I like doing support roles and chose the Jedi Knight as my first character because they're tanks, but I've been doing DPS so that I'm not too hold up on fighting enemies.

I then made a Consular and began with going full tank first, but I quickly found out that most of the tank abilities are meant for aggro and defending targetted players and now kinda went with more of a bruiser so that the few damaging abilities I have can do more damage.

My Jedi Knight is lvl 59 and still pure DPS. When do I start working on a tank setup once I decide to do operations?

I like doing support roles and chose the Jedi Knight as my first character because they're tanks, but I've been doing DPS so that I'm not too hold up on fighting enemies.

 

I then made a Consular and began with going full tank first, but I quickly found out that most of the tank abilities are meant for aggro and defending targetted players and now kinda went with more of a bruiser so that the few damaging abilities I have can do more damage.

 

My Jedi Knight is lvl 59 and still pure DPS. When do I start working on a tank setup once I decide to do operations?

Depends on which Jedi Knight class you picked. If you picked Sentinel, you're stuck as a DPS because all three Disciplines are DPS.

If you picked Guardian, you may have the wrong Discipline selected. I believe the correct one is "Defense". See the "Mentor" on the Fleet or Coruscant if you want to change it, or buy the "Field Respec" character perk from the Legacy panel (Y key) and change it yourself. I believe the Mentor is in the Combat Training area of the fleet, but whichever area it is, he is in one of the bays on the outer-most part of Carrick Station.

And yes, you're right, a large fraction of tank abilities are focussed on aggro / threat generation and defending other players, because that's the tank's job. DPS classes / Disciplines have the job of dealing damage, not tanks.

The classic trinity roles are:

* Tank holds the enemies' attention on himself to stop them hurting the other players. His job is NOT to kill them, although he cannot do his job without dealing *some* damage.

* Healer keeps the tank from being killed. In spare moments, helps out injured DPSes. If there's no healing needed, attacks enemies.

* DPS kills enemies. DPSes seem like they have the easy job, but they must take care to not outstrip the tank's aggro generation, and must avoid 'standing in stupid" (remaining in AoE attack markers) and similar.

Yes I know how to change my discipline and I know how support roles work. I'm simply asking at what level should I start moving on towards tank or if I should wait til I finish SoR and everything passed it first for story before moving onto the raids and such.

I'm only doing dps so that I'm not stuck fighting the same group of enemies forever and ever before moving onto the next group of enemies and fighting them forever and ever when doing the story.

The essential point to take away from what I said is that a tank spec will be slower when doing solo content because tank specs concentrate on threat management (generation) and self-defence at the expense of all-out damage rate.

That said, from what I've heard, Guardian and Juggernaut are the highest-dps tanks, so should be slowed the least.

But worry about developing your tank performance ("tanking is a support role" is a highly debatable assertion, by the way(1)) as you start getting in to group content. I'd suggest, if you haven't already done so, joining a guild that can help you.

(1) For me, support roles are things like DoT spreaders, CC-experts (the fourth member of the trinity, if you like), and similar.

Yes I know how to change my discipline and I know how support roles work. I'm simply asking at what level should I start moving on towards tank or if I should wait til I finish SoR and everything passed it first for story before moving onto the raids and such.

I don't do OPS, so take this with a grain of salt:

I believe you can't join an OPS till L50. At least according to the following (and he recommends holding off till 60. That was when game went to 65).

http://vulkk.com/2016/01/26/swtor-basics-a-new-players-guide-to-gearing-for-operations/

But I think your team would expect you to be experienced with tanking in your class. So, I'd suggest getting that Legacy respec, and maybe practicing in Flashpoints. And the Guild suggestion is also a solid one (sounds like game isn't too friendly to newbs in pick up Ops?)

Or post same in Ops / Guilds forums?