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ALPS spring surgery

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lowpoly:
Thanks. :)

Chloe:
I did some activation force measurements using 1p coins and kitchen scales. These measurements are approximate. I've decided to do the whole keyboard as this will give me an idea of whether I will like the red Cherries as they activate at 45 15 cN, but begin at 30 cN. Cherry browns begin at 40 cN. The initial resistance feels lighter in the spring shortened ALPS.

The unmodified cream ALPS - 62 cN.
Cherry MX browns - 42 cN (the datasheet says it's 45 20 cN).
Cream ALPS with spring shortened #1 (see picture in first post) - 40 cN.

I have just tried shortening only a little from the spring and got 60 cN:

Chloe:
I've just finished putting the keycaps back on the keyboard. It feels so fast now! It's much better than it was before. I didn't really like the feel of the switches as they were.

The only thing I notice now is the shorter key travel.  With the switches being so light it is hard not to bottom out. I think I will prefer the red Cherries because MX switches have longer key travel.

It's taken 2.5 hours to shorten the springs in all the switches. I found it better to do the tasks in steps, working through the keyboard row by row.

Step 1
With the keycaps removed, remove the upper housing and stem from switch. It's possible to do it in such a way that the leaf stays in the upper housing as you remove it. I think if you push the stem towards the switch mechanism it will hold the leaf.

Step 2
Remove springs and trim them. Then replace them in the switch lower housing.

Step 3
Push the stem as far down as you can in the upper housing without the leaf falling out. This helps ensure the spring will fit back into the stem. Place the upper housing over the lower housing and push quickly.  Now test the switch, if it feels like the stem won't go all the way down or the switch is making a scrunching sound you need to open the switch and try again.

I found that if you shorten the springs too much, the spring might not fit into the stem and this can cause problems with the stem not returning as it should. I solved this by stretched the spring out so it fits. It feels the same. I don't think you can go much shorter than I have without having to stretch the spring to make sure it fits into the stem.

wellington1869:
thats a great mod, switch kitten ;)

sandy55:
For shortening surgery ( to make it total length for 60cN ), I recommend you to trim 2 turns from the top and 1 turn from the bottom, or 3 turns from the top  keeping last 1 turn in the upper portion of winding with no gaps ( hope you understand what I want to say ).   I would rather trim only 2 turns from the top.

Chloe, You are a good surgeon,and at the same time, an excellent analyst like Ms. O'Brian.

Seems like SGI900829 ( non AT compatible ) uses a shorter spring.
see the bottom of this page.

Also Focus FK-2001 ( real alps/white ) has similar spring.
see attached picture.
from left
Focus FK-2001___10mm
Silitekc WIN______11mm
Acer KB-101A____ 11mm
Omni 102________11.3mm

sandy55

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