Improving the already excellent Columbus McKinnon Primary Two Speed Tire Shredder and Columbus McKinnon Tire Chipper

The Columbus McKinnon two speed the Columbus McKinnon tire chipper are two of the major pieces of tire recycling equipment used in the United States today. They are also used in many TDF (tire derived fuel) plants and crumb rubber manufacturing facilities in the United States and around the world.

Unlimited Resources Corporation just recently finished the complete refurbishing of two Columbus McKinnon Primary Two Speed tire shredders.  And we also just recently completed the refurbishing of three Columbus McKinnon chipper tire shredders. These machines have all been modified to have hardened 4140 heat treated rotors installed in them instead of the traditional mid-steel rotors that they are shipped from the factory new with.

This has always been one of the major weaknesses of these machines since they were first built. We truly believe that this change we have made to these tire shredders will make them much more durable and help preserve the knife seats for an extended period of time if you happen to lose a knife and not replace it immediately. Of course anyone that owns a Columbus McKinnon tire shredder or chipper knows they should always shut the machines down periodically and check to make sure that all your knives are properly in place.

In addition to the 4140 heat treated rotors we also have inserted every bolt hole in these rotor segments with a replaceable 4140 heat treated insert. This has always been the second major weakness in these machines since they’ve been built. This is because when you have to take out and put in nearly 1000 bolts each time you do a knife change on a CM tire shredder or chipper and the bolts are going into mid-steel you will eventually strip out the bolt holes. And once you’ve striped the bolt hole out the only way to fix it is to weld the hole back up (which will never hold as good as a new hole will) and then re-drill and tap the hole with a special fixture that can be purchased from Columbus McKinnon. With our modifications the 4140 heat treated inserts that we’ve installed are not nearly as easy to strip in the first place. But if you do strip one you just screw the insert out and replace it with a new one and you’re back in business very quickly and not the several hours it takes to repair the mild-steel ones.

Also we have used what we call a cascading style rotor arrangement on installing these rotors back in the Primary tire shredder and the chippers. This allows for using of the knives up to six times if the knife does not become damaged. We used 2.2 size rotors along with 2.1 and 2.0 rotors in the two speed primary shredders. And in the chippers we used 1.9 rotors along with 1.8 and 1.7 size rotors. This way if you purchased both of these machines you would get six knife uses out of these knives. If you just purchased the two speed primary shredders or the chipper by itself then you would only get three uses out of each knife.

The cost savings for being able to use this knife over is quite sizeable when compared to having to buy new knives each time that cost anywhere from $25.00-$28.00 each new. And when all you have to purchase new are the 2.2 size knives and then Blanchard grind down the rest of knives needed to the next size for a cost of around $4.50-$6.00 each you can see the tremendous cost savings that this can provide over the life of the shredder.

We feel that the changes we have made to these machines will make them much more user friendly to operate and that we have addressed many of the weaknesses that these machines have always had since they hit the market in 1983. They’ve always been a very high production machine but along with this they have always been fairly high maintenance as well.  Unlimited Resources Corporation truly believes that our changes (updates) will eliminate many of these problems or at least minimize the problem to be more controllable. We have several machines running presently and were hearing nothing but good things so far. We still have some of these machines in inventory with these updates and welcome your calls.