Taig Mill: More Upgrades

I had a chance to do a bit more work to the Taig Mill. Along with the new motor I purchased a new X-axis leadscrew, adjustable backlash leadscrew nuts and a bearing block assembly.

The X-axis leadscrew had been damaged in shipping. The damage was not bad enough that it didn't work, but I wanted to get the adjustable backlash nuts to help reduce backlash and since I would have it apart I may as well change the leadscrew. The end of the leadscrew had been damaged enough such that it would probably not work with the CNC conversion later so it would have to be changed eventually regardless.

Changing the leadscrew was pretty simple. First turned unscrewed the two screws holding the bearing block on the end of the X-table. Then I turned the lead-screw out of the leadscrew nut. The leadscrew nut could then be replaced with the new adjustable backlash model. Prior to doing so I cleaned and oiled the gibbs and ways, since it was all exposed and easy to get at that point.











The next step was to remove the crank and the dial from the old leadscrew by first removing the hex nut. Be careful not to allow the key to fall out from the keyway in the shaft if you need to reuse it. It is small and can be very difficult to find on the garage floor. Not that I know, I am just assuming that this would be the case. I next placed the new bearing block on the new leadscrew and assembled the dial and crank onto the new leadscrew. The new leadscrew included a key, a washer and a lock-nut. I've read to be careful not to over-tighten then nut as this can damage the ball bearings in the bearing block. I therefore used care to tighten the nut only until I could feel no more slop in the assembly.













I did find that the key was a little oversized and needed to be filed to fit properly. Aside from that it all fit together quite nicely. One thing that I was disappointing in was the shallowness of the mark on the bearing block which one would use, in conjunction with the dial, to determine the travel of the table. If you look at the picture below you may barely be able to see what looks like a vertical scratch at the 12 o'clock position. This is not much more visible by eye than in the picture and I will have to try to scribe it more deeply later. I realize that this bearing block is intended to be used mainly on CNC machines, but if they were going to go to the trouble of marking it at all they may as well have done it deeply enough to be useful.

Once the leadscrew assembly was together I screwed it onto the X-axis table and slid the table into the ways. I then adjusted the ways until I could feel no play, but the table slid with little resistance. At this point I proceeded to thread the leadscrew into the leadscrew nut. I happened to have bought the 19" leadscrew, despite having the 18" table. This will allow me to upgrade the table size later, but it also allowed easier access to the leadscrew nut for backlash adjustment. I was able to have the table in the ways while having the nut exposed enough to adjust. This is done by loosening the set screw in the middle of the nut and turning the two screws one either side until they were snug. Then you back off of the outer screws by 1/4 turn and snug up the set screw. All said and done, I got the table assembled and backlash was down to about .003" which is way less than it was before. I believe that I can get a little more out if I really fiddle with it, but .003" is fine for manual work. I'll obsess about it once I convert to CNC.














Further improvements I intend to make are to replace the other two leadscrew nuts, and to make and install way covers. After that I'll have to tram everything up and I'll be ready to cut some more chips on her.

Taig Mill From Ebay: Update

I'm still chasing the backlash in the table. There seems to be as much as .012" on the y axis. It looks to me as though it is coming from the bearing blocks at the end of the leadscrews where the cranks are mounted. There doesn't appear to be any way to adjust this out. I ordered a new x axis leadscrew and a bearing block assembly as well as the CNC style leadscrew nuts which can be tightened to reduced backlash. I also ordered the 1/5Hp motor which should be an improvement over the 1/8Hp motor that is on it now. It only cost me $30 so I figured it was worth a try. As you can see in the picture below I also got around to wiring and mounting a switch to the Taig. The Taig motor came with a connector wired to it that happens to be the mate to the type of connector that plugs into a PC power supply. That made it really simple to use spare PC power cord to wire it up.


I also managed to wreck the test indicator that I was using to align the vise. I was cranking the handles to move the table to do something and I didn't remove the indicator before doing so. I tend to be really impatient and take shortcuts that end this way all too often. Luckily, the indicator was a $30 cheapy that I bought from littlemachineshop.com rather than a $200-$300 Starret or Brown and Sharp.
I did manage to machine a few pieces out of scrap aluminum that I got from work. I made a few t-slot nuts and two clamps to hold the vise down. In order to clamp the vise down to make those I ground some 1/4-20 carriage bolts to fit in the t-slots and made some clamps on the FDM machine at work. The FDM machine extrudes ABS plastic, so those clamps were not very strong and the vise walked at times, which is why I used them only to make new clamps.
Lee and I got together at his house the other Saturday. I loaded the bio-diesel processor into my truck and dropped it off in one of his garages. I presently have no diesels running, so the ambition to complete the processor is just not there. Lee now has my old Golf and a Rabitamino, so hopefully he'll find the time to get one of them going and the processor up and running too.
After we unloaded the processor we worked on fixing up an old drill press that Lee had because I had none and he had an extra laying around. The press had no power cord, no power switch, and the belt guard had no means of being mounted. Lee fashioned a quick and dirty power switch from a light switch that he hastily tore off of the wall of his garage. He then attached it using some scrap wood that was laying around. Lee doesn't pay much regard for aesthetics, but he gets results.

































The mount for the belt guard was a bit more refined as Lee was itching to show me his wood lathe and used it as an excuse to start it up. The drill press is based around a large pipe Lee turned a piece that would fit into the pipe. He then attached a few blocks of wood upon which the guard rests quite nicely. It isn't beautiful but it works better than the nothing that I had before.


I actually used the drill press to drill and tap the holes in the Taig column to mount the power switch. It was much nicer than drilling a crooked hole with the hand drill. I was also able to chuck the tap and turn it by hand to start the tap straight, thus reducing the likelyhood of breaking the tap. Well done, Lee. Thanks for the drill press.