still in use commercially....

[maple_leaf_eh]

Don't write off the entire class of vehicle as completely "home made", but rather serial factory built examples depending on supply and demand.

From what I've seen, the Madill Company did a lot of adapting to suit their customers. If the logging companies in BC needed a chassis that could climb 10% slopes with a 50' mast and a 30ton winch, that is what the engineering department drew. I have snaps of chassis used for open pit mine drag lines that had 4 suspension stations. Likewise, there are shots of shortened chassis with only 2 stations for increased mobility.

Madill went bankrupt a few years ago, and resurrected as a parts and tech support company owned by someone else. I don't think anyone is making new spar yarders in this economy. Several factors may be at play. The US housing market is really slow, so they aren't buying Canadian logs. Maybe every marketable big log has been cut, which I find hard to believe. Maybe the cut blocks are restrictive enough to use other recovery methods. Or, the economics are right for selective heli-logging. Don't know.