Double head milling

[Stephen Blair]

 

Only ever used similar sized saws.

[Rob D]

I didn't try the winch system. I was more or less finished with it by the time you released it. I'm curious to see what else you guys come up with in the future to make the system easier to use.

 

 

We have some pretty big ideas - and now we have a good engineering firm to work with - so watch this space

[billpierce]

milling tother day with 084 and 076, had a pretty wierd thing happen where if i let go of the 076 throttle and the 084 was still going  the 076 continued to rev, at what i suspect was above max rpm.

 

i may be imagining it but all i can think of was that the 084 was driving the 076 piston which was sucking fuel and holding the butterfly open.

 

just wondering if anyone has had this. or can shed some light on this?

 

from memory the 084 rpm is 12.5k and the 076 is 10.5k

[Rough Hewn]

Ideally get two identical power heads, or two which rev the same in the cut. 

Wouldnt imagine it's doing the 076 any good.

[Rob D]

On 08/08/2017 at 10:51, billpierce said:

milling tother day with 084 and 076, had a pretty wierd thing happen where if i let go of the 076 throttle and the 084 was still going  the 076 continued to rev, at what i suspect was above max rpm.

 

i may be imagining it but all i can think of was that the 084 was driving the 076 piston which was sucking fuel and holding the butterfly open.

 

just wondering if anyone has had this. or can shed some light on this?

 

from memory the 084 rpm is 12.5k and the 076 is 10.5k

I'm guessing the 076 has a centrifugal clutch and you release the throttle on the 076 then the clutch dis engages from the drive sprocket. In that case the 084 cannot drive the piston on the 076 as the sprocket on the 076 would be free spinning (once you've released it's throttle).

 

But I'm not familiar with the 076 but would imagine the clutch works the same way as most saws.

[Rob D]

Had a collegue the other day using an MS880 and MS660 on some big beech - first time out on a double ended set up and he was loving it!

 

 

[billpierce]

4 minutes ago, Rob D said:

I'm guessing the 076 has a centrifugal clutch and you release the throttle on the 076 then the clutch dis engages from the drive sprocket. In that case the 084 cannot drive the piston on the 076 as the sprocket on the 076 would be free spinning (once you've released it's throttle).

 

But I'm not familiar with the 076 but would imagine the clutch works the same way as most saws.

yes same as most saws. once you had let both saws throttles off and then started the 084 the 076 did not rev itself, only once both saws were revving and you released only the 076 did it keep going. my guess is that the clutch couldnt disengage as the sprocket was spinning hard driven by the 084 which kept the 076 piston spinning and sucking fuel. perhaps this is more likely to occur with the larger rpm difference between the two saws.

 

just got a bar adapter from you so will give it a go with 660 and 084 and report back.

[Rob D]

4 minutes ago, billpierce said:

yes same as most saws. once you had let both saws throttles off and then started the 084 the 076 did not rev itself, only once both saws were revving and you released only the 076 did it keep going. my guess is that the clutch couldnt disengage as the sprocket was spinning hard driven by the 084 which kept the 076 piston spinning and sucking fuel. perhaps this is more likely to occur with the larger rpm difference between the two saws.

 

just got a bar adapter from you so will give it a go with 660 and 084 and report back.

Yep sounds good Bill - it may be just a peculiarity with the 076 that causes this as not found it to happen on more modern saws - see how you get on with the 660