Bolt mod, sanded the moons!

[65a]

So I have a Unicomp Endurapro. It worked great until I moved.
I noticed it was rattling, so I took off the outer casing, and lots of small plastic disks fell out... :/

Long story short, I realized it needed a bolt mod.

After glancing at the Geekhack wiki, I busted out a dremel and 1/16 drill bit.
I used the globe sander dremel attachment to basically make all the rivet studs flat, then drilled holes at the former studs with the 1/16.
All of this went fairly well (all holes align except one).

However, this morning I glanced at some other resources, which mention small crescent moons which shouldn't have been sanded.
Unfortunately, mine are almost all gone.

Can I make up the removed gap with additional washers? What role do these play, and why is removing them bad?

[fohat.digs]

If you sanded every one consistently, you may be OK. You do have some room to play with how you tighten the nuts.

I do not have any abrasives of any kind in my M-modding kit. if you use a sharp fresh chisel blade in your exacto knife, you can top the rivet shafts to a beautiful clean mesa-like top surface. I leave them as long as I can, they always went through the holes anyway.

And yes, there is an extra hole near the center that drives us all crazy.

[Grr8]

However, this morning I glanced at some other resources, which mention small crescent moons which shouldn't have been sanded.
Unfortunately, mine are almost all gone.

I've done a bolt mod and avoided removing the crescent moon - I used a scraper/razor blade to cut off the stumps of the rivets.

I followed this guide mostly:

However, this morning I glanced at some other resources, which mention small crescent moons which shouldn't have been sanded.
Unfortunately, mine are almost all gone.

I've done a bolt mod and avoided removing the crescent moon - I used a scraper/razor blade to cut off the stumps of the rivets.

However, are the crescent moons necessary?

What really is their function? Anyone can explain it?

However, this morning I glanced at some other resources, which mention small crescent moons which shouldn't have been sanded.
Unfortunately, mine are almost all gone.

I've done a bolt mod and avoided removing the crescent moon - I used a scraper/razor blade to cut off the stumps of the rivets.

I mostly followed this guide:

http://forums.overclockers.com.au/showthread.php?t=1024488

with some tips from phosphorglow's video on YouTube:

http://m.youtube.com/watch?v=7JkO35gsIB8


However, are the crescent moons necessary?

What really is their function? Can anyone explain it?

[fohat.digs]

However, are the crescent moons necessary?

What really is their function? Can anyone explain it?

I always assumed that they were there to keep the tolerance between plates "just right" because gaps and spaces make a big difference in how the spring hammers feel and react.

If you grind them off, it would bring the plastic and metal plates closer together. There are a few layers of mylar and rubber in there, I wondered whether their thickness approximates the thickness of that stack of membranes.

[65a]

I think they are there for tolerance, that is why I'm thinking of sanding flat and using a washer or two to approximate the spacing. Everything I have read that referred to not sanding these states that removing them "ruins the feel" of the keyboard, which would imply to me that the spacing is critical for the hammers?

[fohat.digs]

If they are the only points of contact, then there is a very delicate float to it.

Washers would dramatically increase the surface area, perhaps very thin paper or plastic washers would be preferable to metal.

[mkawa]

the moons are there to keep tolerances, but nylon washers work fine as well. the reason you need a gap reinforcement between the barrel plate and the back plate is because when a button is hit, the plastic tends to deform toward the backplate from the pressure of both the finger and the hammer. enough slamming on the board and the gussets that are used globally to maintain clearance between the two plates will not be able to hold that clearance across the board.

[berserkfan]

the moons are there to keep tolerances, but nylon washers work fine as well. the reason you need a gap reinforcement between the barrel plate and the back plate is because when a button is hit, the plastic tends to deform toward the backplate from the pressure of both the finger and the hammer. enough slamming on the board and the gussets that are used globally to maintain clearance between the two plates will not be able to hold that clearance across the board.

I am interested in doing bolt modding now, and if anyone can explain why washers are important, please do. I quite fail to understand this. In fact, I am so uneducated in mechanical things, I don't even understand what washers are for in general. Isn't a nut and a bolt enough for general mechanical robustness?

[fohat.digs]

the moons are there to keep tolerances, but nylon washers work fine as well. the reason you need a gap reinforcement between the barrel plate and the back plate is because when a button is hit, the plastic tends to deform toward the backplate from the pressure of both the finger and the hammer. enough slamming on the board and the gussets that are used globally to maintain clearance between the two plates will not be able to hold that clearance across the board.

I am interested in doing bolt modding now, and if anyone can explain why washers are important, please do. I quite fail to understand this. In fact, I am so uneducated in mechanical things, I don't even understand what washers are for in general. Isn't a nut and a bolt enough for general mechanical robustness?

Washers spread out the pressure under a nut or bolt head and make the connection stronger and more uniform.

Here, I think they are referring to extremely thin non-metallic washers between the plates to make up for material removed by overly aggressive grinding.

I use thin washers on the back just because I like washers, but they are not needed if the holes are close to the size of the bolt shaft.

[berserkfan]

the moons are there to keep tolerances, but nylon washers work fine as well. the reason you need a gap reinforcement between the barrel plate and the back plate is because when a button is hit, the plastic tends to deform toward the backplate from the pressure of both the finger and the hammer. enough slamming on the board and the gussets that are used globally to maintain clearance between the two plates will not be able to hold that clearance across the board.

I am interested in doing bolt modding now, and if anyone can explain why washers are important, please do. I quite fail to understand this. In fact, I am so uneducated in mechanical things, I don't even understand what washers are for in general. Isn't a nut and a bolt enough for general mechanical robustness?

Washers spread out the pressure under a nut or bolt head and make the connection stronger and more uniform.

Here, I think they are referring to extremely thin non-metallic washers between the plates to make up for material removed by overly aggressive grinding.

I use thin washers on the back just because I like washers, but they are not needed if the holes are close to the size of the bolt shaft.

So washers are generally not needed, except to improve the fit in case the screw is slightly loose inside the hole? I'm thinking that if I use the same diameter bit as the screw diameter, normally a washer is not needed, right?

I remember repeatedly seeing warnings against making a bolt mod too tight. So a tight fit isn't actually ideal.

[fohat.digs]

I remember repeatedly seeing warnings against making a bolt mod too tight. So a tight fit isn't actually ideal.

In that case "tight" refers to torquing down the nuts. I hold the socket in my fingers, without the handle, and just barely make them "finger tight" but other people will go farther.

My experience is that if you crank them all down hard, the tension/compression situation in the barrel plate gets weird and some keys will not work properly.

[mkawa]

the small nubs attempt to maintain consistent clearance between the barrel plate the membranes and the backplate under stress. i would not try to put any kind of spacer between the membranes and the barrel plate. the reason why i wouldn't bother is that the nubs are made to fit _through_ the membrane holes, and further, the nubs only really work when the assembly is held together with the melt-rivets. bolting the thing together crushes the nubs pretty quickly. you are better off carefully torquing the assembly down until you feel that the key response is even and consistent across the board.

if you have torque control drivers, those are really the ideal way to torque a bolted board down. however, accurate torque control drivers are pretty expensive, and a successful bolt mod can definitely be done without them.

finally, if you end up unhappy with the result of the bolt mod, a new barrel plate from unicomp is about 10$.

[Melvang]

the small nubs attempt to maintain consistent clearance between the barrel plate the membranes and the backplate under stress. i would not try to put any kind of spacer between the membranes and the barrel plate. the reason why i wouldn't bother is that the nubs are made to fit _through_ the membrane holes, and further, the nubs only really work when the assembly is held together with the melt-rivets. bolting the thing together crushes the nubs pretty quickly. you are better off carefully torquing the assembly down until you feel that the key response is even and consistent across the board.

if you have torque control drivers, those are really the ideal way to torque a bolted board down. however, accurate torque control drivers are pretty expensive, and a successful bolt mod can definitely be done without them.

finally, if you end up unhappy with the result of the bolt mod, a new barrel plate from unicomp is about 10$.

$23 for the barrel plate. 

[mkawa]

thanks for the correction. i just realized that i've been purchasing ssk barrel plates and not full-sized M plates.