question about best perks to put on some traps !

It always depends on what you will use them for, and ideally you should haev multiple version of every trap for different stuff. but that costs a lot of reperk.
I'm gonna list what traps you need for what missions, but if you only want to craft 1 set go for the ones you will use in general missions, since Endurance and game mode like frostnites is for true endgame players.

3x impact 2x reload speed 1x durability on floor and wall launchers for use in trap tunnels or under stairs.

4x impact 1x reload 1x durability on wall launchers for being able to knock husks over 3 tiles, usefull for knocking them over edges. Also works great for knocking husks into holes since they don't run the same reload as your floor launchers, makign it possible to use both floor and wall launchers in 1 tile.

5x impact 1x dura on floor launchers to serve as smasher killers(you only really want these in your SSD, frostnite or soloing 140 4x missions)

The durability is because there launchers fire every 5.2 seconds and you will not make it to 8 minutes without durability perks, unless you have all durability survivors and a machinist in the party.

I suggest for launchers just making both 2x reload 3x impact 1x durability. They are most usefull in general missions.

For damage traps you also have to consider if you want the most Damage per Second(dps) or the most consistent damage.

For gas traps: 2x crit damage 1x crit rating 1x reload speed 1x effect duration gives you the most damage. don't bother going 2 reload speed on these since 1 reload speed makes it stay on almost 100% of the time.

For broadsides 2x crit damage 1xcrit rating 1x reload speed gives the most DPS but considering they have a reload time of 12 seconds it's better to go 1x crit damage 1c crit rating 2x reload speed. Same for Ceiling Zappers.

Just going with damage perks instead of the crit loses you around 10% DPS, but it more consistant.

Floor spikes: 2x crot damage 2x crit rating gives you the most dps, if you put building health/second on them you can put them on the reverse stairs and make them heal themself.

for the sixth perk, Building health is the most useful in general missions against propanes building health/second is better against exploding deathburst, durability is better for SSD/frostnite.

TLDR
for general missions:

Floor Launcher[ 2x reload 3ximpact 1x durability]

Wall Launcher [2x reload 3x impact 1x durability.]

Gas trap [ 2x crit damage 1x crit rating 1x reload 1x effect duration]

Broadside&Ceiling Zapper [1x crit damage 1x crit rating 2x reload 1x health per second.]

Floor Spikes [ 2x crit rating 2x crit damage 1x health per second]

/r/FORTnITE Thread