After reading a lot of MES modification threads I was inspired to build my own smoke box. I currently have no intentions to cold smoke but I wanted to increase the wood capacity/smoking time as well as make something that I could check/service/refill without opening the door (I didn't like having to find a flashlight to peer down the tube to check the chip tray). I ended up using a 4" round tin can and a dryer duct elbow. I installed a piece of screen to hold the chips off the bottom and drilled some holes for air circulation. After numerous trials (and errors) I found that it worked best when I filled it with chips and then set one lit chunk on top. I also found that it only needed one 1/4" hole in the bottom to produce enough draft. I set it on a ceramic tile to absorb the eat and then just pushed it up against the loading tube. The smoker drafted perfectly. I am getting 3 hours of smoke without messing with it, which for me is a great upgrade for the 30 minutes using the stock chip tray. Well worth the $5 investment.