arftist Posted January 13, 2010 Share Posted January 13, 2010 Grant is definitely correct about this, surprised I didn't see it. There is a table of blows per minute versus hammer weight on the Little Giant web page. By the way Grant, fasinating factiod on the pendulum. Quote Link to comment Share on other sites More sharing options...
monstermetal Posted January 13, 2010 Share Posted January 13, 2010 Another thing that comes into play here is what's known as the "natural period of oscillation”. Mechanical systems of weights and spring all have their own unique "natural period of oscillation”. This is a speed at which they are “happy” and use the least power while delivering the most work. You'll notice that most hammers run at a similar speed to other hammers of similar size. For a given weight there is fairly narrow band of maximum speed they operate at. The design of the spring system and the stroke have only small effects on this. A good example of "natural period of oscillation” is a pendulum. For a given weight and length of arm there is only one "natural period of oscillation”. Interesting fact: Regardless of the length of swing, a pendulum takes exactly the same time to make a stroke! If it's making a big swing it travels faster, if it's making a short swing it travels slower. In either case it will do exactly the same swings per minute. Anyway, because of the above, trying to push a system 20% faster could easily take 50% more power! And there you go... Grant knows stuff... Quote Link to comment Share on other sites More sharing options...
patrick Posted January 13, 2010 Share Posted January 13, 2010 Michael, I'm surprised you're having trouble with that motor and would have to agree that something else in your system is probably the cause of your problems. My hammer, though tagged as a 300 lb machine has an actual ram weight of 460#. The drive pully on the hammer is 26", just like yours. The drive pully on my jackshaft is 8" and I am using a belt that is 8" wide. The motor is a 10 hp, 1800 rpm single phase unit. I haven't had any problems with my set up, though I've never checked it with an ampmeter while it was running. As far as rpm of the hammer is concerned, you should be able to run that hammer at 225 without any problems. I run my around 200 and I've seen another large Bradley set up to run quite a bit faster than that. Somewhere I got the idea that the pulleys mounted on the motors supplied by Bradley were 6" OD but I can't find that reference now. Patrick Quote Link to comment Share on other sites More sharing options...
Dillon Sculpture Posted January 13, 2010 Author Share Posted January 13, 2010 All right, I would like to try the 5" pulley but is there any suppliers? I looked on Thomas, modern equipment is all I could find. I hate to modify the one I have, anybody have a source for leather pulleys? 5" diameter 9" long 1 7/8" shaft with a 1/2" key Quote Link to comment Share on other sites More sharing options...
monstermetal Posted January 13, 2010 Share Posted January 13, 2010 All right, I would like to try the 5" pulley but is there any suppliers? I looked on Thomas, modern equipment is all I could find. I hate to modify the one I have, anybody have a source for leather pulleys? 5" diameter 9" long 1 7/8" shaft with a 1/2" key I might be able to come up with a flat belt pulley... Let me do some checking.... You have a 8" wide belt? Quote Link to comment Share on other sites More sharing options...
Dillon Sculpture Posted January 13, 2010 Author Share Posted January 13, 2010 Thanks Larry, 5" diameter 9" long, 1 7/8" bore and a 1/2" keyway. This is a leather pulley, stacks of leather donuts riveted together through the ends of the pulley. Patrick, The pulley is a 6 1/2" same as in the literature, hammer speed of 150 to 175. Odd thing is they list your hammer with the same pulleys, same motor speed but a higher hammer speed 175 to 190. I wonder who was writing this stuff? My friend has the 200 we bought and it has a 6" motor 22" hammer pulley and they list it at 225 hammer speed, go figure. WOW! 460 lb. ram, I am going to have to weigh this one of mine, any guesses, maybe 650? I have a 4 1/2" x 6" billet of chromoly I would like to get tested, PM the address? Also what do you think about turning the dies 90 to the dovetail? I am thinking 10" top and 12" bottom total width of the dovetail is 4 1/2". Michael Quote Link to comment Share on other sites More sharing options...
Nakedanvil - Grant Sarver Posted January 13, 2010 Share Posted January 13, 2010 Not 100% certain, think it's rawhide not leather. Should have asked before, which type of Bradley are we talking about? Beam, Guided helve, Strap hammer or Compact? The first three do run pretty fast by most standards. Might want to go with 5-1/2 on that pulley. Quote Link to comment Share on other sites More sharing options...
Dillon Sculpture Posted January 14, 2010 Author Share Posted January 14, 2010 Thanks again Grant, Any chance you can catch the Niles posting before it falls of the page? I'm getting ready to tear down an would like to make the adjustments before reinstalling. Quote Link to comment Share on other sites More sharing options...
patrick Posted January 14, 2010 Share Posted January 14, 2010 Michael, I know of another "300#" Bradley like mine that has a 460# ram. I have a spare ram for my hammer that weighs 325#, so either my hammer has the ram used on the 500# machine, or there was an option to buy "heavy duty" hammer or the company changed the design over time. The hammer I have was built in 1944, the other one I referred to was a 1926 machine. I'll send you a PM shortly with my mailing address. Grant- The hammers we're talking about are the Guided Helve type. Patrick Quote Link to comment Share on other sites More sharing options...
Nakedanvil - Grant Sarver Posted January 14, 2010 Share Posted January 14, 2010 Adjustments? What adjustments? Oo, oo! Can't you just turn the old pulley down? Quote Link to comment Share on other sites More sharing options...
patrick Posted January 14, 2010 Share Posted January 14, 2010 Michael, I forgot to comment on your question about making new dies to allow you to work from the front of the hammer. There should be no problem with this approach, but you will be limited by the spacing between the guides, i.e. the to die can't be any longer than the distance between the guides. That is still a pretty good distance on this hammer, but you could actully make a longer die if you kept the orientation as it is. This is how Bradleys were designed to be used and they had such big guides because the expected users to make up specilty dies in which there were a lot of off-center blows. Typical applications would be the forging of breaker bits. A dedicated die for this type of product might have 3 different components-A taper, and edger and a trimmer. To get all of that in one die, you had to orient the dies in line with the length of the hammer. In your case, where I presume flat dies are the primary tool, this may not be as important, but a big flat die does provide a lot of options. If you do choose to change the orientation of the dies, I'd suggest machining the new ones so that the dovetail is slightly short. This will let the top of the sow block support the majority of the die area. Patrick Quote Link to comment Share on other sites More sharing options...
Nakedanvil - Grant Sarver Posted January 14, 2010 Share Posted January 14, 2010 Good advice Patrick. Think you nailed it. Quote Link to comment Share on other sites More sharing options...
arftist Posted January 15, 2010 Share Posted January 15, 2010 If you don't want to turn down your existing pulley you could turn one from aluminum quick enough. Quote Link to comment Share on other sites More sharing options...
David Browne Posted January 15, 2010 Share Posted January 15, 2010 I was unable to locate a rawhide pulley for my hammer so I had an aluminum pully made for it. Seems to work fine, but i don't have anything to compare it to. I gotta think leather would take up quicker... Quote Link to comment Share on other sites More sharing options...
Dillon Sculpture Posted January 15, 2010 Author Share Posted January 15, 2010 I couldn't take more than a 1/2" before I hit the pins that hold it together. Most likely I will jackshaft this motor, I have a 16" sheave, pallet full of bearings, plenty of shaft material, and I know somebody that can weld decent. A 12" on the motor should put me at 160 and if it's not right it wont be hard to change. No 5" billet aluminum laying around, probably would have pounded it out by now. Patrick I bet you have the 500# ram on yours, my dillon scale measured mine at 460 yesterday but I don't know how accurate it is. It measured my weight 40 pounds light and my die billet was 60 pounds off, I'll try again with something different. I have a set of flat dies at 6" x 12" right now, great for tooling! The new ones would be primarily for fast drawing since they are a little narrow to begin with at 4 1/2" x 10". For some reason I just feel more comfortable in front of the machine, seem to have a better view as well. My hammer was built in 29 still has the original beam, I am considering replacing, any thoughts? Quote Link to comment Share on other sites More sharing options...
patrick Posted January 15, 2010 Share Posted January 15, 2010 Michael, Unless the beam in in really bad shape, just use it. The beam in my hammer is a used beam from the 1926 hammer I mentioned in an earlier post. When Steve Parker started at Clifford Jacobs on that hammer, he made them get a new beam, but they kept the old one and a spare. When I got my hammer, Clifford Jacobs had already sold their Bradley to Mark and Mindy Gardner, but for some reason had kept the beam that Steve took out and a spare so I ended up with both. Those two are both cut from a single block of what I think is maple. When I got my spare ram, I also got another beam which is laminated maple. If you are going to make a beam, I'd do it by laminating 5 or 6 layers of maple with the laminations running vertically. I don't think the one I have has bolts holding it together, just glue and maybe some wooden dowls, but I'd hesitate to drill any cross holes in a beam like this. If you're afraid the laminations will come apart, make some steel clamps. Patrick Quote Link to comment Share on other sites More sharing options...
JNewman Posted January 15, 2010 Share Posted January 15, 2010 Rather than a leather or aluminum pulley you could try a pulley made of hardwood, I have seen a lot of wooden lineshaft pulleys. Quote Link to comment Share on other sites More sharing options...
arftist Posted January 15, 2010 Share Posted January 15, 2010 I was unable to locate a rawhide pulley for my hammer so I had an aluminum pully made for it. Seems to work fine, but i don't have anything to compare it to. I gotta think leather would take up quicker... I bought a brand new cast iron flat belt pulley for my hammer, but it is only 4"x4". It has tiny grooves runing around it, about 1/64"x1/64". No problem with grip at at all. Quote Link to comment Share on other sites More sharing options...
Mainely,Bob Posted January 15, 2010 Share Posted January 15, 2010 One of the tricks the old timers used up here to improve performance of flat belts was to sprinkle a little diatom powder on the running belt.The same trick helps on a wood to metal clutch assembly. You can find diatom earth(powder)at most well stocked pool or spa supply stores. I like it better than that sticky goo they call belt dressing.May as well sell that to make fly paper with. Quote Link to comment Share on other sites More sharing options...
Dillon Sculpture Posted April 10, 2010 Author Share Posted April 10, 2010 Some things take longer than others... Finally got it done, I lost a little speed but the pull on the motor is significantly less, allowing me to use the full stroke without overloading the motor. While I was at it I raised the whole machine 3" which puts the bottom die at 36" off the floor. Quote Link to comment Share on other sites More sharing options...
monstermetal Posted April 10, 2010 Share Posted April 10, 2010 Some things take longer than others... Finally got it done, I lost a little speed but the pull on the motor is significantly less, allowing me to use the full stroke without overloading the motor. While I was at it I raised the whole machine 3" which puts the bottom die at 36" off the floor. Hey at least you got it done..... I cant count how many projects I have posted the "start" of and have never got back to finish.... Looks good. Quote Link to comment Share on other sites More sharing options...
jason0012 Posted April 12, 2010 Share Posted April 12, 2010 I had a lot of trouble with my 100# with the factory set up like that. It squeeled and squaled a lot, burned through several belts and had terrible pickup. I am used to the controls on a little giant so i set out making it run similar. Going from the little pulley to the big pulley you driven side has a tremendous mechanical disadvantage at starting. The contact area on the little pulley is quite small in comparison to the hammer pulley. I switched from a 3 1/2" pulley to a 14" and get good responsive single blows now. I also don't get the squeeling or burn through the belts. Now this did require redesigning the whole drive system, and of course adding an additional jackshaft. Now on the 100# hammer I have a 16 or 18" drive pully and the 14 was the closest I could find. I would have prefered an 18-24" but hey it works. Flat pulleys seem near impossible to find! Locating a match for a 26" could be problematic especialy 9" wide! Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted April 12, 2010 Share Posted April 12, 2010 A lot of the *old* farm machinery used fairly sizable flat belt pulleys. A good implement repair place probably has a boneyard that would surprise you! Quote Link to comment Share on other sites More sharing options...
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