Vacuum Brakes On Steam Locos

These just feel completely wrong in SoS (I don't own Peak Forest but imagine they're the same), and have ever since TSW2. I don't have fine control over the brake pipe pressure like I would with a Victory Works or Bossman loco in TSC, and there's bizarre behaviour like being able to increase brake pipe pressure by moving the brake handle into release even with both ejectors closed and the loco stopped. Am I missing something or is the brake simulation just borked, like most other aspects of the steam simulation?

 

Im not sure. It might just be accurate..

 

I don't see how the existence of slow speed collisions is relevant to my point.

 

No I'd say its probably a little more accurate than in TS1, the bouncing back is likely the fact when you apply the vacuum brake it lets air into the pipe at the front rapidly drops the vacuum there, but at the back it takes a while for air to reach it it and start to drop. When you stop letting air into the pipe, the pressure along the pipe has to equalise, as such the front the vacuum will rise while at the rear the vacuum drops.

This occurs in air brakes too, indeed before the use of equalising reservoirs in the brake valve it used to be quite a major problem. When the brake was applied the front pressure rapidly dropped naturally causing the brakes to apply there. However when the brake valve was moved to lap air ceased being let out of the pipe and so the pressure begins to equalise along the brake pipe, this however on triple valves triggers a brake release as soon as the pressure starts to rise at the front causing the brakes at the front to release. The fitting of equalising reservoirs prevents this by controlling the pressure the air drops down to and stops it rising back up. A tangent I know but illustrates the point.

 

Doing some experimentation I think you're right. Well, that's one mystery solved.

 

Oh. I thought you were after fine brake control..
Not to worry. I'll crawl back under my rock.

 

The earlier systems did not have any capability to set vacuum brakes at a fixed position, so either you applied them or you released them. The normal operation is to apply and release in sequence and repeat the sequence as many times as needed. However you can still manage to have some kind of partial aplication by using brake application in combination with small ejector. But this is not really precise and I find easier to apply and release when reaching the desired level. On the 50s they started to implement vacuum systems that allowed such partial application.

Cheers