Stephen Ellacott's Taig Lathe Powerfeed

Stephen Ellacott sent in pictures of his latest project. This is the first project I've seen that takes advantage of the dovetail on the front of the new extruded carriage.

"I hate lead screws...big floppy swarf magnets....there, I've said it. So I'm working on motorizing the carriage traverse to try to provide the same smooth finish as a lead screw. Here are some shots of the prototype version that I thought you might enjoy. The regular traversing handle and pinion has been replaced with the geared pinion and a block with the Geared Motor (5RPM) and drive gear attached."

"It slides onto the dovetail on the front of the carriage and is snugged against the pinion gear (whatever size you want) and tightened in place. I used two 12 tooth 24 pitch Acetal gears for the prototype - probably brass for the real thing."

"The 12V motor reversing circuit controls the carriage with three buttons- Forward, Stop and Reverse. You must hit Stop before changing direction. I'll package this up in a 1.5" x 3" swarf proof project box when I'm done. It draws about 70mA cutting .0010" in brass at a 3 inch/minute traverse with the one-to-one gear ratio (too fast, but it was easier to layout the prototype using like gears). The goal is to be able to loosen one thumb screw, slide the motor block to the left and have manual traverse back. Total cost - less than $30 (real dollars). The final pinion gear may just be the stock handle with gears cut around the perimeter....Hmmm...may have to order one.."

"A better shot of it installed using dovetail clamping (works great!) with the body cut down to size."

"Another shot of the back of the block. Just loosen the 10-32 set screw and it slides off under the cross-slide knob."

Pictures also posted on Cartertools.

Run of the Mill Projects.

I needed two tee nuts for my Palmgren x/y table. So I found two oversized 1/2" thread nuts and milled them down.

It's tough steel but milled fine.

I reduced the width as well. Then I found that the vise I was mounting would only accept a 3/8" bolt...not a 1/2"...and I found two nuts that fit perfectly in another drawer of clamping hardware...oh well. At least if I need to use a 1/2" stud on the table I'll have nuts to fit.

Turning a grooved dowel for a toy fishing rod repair.

A #1050 3 Jaw Chuck Jaw Boring Test

I thought it would be interesting to look at #1050 3 jaw chuck boring.

A relatively new #1050 chuck, with unbored jaws. I tested runout using dowel pins, which may not be perfect compared to gage pins, but will do for this. With the unbored jaws I found the runout was:

1. 3/8" dia. pin, .001" runout
2. 1/2" dia. pin, .004" runout
3. 3/4" dia. pin, .008" runout

Boring the jaws using the factory supplied washer. I made sure to set the carriage depth stop so that the boring bar wouldn't hit the washer.

After boring.

I thought it was odd that the bored jaws didn't have a uniform width. I'm not sure why. Could be that there's enough play in the jaws that the jaw lifts, throwing off the boring. Or it could be that the jaws were slightly deformed, as I'd been using them for a while unbored.
In any case the results were:

1. 3/8" dia. pin, .003" runout (+.002" over unbored)
2. 1/2" dia. pin, .000" runout (-.004" over unbored)
3. 3/4" dia. pin, .006" runout (-.002" over unbored)
   

So a slight improvement was gained except in the case of the 3/8" pin.

Next I inserted a 1/4" pin far at the back of the jaws.

And bored them out with a smaller boring bar.
The results were:

1. 3/8" dia. pin, .000" runout (-.001" over unbored)
2. 1/2" dia. pin, .002" runout (-.002" over unbored)
3. 3/4" dia. pin, .000" runout (-.008" over unbored)
   

Which is pretty interesting. Note that when I say .000" I mean the needle didn't move even a quarter a division on a .001" indicator but may have wiggled a few tenths.

Next I bored out the jaws without any preload at all, just opened them up about an inch and bored them.

The results were:

1. 3/8" dia. pin, .002" runout (+.001" over unbored)
2. 1/2" dia. pin, .000" runout (-.004" over unbored)
3. 3/4" dia. pin, .002" runout (-.006" over unbored)

Then I rebored the jaws with the factory washer and found that things had changed again...

The results were:

1. 3/8" dia. pin, .002" runout (+.001" over unbored)
2. 1/2" dia. pin, .000" runout (-.004" over unbored)
3. 3/4" dia. pin, .001" runout (-.007" over unbored)

So what did I learn? I have no idea except that it's probably worth experimenting yourself to find the optimal diameter of the preload washer for a given diameter or range of diameters of workpieces. It does definitely suggest that leaving the jaws unbored is not a good idea.

It may be that it's a good idea to undercut the back of new jaws before placing the washer and boring them as any uneveness in the jaws will cause poor preload?

A Small Improvement to a Small Improvement

Before I started the Taig-centric blog I would post stuff on my other blog. A while back I posted that I had made a small improvement to my Taig lathe workarea by rising the lathe up on top of a toolbox. Well, Saturday I stopped at a garage sale and picked up a better toolbox for this purpose, a Waterloo middle toolbox. So now I have 4 drawers instead of 2, and less wasted space.

Making Some Small Delrin Washers

For an airgun project I had to make some small delrin washers.

The delrin was turned down to size and center drilled.

Then I drilled the ID to size.

I ground a thin (.032") parting tool that is not square at the front but tapered so as to generate less of a burr on the finished washer. I held it in the 1171 back toolpost.

The dowel pin captured the parted off washer as the parting tool is plunged into the work.

Adapting a Sherline Boring Head to the Taig Mill.

I had a Sherline boring head laying around and figured I should modify it to be used on the Taig mill.

The two parts were separated. Notice it uses the screw to push the part that holds the boring bars out from the body attached to the spindle. There is no way to adjust precisely in the other direction.

I put two leaf gages in the clamping slot to keep from collapsing it in the 4 jaw.

I turned the MT1 shank down to 3/8" It machined easily.

Mounted in a 3/8" ER16 collet.

With a cheap import carbide boring bar I got a lot of chatter.

Using a good HSS boring bar I managed to get an acceptable finish.

Have Blue's Blog and Frankie Flood...

Michael Guslick, "Have Blue", emailed me about his new blog. Not all the posts are about his work on the Taig, but using the "Machining" category to search will turn up some neat projects like his Taig CNC Mill engraving head. Michael also has a business supplying parts for paintball guns.

Michael recently took a metalworking class from Frankie Flood who most notably uses his Taig lathe to make his awesome Pizza Cutters. Frankie also has a new blog. Well worth reading.

Thomas Burgin Extends His Z Axis

Thomas Burgin sent in these pictures of his Z axis extension.

"Here's a few pics of a quick extending of the Z axis. Moved up 4 more inches then the max. Had to do some work on the end of some parts. This is problably not good for long term use though. I think I will make a better easier way of doing this for when I need the extra travel."

Side

Front

Back

Added to the pictures page.

I also added a link to new Taig User Matt Wellhouser's Blog.

Silvano Villaroel's Watch Case

Silvano Villaroel sent in these pictures of his first watch case made with his Taig lathe.

"I would like to tell you as well I finshed my first watch case the last weekend. I am very happy with that. I think there is a lot of things I could make better and I will but that will be on the second case I will began to work on soon."

Lots of parts!

(uploaded to the cartertools picture page as well)

John Bear Ross's Taig CNC Router Mount

John Bear Ross emailed me these pics. "I fabbed up an adaptor plate to mount a K2CNC router mount to my Taig's head, enabling me to mount a Bosch Colt router."

"Off comes the old spindle..."

"New Mount..."

"New Collets and Nut from Precisebits.com"

"And in she goes..."

Looks great.

John needed the higher speed for milling his wonderfully detailed military SF miniatures.

Pictures also uploaded to the Taig picture page. This blog is definitely forcing me to update pics more often.

Making Scrap on Purpose

This is an odd tale.

A few years ago I bought a shelf full of junk at an auction. Included were a bunch of scrap parts from one of the screw machines. They look like stepped washers. About half of them had 7 holes drilled around the periphery. After tripping over the box for a year I was thinking of taking them to the scrap yard and then out of the blue Felice asked if she could use them for jewelry. So our Widget Earrings were born!
They sold pretty well and we finally ran out of the ones with the drilled holes. So it was my task to replicate what were essentially scrap parts out of the remaining undrilled ones.

I cross drilled a blank arbor for a spanner hole.

The finished arbor. I had to get rid of the thumbscrew as it was too large in diameter. Yes, that's an aluminum blank arbor - that's another long story I won't relate.

The CNC mill was set up and I started drilling.

All the holes drilled.

A Youtube video of the operation.

The Program is short and sweet:
G91
G00 X0Y0A0
M98 P1000 L7
G00 Z1.000
M30

O1000
G81 G99 X0 Y0 Z-.10 R.1 F6
G00 A51.428
M99

I'm going to tweak the program a bit as the G00 X0Y0A0 line isn't needed and I want it to move to the side for loading and unloading after running.