I think i've crafted enough useless weapons to make this guide.
1. The widowmaker.
+Looks awesome
+Sounds awesome
+Can one-shot almost anything
-You need to be fucking amazing to hit anything
-Takes 1/4 of your metal per shot
-Actually, totally fucking useless
-Hard crafting recipe
Final thoughts: Dont ever craft this POS.
My personal recommendation: MINI TURRETS
2. Short Circuit
-Takes too much metal to fire
-Does no DMG
-Totally useless
-Takes a ton of resources to craft
Final thoughts: Valve.. Srsly?
My personal recommendation: MORE MINI TURRETS
3. Cow mangler 5000
+Takes NO ammo
+5 shots
+Epic Alt-fire
-No DMG to turrets
-SLLLLLLLLLLLOOOOOOOOWWWWW Reload speed
Final thoughts: Don't waste your black box on this.
My personal recommendation: Black box
4. Righteous bison
+NICE damage if used right
+Can oneshot 2 snipers if lucky
+Unlimited range
+Takes no ammo
-Slow projectile speed (Almost impossible to kill scouts, thats why i rather use basic shotgun)
Final thoughts: Its all about playing style, if you rather rocket jump to the middle, rather use shotgun for scouts but if you enjoy spamming C mangler alt-fire's from the back of the map, you can use this if you feel that mangler is not powerful enough.
My personal recommendation: Shotgun
5. Degreaser
+Lightning fast weapon switch speed
+Epic with axtinguisher/mailbox
-Low damage compared to backburner
Final thoughts: If you like flanking and actual damage, backburner an better option, but if you master the skill of axtinguishing, this is extremely deadly.
My personal recommendation: Backburner
6. Detonator
+Not WORSE than flare gun
-The detonation function is near useless
Final thoughts: Keep your scrap's to yourself
My personal recommendation: Shotgun
7. Tomislav
+EPIC ''spin''-time
+Nearly same dmg as normal stock minigun
+Silent
+Faster walk speed when ''spinning''
-Heavy weapon

Final thoughts: If you have any interest having fun playing Heavy, you NEED to get this
My personal recommendation: Tomislav
8. Crusader's Crossbow
+Long(er) range
+Can heal team-mates
-The heal is same as nothing
-No noticeable damage
-Slow firing speed
Final thoughts: Keep your huntsman for Sydney sleeper, its amazing.
My personal recommendation: Blutsauger
9. Blutsauger
+Epic lifesteal
+If you can aim, you can be an actually useful battle-medic
+Firing speed
-/+ Ghost passive which is not there
Final thoughts: If you want to play medic, you need this.
My personal recommendation: Blutsauger
10. And finally, Sharpened Volcano Fragment
+Looks epic
+Lights ppl on fire on hit.
+Epic combo with a friend in Melee only servers (SVF + Axtinguisher = Ownage)
-Lower on-hit damage
Final thoughts: Everyone's personal preference, if you like oneshotting heavies, use axtinguisher, if you want to pwn spies, use this. For everything in the between, use the basic axe.
-Saimpro