Greenmech cs100 blade angles.

[Bob The Dog]

I bought a 2012 cs100 last year. Really good condition and very pleased. Rated to 4 inches which would be plenty for me. Anyway, when I first used it, it struggled with anything over 2 inches and would just knock the wood about, rather than cut it cleanly. Upon inspecting the blades, they appeared dull, so off they went to Saturn knifes and came back all shiny and sharp. In they went and cut well on conifer branches up to 2 inches. I tried today to chip some branches about 2 1/2 - 3 inches, well within the rating, and it just wouldn't do it. Really struggled and was pointless. I checked the anvil clearance, which was 0.5mm and cleaned it all out, but still no good. Spoke with a really helpful guy at greenmech who said that 2013 onwards, changes were made to the blade bed and the back angle changed from 15 degrees to 10 degrees ( I think i have that the right way around!). He was confident that the 5 degree difference may be the issue. The manual says 10 degrees. I spoke with scott at Saturn knifes who said their data States 15 degrees, and that's what mine would've been ground to. So, I've ordered a spare set of blades from them, to be ground at 10 degrees to see if there is any difference. I hope there is, otherwise it'll be an expensive trial! Wanted a spare set anyway. Was wondering whether anyone else had such issues and had managed to resolve them? I'll update once the new blades are in on the weekend. Thanks.

[Shane]

I think Spoons had a similar problem if I recall correctly...

Spoons, are you out there?

[Spoons]

Shane I am here.

 

Recently had this similar problem. Had my knifes sharpened at local place. Came back all shiny and sharp. Put them on and adjusted anvil. Struggled to pull anything in. Changed gap on anvil, still crap. Ordered new set from Saturn, bolted in and was back to normal. Compared the new set to sharpened set and then was a difference in angles on both edges. Now awaiting to get them sharpened to correct angle from local place. Hadn't heard of this difference in angles fro GM though.

 

Are you getting your brand new knifes re-angled? They should be fine if there are brand new.

 

Ross.

[Bob The Dog]

Hi Ross.

 

Yeah, having the new set from Saturn ground to 10 degrees, which is what the manual says, and seeing as the originals were ground to 15 degrees by Saturn, I thought it'd be worth a go. I'll send the originals off for a 10 degree grind if all goes well.

 

Bob.

[Bob The Dog]

Saturn didn't touch the main angle (27 degrees), so I wonder if perhaps the previous owner had them re ground and that angle may also be incorrect? Would have thought the odd few degrees would make such a difference!

[nepia]

Not directly related but may be a thought for others... When I send off my Jo Beau blades I include a copy of the relevant bit of the manual that shows the angles. Simples.

[Bob The Dog]

Sounds like a good idea! Can't fault Saturn. They've been very helpful and have ground to the angles according to their data sheet. Only hope it is something as simple as incorrect angles. Perhaps on the next grind I'll add a little note to confirm the angles. Thanks for the advice.

[Spoons]

Not directly related but may be a thought for others... When I send off my Jo Beau blades I include a copy of the relevant bit of the manual that shows the angles. Simples.

 

I did this, but they still came back at the wrong angles..... Clearly thought they knew best? Also, how many sharpens can these take before they are too small? Does it matter if they are ground over the bolt holes?

[GlobalNewark]

Although I am Jo Beau salesman the most crucial thing with all these gravity feed chippers is the knife angle & adjustment. The knives need sharpening to the exact degree at the cutting edge & the underside. What is also crucial is the measurement between the edge of the blade & the outer face of the drum, as the blades are ground this reduces which is why shims are supplied to keep this height constant.

 

Don't know what GM's specs are but I would check this also, if all the above are not 100% it will not pull the material in or chip. When you here people say this is an exact science it is very true.

[GA Groundcare]

GM CS100 comes with a pair of shims and a correct thickness feeler gauge from factory.