anvilfire! Power hammer Page!
Catalog of User Built Hammers
A Spring Helve hammer built by Jeff Reinhardt AKA "Ptree"

Man and Machine
The Complete Hammer

Machine with Guards
Inside view with the large pulley / flywheel and guarding.
Main column, filled with steel shot.

Spring pivot made from a hydraulic cylinder rear pivot and mount. Cheap, precision, has the clamp for the spring, made the top plate and drilled a spring seat bolt hole to locate the spring. also grease holes from the fitting to the wear points
The pitman arm pivot at the spring end. Again cylinder parts, again the pivot is drilled for a locater pin, and the pivot pin is grease fitting and drilled to the wear areas. Right, the ram rollers with grease fittings.
The crank to pitman. Pivot is a shoulder bolt, with a grease fitting on the pivot. The second image is the crank with pulley and bearings. Note that guard is hinged to swing away for service
The Dies
The Dies
Stroke Adjustment
Grease Fitting Access in guard.
Crank and Drive wheel
Large pulley / flywheel and crank uncovered.

SPECS:At present

Ram is 32#
Crank stroke is 7", stroke of the ram at full speed is about 11"
Dies are S-7 combination type.
Motor was a found, without nameplate, 220vac 1 ph, and i suspect is in the 3/4 to 1 Hp. range.
The photo entitled stroke adjustment is the access to the grease fittings thru the guard.

I put grease fittings to feed moly grease to all moving surfaces, and have not seen any wear yet.
I am in the process of reworking a bit. I went from a 1" radius on the fullering portion of the dies to a 7/8" radius per Uri Hoffi's design, and have changed to a heavier, tapered truck spring. I am adding about 12# to the ram.

FredlyFX, the hammer beats a hand hammer every day. I am tuning now for max. performance. As I am a pretty good scrounger, i have about $43.00 invested in the hammer, and about that much more in the foundation.

To all who have or are going to build a JYH, especially one of the crank actuated spring hammers, Please, Please install a guard on the machine top to contain the ram and spring parts if the spring breaks. The ram will exit the machine if the spring breaks on the upstroke! I have seen several JYH's with unguarded belts, cranks and springs. Please don't run this way, as the risks are too high.

I will advise as to the effects of the changes.
Copyright © 2004 by Jock Dempsey, DEMPSEY'S FORGE