Friday, October 30, 2009

Monday, October 19, 2009

The 2035ER Taig Boring Head

Taig sent me their 2035ER Boring Head to test out. The boring head is now for sale: 2035ER Boring Head $45.00

The boring head comes with two import carbide tipped boring bars.

This is a simple boring head. The large cap screw adjusts and locks the dovetail. The small setscrew front and back are used to adjust the position of the boring head. There is no graduated dial. You just adjust it close, and tweak the front and back setscrews to get it close, measure after cutting and adjust a little more. You can of course place an indicator against it to measure travel and I don't think it will be long before someone clever modifies it to have a typical screw feed. The boring head is made of aluminum and has a 3/8" shank.

As you can see it is a simple design.

Opening up a 3/8" hole.

As you can see I got a tiny bit of chatter. This is the biggest problem with boring on small mills. You need to take the time to experiment when boring with different feedrates and depths of cut. Generally you want to bore at the slowest spindle speed you can.

A large diameter hole (yup, same hole, I like to test things thoroughly). Again you can see the smallest amount of chatter.

Boring out a steel bushing. I did this at 1000 rpm just to see whether those with the 1/4hp mill motor could use the boring head. Again I got a small amount of chatter but overall the hole is round.

This is the largest circle the bar will bore with the boring bar in one of the holes, about .4"

Unfortunately this is the smallest hole the bar will bore in the next hole, about 5.5"You can get around this problem by rotating the bar 180 degrees (put a flat on it!) then you get a range in between the large and small range.

This is the largest hole, about 1.25" so the range of adjustment is about .7"

Wednesday, October 7, 2009

Some Projects from Stephen Ellacott

Stephen Ellacott sent in pictures of his latest projects.

"I finally got your indexing plate mounted with a simple indent pin arrangement on the top of the tailstock - works great! Thanks! I made a simple jig to help remove the headstock pulley - 6 1/2" of 5/16" steel rod with a counter bore in one end to fit the point of the gear puller and turned down to 1/4" for a length of 1" at the other end. It is inserted through the headstock with the 3 jaw chuck mounted and the jaws tightened on the reduced part of the rod. The gear puller can't push the shaft through the 3 jaw because of the lip of the cut. I also made a simple spindle threaded 1/4-20 at one end and used it and a washer to hold the pulley on top of the vise while I drilled and tapped the three holes. The plate spins very well without any wobble at all.The indent pin is 5/32" in diameter and tapered to ensure it centers every hole in the indexing plate. It doesn't go all the way through the plate and has a slightly rough finish to stop it from dropping out. It is stored in the top right of the indent pin plate when not in use (see the second picture of Dean's center).In the first picture you can also see a small steel plate I use as a magnetic mount point for my test indicator on top of the headstock and the most amazing piece of brass swarf! After a year of dodging sharp little brass needles I finally found the recipe for turning brass! Zero top rake, 7 degree front/side rake and a 20 thou deep cut at 2100 RPM for a 1/4" rod. I was enjoying turning down the brass pin so much I had to scrap the first one!"

"A modification to Keith's excellent sharpening jig (well worth the effort to make!) which allows you to use it on a drill press without a vise by clamping through the center hole or slots on the table. Much easier to reposition! I also use a hard felt wheel and honing compound in the chuck with the jig to get a "scary sharp" edge on my cutters."

"Taig vise clamped to the drill press using a couple of vise clamps. The basic clamp design is on the Little Machine Shop web site, I just scaled it down for this vise."

"A modification to Dean's headstock center using a coupling nut tapered to fit the pulley. This gives you a self-centering rig which cuts down on vibration quite a bit."

Front view.

"3/4-16 spindle for the Taig chucks made from a 2" 3/4-16 bolt. The trick is screwing the bolt into the front of the four jaw chuck (without jaws) or the machinist's plate then parting off the head and turning the shaft down to 3/8 or 1/2". This ensures concentricity between the threads and the newly turned shaft. The nut is split and used to hold the machined spindle in the mill to cut the Weldon flat without damaging the threads."

Posted on cartertools.com as well.