tool for pinching the end of a steel rod?

Have a question or want to show off your project? Post it! No Registration Necessary.  Now with pictures!

Threaded View
Is there a tool that puts tremendous force on metal, like to pinch the
end of a steel rod so that it flattens out a little?

If it's well-known, I guess all I need is the name.

I would like to put the steel rod through a hole and then pinch the end
of the rod so that it does not come out of the hole.

I picked up a bolt cutter thinking it might compress the steel rod as
it cuts. But it actually stretched the end of the steel rod so that the
diameter was less after the part broke off. I guess a powerful enough
bolt cutter with a dull attachment on the end?

Thank you.






Re: tool for pinching the end of a steel rod?

You should be able to adjust the cutting head on your bolt cutter
so that it does not cut through the rod, but rather just mashes
the end.

A sledge hammer and an anvil or other heavy steel block to strike
the rod on.

The next step might be a shaped anvil in a hydraulic press.

If you have a bunch to do, look into punch press.

(top posted for your convenience)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Keep the whole world singing . . . .
DanG  (remove the sevens)
dgriff237@7cox.net



Quoted text here. Click to load it



Re: tool for pinching the end of a steel rod?

Quoted text here. Click to load it

Thanks, I'm encouraged that it will work. I'm thinking maybe to flatten
grind part of the bolt cutter jaws.

I would like to be able to do the pinching when the rod is in place (I
can't do that on an anvil).

Re: tool for pinching the end of a steel rod?
John Doe wrote:
Quoted text here. Click to load it
The best question is why?
What is the application??

There are things like roll pins, tapered pins, welders, and...
the friction fit (also can be done as the heat one part, freeze the other!)

A hydraulic press and the two parts made the right size should do the
trick... of course this depends on the application.

And, also does the pin need to rotate free or not?

      :- )

           _-_-bear

Re: tool for pinching the end of a steel rod?
John Doe wrote:

Quoted text here. Click to load it

This could be done in a few seconds with an oxyacetylene torch and a hammer.
Heat the end of the rod to red (won't take very long with a real O/A torch), put
steel block up to the back of the rod, WHACK the end is flat. Even easier if you
have an anvil or substitute.

GWE

Re: tool for pinching the end of a steel rod?
Do you have a bench vise?

Lewis.


Re: tool for pinching the end of a steel rod?

Quoted text here. Click to load it

Partly out of curiosity and very generally/typically speaking.
Which, bolt cutters or a vise, is able to apply more pressure?

I've seen pressure data for vises, but I suspect that information
isn't usually given for bolt cutters.

Re: tool for pinching the end of a steel rod?

Quoted text here. Click to load it

This would be a matter of the construction of the bolt cutter and the
strength of the individual, versus the limiting strength of the vise - I
assume that the strength of someone turning the vise handle would not be
limiting.

Raw guesses:

Assume

a) the bolt cutter is a two-handed type with handles 20 inches from the
pivot, and the jaws 2 inches away
b) the strength of a pair of arms squeezing together is similar to that for
the press-up motion
c) the person operating the bolt cutter can do a single press-up with a
weight equal to his own on his back
d) the person weighs 150 lbs

then the force at the jaws is about a ton and a half.  Get a big guy mad and
a bigger bolt cutter and maybe you could get close to ten tons.

The last time I broke a vise the casting broke, but I don't want to bother
doing that math, so instead I looked up the strength of a 3/4 inch grade 5
bolt as that would be a typical small vise size; it's roughly 20 tons.



Re: tool for pinching the end of a steel rod?

Quoted text here. Click to load it

Then factor in the difference in force-per-square-inch applied to the
rod by a narrow bolt cutter jaw vs a wide vice jaw.

Quoted text here. Click to load it


Re: tool for pinching the end of a steel rod?

Quoted text here. Click to load it

Ooo, err, that'd make a hulluva big difference.

(now remembering some possibly-true story about fat ladies, stilletto heels,
and aeroplane floors...)



Re: tool for pinching the end of a steel rod?
In article <pkEhf.4052$43.1039@nnrp.ca.mci.com!
nnrp1.uunet.ca>, jtaylor@deletethis.hfx.andara.com says...
Quoted text here. Click to load it

You're comparing apples and oranges here - the mechanical
advantage of a bolt cutter to the ultimate strength of the
screw in a vise. Also neglected is the fact that bolt
cutters use compound leverage to generate the cutting
force.

I just took a few quick measurements from a pair of 30"
bolt cutters and a 4" Wilton bench vise. I get about a 65:1
mechanical advantage for the bolt cutters, and approx 170:1
for the vise. Taking into account the fact that an acme
screw might be 40% efficient on a good day, the MA of the
two tools is not all that different.

Ned Simmons

Re: tool for pinching the end of a steel rod?

Quoted text here. Click to load it

Try rotating the bolt cutter 90 deg so it is trying to split the rod
lengthwise.

--
Free men own guns, slaves don't
www.geocities.com/CapitolHill/5357/

Re: tool for pinching the end of a steel rod?
In article <nhull-DF07C7.07383625112005
@news1.east.earthlink.net>, nhull@access4less.net says...
Quoted text here. Click to load it

And the reason this is a great suggestion is obvious to
anyone who has done any smithing with a cross pein hammer.

Ned Simmons

Re: tool for pinching the end of a steel rod?
Quoted text here. Click to load it

It sounded really great to me. But my metal doesn't cooperate, it
crumbles instead of bends. I tried cutting a slot in the end of the
rod, but it still breaks when the bolt cutter is used to separate
the two halves.

I only need to do this twice, so (instead of flattening my bolt
cutter blade) I might spin the rod against a rotary tool cut off
disk to make a slot, then cut a notch in a washer and crimp the
washer into the slot. A washer crimps surprisingly well.

Thanks for all the interaction, bye.

Re: tool for pinching the end of a steel rod?
Depending on the application it would be easier to hammer on an axle
cap (I don't know what they are really called) and possibly weld it or
solder it in place.

If this is a production job there is a die set for an ironworker that
does what you want.


Site Timeline