Just to finish off a couple of things about chain tensioning - things which many people forget to mention, but that have a huge impact on how loose, or tight, your chain is. Find out more after the jump...
If you have just adjusted your chain after carrying out some maintenance then your chain should be set correctly based on the information in the last post "Chain Tensioning...".
But what if you've just been cutting some timber and realised that the chain is a little loose? If you're not careful, this is where some of the problems can creep in.
Obviously, as you've been cutting a certain amount of heat is generated (that's one of those understatements - a lot of heat is generated!). As I'm sure you are aware, when something heats up it expands, then when it cools it contracts.
Now I'm pretty sure that you are ahead of me here - if you've been merrily cutting wood for the last ten minutes, that bar and chain will have heated up nicely and the chain will have expanded. That expansion makes the chain appear looser than it was when the saw was cold. And here is where the problems can occur.
If you were to adjust the chain tension whilst it was hot (quite apart from burning your hands whilst you held the bar nose up), you'd find that as it cooled down the chain would shrink and tighten up around the bar. The chain tension would now be way too tight.
To solve this problem, always let the chain and bar cool down first, before you adjust the tension - it's a good excuse to grab a cuppa while you wait.