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Kent straight key base conversion


A picture is worth a thousand words, so they say, so here goes. Click on the pix below for a slightly larger version:  I had to keep the pix small to accord with the attachment posting rules.

Pic 3 might need a little explanation: to the right are two different shoulder washers threaded onto a paper clip to stop them rolling around. Together they make an insulated path for the screw which secures the connection post to the base.  I used two identical washers for the lower contact (also pictured), whose spigot is a perfect fit in one washer. The second washer insulates the machine screw from the base as it engages the threaded spigot from below.

Pic 4 also needs a little explanation: using the shoulder washers elevates both lower contact and rear bump stop by the thickness of the nylon.  The shim constructed of 1.6mm thick brass serves to preserve the relative position of lever, lower contact and rear bump stop.

I decided to break away from the traditional black for a metal key base and I went instead for a cream/ ivory shade instead. I think bright brass goes well with that. I wanted a base which felt a little more organic and tactile in the hand, so I rounded the corners and edges. (I also think paint sticks better to curves than right angled edges!)  Unlike the KT1, this conversion retains the traditional binding posts, a look I like.  I used rubber self adhesive feet.

You may notice I modified the knob; fortunately for me the M5 threaded rod screwed into the knob base was easy to unscrew, which made it a trivial job to cut off the cylindrical section to produce a knob much like the Navy style speedX ones. Compare pic 5 and pic 7; it's a tiny difference but doing that made it much easier to hold. Now I can comfortably rest index finger on top,and grip either sides of the knob while the lower surfaces of thumb and middle finger rest on the skirt.  It won't improve my CW but at least I'll be comfortable when sending QLF morse!! The fit is a personal thing: all hands are different. This mod suits my hand, simple as that.

Some may think there is too much base on display at the front. That is both true and by design: ultimately I intend to extend the lever with a shaped piece of spring steel. The extension will be covered by the knob skirt. The final result will be a lever ~2 cm longer with a minute amount of spring. I'm interested in seeing what the action feel will be. (Each to his own!).

The finished job is nice to use and quiet when set up with a reasonably narrow gap. I'm happy with the final result:  now I'll have to get to using it.   ;D

As a tribute to they way Kent keys are engineered, there is no sideways play I can manually detect in the bearings: this in a key which could be 20 years  old. Superb....

Weight of key is 1.509kg or around 3lb 5oz.  It  feels grounded: anchored may be a better description!!  ;D  I hope you like the end result. Working on 1cm thick steel with a basic set of tools was difficult but really quite rewarding. If you have questions or suggestions, don't hesitate to write in.


Congratulations Vic. A superb bit of engineering and a key to be proud of!!


Kind of you to say so but the real credit should go to Kent for that pivot block: I can't imagine anything better.

You did mention using a hacksaw on marble in another post: I've done that on beautiful white Italian marble: marvellous to work with. I've also filed it and smoothed it with a belt sander! Delicate filing, then draw filing is a great way to chamfer edges. 

In my murky past I've had experience of building dry stone walls on a relative's farm. I learned it's possible to cut larger sheets of Derby gritstone down to size by gently tapping repeatedly along a scribed line. Eventually the stuff 'gives in' and gently parts where you want it to. Smack it hard and it just shatters every which way.

That gave me an idea: now and again Aldi sell inexpensive kitchen worktop protectors of sawn and polished stone. The stuff is black and twinkly. I'd guess the twinkles come from feldspar inclusions; it's like a black version of the polished blue-green larvikite found  on many bank fascias.  It would be good stuff for key bases.   

I've a cheap tile cutter which came with a diamond dust cutting wheel. Setting the wheel at a shallow (2~3 mm ?) cut would make it possible to cut trenches across the face side, using the trammel guide to keep things square. Sitting the slab on matchsticks it should then be possible to go through the tapping routine  along the trench line until it parts.  The end result could be quite attractive: polished top, nice, disciplined right angle edged sides which become 'rough hewn' 2~3 mm down, depending on the depth of cut. Once dusted and sealed with varnish it could be the basis of a unique 'feature' key base.

What do you think of this idea? Once on the 'key base' trail there's no stopping!!



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