Not exactly an elegant solution but it works. Sometimes a simple but crude solution works just fine and doesn't need to be "attractive". I needed some way to hold the crankshaft while I adjusted the stroke and was able to knock this out in a couple of hours from materials I had on hand. If I had it to do over again I would make the dovetails on the tool taller to take up more space in the crankshaft dovetails...but this one works.
I tend to excessively oil and grease my equipment...just built that way I guess. On a couple of occasions I over greased the crankshaft which caused it to sling grease out from behind the crankpin. It covered me and my shop in grease blobs. I know I'll do it again so I made a fender or shield to prevent the grease from being slung out on me and anyone else in the shop.
Making a tool to adjust the stroke
3 Phase wiring at the motor.
The controller wired to the motor.
I rough machined a blank die from S7 tool steel and sent it to Steve for a fit check. It mounts centered and at the right height with a 1 degree taper wedge to secure it to the 10 degree dovetails in the anvil. I will finish it and others to the same dimensions, have them heat treated, and polish them.
5/8 inch by 7 inch wedge anchors were used along with some anchor epoxy.
I made a tool to hold the crankshaft while loosening and tightening the crank pin nut in order to adjust the hammer stroke.
Steve has finished my hammer. Both sides are running very well and it has been painted. I'll make arrangements to drive up to Steve's shop with a trailer and bring in back to my shop in the next couple of weeks.
Now I just need to cut off the anchors flush with the nut.
The lower anvil is placed and bolted into the lower arm of the Pettingell style hammer side. This holds the lower die in the anvil's 10 degree dovetail.
Three phase wiring in process.
Each corner received a 1/2 inch block with a hole for the 5/8 inch anchor.
The base of the Powell hammer is a solid steel plate and must rest on a flat surface to keep the hammer from "dancing" across the floor when using it. My shop floor is not flat nor level so I blocked the corners and leveled the machine with shims. Then I inserted 5/8 inch anchors and used some anchor epoxy to ensure the anchors hold. The hammer stays put now and runs smoothly.
Shims were used to level the hammer. The shims also have holes for the anchor,
Pettingell style upper arm in fabrication. Size increased from 3 inches to 4 inches to strengthen the arm as both the Yoder style side and the Pettingell style sides have long arms.
Baldor motor on the Pettingell side.
Clutch cone being machined.
Wiring up the motors on the hammer. I'm using a Siemens motor controller with integrated on/off switches on each motor and Baldor Industrial grade, 2 HP, 900 RPM motors. I ran conduit between the motor controller and the motors on both sides and wired the controller with 10 gage wire to the motor. I will run 3 phase 240 volt power to the controllers next.
The slide (piston) and the anvil align ensuring the dies will strike each other at the sweet spot. The Baldor 2HP, 900 RPM motor is installed.
A view looking at the Yoder style end. The pedestal is designed to allow it to be filled with sand to add weight and dampen vibrations if desired.
3/4 inch conduit had to be run up the wall on over the celling to provide a drop to the hammer.
Powell Hammer Constructed in Steve Powell's Shop
Shaping to a buck
I made up 1/2 inch steel blocks for each corner and some different thickness shims for leveling.
2 junction boxes were attached to the celling to provide a box for each motor
The upper slide (piston) mounts in a dovetail and reciprocates through a crank pin driven by the motor and a connecting rod attached to a spring system which emulates hammer blows.
Finally, the hammer in my shop. Now I need to position it and level it. Then hook up the 3 phase power and start working on it!
Wiring up the 3 phase power to the Powell Hammer. My shop doesn't have commercial 3 phase, so I use an American Rotary phase converter that is wired to a load center. I used a 30 amp breaker in the load center and ran conduit up the wall to the ceiling and over to the hammer. I used 2 junction boxes on the celling so that I could drop 2 lines down to the hammer...one for each motor. I then wired the 3 phase supply to the motor controllers and turned on the hammer. It runs smooth and strong. Only thing left to do is block and anchor the hammer to the floor then make some more dies.
The Pettingell style side ram and action has been installed and also aligns perfectly. The hammer runs very smoothly.
At Steve's shop picking up the hammer. Steve with the hammer and Steve on the trailer helping set it up for the trip, and the hammer on the trailer.
Installing a grease fender
The Yoder style side ram and action has been installed and aligns perfectly. The rear clutch pivot is offset like the original Yoder hammer. Steve's attention to detail is outstanding.
American Rotary phase converter and load center.
The slides (pistons) for the Yoder side on the left and the Pettingell side on the right. It's evident here that the Yoder style has more mass and should be able to hit harder.
Fabrication of the hydraulic foot controls has been started. Steve places the heel mount (not installed in this photo) for either left or right foot preference according to the desire of the customer. Right foot for me.
Motor and clutch fitted to head.
Normally when shaping to a buck, the item being shaped is no larger than a door skin or a fender. A friend who owns an industrial fiberglass company needed to make a mold to form a fiberglass door skin for an Airstream trailer. We are shown here shaping a 6'3" long door skin out of 18 gage cold roll steel sheet that will be the base of the mold. The buck that we used and the skin during the process is also shown. This is the largest piece of metal I have ever shaped in the Powell hammer. We both shaped and planished the skin with the hammer. I find that I learn something every time I turn on the hammer. Still trying to develop skills.
Head is squared and positioned
Steve acquired a Fosdick and Holloway radial arm drill, converted it to VFD drive, and mounted for effective, straight drilling and tapping the column and base.
Baldor industrial 2 HP, 900 RPM motors used.
Installed a set of shrink dies that I fabricated into the Yoder style side. I primarily use the Yoder style side for shrinking and the Pettingell style side for shaping and planishing.
Conduit run between the motor controller and the motor.
Siemens motor controller with start/stop buttons.
Connecting the 10 gage power supply lines to the 30 amp breaker in the load center.
The 3 phase power supply lines were connected to the magnetic starter poles on the motor controller.
Steve Powell custom built a long arm, double headed power hammer with a Yoder style head on one side and a Pettingell style on the other side patterned after Red Tweit's "Yoder-gell". It was completed in September 2017 and moved into the shop.
The crankshaft in the Powell Hammer has two cap screws, one at each end of the dovetail to prevent the connecting rod from being thrown out of the crankshaft if the crank pin nut were to become loose. Most hammers don't have this safety feature but should. Hammers have "thrown a rod" during operation over the years and Steve came up with a very simple way to prevent damage in the event this occurs. However, it creates a problem in making a simple tool to hold the crank while wrenching the nut. I cut some 60 degree dovetails to match the dovetail in the crankshaft and welded them to a pice of bar stock cut to form a wrench.
Using 900 RPM Baldor 2HP motors on both sides....Yoder style side shown here.
Flexible 10 gage wire was used to connect the hammer to the celling mounted junction boxes to prevent vibrations from being transmitted to the conduit.
Both sets of arms are now mounted on the pedestal. The Yoder style is on the left and the Pettingell on the right. Steve designed the pedestal to have both sets of arms and the hammer anvils at approximately the same height.
The upper slide (piston) shown on the upper arm meeting the lower anvil. The upper slide holds the upper die and reciprocates emulating the hammer blows of a metal worker.
Front view of the upper arm dovetail for the slide and the lower anvil.
Baldor motor on the Yoder side.
Yoder style head and arms starting to be fitted to the column. The column is designed to have the anvils on both sides at the same height and the dies are interchangeable between sides.
Copyright © Jack Pledger