Machinist

[Lawrence London <lfljvenaura@gmail.com>]

Poor Man's Power Knee
http://www.practicalmachinist.com/vb/bridgeport-hardinge-mills-lathes/poor-mans-power-knee-116302/

1. Something I made last weekend. Material is 4140 pre-hard.
   
   
   
   There is a drawing also posted on Photobuctet.
   JR

2. 
   

   I have seen that done with an air ratchet too. and saw a table drive made from an old B+D drill. worked good.

3. Randy,
   
   Go to WWW.photobucket.com
   
   Then for album put JRIowa. There are 2 folders, one of the power knee and the other of shop pictures.
   

4. 
   

   Hi JR
   I got your drawing, thanks
   Now how did you make the taper
   cuts to fit the nut????
   
   Thanks
   Randy

   
   

   Don, Sherwin-Williams high solids epoxy floor paint. 1 coat.
   
   Randy, I used a 5/32" carbide end mill. After indicating the part in, I moved over 0.080" and started making passes. .025" deep per cut & 5/16" deep total. Then move over to .075" offset and cut the sides with a new endmill.
   JR

   • Like
5. 
   

   JR, what brand of chuck is on the cordless drill? Is it original? Metal or plaskit?

6. Ralph, it is a stock Milwaukee chuck. Steel.
   JR

   The kondia mill at work had a snap ring holding the knee lift handle on so I didn't want to upset the other oldtime thinking machinists by removing the ring so the handle would come off so I made my drill driver to slip over the short shaft on the outside of the snap ring. it was made in the lathe with aID to fit he shaft end and ID to match the OD of the radius of the handle. I cut the part away to clear the handle. It is long so it clears your hands and drill. I use a Harbor Freight low speed 1/2" drill I milled 3 flats on the shank

   Last edited by garychipmaker; 03-05-2013 at 05:30 PM.
7.