Alpine Magnum belt tension and the first stump with it

[marne]

Good evening gentlemen,

finally I was able to join the Alpine Magnum Club.
My unit is driven by a TS760 powerhead.

As in my country there are never any available, I took the chance and bought an slightly overpriced, beaten up one from another farer away country, but am happy to get access to tight spaces now and have access to an Alpine in general!
Even if it's from highest quality, the current price for a new unit is not that nice anymore, imho.
Should have added a new one to my small grinder fleet years ago.
Anyway, no more inaccessible stumps

I replaced this and that and did my first stump with it today.
Having read all the threads I found worldwide and watched all the videos, I was instructed and think I have used it in the right manner.
Holy, this thing really grinds fast, did not expect this from such a small unit. Nice.

Having read that the teeth can dull in a heartbeat, I was prepared and cleaned the stump well before.
Plyscamp's hint with grinding around obstacles until they pop out was very helpful too.

But no chance, 5 of 6 teeth where completely broken after 10 minutes. Completely!

Found the small stone, but entire annihilation that fast? Probably spoiled from my other grinders.
Maybe the next time...

To come to the point, now and then, it smelled slightly like burnt rubber, checked behind the cover and found fine rubber dust from the new belt the previous owner installed.

The aluminum pulleys had a slight edge, but did not care for it, as I expected they are there only for support and have no serious load on them.
I did not investigate the pulley on the cutterwheel side , but as the the (soft)alumium pulleys have some wear I was thinking that the (steel?) pulley on the head may not have any wear yet, not sure now anymore.

Anyway the main question:
What tension should the belt have and how do I check it?

Having read the TS760 manual which says like: "one should be able to press the belt down 1cm" did not give me any help... 1cm under what pressure would be interesting, but stihl did forget to mention this.

Any help is welcome, for sure regarding the alpine in general too.

Many thanks
Marne

 

[TimberMcPherson]

Okay I have a stumpmaster, the model the magnum was copied from. Been running it about 10 years with 2 bigger grinders and have learned its strengths and weaknesses and how to best apply it.

Belt has to be super tight, your not going to push a cm with your pinky.

Using a chainsaw grinders a different world to using a normal stumper. Due to having next to zero power and weight the only thing that allows it to do the job is its sharpness.

Number One rule--Its a STUMP GRINDER ONLY, its not going to like sand, dirt, stones or anything else. Your prep time on the stump is going to take more time than the actual grinding. You need a mattock, backpack blower and a slammer to clear around the stump and to clear debris as the grind progresses. If you dont your going to blunt or break teeth and unlike other grinders, you dont have the weight or power to just force it to finish the job.
Often we use it to help break up the stump, not grind it out to save on
Its hard work and often on jobs we find rotating guys every hour helps but thats not always practical, not much in treework is harder on the body than a day with a chainsaw grinder.

I dont quote stumps for the chainsaw grinder, as they are alot tougher to do and its highly unlikely that they owners have other options if they want the stump gone. I charge by the hour and the job takes what it takes.

For all its shortcomings, I wouldnt be without it, its great to do whats deemed "impossible" my other much bigger companies.

 

[marne]

Thank you very much for the helpful Information, gonna tighten the belt as it's very easy to push it.
And the next time there'll be even more cleanup around stump.

Cheers Marne