[TheForge] treadle hammer anvils

Fri Jan 10 11:30:01 2003

Bob,

Clay Spencer has made humoungous contributions to the blacksmithing =
community, not the least part of which his treadle hammer workshops.  I =
would wager that most of the Spencer treadle hammers (of both sorts) were =
fabricated in these sessions.  The immense publicity resulting from so =
many such treadle hammers in turn may have persuaded others to build the =
same sort of hammers.  Furthermore, Clay began this effort before the =
Grasshopper was more than a gleam in my eye.  His vertical-motion hammer =
was one of the principal inspirations for the Grasshopper design.

By contrast, I have helped build only one Grasshopper (the prototype).  I =
have not even constructed one for myself, simply from lack of time and =
energy.  (I can use the prototype any time I like.)  I have done nothing =
to publicize it, other than the website and a few newsletter articles.  I =
have no intention of holding Grasshopper-building workshops.  Despite that =
"handicap" at least a dozen plans have been sold at $25 each, and at least =
two hammers are under construction.

That's the immediate reason for the disparity in numbers, and for the =
likely continuation of that disparity for the forseeable future.

I won't know whether Phil was being snide or not unless he responds.  The =
written word can put more import into an offhand remark than was ever =
intended.  Flame wars start this way - fortunatly seldom in this group. =
=20

Bruce
NJ

>>> [email protected] 01/10/03 09:41AM >>>
bruce,

no doubt you are correct but...how many spencer style swing arm hammers do =
you think have been built? how many grasshoppers?

'how many' may not be an indication of 'how good' (they sell truckloads of =
twinkies) but it is an indication of something.

i didn't think phil was denigrating your grasshopper or being snide. he =
was just posting his preferences. that's okay.

thanks for your comments on this subject.

bob s.
________

>As the designer of the Grasshopper, I have to take issue with this =
statement.  I'm not at all impressed by your denigrations of the machine.  =
 I don't know whether you intended to be snide, but that's how it comes =
across in writing.
>
>The Grasshopper is a very simple design.  If you think it's complicated, =
you haven't looked past the surface.  Most of the seeming complication is =
really (1) the two front-mounted adjustment (which I consider very =
important safety features, but which could be simplified considerably by =
making them accessible only closer to the points of their actions, and (2) =
the small additional complication of the apparatus (eccentric pulley) that =
renders the ram completely weightless. =20
>
>In judging the complication of a machine, consider the MOVING parts.  In =
the case of Spencer-type swing-arm hammers, there are six moving parts:  =
Ram, two arms, treadle, connecting rod, and spring(s).  In the case of the =
Grasshopper, there are 8 moving parts:  Ram, two arms, two cranks, two =
struts, treadle, treadle pulley and cable, and spring(s).  In the Spencer =
vertical TH, there are 14 moving parts:  Ram, 8 guide wheels, one arm, one =
strut, treadle, connecting rod, and spring(s).  (I've counted multiple =
springs as one moving part because in principle a single spring could =
replace multiple springs.)  Both the Spencer-type hammers and the =
Grasshopper hammer have adjustments. =20
>
>On the Spencer-type swing arm machine, the head height and the connecting =
rod can be adjusted, but only from the side.  On the Spencer vertical-motio=
n machine, the connecting rod can be adjusted, but only from the side.  On =
the Grasshopper, there is no need to adjust either of these, but the =
treadle height and the "kickback force" (needed only in a weightless =
treadle hammer) are adjustable from the front.  My principal reason for =
placing these at the front, at the cost of a few more parts and a  little =
more effort in fabrication, was to avoid the devastating accidents that =
can happen while adjusting a treadle hammer.  Safety first.
>
>If you think these "complications" aren't worth the trouble, then you're =
fooling yourself.  (You're free to fool yourself as much as you wish, just =
don't expect to propagate it over this group without rebuttal.)
>
>BTW, many of us have gimpy knees, rendering TH's difficult to use at =
best.  The Grasshopper is by far the best treadle hammer for persons who's =
knees are no longer as good as they were at age 20.
>
>Bruce Freeman
>NJ
>
>>>> [email protected] 01/09/03 06:26PM >>>
>Hi Bob -
>
><snip>
>    The grasshopper is to darn complicated a contraption(I spend most of =
my
>time in hi-tech advanced manufacturing and automation) and I guess I like
>things simple when I'm home in the shop. It looks like a nice science =
fair
>project. If you want to diddle, then the grasshopper will be interesting.
>Keep it simple. The leg exercise you get will be a benefit anyway - heck,
>I'm gettin' older and my wife seems to be gettin' faster!! :o))
><snip>
>
>
>_______________________________________________
>http://mailman.qth.net/mailman/listinfo/theforge=20
>theforge mail list group photo site is
>http://www.photoaccess.com=20
>Login:  [email protected]=20
>password:  anvil
>___________

_______________________________________________
http://mailman.qth.net/mailman/listinfo/theforge=20
theforge mail list group photo site is
http://www.photoaccess.com=20
Login:  [email protected]=20
password:  anvil
___________