Pm2700 Onwes - Pic Request

[alex grams]

I am having some issues with the mobile base on a recently purchased, used PM2700. The rod that connects the handwheel to the top of the mobile base is slotted and slips over a roll pin to transmit the force from the handwheel to the lower mobile base. However, when I purchase the unit, the rod had splayed open and needed replacing. I replaced the shaft as well as the roll pin, but only to find out after trying to engage the mobile base function again that it once again failed the same way, spreading out the rod and bending the roll pin. My suspicion is that the roll pin needs to sit further into the slot, and by sitting so close to the end it works out and begins to fail.

Can someone post a picture of this connection on their machine? The slot is about 1" long, but for me the pin only sits in about 1/4" of an inch. I can't really think of another cause for the failures I am having. I took the shaper off of the mobile base, checked the chain, inspected all of the wheels/bearings to make sure they aren't bound up, and I can easily move the chain by putting tension on it. One wheel did feel stiff, but i greased the chain and adjusted everything so its operates smoothly. I wouldn't think this would be the cause, but I am just trying to cover all bases.

You can see the height of the rod vs the (broken) pin. I have the rod to the side to help show their relative heights, but it is still sitting at its appropriate height from its mounting bracket above.

241077

Thanks in advance.

[Ronald Blue]

It appears you have two options. The easiest would be to shorten the male rod by cutting off the rod about 1/8-1/4 above the roll pin or the second option would be to bore or drill the hole in the slotted rod deeper to allow full engagement into the slot. The second option is probably the best fix as it will assure you can get full engagement. A third option would be to shorten the legs but I think that could cause other issues. (Jumping off) I think your diagnosis as to the cause of the splaying is correct. The closer to the end of the slot the weaker the "leg" will be.

[alex grams]

Ronald, there is ample room for the male with the pin to further engage into the female 'rod', it has no problem with bottoming out. The constraints keeping it from further engaging are the bracket which holds where the mobile base is mounted relative to the body, and a welded bracket which the upper unit/handwheel and 'female' rod are mounted to. I don't think either of those are adjustable.

See image:
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Another question for PM owners who can take a peek, does the rod with the roll pin in it move up and down with the mobile base as you turn the handwheel? This would explain the long slot in the female rod to allow the roll pin to move up and down with the mobile base,, but if so, there must be some way to adjust the overall height of the male/roll pin piece relative to the female piece, I just can't see where without tearing everything apart.

[Randy Henry]

Alex, I will try to go out and get a pic of mine. I once had a similar problem, after I cranked the wheels up too high. When I went to lower them, I turned wheel the wrong way and it got stuck, I turned it some more, and....I ended up having to take the entire assembly apart to get the wheels lowered.

[alex grams]

Thanks randy. That is a suspicion of mine too when the replacement rod broke. That is why I took the shaper off of the Mobile base and checked all of the gears and casters. One was pretty stiff to get spinning again.

[Randy Henry]

241087

After looking at mine, you will see I took out the pin and put in a bolt, with a ny-lock nut. I did this a couple years ago and not have any issues since, though I rarely move the machine.

[alex grams]

Thanks randy. Yours looks like the pin is halfway up the slot in the rod. I presume this is in the raised position? Does the pin move down the slot as the base is lowered?

[Randy Henry]

It is in the raised position. It does not slide up-down when I turn the handle. The handle just turns the first gear, which is connected to all the casters by chain, then are moved up-down by a threaded sleeve. If you just purchased this shaper, a couple of suggestions-take out the set screw in the motor pulley, and put some blue lock-tite on the screw. My came out twice (set screw-woodruff key), and PM sent me a new pulley. I put some of that lock-tite on it, and I have had no more issues. I also had the same issue with the set screw on the spindle hand wheel. I did ended up taking both wheel's setscrews out too and putting the lock-tite on them also.

[alex grams]

Thanks, mine doesnt sit nearly that low. I may consider taking a welder and filling in the upper part of the gap on the rod so that the lower end has more support from spreading. When I put another replacement rod in i am going to have someone lower it pretty slowly so I can watch the rod and exactly what is happening with the part. I really don't want to have to buy a third rod at 20$ a pop to fix the problem.

[Ronald Blue]

If the rod does not need to float up and down the slot is there a possibility of turning the rod 90 degrees and drilling a cross hole? If the roll pin hole is 1/4 maybe drill with 5/16 or 3/8 and use a 1/4 bolt with a lock nut and flat washers on it? The oversize hole would allow some movement but with the nut ran up until it contacts the rod it would not be prone to spreading. Just a thought. There maybe be a mechanical reason why that can't work and I am just throwing it out as an idea to make what you have work.