C&P 7x11 Crank Shaft broken by movers

Your best bet is to have a straight shaft fabricated and forget treadling.

Daniel Morris
The Arm Letterpress
Brooklyn, NY

find a steel reseller - theres one in every city and see if the have stock material thats the same or close to yours (take a piece with you). if they don’t have the exact they should be able to lathe it down. just an idea.

We had a shaft break on our C&P 7x11 press. Here are a couple of things you can consider - both of which will need a competent machinist. The easiest process would be to remove the shaft from the press and remove the piece from the flywheel. Ask the machinist to center drill both pieces on the broken ends in preparation to fit it with an appropriate size and length pin. The machinist would then press fit the pin into one piece of the shaft, press fit the other piece of shaft onto the exposed portion of the pin, and then weld the joint where the two pieces fit together. Important here is to get the two pieces perfectly aligned so that when the flywheel is put back on it doesn’t wobble when it rotates. Another alternative (which was actually done for the shaft currently in our press) is to create a 7x11 shaft from a shaft out of an 8x12 press. The machinist would have to put the 8x12 shaft on a lathe and turn it to the measurements needed for a 7x11 shaft. In our particular case the machinist who did this was someone who worked on racecars and had the equipment and experience used in building engine crankshafts and other engine components. We then had to do some hand filing on the new shaft to fit it back into the press. Definitely more expensive than repairing the broken shaft.

John

Couple of comments.
A first glance it appears that the crankshaft was cracked already when it got hit and fractured the rest of the way. If that is the case then the flywheel was going to come off at some time in the future, when running. Without viewing the crankshaft in person I am not positive about the preexisting crack.

If this crankshaft is of a design that I think it is a new crankshaft can be built up from mild steel stock and machined to fit. It will not be original looking, but functional. I say this because I am not familiar with these presses.

There are two ways to approach this method. One is to take a length of shafting of right size, heat it and using a “Bulldozer” metal press shape the crankshaft throw to the desired dimensions and then finish machine on a crankshaft grinding machine. This would look closer to original. Doable but very expensive.

Other way is build up crankshaft out of bar stock and weld together, then do a final pass on bearing surfaces with a lathe.

My feeling is the torsional stresses on the center pin and outside welding method would lead to failure at some point. The only way to lessen that failure mode would be to put crankshaft in heat treat oven at 1200 degrees both before and after welding. Once again expensive.

Can you post more pictures of the crankshaft and give overall dimensions? Overall length, diameter, length of throw,etc. The more numbers the better.

Depending on how soon you need one made, and overall construction details and dimensions I should be able to make a new crankshaft for you.

Marshall

Just a note that the original shafts were spun cast steel, so will tend to have welding requirement closer to cast iron (pre-heating etc).

Making new is an interesting idea, but finding a shop with the appropriate capability for forging might be a serious challenge. A fabricated crank might work, but that too will require a very competent shop. Given the standard sizing of shafts (at least in the 8 x 12—-12 x 18 range) making fabricated shafts with treadle throws might be a worthwhile objective—though the shafts will probably cost well upwards of $300.

As it appears that it is a CRANKSHAFT and not a straight shaft replacement with a straight shaft/rod of any size wont solve the problem, would appear to be 2 choices, (possibly) recast/reforge>>>via Fort Knox??? or remove the CRANK via the oversize bearing housing as pictured, have the shaft (remains of) turned down, exactly the width of the bearing surface, (cast iron turns down well) have a STEEL extension sleeve turned and spiggoted onto the cast iron, turned down shaft, interference fit!!!the whole repair will automatically come within the confines of the bearing block , and its a pretty safe bet that, as the machine comes from another time/place, the piece of STEEL obtained will be standard imperial size, and will only need boring internally to whatever size the cast spigot is turned down to. There is the possibility that the fly wheel was keyed to the original shaft, which would involve cutting a key way, or you may be lucky enough, for the fly wheel to be anchored with a pinch bolt!!! And yes I have just performed this very operation for our local Industrial Museum, a machine was donated and busted on delivery, (exactly as posted) Not a printing machine but in essence exactly the same situation. Good Luck Mick

My sincere appreciation to all who have suggested possible repair avenues for the C&P crankshaft; I went back to look at the press again and to get more information/photos. I was so distraught upon initially finding the crankshaft busted a few days ago, that I missed seeing other major damage which I now suspect renders the press completely irreparable. Since I was not present when the storage company busted the press I cannot say how it actually happened, and neither can/will they, but to sustain the kind of damage the press evidences it must have been dropped from one heck of a height. Besides a snapped crankshaft/flywheel, the entire left arm of the press is also fully split/cracked completely apart in three places.(photos attached) Does anyone know the value of (what was) a fully operational, all-original construction, 1890’s, mint condition 7x11 C&P ? It seems that insurance coverage is in order; I am so grieved by this, it was a real beauty. Thank you.
Kind regards,
sandrsam

3cracks_arm.jpg

three additional cracks_arm.jpg

Other post discussing 7 x 11 OS presses have established that very, very few are still around. According to serial numbers, only 3318 were made. 8x 12s & 10x15s are going for $1000-2500 depending on where you find them. For insurance purposes you will need a qualified evaluation by someone considered an expert. Possibly a dealer like Letterpress Things or the sales group in Atlanta who post on this forum once in a while. So sad to see your press like it is.
-Mike

Thanks for the condolences Mike; I seriously cried when I found it like this. I will contact the folks you have mentioned. Kind regards, sandrasam

sandrasam, after you settle with the moving company what
happends to the press? james

Buy it back and part it out would be a sensible route in this environment !

I sold one last year C&P 7” x 11” for 1,700.00. It was perfcect.

Just make them pay for repairing it correctly at whatever the cost to them. They really don’t have to option of “totaling” it and paying you off unless you let them. Sure, it may cost more than the press is “worth” to fix it right, but it looks like it can and should be repaired — it’s not like there are breaks to the main frame, right, just the crankshaft and the roller arm? Don’t let them get away with anything less than either repairing as good as it was, or actually replacing with another 7x11 C&P.

to all:

We had the experience with a different kind of machine, not printing machine.

We had to “time” a sleeve-like piece (which was a cam) on a shaft, slightly tapered; the nut on the end tightened to lock the sleeve in place. Because the whole box-and-dice was constantly sprayed with oil, we thought nothing of leaving oil on several parts; but the sleeve constantly moved so that the timing became wrong. A friend, whom we thought did not have mechanical sense, pointed out to us that we should clean every trace of oil from where the interference-fit surfaces met, then assemble the machinery. That proved to be the right way, the very thin film of oil had been preventing a true interference fit. Not many places where this would happen in printing machinery, but useful to know,. if it happens.

Alan.

i bought a few machines when i was starting out, i had to take a package deal, the only thing i wanted was a paper cutter, a machinist friend of mine looked over the cutter and said it was ok, so i took the machines. the machinist didn’t know presses but thought one was a c&p, all three machines were $100 and they dropped them in my driveway for $15. how could i go wrong. The press had been dropped and i mean really dropped. There were steel plates bolted all over the frame, the platen was welded, i don’t think there was many parts that didn’t have some kind of repair, there was a line of type locked in the chase, it was a name, there was about every font ever made in it, roman, italic, copperplate, lite and bold, i couldn’t figure out what face they were trying to use. Before scrapping it i put a little ink on it and rolled it by hand, the rollers were pitted and had lots of cuts in them, to my surprize it printed fine. I locked up a larger form in the chase and tried that, if you looked at this machine you would never think it would work but the thing printed just fine, it wasn’t pretty but i printed with it for 4 or 5 years. Just trying to say that the right man should be able to weld your machine.