Garden mulcher/chipper blades

[Charles in Aus.]

I dragged a mulcher home from the scrap yard . It's a nice size and with a 6hp Briggs engine should suit our garden well .
It started straight away and worked , but not too efficiently so I have dismantled it .
The blades are worn and I need to know if they should be sharpened to a bevel edge or have a square edge .
The key was sheared as well so it seems that even though it's not too old it has been worked too hard at least once .

The blades are not reversible and when spinning pass through the fixed fingers shown in the last photo .
If they do need to be square I will try welding a new surface to them .
As always , any advice is appreciated .

 

[cwtech]

The way the blades pass through the fingers, I would say the blade should have square edges.

If the center hole of the blades is flush on both sides, why can't the blade be installed on the shaft upside down ?? ...This would make the square edges the leading edges.

Most chipper/mulcher blades are designed to be reversible to expose a fresh leading edge.

 

[Charles in Aus.]

Thanks for the reply CWtech .

You would think.that they should be reversible but unfortunately they aren't . Both blades are welded together and the shaft will only pass into the blade mount socket from one side .
New blades aren't available , the machine was made in Australia for three years and production stopped last Christmas .

 

[caterpillar guy]

Nothing to lose welding them up. Just need to keep them as even as possible for balance. Looking at the fingers it spins through I would guess they are supposed to be square edges also. Though a straw chopper on a combine has square blades on the rotor while they have sharpened blades on the rack of stationary fingers at the housing.

 

[Charles in Aus.]

I used eight welding rods and it took a little over an hour to reface the blades . Back on and fitted with a new key it works very well .
Silly me let oil into the carburettor when tilting it over so it took a little longer than it should have to get it going .
We have just experienced a huge storm here , massive tree loss, branches everywhere and severe building damage so it's a timely repair and well worth the trouble .
Thanks for the advice .