by DarkTerritory » Fri Mar 04, 2011 10:14 am
Bob,
For cementing the ballast down I'm going to use something a good friend of mine found that seems to work great for ballast and many other applications where matte medium would normally be used. It's a product from a company called Laticrete and it's called "Mega Bond Additive". It's a product intended to be mixed with thinset mortar for installing tiles on walls that need to be impervious to water. It is about the same watery appearance and consistency as matte medium to apply and bonds very well - but the amazing thing about it is that unlike matte medium when it sets it is flexible and resilient! You can actually press down on your ballast with your finger and it will give a little, meaning it won't chip if a tool hits it. Since it's a type of latex, it's also great to cut down the transference of vibration / sound to your subroadbed, so your track is quieter. You won't end up with any white residue like you can with matte medium. It's available at Lowes and Home Depot, and perhaps best of all, it's considerably less expensive than matte medium!
I was skeptical about it at first but I helped him ballast a small yard with it a few months ago and it worked amazingly well. I'm convinced. He uses it everywhere you'd normally use matte medium to great effect.