There are a bunch of steam achievements that require to have, i believe 5 at the most, friends for certain achievements to be unlocked, on the part of even having friends and that play tf2 and care about achievements well that's a tough search. Or even help out on the non friends achievements like a medic with a uberladung helping the others out.
So anyone else care about wanting those achievements and perhaps pick a certain day in which we can do some of them together?

Perhaps also add a time when it suits you best to play, perhaps in the weekend or evening, so we can pick a time when we all can.

[EDIT]
From what i gather these 6 are required to have atleast friends participating in your list, one being 7 people.

General
With Friends Like these...
Play a game with 7 or more players from your friends list. (so 7 plus yourself i think, making 8 in total)
Difficulty: Hard
How to: This is one of the rarest achievements among players as shown by Valve statistics, due to the fact it almost never occurs incidentally in public rooms. Try joining a clan of regular players or organizing this achievement with a group of people online. Alternatively, enable Steam community features ingame and add everyone already on the server to your friends during a game, and you'll get the achievement when the map finishes.
Note- You must play a full round with all 7 players remaining for the duration to unlock this achievement

Medic
Family Practice
ÜberCharge 5 of your Steam Community Friends.
Difficulty: Easy
How to obtain: Join a game where a friend is currently playing and deploy an ÜberCharge on him.
You must charge five different friends for this achievement, so charging the same friend several times will not work.

House Call
Join a game that one of your friends is in and then deploy an ÜberCharge on him.
Difficulty: Easy
How to obtain: Use the "Join Game" option from the Friends window in the Steam Community program.
After joining, do not die before deploying the ÜberCharge on your friend. If a server changes maps, the system will count you as joining a friend's game.

Soldier
Banner of Brothers
Buff 5 Steam friends at once with the Buff Banner.
Difficulty: Medium-Hard
How to obtain: Find a group of friends you regularly play with and stick together in firefights. After a victory, use the Buff Banner in the enemy spawn, allowing you to buff all of your teammates, as everyone is usually grouping there after rounds.
This achievement can be accomplished by using the Battalion's Backup or Concheror instead.

Doomsday
Flight Crew
Play in a game with 5 or more players from your Friends list.

Foundry
Foundry Force Five
Play in a game with 5 or more players from your Friends list.
How to obtain: After gathering a group of friends, complete one full round.

Current player list:
-Lugum - same nick on steam.
-Cich http://steamcommunity.com/id/cich_/
-Goatbrush
-Mr. Caine http://steamcommunity.com/id/MrCaine
-Brasas

For getting some of the solo achievements yourself i suggest the map achievement_pyro_final.

Could be fun.
I'll join you in this quest.

I'll help if you need an extra person, I used to like hunting for the achievements but I haven't played TF2 for years and they've added so much stuff. I'm not even sure what an uberladung is.

If the achievements are something my lack of activity/current knowledge can mess up then don't worry about it, otherwise most evenings are fine for me.

Uberladung is dutch/german, english word is ubercharge.
http://wiki.teamfortress.com/wiki/%C3%9CberCharge_strategy
The ÜberCharge is an ability of the Medic that enables himself and his healing target to become fully invulnerable to damage. ÜberCharge is built up mainly by healing teammates with the Medi Gun and has the ability to turn the tide of the battle when used offensively, and lock down the enemy team when used defensively.
Several require it, same goes for other classes needing an engineer and it's builds.
You can always play a test game before we start, to get into it again, but it isn't science that it's hard to get into.

There are several achievement servers for like killling an x amount of enemies but non seem to focus on doing stuff with friends and such.
I think we should focus on getting the friends achievements first, then later we can always look at the achievements like the ubercharge and engineering ones.
There is a wiki that fully describes on how getting the achievements when time comes i can make a list of achievements what we can do.

So 3 people so far, even if we get 5 people feel free to still enter, perhaps for other achievements, be a spare or with enough a new group can always be formed.

I'm down for it.

It's no problem i guess, but i think it helps if you play atleast a bunch of rounds first as it will give you an idea on how the game works but it also gives you random item drops which can sometimes help (and in some (non friend)achievements you need certain items). :)

Edited the op to reflect the achievements and current players, one achievement needs up to 8 people playing a full round at the same time and in the same team (might be tough). So we can still use a bunch of people and with that amout perhaps a few spare.

Please note your preferred time, or certain days/hours you won't mind playing. (i think this might be an achievement on it's own) :p

I would suggest for now any saturday and potentially this saturday at 20:00 (dutch time)?

Maybe if there will become enough interest we as the people from this forum, take/claim a empty server to play on regurarly so that people help eachother at any given time but also play a friendly game if they chose to desire.

I'm OK with this Saturday at 20:00.

As for other times, it varies, let's see what others say, I can probably adapt.

Saturday at 20:00 works for me.

Saturday works for me.

Okay saturday it will be then, i hope we can get 8 people but if not we can do atleast the other achievements.
We also need eachothers steam name to add eachother, mine is lugum.

Here's mine:
http://steamcommunity.com/id/cich_/

Is your profile private? It doesn't show up in search.

Can be, though Brasas already added me without any problems.
You can also go to the friendslist and type my nick there i think.