roy_tate Posted October 20, 2009 Share Posted October 20, 2009 I just bought a working Kerrihard mechanical hammer. It looks like an older 30 lb model. It needs a slightly smaller pulley on the motor shaft, and perhaps a few older bolts replaced. The guy painted it red before tail-gating it, and the upper die is welded in. It has an expanded metal safety cage for the spring mechanism. Has anyone found any resources on the web for this model? Someone at the 2009 Saltfork Conference recommended that I ask Sid Suedmeier. I figured I would ask here, and educate myself some. Does anyone have any pictures that you could post on IForgeIron? I guess I'm most interested in a picture of the upper and lower dies, and particularly some measurements of original die sizes. I tried searching the Galleries to no avail. I will add a few photos to my gallery and add a comment with links soon. Quote Link to comment Share on other sites More sharing options...
AndrewOC Posted October 20, 2009 Share Posted October 20, 2009 Hi Roy, In 'Pounding out the Profits' Douglas Freund has nearly 5 pages on Kerrihard hammers and the company of the same name. Throughout the rest of the book Kerrihard's frequently rate a mention in comparison with other mechanical hammers. I very much value Freund's book for its history, illustrations and development aspects; however it isn't much of a technical book. I would expect to get more of that from this forum and other recognised experts like Sid. In my limited experiance you can make whatever bottom block fits and is sensible. For the top clearing moving parts and not going overboard on weight would be my first considerations. I must admit not knowing exactly what 'over-weight' allowance can be put on the tup of any hammer- i'd stay reasonably close to the rating (or in my case- guessed rating). Looking at the illustrations might give you some idea of the die size in preportion to other parts of the hammer; you are lucky you have pictures- for mine (with obligatory worn blocks) has no pics...yet. By the looks of Douglas' pics the blocks are twice as high as the width between the dovetails (approx of course). Eventually you will find someone with the least worn out example of your machine to copy specs from. Great to hear of a spring hammer that isn't an LG ... maybe a virtual hammer-off in the future?? Have fun, Andrew OC Quote Link to comment Share on other sites More sharing options...
anvillain Posted October 20, 2009 Share Posted October 20, 2009 Roy I have a Kerrihard 30 lb hammer. A friend of mine knew which junkyard his uncle's machine ended up in, so I went to inquire about it. This was about ten years ago that all this happened. I got it for less than scrap price. It was lying on its side in the mud but mostly unharmed except for the large crank bushing was so loose it had nearly a quarter inch of slack in it. Still in its sorry condition after cleaning up and putting an electric motor on it, it would hammer. But it was so loose I could not tolerate it so I rebuilt the crank and put a new bronze bushing in it. (It originally had no bushing, I believe, but I used the bushing to help make up for the lost material) After a little TLC it does a respectable amount of work. I will try to get some pics posted. Mine just has drawing dies that were mostly used for sharpening plowshares back in the day of moldboard plows. But it is very versatile in that it doesn't care if its hammering a plowshare or drawing out some tool edges or making tapers etc. I also know of a Kerrihard of the larger size which I believe is a 55 lb hammer. It is at a historic blacksmith shop. I love the mechanical design of it which allows a very small power source to operate that hammer. I you study the mechanism you will notice that the upstroke is slower and has more torque, but the downstroke, because of the geometry of the linkage is really quick which gives a lot of punch from such a simple machine. In my opinion those engineers really created a jewel of simplicity. Also the clutch will last indefinitely. It is a free wheeling wide pulley(made for flat wide belts from an overhead line shaft). However I just run mine on a single v-belt,3/4HP elec motor.There is adjustable clearance between a cast iron face plate and the pulley. When you step on the pedal a cam squeezes the two together and engages power to the crankshaft. I fear that whoever welded the dies together did you no favor. I would guess it has not been used since the welding was done or the weld would be broken. There are probably many of these machines around, I've seen several in my limited travels in the blacksmithing world. I removed my dies during cleaning and for curiosity. IIRC they were locked in with thin wedges. Anvillain Quote Link to comment Share on other sites More sharing options...
Dave Hammer Posted October 20, 2009 Share Posted October 20, 2009 I bought a Kerrihard a couple years ago. Cute little machine. Neat design. The ram guide was broken, so I had to repair it. It had (what appeared to be) original dies (at least the shape) on it. They proved (to me) to be totally useless for the type of forging I do with a power hammer. The profiles of the top and bottom die were different (probably very effective for shaping farm implements, but not for drawing out or using tooling). I didn't keep original measurements, but I milled the dies into combination dies that work reasonably well. I can also use tooling with the hammer now. The working surfaces of the dies ended up to be about 1.5 by 3.5 inches. If I were to do it over, I would probably just make them flat dies with a small radius on the sides. Quote Link to comment Share on other sites More sharing options...
peacock Posted October 21, 2009 Share Posted October 21, 2009 call Sid at little Giant. He has several Kerrihards and likes them He will be glad to talk to you. Phil Quote Link to comment Share on other sites More sharing options...
roy_tate Posted October 21, 2009 Author Share Posted October 21, 2009 I'll post some photos here when the gallery is fixed, but for now, here is an album from Picassa ... Picasa Album - Roy Tate - Kerrihard Power Hammer. Someone at the 2009 Saltfork Conference suggested that the welds would break soon enough if I just used the hammer hard enough. I will be sure to inspect and lubricate the hammer before each working session. Thanks for everyone's input on the Kerrihard. I'll try to post some useful information in this thread as I learn. Quote Link to comment Share on other sites More sharing options...
Bentiron1946 Posted October 21, 2009 Share Posted October 21, 2009 I think that instead of "hitting it hard enough" to break the welds I would grind them as thin as possible first, you might just take more original material then you want when you "hit it hard enough". Quote Link to comment Share on other sites More sharing options...
AndrewOC Posted October 24, 2009 Share Posted October 24, 2009 (edited) Roy, You never know with old welds. Cast iron/steel isn't the easiest stuff to weld but it may have been done well; looks like plenty of weld beads there any way. May last forever or already be broken- like you say regular inspection. good luck and enjoy. Andrew OC fellow broken-welded-hammer owner Edited October 24, 2009 by AndrewOC more blah Quote Link to comment Share on other sites More sharing options...
arftist Posted October 24, 2009 Share Posted October 24, 2009 Are you sure it is running too fast? What are you bsaing that on? Hammers that small run much faster than large hammers. Quote Link to comment Share on other sites More sharing options...
roy_tate Posted October 25, 2009 Author Share Posted October 25, 2009 Arftist, I'm basing it on the previous owner's advise. The flywheel says 250 RPM, so I'll find out soon. You guys might not believe it, but I don't have any electricity in my shop yet, so I haven't been able to play with it. I'm trying to be patient. :mad: Quote Link to comment Share on other sites More sharing options...
Ten Hammers Posted October 25, 2009 Share Posted October 25, 2009 Attached is a pic of my Kerrihard. It belonged to my mentor, Gilmour Barbour. When I recieved the hammer, it ran on an old 3/4 horse 1725 motor. I replaced that motor with a Dayton 1 1/2 hp ( tefc). I also built a jackshaft (barely visible in the pic). From the power source, the pullies are: 2" to (choice of 5 or 6" on jackshaft). Other end of jackshaft = 4" up to the 10 on the hammer. This gives me around 345-360 for speed which works well for me. The hammer would not run in cold conditions with the old motor. OK, the system will not let me post pics now. Will try that later. Quote Link to comment Share on other sites More sharing options...
Ten Hammers Posted October 26, 2009 Share Posted October 26, 2009 (edited) Ok maybe the pic will load this time. The hammer sets on a piece of bridge plank. Edited October 26, 2009 by Ten Hammers Quote Link to comment Share on other sites More sharing options...
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