Patrick Nowak Posted April 30, 2012 Share Posted April 30, 2012 Guys, I need to replace a part on my Bradley. For those that have Bradleys, especially the guided helve and strap types, you will recognize this as the hub that is keyed directly to the shaft. This hub froms the innermost of the adjustable excentric that controls the stroke. On one side of this part is a flange that has a circular slot that takes a square headed bolt. Three of these bolts pass through the outside eccentric. When the bolts are loose, the inner and outer eccentric rotate independantly allowing the stroke to be adjusted. When the correct position is reached, the bolts are tightened. The problem I have is that the slot in the flange is broken out for about half the circumferance and I can no longer get the hammer to keep a constant stroke. To fix this I have to tear out the entire shaft, and eccentric assmbly, get the hub off of the shaft and then procure a new hub. Does anyone know of a source for Bradley parts. I know that Cortland Machine was supporting them for quite a while but I'd heard they'd sold that buisness to Bruce Wallace. Does anyone know if either of these folks or others out there can supply the part I need? The originally is a cast iron part but I'd be just as happier or happier with steel. Patrick Quote Link to comment Share on other sites More sharing options...
peacock Posted April 30, 2012 Share Posted April 30, 2012 I made 1 for my 40 cushioned helve from steel. Mine only had 2 bolts 1 in the slot one on a clamp on outer rim. I might be able to make what you need, or maybe repair the one you have. Quote Link to comment Share on other sites More sharing options...
JNewman Posted April 30, 2012 Share Posted April 30, 2012 No source but you should be able to make a pattern and get one cast in steel. Do you have a picture of the part? I could give you some advise on making a pattern. Quote Link to comment Share on other sites More sharing options...
Dillon Sculpture Posted April 30, 2012 Share Posted April 30, 2012 Don't have a source, sorry. Sounds like you may have to build one, please keeps us posted. Is that a weak area in design? Quote Link to comment Share on other sites More sharing options...
jason0012 Posted May 2, 2012 Share Posted May 2, 2012 It shouldn't be too terribly hard to turn a new part out of steel. I have twisted the bolts off of mine a couple times but never seen one break. I think its more common for the strap to break, or get way out of round. I have had some trouble with that part on my hammer. Quote Link to comment Share on other sites More sharing options...
Patrick Nowak Posted May 5, 2012 Author Share Posted May 5, 2012 I was able to get a drop from a 12.5" diameter bar of 4340 from work this week and they even roughed out the hub. That and the original hub, shaft and the cylinder that fits around the journal of the hub were picked up by a local machine shop this afternoon. I'll have to follow up with them tomorrow to make sure they understand what I need. Conceptually it's not a difficult part, but it is big and there are some tight tolerances as you need an interferance fit on the shaft, the hole for the shaft is about 3/4" off center and its about 3" in diameter. The entire piece is 11" long and before drilling the 3" hole for the shaft it and machining in the T slot it weighs about 125#. I'm not sure if this part is a weak spot in the design of these hammers or not. My hammer was built in 1943 so it's not exactly a young machine, but by hammer standards it's not old either. I'm not sure what lead to the break out of the T slot. I know that similar damage can occure on milling machine tables from over tightening the bolts and I'm sure that happened here, but unlike a mill table were the T slot has no support, in the hammer part the T-slot flange mates up tight to the cylider that can be rotated to adjust the stroke so you should be able to really tighten things up without putting a bending force on the T slot flange. I've noticed that some the parts on this hammer do have casting flaws and that cracking has occurred in these areas. It wouldn't surprise me if that was the case with this component too. I suspect that every time the bolts loosened and the cylinder rotated while I was running the hammer, more and more of that flange was beaten away. The new steel part will have a flange 3/4" thick and being steel it won't be subject to the brittleness of cast iron. Quote Link to comment Share on other sites More sharing options...
Dillon Sculpture Posted May 5, 2012 Share Posted May 5, 2012 Glad your on the way to repair, pictures if you get a chance please. 12.5" bar would be their small drop eh :blink: Quote Link to comment Share on other sites More sharing options...
Kevin K Posted May 8, 2012 Share Posted May 8, 2012 Patrick, Is that hub clad w/babbitt? Are you talking about the same part shown in Welder Jim's picture in the tailgating section of the straight helve he sold- sitting on the hammer just to the left of the flywheel, with the sort of checkerboard pattern? Quote Link to comment Share on other sites More sharing options...
peacock Posted May 8, 2012 Share Posted May 8, 2012 Kevin, I think the part that he needs is the one that the shell you see in Jim's pic goes over. Quote Link to comment Share on other sites More sharing options...
Kevin K Posted May 8, 2012 Share Posted May 8, 2012 Thanks, I understand- should have read the post more carefully. Quote Link to comment Share on other sites More sharing options...
Patrick Nowak Posted July 8, 2012 Author Share Posted July 8, 2012 Well, I finally got the hammer back up and running. It took the machine shop about three weeks to make the new hub. It ended up being a shrink fit on the shaft and when I put it on, I botched the job. The hub shrank on the wrong place on the shaft. I tried to get the shaft out but even with our 2000 ton press at work we couldn't get it out without completly galling every thing up, so back to the machine shop it went. They were able to salvage the hub they'd made but had to make a new shaft. In the grand scheme of things, having a new shaft is a good thing. The orginal was bent on the drive wheel side and that resulted in a lot of push back on the treadle every time the shaft rotated. The new shaft has elimiated that issue. This time, the machine shop bored the hub just slightly bigger than the shaft and added 4 set screws to keep it from sliding back and forth on the shaft. It took me 3 afternoons to get the hammer re-assembled, but I did it and forged for about 6 hours on the July 4. The hammer is working fine, but that was a miserable day to forge. It was 102 F out side in the shade and I don't know how hot in the shop, but at work our shop has been pushing 120-130 most of the week. I sure am glad to have the hammer back. One thing I've learned is that even on the relatively small work I do with mokume, the big hammer with great control is essential for forging thin sections. While the hammer was down, I used three different shops to keep my regular work moving along (Thank you to MIke Garrett, Keane Pardiso and Doug Ponzio) and had a chance to run a 75 KG Stryker, 4B Nazel and 75 ton press. They all were good for what they were designed for, but none of them were quite as good at this job as the Bradley. I found the two air hammers to be harder to control than the Bradley, but that is probably because I'm not used to those machines AND they both require very slight changes in the treadle postion to accomplish rather dramatic differances in blow energy. The slack belt arrangement on the Bradley allows you to sneak up on your work more easily. The press was a challenge to use for thin work (0.210" forge thickness) because it sucks the heat out of the work so fast and because when you set a position, the electronic controller tell the press to complete its stroke to that position regardless of dwell time on the work. I ended up using a set of drawing dies with the press and that did work, but it took 2-3 times longer to flatten bars from 0.375x2.5 to .210x2.625 than it does with my hammer. I was a bit surprized by this becuase Doug uses that press daily to forge 5x5 and 6x6 cans of powder metal mosaic damascus. This just illustrates how much more power is required to deform a thin section than a thick section.The 4B had plenty of power, but for production drawing of 1x2 down to 0.75 octagons 2 ft long it felt slow. I think that hammer has a max speed of about 150 BPM and though effective, it was slower than I'm used to. In spite of my lack of familiarity with these tools I am still very grateful that all three guys allowed me to work in their shops to keep my own work moving to my customer in a timely fashion. Patrick Patrick Quote Link to comment Share on other sites More sharing options...
peacock Posted July 8, 2012 Share Posted July 8, 2012 I've said it before and I'll say it again. A good Bradley gives up nothing to an air hammer or any hammer for that matter. Glad you got your hammer back running I know I would miss mine. Quote Link to comment Share on other sites More sharing options...
nonjic Posted July 9, 2012 Share Posted July 9, 2012 Sounds like a nightmare with the shaft and wheel interferance fit :( Many moons ago a fitter we employed 'stuck' a 6' dia wheel on a shaft in the wrong place... we did not have a wheel press at the time so sub contracted the job of pressing it back off. They smashed the wheel. expensive and painfull lesson for me. We now have a horizontal 200 ton , specifically designed wheel press. You still need to be real carefull with it. On a small shaft (3" dia) 0.002" is a big pinch, and we are never shy with the (proper stuff) moly. The bradleys sound like great hammers, I hope to get some anvil time on one, one day! Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted July 9, 2012 Share Posted July 9, 2012 I think I'd have to spend some time forging on the Fourth if I had just got a big hammer going again even if I had to tie a bag of ice in front and back of myself! I was lucky? enough that my truck wouldn't start for a couple of hours that morning and I got a chance to do a bit of clean up in my shop, re-handled a favorite hammer and drug in a 12"x14"x6' creosoted mine timber in to get ready to cut to length and bury in the floor for the 515# anvil move planed for after the last part of the end wall gets officially sealed off. Then I hightailed it south to be there when my Mother had surgery the next day, so I could sit with my Father while my wife went to the hospital with my Mother. Quote Link to comment Share on other sites More sharing options...
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