C&P main shaft shifting to the right
I had to take my C&P 12x18 apart to move it. It’s moved and put back together but something is awry. Now when I turn the fly wheel the large gear cam and main shaft move out gradually about a quarter of an inch from the press. If you look at the small lock cam you can see the end of the shaft retreats .25”.
I have pushed the large cam and shaft back in but it continues to back out gradually by turning the fly wheel. Does anyone have any clue why this is happening?
Possibly because, there are usually retaining collars inboard of the main frame to keep shafting in the correct plane/orientation. Has one been overlooked for tightening.
probably a sign that one of its bearings is more worn than the other, too.
both the main gear and head cam are a press fit on the main shaft. is the main shaft flush to the face at each end? some older machines, the head cam slides on “uncomfortably” easily. there are fixes for that.
ericm, I think my head cam slid on a little too easy and just doesn’t feel like it is locked into place even thought the arms are attached and the key has been inserted.
I attached photos to the head cam and shaft, one with the main gear and shaft pushed back flush and then a second photo after 6 or 7 fly wheel rotations.
(Not that it is relevant but I included a third image of the large gear as well. it seems to be stable on the shaft)
Thank you.
IMG_7087.JPG
IMG_7089.JPG
IMG_7088.JPG
Heck that shaft head has taken a beating, sometime in the past to the point where the iron around it has had some metal beaten of it, and is that really a crack radiating out from the centre, old or new, is it spreading?????Did you use a metal only hammer, or with wood so no metal to metal bashing , or a rubber mallet?
It looks to me that the pin in photo 1 & 3 is the one for the flywheel.
All the pins on both sides of my press go in flush with the gear and shaft. That one can’t possibly go all the way in.
No, the thing that looks like a crack in the main gear photo (I thought the same thing) is a trail of oil.
The pin, no clue. But the current pin/key in my fly shaft is sort of hooked at the end. Both pins in the main shaft are more like straight rectangular.
I only use a plastic mallet filled with sand and the beatings took place before I acquired it. But are you saying I should replace that shaft head?
Back to the topic at hand, there are no collars that go on the main shaft to my knowledge. I can’t figure out why the shaft and main gear back out. I started thinking maybe I loosen the collars on the back shaft thinking that maybe it would “right” itself but no change.
Any ideas of how to correct?
It may simply be loose after reassembly.
We have a press that the gear kept backing off, shaft going inside the hole. We finally put a small machine screw in to make it stable. The pin was all the way in even with the surface.
did you take both the main gear and the head cam off of the shaft? is so, are you sure they went back together in the proper orientation?
The head cam, actually to be fitted correctly, should need to be heated to slide on. i have seen these though, slide on easily. If your cam is sliding out like that under no impression, it is way too loose. the gear side should be flush. is this shaft too long?
pic shows single burner hotplate i use to heat the cam with.
head cam tools.jpg
Seems like the Oft used expression comes into play here i.e. *Can not see the wood for the trees* see loyaltype,s second paragraph above, the obvious is being stated, e.g. current pin/key is sort of hooked at the end, — has to be a Gib key which are normally (very gradually) tapered, Ex suppliers and filed down on fitment retaining the taper,! and then, tapped in with Copper, Brass, Nylon, Hide, hammer.
The pulley, sprocket, head cam, etc etc.is aligned in both planes exactly as required the GIB KEY is fitted in such a way as to allow for subsequent removal (if ever needed) with a slide hammer OR, as has been quoted many times before with 2 opposing fine taper wedges.
The point being that the Gib Head key stops completely and permanently any creep >out OR in<, by the pulley, sprocket, head cam etc etc.etc…against the original quote that it is sloppy fit already.?
By the same token, as above, loyaltype,s second paragraph, >parallel keys in the mainshaft etc< would be the expected norm, i.e. no access for slide hammer but being parallel would be grub screwed —- variation of foothillpress,s solution above.!
Re, the apparent creep on shot,s 7087 & 7089 again >it aint rocket science< once the creeping pulley is in its correct orientation, 180 degrees opposite the Key, (which ever is used) drill/tap and thread the shaft and the pulley 50% into both parts and use One (1) approx. 1/4” whitworth grub screw, Allen socket type, 100% foolproof, 100% secure, 100% extractable if ever needed.!
Perhaps check out the *Taper lock pulley system* for confirmation.
loyaltype says the gib key is in the fly wheel shaft, a proper place for that type of key. Loyal clearly states that the keys in the main shaft are straight cut. normal for this shaft. Gib Head keys are Not used on the main shaft..
my point is the shaft is normally flush with both the gear and the cam when fitted correctly. there are no collars on the main shaft as the gear and cam hold things in place. a collar inside the frame would not prevent the cam from sliding out anyways. Mick, you are a great contributor on here, but man you waste a lot of time, wandering off “into the woods” as you say
if the cam is sliding out just by turning the press over, the cam is way too loose. if this turns out to be the case, using drilled, tapped, and counter sunk, Flat head machine screws will help. BUT we need to determine if this problem can be solved other ways first..With a cam that loose on this size press, you would never be able to apply impression strength that this press is capable of, and probably expected.
I am really scratching my head because when I disassembled I was really careful to take notes and photos. And I was very methodical in making sure I put it back together the same way. I do remember that the head cam was easy to dislocate from the main shaft. I took this thing apart a little bit each day and the say I took out the main gear and shaft and the head cam took maybe 5 minutes. From what I am putting together, that was too easy?
FYI - The key is not flush with the end of the shaft but rather sticking out about a .25 of an inch. I was reluctant to get it too deep for the reason of making my job much harder if I have to take the head cam off soon if I realized I made a mistake. Could that be the reason? Should I go ahead and tap that in with a rubber mallet?
I will stand corrected a bit here. i dug to back 12x18 and the shaft does stick out about a 1/8 inch on each end.
the key should be a straight cut, thus it is not part of the tension on the fit. Check again for any cracks in the cam, if one is there, is likely through the pin for the side arm..you can put the side arms on, and roll the press closed by hand… place a piece of wood into the impression area so that the bed, closes on the wood. this will put pressure on the cam and possibly expose any crack. the cam is loose for a reason. maybe find out from former owner some history on the press.
i will be contacting you privately, watch your spam if you don’t see it.
PS. yes,,,, way too easy……
Yes the key is straight cut. And I don’t see any cracks anywhere on the head cam.
I tapped the key in a bit more and got it nearly flush. With a few hand rotations there seems to be no sign of the shaft backing out. I will test it a few more times before I say this is fixed.
okay, i messaged you. just drop a note if further assistance is required.