Peter Dodd

My stroke adjuster is almost all the way out,the thrust washer is still all on the crankplate.runs much better at this setting than on shorter stroke.All mechanical hammers will have a range where they cycle well,on mine with the heavyst springs I can fit in without coilbinding and at 240bpm it cycles real well.

Patent is in the historic section(controled atmosphere in old mine or some such)in Cwmfelinfach South Wales.5 digit British pats are pre 1914.Taken out by William Jarvis & Smith Murgatroyd,two and half pages text & drawings.Mostly about the toggle arms having Tee sections.This is on the smaller hammers of this type.The bigger ones have pins and bushes.I spent a bit of time & effort making shure all the pivot points work correctly,bushes tight fit into holes,pins free to rotate in bushes but with small keep plates in milled slots to prevent pins rotating.All adds up to better machine life and excelent mch controll.Also use bottle jack & hard stops to cut down on free play in the linckage.Hammer sits on approx 6 inches orregon beams cross bolted together(mate has horrizontal forging mch which headed up 7/8 bars of correct length.) That all sits on about 2 cubic meters concrete as base isolation from shed. The bigger the mass off foundation the more efficent the mch.Article I read in ABANA paper some time before I got my mch going stessed the importance of setting the clutch to just start driving then have the brake release.

No pics on PC yet,camera got broken.Will post some asap .Rebuilt my hammer and partial rebuilds on various friends hammers over several years,made 4 or 5 sets of spare springs for Herculees from old rail wagon springs(high vibration/dutycycle material),had 2 sets made by comercial spring maker bbut both sets broke when mates were working material too cold,rail springs perfect and easy to work with gas torch.

I have one of these hammers fully rebuilt,improved brake shoe assembly(old one was mangled).Made new lower arms-forged 4140 then machined.New springs.Severn half hp & 240 bpm flat out,hits real hard with exelent control.Single blow or multiple.Patent taken out in 1910-got a copy from England for about one pound seventy pence.Arms on mine hang down a little.cycles real well,nothing binds up-spent much time getting thatall just so.any faster or more weight on mine and things would bind up/break.