Looking for Fairbanks hammer operating manual...

Thanks Justin.

Have you run into talk about oiling the brake? I know there is a drip hole for the brake cam lever, but I got the idea somewhere the drum/shoes are supposed to be oiled

Mike
 
here's my final jackshaft setup, with 2 ~25lb flywheels, it picks up instantly now, and it's even easy to get single blows even without the brake at all.

I dont think you want to oil the brake, just like you dont want oil on the brakes on your car. What you are probably thinking of is the clutch blocks in LG style power hammers, which need to be oiled so that they have more slip, for treadle control.

jackshaftfinal.jpg
 
I know the feeling about not oiling brakes. Why I asked is that feeling fighting what I can't remember the location of. Seems like it was "official"... like in the Fairbanks manual, but maybe some other "official"... specific to Fairbanks, for sure. Maybe it's just me reading a thing wrongly... t's a thing that has happened before. I'll keep digging, Justin, and if I find the reference, I'll holler at you.

Do you have numbers for how much "out" your hammer guides are now? Or, like how much you are going to mill off the cover plate? Do you have numbers for what clearance you'd be looking for at end of job, w/ shims in?

Mike

Edit: Just thought of a thing... hammer hung on pitman hung on "whatchamacallit" and if the guides are tight and either of the two connections are off line with the plus/minus of hammer to guides, there is going to be a bind that is not coming from "too tight hammer guides". You have ideas about how a person would go about finding that out, Justin?
 
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So, interesting thing about my "75 lb" power hammer...

Turns out that i think more of the slop in the head is due to wear in the link arms than in the ram guides. Putting a new spring in it while I have it all apart like this as well. I was told by another fairbanks owner that a 'old' style 50lb Little giant spring is just about the exact size needed. My old spring wasn't 'right' for the hammer either, was a much longer, lighter weight spring under really high compression, though it worked just fine for the last 20 years. Will throw it in my parts bin and use the LG spring I just ordered which is a good bit beefier, and probably better suited to the 110lb ram head anyways.

Even though I just got the hammer up and running, I may leave it 'offline' and just use my forging press during the winter, and re-machine the holes and bush them with bronze to eliminate the slop and whatnot. or even fabricate entierly new toggle links that are adjustable like the ones outlined in the Richard Kern Little Giant book. Cant hurt to make some improvements "while i'm in there"

ram.jpg
 
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Justin,

If I'm remembering right, original to Fairbanks was hard pins. When I had the arms re-bushed (by 45 year tool and die maker friend) He wanted to bush the arms hard and run soft pins. His experience feels the soft pins wear and the bushings don't... replace the pins down the road instead of the goat-screw of figuring hole centers and distances and trying to hold the pieces on a milling table to re-bush. You need to know, neither of us is a hammer person and only one of us has hard time in the metal world. Do you know how Sid and Keri approach rebuilding these parts?

I know Sid told me NOT to build the pins for non-rotation (Fairbanks standard... at least in the later ones like ours... mid 1930's). Are your pins built to not turn?

I'm wondering... not telling, I promise... The way Sid lined me out on adjusting the hammer guide, I'm not seeing a way for the hammer guide to be tight and have the hammer do anything but follow the guide. I can see how loose arm links might throw the hammer against the guide and cause excessive wear, though. Am I misunderstanding what your are saying and/or not clear on things to your understandings here, Justin?

Mike
 
So I replaced the spring on the hammer with a new spring from a 50lb little giant (old style, a pretty close to perfect fit). The old spring was so worn out that every setting on the hammer was choked up as much as it could be.

For a gauge of how choked up it was, without changing any of the setting, with the new spring and a whole lot more tension, it would not even strike a 2x4 when running. I loosened up and adjusted the pitman arm in both location and played with it to get a good blow.

After I had it working well I was using it to draw out a bar when .. THUD, hammer goes down... and doesn't come back up. The pitman arm had snapped!
pitman.jpg

pitmanarm.jpg


Turns out that this was probably the second time that the pitman arm had broken. The arm is 15/16 in diameter, but had been drilled and tapped for 3/4" had a 3/4" set screw run through it, and was cross drilled and pinned. A new t-nut was made and then threaded onto the set screw, and then also pinned so it couldnt come un-screwed. This is a rather 'janky' fix IMO but it's worked for some time. Looking at this cobbled together mess of broken parts, I saw a much much easier way to repair it all.

15/16 is not a standard nut and bolt size so I debated boring the large bronze bearing out to 1 inch, but decidded against it because if I'm going to do that work, I'd rather re-make the whole bearing, hone the pitman pivot and get it all slop-free... but a piece of bronze large enough to remake the whole bearing is about 75$. Obviouisly 3/4 is still plenty strong, and a 3/4 ID 15/16 OD bronze sleeve bearing is a standard available size, so instead of replacing the broken 3/4 set-screw and putting it back together, I'm making a much simpler solution. I got myself a long grade 8 bolt, have ordered sleeve bushings, and have just finished making myself a new T nut for the adjustable pitman-wedge.

Originally I was just going to use the same repaired pitman arm, and had prepped it as follows
pitmanfix.jpg


But since I found sleeve bearings of the right size, I'm just going to use one solid grade 8 bolt for everything, with sleeve bearings inside to fit the big bronze bearing that goes in the pivot.

pitmanfix3.jpg

pitmanfix4.jpg
 
Dupont Fairbanks hammer back up and running better than ever. Put
the new pitman arm on the hammer today after work. Works better than
ever now, can get slower lighter hits up to fast real hard blows by
varying treadle pressure now, which before I replaced the spring was not
very doable. Glad that the pitman arm broke just a day after replacing
the spring so that I could get it fixed before I really need it for
something, rather than in the middle of a project.

Fix is mostly invisible once installed except for the modern grade 8 nut, washer, and spring washer on the front.
pitmanfinal2.jpg

pitmanfinal.jpg



Also here's a real poorly lighted and out of focus vid testing the new pitman arm on a 2x4 =P
This thing packs twice as much punch as it did before, and even though
the hammer is SUPPOSED to be 75#, as I showed before when I measured
the ram with top die, it's 110.0 lbs on the button, so plenty of hammer
for me to get lots of work done with!

https://www.youtube.com/watch?v=RPhiiN6qSr8

Fixing up the pitman arm got rid of a lot of the slop in the hammer too, as
the inside of the big bronze bearing in the pitman was worn a good bit,
but pressing in the new bearings and using the 3/4 bolt took much of
that slop out. The only 'major' project left on the hammer is to repair the broken existing, or make a new, brake ring.

Right now the hammer is running off of a 5HP rotary phase converter (the
first motor I turn on before I flick the switch on the hammer) I'm
thinking about putting it on a 3HP VFD (KBAC29 or the like, which will
run off of single phase and give me 3HP 3PH)
I think the fastest it'll go is a little fast right now. Manual says
to set it for 350 bpm, it's closer to 385 currently. I think I should
probably slow it down to between 325 and 300, which is ratings for the C
and D size (100 and 125 ram weight)
 
Nice work, Justin. It would take me a month to get that figured and done.

How do you get your spring out and in?

Mike
 
I used a pipe vise (one of the ones you make out of a pipe) to compress the spring then knock a pin out of one of the arms, then release tension. then I put the new spring between and compressed it with the pipe vise untill i was able to drive the pin back through the arm.
 
I used a pipe vise (one of the ones you make out of a pipe) to compress the spring then knock a pin out of one of the arms, then release tension. then I put the new spring between and compressed it with the pipe vise untill i was able to drive the pin back through the arm.

I'm not getting what you mean, Justin.

Mike
 
I used a big clamp, my largest C clamp wasnt large enough so i used a pipe vise clamp, and put it across the toggle arms at the spring so I could compress the spring, with the spring compressed I could drive out a pin on one toggle arm to the ram.

Then i could release the tension on the spring and replace it, and then work in reverse to get it all back together.
 
I know the feeling about not oiling brakes. Why I asked is that feeling fighting what I can't remember the location of. Seems like it was "official"... like in the Fairbanks manual, but maybe some other "official"... specific to Fairbanks, for sure. Maybe it's just me reading a thing wrongly... t's a thing that has happened before. I'll keep digging, Justin, and if I find the reference, I'll holler at you.

Don't know if you are still out there, Justin. Did get figured about oiling the brake ring. The Manual does say to, but I've looked for the hole(s) for years and never seen them... until today. Was working on brake ring due to bad drag in rotation not found a solution to anywhere else. Got everything WD-40-ed up, wedged the brake ring part way out of the drive pulley cum brake drum and from the "shoe side of the brake ring there were two holes a few inches either side of the brake ring pivot pin. Holes 1/2 inch-ish long and filled solid with scale and oil (this hammer has been in business 84 years now). I had to chisel down from the top nearly a 1/4 inch to reach metal and the other end of the hole on the inside of the brake ring. No wonder it was hard to see. "Betty spins like crazy now the gick in the braking system is gone.

I'm guessing the tolerance is so tight between drum face and brake ring shoe-face having lub in there to keep scale dust washed out is a good thing.

If you don't (didn't) find oil holes in your broken brake ring, I'd guess it as a re-design from later years... like the adjustable hammer guide. Which, by the way, causes me to wonder... how your face plate machining/shimming solution worked out?

Mike
 
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