A low-tech (and non-invasive) solution for the heavy Model F spacebar

Cattus_D

01 Oct 2016, 11:50

After reading up on how to mod my Model F spacebar so as to decrease the downward force required to make it register I decided to try a few other things first. I didn't quite feel like cracking open the shell again and was afraid I might damage something in the process of modifying the keyboard.

The first thing I tried was pressing the spacebar down somewhat with a few strips of sellotape, so that only a small push would be required to get the bar to its activation point. This did work - for a single keypress: after pressing the spacebar it would hang.

The second thing I tried did, on the whole, work as intended - and I am using the trick right now. It occurred to me that I could try to counteract the upward pressure exerted by the spring underneath the space bar by adding weight to the bar itself. So I sellotaped two magnets I had handy to the bar and, voilà, a much lighter typing experience:

Image

Obviously, there are a few disadvantages. This solution is not very attractive aesthetically (but then I rarely look at the keyboard itself). Also, due to their shape the magnets do occasionally get in the way a bit. And, finally - as well as most importantly - the magnets are a tad too heavy. Occasionally, the space bar hangs after I've pressed it. Each magnet weighs 20 grams; 15-17.5 grams (with a total weight of 30 to 35 grams) would likely be better for the purpose I am now using these for.

If I can find something with a better size and shape (as well as weight) I will try taping that to the spacebar, but for the time being I think these magnets are going to stay.

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fohat
Elder Messenger

01 Oct 2016, 15:08

Good idea.

A long narrow metal bar of the same size as the spacebar could be taped on for a completely reversible ballast.

Cattus_D

01 Oct 2016, 16:07

fohat wrote: Good idea.

A long narrow metal bar of the same size as the spacebar could be taped on for a completely reversible ballast.
Thanks. Using a strip that could be taped to the spacebar has occurred to me, too. As soon as I have a bit of time on my hands I'll look into options - ideally, I'd find a workshop where they could make one for me with exactly the right dimensions. :-)

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Laser
emacs -nw

01 Oct 2016, 16:33

If possible, one should add such a weight *inside* the spacebar, to make it invisible :) Plastic in-fill?

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fohat
Elder Messenger

01 Oct 2016, 17:02

Laser wrote:
If possible, one should add such a weight *inside* the spacebar, to make it invisible :) Plastic in-fill?
Removing and replacing Model F XT and AT space bars is a mammoth undertaking.

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Laser
emacs -nw

01 Oct 2016, 17:31

Ah yes - I was thinking at something more like using some sort of syringe to pour hot plastic inside the spacebar, while the whole keyboard is upside down; probably not easily doable, though.

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ohaimark
Kingpin

01 Oct 2016, 18:53

Option 1: Modular
Hammer some fishing sinkers flat or find some flat weights that will fit inside the spacebar without interfering with moving parts (the bottom or side walls would work).
Put some double sided tape on them.
Using a pair of hemostats, or whatever other tools prove adequate, attach them to the inside of the space bar.
Multiple weights distributed across its length may be necessary.

Option 2: Less Modular + Vibration Damping
Get some Dynamat (a sound dampener for cars made from heavy, sticky tar mats) and layer it on the inside of the space bar with whatever tools are convenient.

Option 3: Permanent
Remove the case.
Place the keyboard upside down at an angle that allows spacebar access.
Whip up some slow curing epoxy.
Mix some small ball bearings into said epoxy.
Suck the epoxy into some medical tubing wide enough to accommodate the ball bearings, perhaps using a syringe for suction and pressure.
Bend the tubing so it goes into the spacebar.
Extrude the epoxy/ball bearings into the space bar without getting it on or in the way of any moving parts.

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