Quick change toolpost for the Unimat 3.

The Unimat 3 comes with a simple toolpost, capable of taking one tool which has to be set to centre height (cutting edge in line with the centre of the chuck spindle) by placing shims under the tool. This is of course fine, but when you need to change the tool you need to take out the shims along with the tool, then set up the next tool with the correct amount of shims under it. This is I find a bit of a faff, although some canny users have various tools with shims superglued underneath them speeding up the process. However, I have worked on full sized industrial lathes and once you've used a quick change toolpost anything else is just hard work.

These toolposts are available for U3s, as original equipment from Emco (which are now pretty scarce) and also as aftermarket accessories. Mine came from Chronos Engineering Supplies via eBay. I believe that these are made in India for Chronos.

It comes with two toolholders and an allen key. Extra toolholders are available, I now have several.
Each toolholder slots into the toolpost from the top, and is locked in place with the cap head screw on the side. The height of the holder can be set by turning the shaped adjuster on the top, underneath which is a spring to hold the adjuster in place once set.

My toolpost had a problem with one of the locking strips, which sat above the body of the post;

This meant that the adjuster sat on the locking strip rather than the body of the post. I removed the locking strip and filed the upper end down;

Its a shame that this wasn't picked up at the factory, but thats the problem with moving manufactoring abroad, you have less control over the quality. But then if you make everything here in the UK no-one would want to buy it as the price would increase.

Here it is fitted onto the cross-slide;

What isn't supplied is an M6 x 55 cap head bolt, which will need to be shortened slightly (a few strokes with a file), and t-nut (not a problem as the one from the original toolpost can be used).

And again, with a boring bar in place;

(The boring bar incidentaly was made by my Grandfather from an old file.)

With the height of the tool being adjusted by simply turning a screw means that setting tools to centre height is far easier,

This should prove to be a usefull accessory, speeding up work quite considerably.

Paul.