Fix typo in catalyst.

Fix flamethrower crafting recipe (now only use 1 rod, calls checkparts() to set up the weldingtool and igniter).
Fix lack of message when trying to turn on an unsecured welding tool.
Fix lack of icon update when clicking plasma tank with empty flamethrower.

code/game/objects/items/weapons/flamethrower.dm

@@ -157,6 +157,10 @@
 	update_icon()
 	return
 
+/obj/item/weapon/flamethrower/CheckParts()
+	weldtool = locate(/obj/item/weapon/weldingtool) in contents
+	igniter = locate(/obj/item/device/assembly/igniter) in contents
+	update_icon()
 
 //Called from turf.dm turf/dblclick
 /obj/item/weapon/flamethrower/proc/flame_turf(turflist)
@@ -195,10 +199,6 @@
 
 /obj/item/weapon/flamethrower/full/New(var/loc)
 	..()
-	for(var/obj/item/weapon/weldingtool/W in src)
-		weldtool = W
-	for(var/obj/item/device/assembly/igniter/I in src)
-		igniter = I
 	if(!weldtool)
 		weldtool = new /obj/item/weapon/weldingtool(src)
 	weldtool.status = 0
@@ -211,4 +211,4 @@
 /obj/item/weapon/flamethrower/full/tank/New(var/loc)
 	..()
 	ptank = new /obj/item/weapon/tank/internals/plasma/full(src)
-	update_icon()
+	update_icon()

code/game/objects/items/weapons/tanks/tank_types.dm

@@ -96,6 +96,7 @@
 		F.ptank = src
 		user.unEquip(src)
 		src.loc = F
+		F.update_icon()
 	return
 
 /obj/item/weapon/tank/internals/plasma/full/New()

code/game/objects/items/weapons/tools.dm

@@ -308,6 +308,7 @@
 //Toggles the welder off and on
 /obj/item/weapon/weldingtool/proc/toggle(mob/user, message = 0)
 	if(!status)
+		user << "<span class='notice'>[src] can't be turned on while unsecured.</span>"
 		return
 	welding = !welding
 	if(welding)