*HOOK* Ok.
So the internal spring on a Topre switch isn't there to provide resistance, it is there for actuation, so you'd be pretty stupid to try to mess with that mechanism. You can probably try but more than likely, you'll fail. If you can find the right spring that coveys the right level of signal while changing how stiff/resistant it is, great....but probably a big fail as far as how much work to put in vs. gain.
The smart way to do what you're describing is simply use a spring like they do for the space bar...or the springs that come with NIZ/Plum which fit around the Topre slider under the keycap. This adds resistance and makes the switch feel more linear and obviously with a strong enough spring you can probably get an effect where you minimize the collapse....and you're not compromising how the switch actually actuates.
The Topre feel is because of the DOME. The collapse is 100% as a result of the dome. The spring for the switch itself plays no part in the resistance level of the switch.
I was imprecisely referring to the extra slider springs.
And how you're internalizing why the switch is heavy is wrong. All of the weight of Topre is basically "popping" the bubble you sit on. In otherwords, it requires a certain amount of force for the dome to collapse..once it does, the rest is a free fall. Have you ever seen a Topre Force Curve? If you actually use static weights you will see, the switch is not heavier than the ones you've described, you just don't understand how the mechanism works. For 45g Topre, 45g (Plus or minus a bit) is all you need for the dome to completely collapse and for you to bottom out.
What is really happening is with other switches your start up force is lower...so you have momentum. And depending on how you're measuring a switch weight, you might be looking at the weight at BOTTOM out. So lets say in a linear force graph you start off lower and get higher as the switch gets pressed further. So you combine those factors and you have a switch that might feel lighter even those it has higher peaks in actual force needed to move the switch.
There's essentially nothing contradicting to what I said. In case it was confusing I only mentioned the spring weights of some switches so you know what switch I am talking about and not that it bares any comparison between e.g. a 65g bottom out MX spring and the 45g Topre dome.
I also explained further up that the tactile event of a Topre begins pretty much from the start in a sine like wave and afterwards has a free fall essentially. For reference again:
Topre 55g:
- sine like rise from 0g up to a peak of 70g at around 1,2mm
- slow sine like drop to 55g at around 3,3mm
- Summary: hooooge but long drawn bump... smooth but very very hard not to bottom out due to the sharp rise in force that is needed to overcome the bump and the "free fall" effect that comes afterwards.
Based off of one of the Topre 55g graphs available such as:
I also know that the 62g Zealio has a much lighter initial spring force. And it doesn't change the fact that when pressed against each other slowly the the 62g Zealio pretty much bottoms out entirely before the Topre 45g compresses over its tactile bump. And it makes completely sense when looking at the force chart. The bump of the Zealio is at around 40g, while around 45g at the bottom. Just as a note: I've always felt Zeal switches to be on the lighter side just as I mentioned earlier that for me 62g and 65g Zealios are very light switches.
The 67g Zealio compresses just a little (=still lower initial spring force) but the force required for the tactile bump is now higher than that of the Topre (50g vs. 45g) and that makes the Topre bottom-out without overcoming the bump on the Zealio. Makes perfectly sense too:
With the 78g Zealio the initial spring force however is already so high that it doesn't even budge when pressed against the Topre 45g.
So tell me where there is anything wrong with my comparison on the switch weights? Where exactly have I said that the Topre is "heavier" than the ones I've described? Except maybe for the 62 and 65g Zealios which are indeed a close call and as I've already mentioned _are_ light switches?
In essence all that I was trying to say is on the contrary, that the Topre 45g is actually a "very light switch". And when pressed slowly you do indeed notice that. The force required to overcome the tactile bump is not very high. However, it's that free fall after the bump when typing quickly that leads to a hard bottoming-out that makes the typing feel heavy. The key words here are "feel" and "hard bottoming-out" when referring to Topre being "heavy".
And that's exactly what I've described earlier. To remedy this (if you don't like it - like me) I suggested the BKE ultra-light domes to reduce the tactile bump a little more if needed and paradoxically adding heavier springs to increase the force curve after the bump so in essence reducing/eliminating the "free fall". So while actually adding force (from the spring), the Topres might actually "feel" lighter to type on due to the reduction of the impact when bottoming-out.