by waaytoomuchintothis » Fri Nov 04, 2016 12:20 am
Moisture is the key. Where I live, there is a 5 month stretch every year when MDF needs protection. Normally, paint is enough, and I firmly recommend it. Depending on where you live and how the track is housed, what Harry and others are saying is gospel, but it is critical. Get 1/2 inch damp for just a few days, and the clock starts ticking. I can't tell you how disappointing it is to watch a track that is just fine slowly start to develop sags between supports over just a few years. As I say, if it is flat, it just won't mess up, but the liability of a damp environment is amazing. Protect your investment by taking the time to thoroughly paint all surfaces with a paint that resists moisture, and that includes the slot itself.
Under no circumstances let any of this put you off building your track! Just resist getting in hurry and seal every surface. You'll be fine, and if you live where there is very high humidity part of the year, avoid elevated sections that aren't enclosed. HRW is full of great documentation about building tracks. And you must know by now that HRW is loaded with advisors for any of this stuff.