Quadchip shearbars.

[PeteB]

The GreenMech 152/202/252 were hard face weld and squared off with a surface grinder and they are still available. Newer machines have a shear bar which is hard through and through - but too hard and they can shatter and too soft means that they wear quicker. All blades and shear bars are, to one degree or another, a sacrifial item.

[openspaceman]

The GreenMech 152/202/252 were hard face weld and squared off with a surface grinder and they are still available. Newer machines have a shear bar which is hard through and through - but too hard and they can shatter and too soft means that they wear quicker. All blades and shear bars are, to one degree or another, a sacrifial item.

 

Thanks for answering my question inadvertently, so hard facing doesn't crack off? It didn't on the end of a solid nose bar nor on digger wear parts. Is the reason to using ordinary anvils one of cost, welding the hardfacing and grinding back being far more work than inserting a stock square edged piece?

 

To me the advantage of hard facing would be you could have the strength and resilience of a non brittle steel bar backing the wear face.

[Ty Korrigan]

Parts arrived at 12:30 today.

Just so the apprentice knew what to do we stripped out the shear bars again and replaced them.

Apprentice sharpened both rollers before together we fitted the new fixed roller motor, plumbed it in, filled up with hydro oil and ran her up.

3hours it took us.

Then off to a local job to chip up the thuya and lawson we'd left from earlier in the week.

Quadchip gobbled the lot greedy as a new machine.

Then a dead cherry 5" diameter which went in whole all the way without a blink or roller slip.

Chip quality is better.

Fine chips with no string.

Feeling quite proud of ourselves tonight.

Thanks as ever to Peter in parts and Mac in service at G.M H.Q for all their help.

Ty

[PeteB]

I seem to remember that the corner was milled off, hard face weld into the void and then the two faces ground back to give a 90degree corner - a lot of processes when an annealed through and through bar cuts down on the handling. I know of a tungsten tipped chipper blade, but that it is murderously expensive and will suffer damage and eventual wear.

 

Stick to what was original, factor in these costs and get on with life.

[PeteB]

I seem to remember that the corner was milled off, hard face weld into the void and then the two faces ground back to give a 90degree corner - a lot of processes when an annealed through and through bar cuts down on the handling. I know of a tungsten tipped chipper blade, but that it is murderously expensive and will suffer damage and eventual wear.

 

Stick to what was original, factor in these costs and get on with life.

[cornish wood burner]

Thanks for answering my question inadvertently, so hard facing doesn't crack off? It didn't on the end of a solid nose bar nor on digger wear parts. Is the reason to using ordinary anvils one of cost, welding the hardfacing and grinding back being far more work than inserting a stock square edged piece?

 

To me the advantage of hard facing would be you could have the strength and resilience of a non brittle steel bar backing the wear face.

Good evening openspaceman

Its not the danger of the weld cracking off that would worry me but the stress it would generate with the danger of crack propagation from weld to base metal.

By the time that anvil is heat treated I wouldn't think there would be much to chose between costs and I know which I would rather stand in front of. Hard face has little ductility and so is prone to cracking as it cools. Not important on something like a digger bucket but a chipper anvil? Much easier to control heat treatment than welding stresses IMO.

I may have misunderstood your original question but to clarify for others I'm sure it would be dangerous to hard face an originally hardened anvil. Neither hardface or a hardened anvil will have much ductility so cooling stress cracks will be present. Softer steel chosen to be hardfaced almost certainly will have a different composition and be able to absorb some of the welding stresses.

[Ty Korrigan]

Sharp rollers (but not too sharp)

Reminds me of 'Jaws' from the 007 movies.

Ty

[Gray git]

Told you you'd notice a difference that'd be worth the hassle. Nice job lads 👍

[openspaceman]

Good evening openspaceman

Its not the danger of the weld cracking off that would worry me but the stress it would generate with the danger of crack propagation from weld to base metal.

By the time that anvil is heat treated I wouldn't think there would be much to chose between costs and I know which I would rather stand in front of. Hard face has little ductility and so is prone to cracking as it cools. Not important on something like a digger bucket but a chipper anvil? Much easier to control heat treatment than welding stresses IMO.

I may have misunderstood your original question but to clarify for others I'm sure it would be dangerous to hard face an originally hardened anvil. Neither hardface or a hardened anvil will have much ductility so cooling stress cracks will be present. Softer steel chosen to be hardfaced almost certainly will have a different composition and be able to absorb some of the welding stresses.

 

Thanks Ian, I'm not planning on doing it but I've recently seen one of the 4 corners worn very round on our Heizohack in about 4 days of very hard work processing our 5 years worth of arb waste. The anvil is cheap enough, it's the down time that is costly.