

 

[Artisan]

So....

If I use THIS calculator to determine the Moment of Inertia, then take that info to THIS calculator and punch it in I "think" I am getting some info I can work with. After
much to-do I am almost tripling the size of the stinger from 2" x 2" to 5" x 3", I may even bump up the width to 4". Understand
this is a stinger end, to a telescoping widget, (log loader+ deal) so it has to fit inside a much larger tube, it is really adding up in weight. If my
stinger O.D. is 5" x 3" the outer boom it slips into has to be 6" x 4" leaving .5"/2=.25" thick on all 4 sides to attach some
Teflon type of material so I do not have metal to metal grinding.

Here is the calcs for just the stinger using a 5" x 3" x .25" wall tube w/ a 45" cantilever and 1 ton of weight.
If I have done this right it says the 5x3 will deflect 0.17xxxx inches. Sounds acceptable to me. (I could bump
this up a bit "IF" I went w/ a thicker wall too. I sure wish I knew how to do this to the enith degree but I
do not and I think I would need a 4 year engineering course to understand it all!

I "said" there is 45" of cantilever, I think that statement is correct but in reality the stinger tube is 38" to the right of the outter tube plus some 1" thick plate at the end w/ holes in it AND there is 16" of inner stinger tube inside the outer tube. I may be calculating this all wrong but I kinda think I am well within safety margins providing I do not over power it. I want to be safe and not build a pos like in that last utube I posted a link to.

punt