18 replies to this topic

[Dmitri Valenov]

So I put together a build for my Commando and decided to see what would happen if I upgraded to double heat sinks. Low and behold the heat efficiency shot up to an ungodly level even after it removed the three heat sinks I currently had. So then I go to save the configuration and a message pops up saying that I need to have 3 heatsinks to run the mech.

Really? Why do I have to waste 10% of my mech's weight on equipment that I don't need. It seems a little absurd.

Automatic heat dissipation should already be built in to the engine itself so wouldn't it be better to just raise the tonnage of the engine by 3 tons and remove the heat sink requirement. This would make those of us who use 3rd party sites to theorycraft our mechs before we pay for them much happier in the long run as we wouldn't have factor in whatever nebulous restrictions are tied to our engine.

Dmitri

[Havyek]

No offense, but if your 3rd party MechLab doesn't have the correct information and requirements in it, you need to find a better 3rd party MechLab.

http://mwo.smurfy-net.de/mechlab

AFAIK this one pulls its information from the game's XML files, so that when patches are introduced, the MechLab updates their new values.

It'll also show blue/red when you have sufficient/insufficient number of heatsinks on a build.

[UraniumOverdose]

Because they changed the system, normally you should get 10 sinks with an engine. I believe engines lower than 250 had their weight reduced, the weight gains come back when you add the minimum number of sinks. It was to balance out people taking slower engines and not losing crit space for the sinks I think.

[Dmitri Valenov]

I was using smurfy's mechlab, just didn't notice the red around the number of heatsinks. I blame my color blindness.

[wanderer]

Yep. Canonically, 'Mechs have 10 heat sinks minimum- in fact, it actually represents the cooling system that comes with the engine. Smaller engine packages that don't "come" with 10 in MWO get a weight discount that you have to install the appropriate number of sinks into the 'Mech ala carte to bring it up to what the 'Mech has to have.

This is because at idle and with maximum engine damage in-canon, a 'Mech generates...an extra 10 waste heat per turn, meaning that even a critically damaged engine can always be at least idled without melting the 'Mech in the process. Safety first!

[pesco]

The requirement on number of external heatsinks is per BattleTech rules.
It may be a little confusing here because MWO doesn't show the free in-engine heatsinks, but it goes like this:

Every Mech has 10 so-called engine heat sinks (single or double).
The weight of these heat sinks is always free.
For every 25 points of engine rating, you can put one heat sink in the engine

So with e.g. a 250 engine, exactly the 10 engine HS go into the engine.
With larger engines you get additional heat sink slots in the engine (MWO will show this).
With smaller engines, you have to place the extra engine HS outside.

[Majukey]

I made myself a dual guass cataphract the other night. I only had 8 mounted/slotted heatsinks on the engine so I had to add another DHS to each of the side torsos to reach 10.

Now the mech's heat efficiency is 4.3 or slightly higher..

Seemed a bit daft, would have prefered another 2 tons of ammo, but pff... these things happen.

[Redshift2k5]

You are not wasting any of your mech's weight. The weight of heatsinks up to the 10 minimum, is included in the tonnage for your engine.

I imagine this was an easier system to code (flat-rate discount on the engine plus normally-weighted heatsinks) than having a HEAVIER engine with magic weightless heatsinks until you reached the minimum of 10.

Suffice to say it is only costing you additional slots, not tonnage.

[Tickdoff Tank]

Majukey, on 11 February 2013 - 12:16 PM, said:

I made myself a dual guass cataphract the other night. I only had 8 mounted/slotted heatsinks on the engine so I had to add another DHS to each of the side torsos to reach 10.

Now the mech's heat efficiency is 4.3 or slightly higher..

Seemed a bit daft, would have prefered another 2 tons of ammo, but pff... these things happen.

Have you considered switching to SHS instead of DHS? Depending on the additional armament you can save a bit of sapce and might still be fine with the heat.

[Rakashan]

Redshift2k5, on 11 February 2013 - 12:25 PM, said:

You are not wasting any of your mech's weight. The weight of heatsinks up to the 10 minimum, is included in the tonnage for your engine.

I imagine this was an easier system to code (flat-rate discount on the engine plus normally-weighted heatsinks) than having a HEAVIER engine with magic weightless heatsinks until you reached the minimum of 10.

Suffice to say it is only costing you additional slots, not tonnage.

That's not true because of the way they chose to code and handle the math in MWO. It's why the numbers on engines in MWO don't match those of TT. They implemented the same system but because they wanted the 10th heatsink and the 11th heatsink to use the same code, every heatsink above Engine_Size/25 costs weight in the MWO implimentation. The Engines smaller than 250, however, are lighter in MWO than TT so that Engine + Required Heatsinks from MWO == Engine in TT.

For engines at 275 and larger, the math is still skewed to cover gyros but it no longer gets fudged for heatsinks. Instead, you get slots for heatsinks in the engine which obviously take no space but do continue to add weight.

[Josef Nader]

In TT, you got 10 sinks for free. If your engine was too small to mount 10 inside (i.e. smaller than a 250) you mounted them outside your engine at the cost of critical space for zero tonnage. As the people here have said, it's not very clear in MWO, but the engines under 250 have had their weight reduced to allow for the free tonnage. Confusing? Yes. Sticking to the rules? Also yes.

[Majukey]

Tickdoff Tank, on 11 February 2013 - 12:33 PM, said:

Have you considered switching to SHS instead of DHS? Depending on the additional armament you can save a bit of sapce and might still be fine with the heat.

I'm at the weight cap on the mech and still have a good few crit spaces to spare, so it wouldn't help sadly.

I've installed two medium lasers on it now, but the heat efficiency is still comically high.

[MustrumRidcully]

The funny thing is - "lighter engines are too small, so you need to spend extra crits on heat sinks outside the engine" - but all engines of the same class (Standard, XL or Light) need the same number of crits!

[Corvus Antaka]

Hopefully PGI will adjust the heatsink requirement so that half the engines are no longer useless.

[Fooooo]

The commando is the main gripe I had with the way they changed the system.

I used to be able to go 3srm6 with 8 HS.

I was hoping to do exactly the same, but with DHS, which would mean more than 2 alphas before I shutdown. (not that its the most effective build for a commando right now, but I like having fun with it.)

Basically I can't do that now, which does annoy me, however after reading over the rules a while ago and other people posting pretty much the same reasons as people have here, I sorta gave up hope of it changing.......

[Taizan]

Moving this topic to the Guides sub forum, where it is more appropriate.

[John MatriX82]

Just remind to employ (when is possible of course) engine ratings that can be divided by 25.

Therefore the best engine rating is 250, since it offers 10 heatsinks within the engine without taking up any more critical slots if they are enough to run your build. Anything below will require to add 1 or more heatsinks outside that will occupy critical slots. so a 225 will require 1 external hs, a 200 two and so on.

Anything above can store one further hs or DHS within a slot inside the engine. A 275 allows to add 1 more heatsink inside the engine, a 300 two HS, 325 three, 350 four and so on.

Please also notice that DHS provided by the engine have a cooling efficiency of 2x. Anything you add outside will work at 1,4x efficiency.
Therefore a 250 rating engine will bring in 10 DHS working at 2.0, while a 225, will bring 9 working at 2x and the one that you'll have to add outside will work at 1,4x efficiency. Only the first 10 DHS will work at 2x. So in a 300 rated engine with 12 total DHS, the first 10 will work at 2x, the two added inside the engine slots will keep working at 1,4x.

[Snib]

MustrumRidcully, on 12 February 2013 - 02:53 AM, said:

The funny thing is - "lighter engines are too small, so you need to spend extra crits on heat sinks outside the engine" - but all engines of the same class (Standard, XL or Light) need the same number of crits!

Your car doesn't come with a bigger or smaller engine compartment either if you buy it with a another engine.

[qki]

A full explanation:


As per the Battletech rules, every mech needs a cockpit (3 tons), and a gyro (engine rating/100, rounded up). A number of heatsinks equal to engine rating/25 can be mounted inside the engine.

Every mech comes with 10 "free" heatsinks, though if the engine rating is lower than 250, some of the free sinks have to be placed in the regular critical slots.
Since MWO has no way to distinguish between the free, and regular heatsinks, engines smaller than 250, have their weight reduced to compensate.

Also the gyro, and the cockpit are added to the engine weight, so the final formula looks like this:

MWO angine weight = battletech engine weight + gyro + 3 tons(cockpit) - X, where X is the number of heatsinks that don't fit inside out of the initial 10.