[The Wyrm Ouroboros]

If I remember the fluff from past editions correctly, all bone lacing is done with the help of nanites, who cover your bones with a coating of your chosen material.
So it's not quite like the Wolverine - there aren't any titanium rods bolted onto your tibia, that you could engrave and carve to create your focus. :-)

Nanotech is out now, however, so they're doing it the old fashioned way, however that was. 

Oh, it was still nanotech - just a 'non-self-directing' sort of nanotech.  They were carriers, sensitive to certain magnetic field fluctuations, not pre-programmed to turn left at Albuquerque the way they are 'now'.

[Lucean]

Not possible. Leaving aside how Monofilament Whips aren't on the list of implant weapons, Fingertip Compartments can only contain micro-sized items, and a monofilament whip is definitely bigger than that.

Actually...

One popular trick is to use a fingertip compartment to hold a monofilament whip (p. 422), with the fingertip acting as control weight. Extending a monofilament whip from a fingertip compartment takes a Simple Action, while spooling it back up requires one Complex Action. There’s no telling how many actions it will take for people to stop being impressed at what just came out of your finger.

The book even says it's possible, so yeah, don't jump the gun on that one.

Edit: Not that he's even going to see this because he has me on ignore, but I guess for posterity's sake.

It's interesting. While we don't have size definitions the Monowhip has the same concealability modifier as a holdout pistol.
But this is actually the first time I see it mentioned, that the fingertip compartment wouldn't be possible to combine with the monofilament whip. Although I really like that idea

[Michael Chandra]

It's a long coil of wire, even for monofilament wire that sounds plain wrong. But I guess that when the fingertip works as the control weight, it could be possible. I did miss that part when searching the rules for the fingertip.

Is there a reason people keep bringing up their ignore status with me?_? Am I a benchmark now, are you only one of the cool kids if you manage to get on there? Do people who don't know they are still count, or are they considered wannabes because I didn't bother informing them?

[Herr Brackhaus]

The fingertip compartment source text specifically mentions hiding a monowhip in one as a "popular trick", so it seems a fair assumption that the designers intended for that to be possible. Page 455 of SR5.

[Medicineman]

The fingertip compartment source text specifically mentions hiding a monowhip in one as a "popular trick", so it seems a fair assumption that the designers intended for that to be possible. Page 455 of SR5.

a Fingertip compartment was "Shell" for a Monowhip as long as I can remember (SR2)

HougH!
Medicineman

looking down to the Post below

And yeah Michael getting put on your ignore list is turning out to be a right of passage on these forums.

Which I seem to have passed too

[adzling]

Yeah it's pretty cannon cyberpunk since one of the characters in the original collection of William Gibson cyberpunk short stories (Mirrorshades?) that started it all had one.

And yeah Michael getting put on your ignore list is turning out to be a right of passage on these forums.

[Namikaze]

Guys, a person's right to ignore people on these forums should be respected.  If being ignored is such a big deal, then make amends.  If it's not a big deal, then don't bother bringing it up.  I can't speak for Michael on this, but I know of at least two times when someone on these forums has bypassed the ignore list by either creating a new account or by using other forms of communication.  I can't speak for Michael, but the ignore list is a bit of a godsend - it prevents people from getting into unnecessary flame wars.  And I'll admit that I should use it more often with certain people that just get my goat.

Back on topic though: I think this issue had been discussed to death now.  Bone lacing cannot be used as a weapon foci at some tables, but the OPs GM might not care.  It's not specifically a weapon, so there's a greater-than-even chance that the bone lacing won't be allowed.

[Poindexter]

I don't think it's legal inside the RAW for reasons others have pointed out, but if a player had a bunch of money, the right contacts, and the sincere desire to do it, I'd let him find a way, but that's just me as a GM.

[The Wyrm Ouroboros]

... my lawyer says I should repeat that I had nothing to do with that goat, and hadn't ever even seen it before the inquest.

[Namikaze]

... my lawyer says I should repeat that I had nothing to do with that goat, and hadn't ever even seen it before the inquest.

LOL I've never understood the origins of that term, "get my goat."  It sounds...  well, you summed it up well. 

[Beaumis]

It's a long coil of wire, even for monofilament wire that sounds plain wrong. But I guess that when the fingertip works as the control weight, it could be possible. I did miss that part when searching the rules for the fingertip.

I feel this is one of those old school suspensions of disbelief things that are still there because rule of cool. Monofilament whips in fingertip compartments have been around since first edition and your guess is exactly the explanation given in the flavor text.
And technically, the coil could be tiny. The wire is two meters long and one molecule thick. Depending on how you roll it, it could take up as little as a few molecules in diameter. A mono whip is all grip and weight, the wire doesn't factor in.

Also: This

I always thought ignore lists were aptly named not only because they allow you to ignore people but also because they should be ignored in polite conversation.

Edit: Yeah got sidetracked here. Regarding the OP, according to the missions FAQ you can get basically every focus as a tattoo, which includes weapon foci and opens up a few interesting concepts. Note that they are identifiable as foci on the astral plane unless masked, so it kinda outs you as awakened but that would be true for the bone lacing as well.

[Memnoch]

Quick question about the bone foci, what about combining the bone lacing with bone spikes?

Then the bone actually would be making contact so i don't see why it wouldn't work.

[MijRai]

Quick question about the bone foci, what about combining the bone lacing with bone spikes?

Then the bone actually would be making contact so i don't see why it wouldn't work.

Bone spikes aren't in Fifth Edition at the moment.  It's iffy for 4th Ed, though.

[Marcus]

Mono-Whip is legal starting equipment as is the finger compartment, which specifically mention it and even gives actions types for deploying and retracting. There is no doubt that is legit, and both RAW and RAI. Further Mono-Weapon foci despite being an abomination in my opinion have also been seen in play. I ran across a PC with one back in 4th Missions.  Do i think that's RAI? No. But I do think it not disallowed under RAW.

[Michael Chandra]

Now I am imagining someone with a monowhip in a penile implant, and want to write a short dialogue about a guy who had one until he critglitched and took off his own balls. I hate you all.