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Kearney & Trecker 307 S-12 Ram Style Mill Question

Dan_Lin

Plastic
Joined
Mar 5, 2018
Good Evening All. Last weekend I purchased a K&T 307 S-12 combination mill. I purchased the machine under the claim that it was in operating condition when it was removed from service back in 2013. The 1st problem that I observed is when we loaded it on the trailer. I attempted to lower the knee and when I tried to turn the handcrank it was locked up solid. The gib clamps were loose and there was zero movement. I am not familiar with the machine so am I missing something very basic? This mill was purchased from a gentleman named Nethawk who had posted here on this same machine back in 2006. With the help of this community he was able to bring the machine back into operation. At least that is the conclusion that I come to when I read through his 2 page post. He passed away many years ago and his son sold the mill to me this past weekend. In his thread back in 2006 titled "Where to get parts for a K&T mill?" he had a very similar issue with the knee. He claimed to have replaced the elevating nut and the problem was corrected. I can't imagine that the nut would have failed already. Any ideas? I will post some pictures of the machine after I unload it this weekend. Thanks, Dan
 
What does the column/knee interface look like ? Is it nice and clean or is it rusty ? Are you sure the knee locking levers are actually releasing ? Has the machine been left with the vertical feed lever engaged ?

You can always make sure the knee moves easily on the column by releasing the screws the hold the elevating screw bracket onto the base under the knee and see if you can gently bar the knee up and down with a large crow bar.

Regards Tyrone.
 
Slim chance, but I have to ask - any wood block under there preventing lowering? Common to have such when transporting

Also - if you have a missing or broken lock out the feed can be engaged - and you are not going anywhere in that condition
 
Thank you for the advice. There was no wood under the knee for support and the interface actually looks pretty clean. I attempted to move the lock plunger in and out on the knee's power feed lever. I had to use a pair of plyers to get it to shift. Unfortunately with the plunger in either position I couldn't get the lever to engage in the up or down feed position. It also is stuck. I will get it off the trailer on Saturday and take a much better look at it.
 
Attached are two pictures of the machine that I purchased. This weekend I rewired all of the machine's motors for low voltage and swapped out the oil. The table and saddle feeds and rapids work properly. The vertical and horizontal spindles work properly. The knee is locked up solid (hand crank is bound up and the feed lever won't engage). I loosed the knee's gib and both gib plates to try to see if that was contributing to the problem but no luck. I now plan to remove the table/saddle assembly and the distribution box to get at the elevating screw assembly unless anyone has some other advice. Thanks.

Kearney_2.jpg
Kearney_1.jpg
 
It's acting like the feed is already engaged. I have a k&t and when the feed is engaged with the machine off the handle is locked. But you say it's not doing anything when turned on. You may have to take apart the knee in order to find the problem. Adam Booth had an issue with a very similar machine, maybe you can watch his vids to get an idea of how to take it apart.
 
Just a note, if you haven't already done so....

Don't forget to replace the heaters in the machines starter, since you went from high voltage to low voltage. You'd be surprised how many miss this little detail, and cook their heaters.
 
Attached are two pictures of the machine that I purchased. This weekend I rewired all of the machine's motors for low voltage and swapped out the oil. The table and saddle feeds and rapids work properly. The vertical and horizontal spindles work properly. The knee is locked up solid (hand crank is bound up and the feed lever won't engage). I loosed the knee's gib and both gib plates to try to see if that was contributing to the problem but no luck. I now plan to remove the table/saddle assembly and the distribution box to get at the elevating screw assembly unless anyone has some other advice. Thanks.

View attachment 276643
View attachment 276644

That's a nice looking machine. I'd block the knee up where it is and remove the screws that hold the knee elevating screw bracket in place. You could then try to turn around the bracket by hand. At least that will tell you wether the knee elevating screw has seized up or not.

I'd also remove some of the panels on the side of the knee and have a look inside. See if you can see something obvious before you go to all the trouble of removing the saddle and table.

Regards Tyrone.
 
Thank you all for the advice. I was finally able to dedicate some time to the machine yesterday. I removed the distribution box and it appears that I have 2 different issues to deal with. First is the knee feed shaft clutch sleeve and second is a seized up elevating nut. For the sake of this post I will only discuss the clutch sleeve issue. The sleeve is extremely tight on the shaft splines. I disengaged the shift fork from the shifter shaft and the sleeve was locked onto the shaft (would not move). I was able to get it to shift back and forth with a firm strike from a mallet. I started to disassemble the feed shaft to remove it from the box. Unfortunately it appears that the last time someone was in there they relied on a big hammer to get the unit reassembled. I am trying to remove the serrated collar from the front of the shaft and can't figure out how to get it off. I tried to use a bolt puller and then the jack-screw holes in the dial collar but it didn't want to move. The parts manual states that there is a set screw installed on the collar but this didn't have one. I attached 2 pictures for reference. Please let me know if you have any suggestions.Picture2.jpgPicture1.jpg
 
I finally got the mill back together this past weekend. I attached a picture at the end of this post as to how I was able to remove the serrated collar off of the shaft just in case someone runs into the same problem in the future. Once I got the splined shaft apart I filed the burrs on both the clutch sleeve and shaft splines. After a couple hours of inking and filing the sleeve slid freely and worked as it was designed. Next I pulled the table off and removed the elevating screw/nut assembly. The bronze elevating nut was seized to the screw. With a ton of heat and a 3 foot spanner wrench I was able to get the unit apart. The threads on both the screw and nut looked good. It appears that this was a homemade replacement nut. The major & minor diameters of the nut and screw were size for size. I bought a 1.375"-4 Acme tap and ran that through the nut and polished the screw on the lathe. No issues after that. The machine went back together and everything that I intended to fix works as it should. The only issue that I have now is the hydraulic pump in the knee appears to be sucking air. It would stop the power feeds/rapids. The constant pressure is around the 200psi range but varies about 40psi as indicated by the gauge needle bouncing around. With the machine off I pulled the side cover and there was approximately 1" of oil on top of the filter. Is it possible that I have the filter positioned improperly and I'm starving the pump of oil or could the pump be sucking air from somewhere else? Shaft Clamp.jpg
 
The problem has been identified. I pulled the oil filter today and ran an unrestricted tube off of the pump and into the oil. The constant pressure increased to 250psi and stabilized. The mill sounded as it should and the feeds/rapids worked great. I will install a replacement filter and the machine should be in good working order.
 
I installed a new filter today and the machine is running well now. When I purchased this machine it didn't come with the overarm supports. Does anyone have a pair that they are interested in selling?
 








 
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