If you've read the entire thread and seen other posts by SpiceBar he has said it reduces travel..in fact, he needed to iron it down to keep the switch from actuating all the time..which is a significant amount of reduced travel...It also means it is already pushing on the dome. It most definitely changes the feel.
Could you please quote where he said this? I didn't see this on the second time of reading just now.
And he recommends in any case to iron down the pads for the mod to preserve the feel of topre. And again he said on his leopold that even without ironing it retains the true feel of topre.
I would indeed recommend the ironing method. It's a bit more of work, but from my experience the slimmed landing pads do a better job of preserving the feel of the Topre switches and the sound dampening on the upstroke is exactly the same (compared to a non-ironed landing pad).
Once ironed as I did, the width of the landing pad is slightly more than 0.5mm. The original landing pad is closer to 1mm. The half millimeter you are saving makes a small difference in feel, and reduces the risk that a key stay always actuated (which is my case happened only once out of 88 keys and was easily fixed).
He doesn't say it preserves the original feel....there is another thread (I'm not going to search for it) where he talks about the travel reduction..it is definitely there...It is actually impossible for it NOT to be there. The type S Topre switches have a longer slider...in the regular switch you are putting something that blocks the slider from going all the way up..it will reduce how far it moves...
The difference between this type of mod and a Cherry MX o-ring mod is the Cherry MX dampens on the way down and reduces the bottom portion. The slider comes all the way back up. In the Topre mod, it goes all the way down but it doesn't come all the way up. I'm sure you know that already. So knowing that already and knowing you put something that prevents the plunger going all the way up, you're going to reduce travel. You're going to partially push down the rubber dome already. The fact that he's already talking about actuation getting stuck shows this as well...
Does it really matter? Depends on each person. Some people will prefer it this way..some won't. Some people prefer huge o-rings on Cherry MX so the travel is reduced heavily...and some don't.
I think I need to clarify. It's too bad I have never found the time to properly document the RF87U mod.
The first Topre landing pad mod I did was on a FC660C and on a RF88. The important difference from the 87U is that they have higher actuation forces. I'm not sure if the force comes from stiffer domes or stronger coiled springs. Anyway, they are 45g while the RF87U goes down to 30g on some keys.
The problems I had with key staying actuated or almost actuated where rare on the FC660C and the RF88U. That's the first time I had the idea to iron the landing pads. I had to iron just 2 or 3 for the two keyboards (I don't remember exactly how many for which, it may have been 2 for the FC660C and one or maybe even none for the RF88).
On the RF87U, I did not even try the non-ironed landing pads. I know it would have been too risky and that it would have failed on some 30g keys.
The great thing with landing pads is that you can iron them to death. You can easily make them 0.3mm if you want. After a few trials I have settled on approximately 0.5mm, or half their original width. You must also take into account that the landing pads are slighly compressed by the dome and the spring once they are in place, so they may be even slightly thinner.
My goal was to get a really silent RF87U, and I think I have shown that it was a success. With thinner landing pads, I guess the noise reduction would have been less effective.
Non-ironed landing pads in the FC660C and RF88 affect the feel a little bit. The dome is already slightly compressed, so when you press a key you feel less of the dome's collapse. They feel very slightly more linear. I'm pretty sure I could have preserved the original feel with ironed landing pads, but I like these keyboards as they are now.
The RF87U is a slightly different story. It feels a little too much linear now. It's not a problem for me, I just love the keyboard.
But I would certainly advise to try to iron the landing pads to make them 0.3mm of even a little bit less in width if possible if you want to preserve the feel as much as possible.
I don't think that doing the mod is just for fun. I have an HHKB Type-S, and I can tell you it's nowhere near as silent as the RF87U. The mod produces a keyboard that is much more silent than a Type-S. The "Thock" is still there, but someone in the same room could as well not notice that you are typing. The Type-S is very far from this.
If I manage to get some free time, I may even try to silence half of my HHKB Type-S just to show you what I mean. Some owners of the $400 Type-S may die of heart attack!
On the other hand I understand that not everybody needs such a silent keyboard. I do, because at night I work in a room where I have my pregnant girlfriend and our 2.5yo sleeping nearby. So for me it was very important. But I must concede it's a lot of work: 4 to 6h for a Realforce.
