how does the mill shift into back gear?

LEEQ

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I know to push lever to the right, I know to put the out/in selector in the in position turning belt if necessary. I know the sub assemblies all seem to check out. When I put them together, the gear box I know will shift into in will not. So when assembled, what happens when I turn cam ring counterclockwise and shift into in? Maybe that will help me diagnose what is wrong.
 
One wild card I know of is the position of the two very small set screw securing the cam ring pins. This machine had been gone through and slapped back together with most of it's parts. The book says to note the position these were in, but I know I can't trust the work done before me. does this possibly solve my issue?
 
Well, I've been studying and tinkering in my free time. It appears to me that when you shift that cam ring over to the right that it is supposed to raise the pulley assembly off of the gear box. It also appears that mine is not raising quite far enough to disengauge from the gear below it. Any thoughts as to what could be causing this? If I don't pull the pulley housing down tight, it works as intended.
 
http://hqtinc.com/steppulleytophousing-1hp.aspx#

http://hqtinc.com/customimages/quill_housing.htm

I would suspect there is a burr on item 31, the cam ring and 11 the bearing sleeve. That ring groove gets pretty banged up and burred the lever could be bent 32, those small pins 10 that screw in could be burred in the straight screwdriver slots. Pull that assembly out and move everything on your work bench. Usually when it's assembled when you put it into direct drive I have to pull on the belt and you hear that bearing sleeve fall and it will slap into place or the 2 splined gear hubs 55 and 19 engage. I normally hear someone say when they are engaged they rattle, not they don't engage when they are worn out. Just check for burrs and dings all over. File and stone everything to be safe. Don't file hard unless you find a burr.

I seem to recall there is a spacer between the lower spline 55 and the gear 43 but it isn't shown. The spacer is there to engage the teeth of the spline to the correct depth . I have seen where the top housing gets out of alignment and a simple Loosening those 4 nuts, # 62 and giggle it around, move the quill up and down takes care of it. I can't find the 4 Allen bolts (might be a small one in back under it too, been a while since I did one. that hold the top cover in place, but loosen them too and move everything around, up and down and then tighten everything up.

As I said I would pull the top part apart first and check the lever and the clearance between the cam ring and the sleeve. Get a smooth cut file and a stone and file these surfaces lightly feeling for a burr. I would spray everything down good with brake cleaner (and for the safety police reading, wear your safety glasses and lightly oil it while assembling. and do it in a ventilated area) That should move with ease when they are assembled on the bench when moving that lever. I would only oil that assemble and not grease it. Check the housings for burrs, some one may have pried up on the housings and burred them too.

Take a look at that and let me know. Good luck! Rich
 
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Rich, The machine works fine with the back gear "out". when you shift the cam ring lever over to the right it raises the pulley and all, but not completely out of engagement. When you shift the back gear lever "in", it does shift, but locks up. That is due to the fact that the gears locked together for direct drive, are still together a little bit. As I understand it, the flat gear under the pulley needs to raise high enough to seperate from the gear box so it can drive the spindle with the back gear insted of the pulley. I hope all that makes sense. I just got done digging into the gear box on a tip from a tech. All appears to be well. I did some stoning, cleaning, and lubing and have it almost back together. I'll put that flat belt pulley and nut back on tomorrow. Hopefully I will figure out how to get the Top housing assembly apart. I think that's the next place to look. I've put a lot of uumphff on it and that first outside ring with the cam pins in it is on there! Didn't budge yet. This is turning out to be a pretty good head scratcher. This whole process is quite the education.
 
GRRR. Frustration, GRRR. Trying to get the pulley assembly from the upper housing to surrender. Trying. The outer bearing ring doesn't want to move so I can have a look see inside. I got the inner one to give it up, barely. I wonder if this was put together with a sledge hammer. I really hope my problem lies inside of this housing after all the struggle. Any insight would be greatly appreciated. I wouldn't be upset at not having to take this apart. Or at least knowing what to look for.
 
Just left my mill at the shop and had an exciting thought. I have already been through the quill housing. In the process I found a part foreign to a name-brand bridgeport. Possibly chinese mill parts. The thought that dawned on me was this, what if that cam ring is from another mill and not lifting quite enough. I can shim it and probably make it lift enough to disengage the pulley flat gear from the gear box. Why can't I have these thoughts at the shop instead of home at bedtime?
 
In answer to my own original question. This bport shifts into back gear only if you put .050 shim under the cam ring allowing it to seperate the drive train enough for back gear drive and still engage well in direct drive. I might break down and get a pin spanner and hook spanner at a later date to ascertain if the lower gear housing or upper pulley housing assemblies might be snugged down a little more, Oh say about .050 between the two.
 
I wonder if you could machine or file the pin grooves a little further?
The thought had crossed my mind. If I find there is no slop that needs taken up I will look into that possibility a lot harder. I would love to limit part purchases. I've got a kick out of manufacturing my own one off tools instead of b uying fancy storebought. If I can doctor up something I already own I'm all for it.
 
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