Part 8 by Jason Ballamy


I did not have any 5mm thick brass so thinned down the end of a piece of 1/4" material and then drilled the 2.0mm hole at least 31mm deep.

With the work now on its side the recess was milled out with a 6.0mm cutter to give the required 3.0mm radius to the internal corners.

After cutting off from the parent bar the back face was milled to finished size and then the 1.0mm step cut from the lower end.

Turning the part the other way up the larger recess can be milled out, the two 2.0mm holes drilled and then countersunk then finish off by filing the 2.5mm radius around the upper screw hole.


This started life as a Stanley knife blade. It is best to shape the knife blade after the steel block has been soldered on just in case it moves about during silver soldering. Also worth leaving the block a bit long to start with so just make the 5x8 dimensions to finished size then solder.

The blade can then be roughly trimmed to size making sure the edges are true to the edges of the block. With the rod guide screwed into place machine a point onto some 2.0mm rod and pass that through the guide and use the rod as a scriber to mark the position of the M2 hole.

The hole can now be drilled and then tapped M2 and the block rounded over. I would suggest leaving the final shaping of the shutter until it is mounted on its rod.


This is quite a simple job, face the rod to length and cut the M2 thread on each end to the lengths required.

This shot shows the finished part, the fork and cam follower roller will be covered next time.

Part one here  Part two  Part three Part four  Part five  Part six Part seven Part eight

Part nine -

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