8 x 12 C&P adjustments

I found the problem. THREE of the bolts holding the platen are sheared off above the adjusting nuts!

I’ll have to remove the platen, try to remove the broken bolts from the platen, and figure out a way to replace them. I’m guessing that I can figure out a way……

That still doesn’t solve the problem of the brace not getting under the lugs on impression. Does the roller that controls that action have an adjustment??

Sheesh!

Does anyone know where I could get four platen adjusting bolts for this 8&12 C&P? I figured out about when the press was built…..since it has a ZIP Code on the builder’s plate, it had to have been manufactured between July1, 1963 and the end of C&P production in 1964!

By brace, do you mean the Rocker Lock as described here: http://www.boxcarpress.com/flywheel/manuals/CP_PartsList.pdf on page 6 in the lower right?

That’s the one! Thank you for the link to the parts list. I see also that the “bolts” that I referred to above are impression screws…..any help on this would surely be appreciated. Thanks.

Updated. Is the Rocker Spring broken? or the Lock Roller? Is the Small Head and Lock Cam turning? A picture sure would be nice.

BTW the serial number should be on the upper left corner of the bed. It will tell you when the press was made. Look here: http://www.greendolphinpress.com/letterpress-faq.html

Arie, I added a photo of the problem…..as you can see, the rocker on impression is about 1/4” low, and the rocker brace cannot get under it. Is there an adjustment for the rocker at the cam roller or something? This press was used for diecutting, and may have damaged something besides the platen adjusting screws. I hope not….. I’m still in the process of moving the press indoors and haven’t had time to tear into anything yet.

The serial number of the press is NB 619. Doesn’t seem to be on the list on the link….

Hmmm. The only thing I can think of that would explain a rocker coming down too far would be very worn rocker and/or frame where the rocker sits on the frame), probably due to poor lubrication. With the press open grab the platen and shake. It shouldn’t move any. Mine is an OS from 1910 and it moves a tiny bit. Most of the give in mine seems to be in the cam roller and stud inside the large gear. If your’s moves a lot (and in places other than the cam roller), you got problems.

To verify you may need to take the platen off (sounds like you’ll need to do that to replace the impression screws anyway) and then loosen the bolts off the rocker boxes (first one side then the other after putting the first one back). The rocker will stay in place without the boxes (barely) and you can inspect for unusual wear. If you want to remove the rocker, I recommend a really strong friend or an engine hoist or some other way to suspend it without muscle power. I can lift one from an 8x12 or 10x15 by myself, but only if the bed has been removed and even then I want help if possible. The rocker is awkward to hold and lift into/out of place. It seems to want to go back in best in the closed position. You need to remove the cam roller and stud from the large gear AND the gripper bar roller cam and screw from the gripper cam before you try and lift the rocker out.

C&P disassembly isn’t hard, but it requires care and double checking that everything is ready to go to the next step.

If you do see a lot of wear under the rocker boxes, I’d consider another press. If that’s not where the problem is then it’s time to scratch your head and ask for more help. Where are you?

After I get the press into my garage, I’ll remove the platen and see if I can ascertain anything else…..

I’m in Walker Lake, Nevada, about 100 miles from Carson City on Highway 95 between Reno and Las Vegas.

Kinda far away from Michigan. Look for printers in the area for some help.

Wasn’t thinking to clearly yesterday apparently. The gripper cam is attached to the platen and the gripper bar roller cam needs to be removed before the *platen* is removed. Sorry.

I had the same problem just this week with my Kluge 10x15. Luckily I worked out how to fix it. You’ll need to take out the rocker as described by Arie. The rocker arm has shifted on the shaft of the rocker. The arm holds the cam roller which connects to the big gear wheel. On my Kluge there where two metal pins holding the arm in position on the shaft. You’ll need to remove the arm, rotate it about 1 - 2 degrees in the right direction and re-pin it into place. In my case, I way lucky and was able to fix it with a hammer and some help from a friend. Looking at the photo, your machine is a little more out of alignment than mine. Once you have the rocker off inspect the position of the rocker arm carefully. As you’ll only need to rotate its position slightly to re-align your machine. If you can’t get the rocker arm off with a hammer, you’ll need to take it to an engineers workshop.
With the problem you have, it makes a severe impact on uneven impression. I’d say someone has tried to adjust the 3 broken screws too much trying to fix the problem. Take your good screw out and get 3 new ones made by an engineer.
If your not mechanically minded, give up now. Otherwise you’ll need two strong people to lift out the rocker. You’ll also need a bit of luck to get the adjustment right first time.
I think this problem has been caused by very heavy impression over a long period of time. Well that’s how I caused the problem on my machine. I have the same 8x12 machine at home, so I’ll have a look when I get home to make sure these instructions are correct for the C&P.
Good luck!

Russell,

Thanks for the insight. I think you are probably correct in your analysis. This ought to be a lot of “fun”……..fortunately I am pretty mechanically minded and love a challenge. I guess that’s why I am fascinated with old machinery……no electronic wizardry to contend with. My other “project” is a Model 31 Linotype. Now there is a piece of machanical genius!! I’ve run Linotypes ever since I bought my first Model 5 back in 1965 when I was in high school and helped start our local newspaper in 1966. The paper is still going, but all computerized now….www.chilkatvalleynews.com

Bill Hartmann
Walker Lake, NV

Got the platen off ok. My next job will be to drill out and use an EZ out to remove the broken studs. Does anyone know where I could purchase new or used adjusting screws? Or where I could find a machine shop that could manufacture new ones?

When it comes to lifting off the rocker, I have a good chain hoist and a handy overhead rafter. I’ll let you all know how that goes (or ask for help again if I get stuck).

This is an awesome site for letterpress help! Thanks!

I removed two of the broken screws with a pair of vise-grips. I have to drive 12 miles into town (Hawthorne, NV) to get a larger EZ out to get the last one.

Question: To remove the stud holding the cam roller, it looks like it will come through a same-size hole on the gear…….I tried backing the nut off a couple turns and hitting it with a hammer. Didn’t budge. I’m wondering how much force it should take….I don’t want to damage anything in the process. I’m assuming it simply has a shoulder on it and no other means of holding it in?

Bill: Yes the stud comes out through the hole in the gear. Usually doesn’t take too much force, but it does have to be lined up carefully. I once took apart a press that had not been properly lubricated in its past and someone had tried to make up for the wear on the stud/cam by wedging in a bit of copper spacing. That one was a bit stubborn but came out with a few firm taps. I take the nut off and use a length of 2x2 inch wood to protect the threads. Wedge the 2x2 up against the stud and hit the end of the 2x2 with a hammer. Make some arrangement to catch the stud as it pops out or it will hit the floor and mar some very precise machining.