Another chainsaw dyno...

[Woodpecker]

Sent tech support a summary of the runs.
He seen something was a bit off, wanted me to try a different hose arrangement.

Was thinking the large hose was acting like a lever and changing the true readings.

Built an arm to support the hoses, and brought the 2 straight out, and the 3rd as short as I could. Should have almost zero influence on the reading now.

That is why I have been including a "baseline" run that matches the old system with most all of these new tests. I'm not ready to claim the hp number is accurate just yet.

Really hoping I can keep the numbers in the ball park.

View attachment 263863

That logic presupposes that the old runs were moar accurate... whut with all the variables and such.

 

[dall]

That logic presupposes that the old runs were moar accurate... whut with all the variables and such.

so many variables and now he wants to do away with them
what shall we do with the variables

 

[TreeLife]

Variables

 

[Fruecrue]

so many variables and now he wants to do away with them
what shall we do with the variables

GFY with them?

 

[dall]

GFY with them?

lol can you show us how ?

 

[Red97]

That logic presupposes that the old runs were moar accurate... whut with all the variables and such.

so many variables and now he wants to do away with them
what shall we do with the variables

Variables

Only partly a variable thing...

This will be a lot more fun, and less questions if it falls mostly in line with the old runs/book specs.

I am pretty happy with the repeatability, which is the biggest concern.

Don't matter weather they measure 3 to, long as I can see the change +/- in the graphs.

But will be a lot better to keep everything close to the old system....

 

[dall]

Only partly a variable thing...

This will be a lot more fun, and less questions if it falls mostly in line with the old runs/book specs.

I am pretty happy with the repeatability, which is the biggest concern.

Don't matter weather they measure 3 to, long as I can see the change +/- in the graphs.

But will be a lot better to keep everything close to the old system....

so what about the variables ?lol

 

[Red97]

so what about the variables ?lol

They are variable

 

[Fruecrue]

lol can you show us how ?

Not for free...

 

[wcorey]

Seeing as the arm doesn't move more than thousandths, I don't think the lines affect it much unless they're routed/twisted/pre- stressed so the pressure twists them more.
Any torque they may have added sitting at "idle" should get zeroed out in calibration, just as the weight of the arm is compensated for.

 

[Red97]

Seeing as the arm doesn't move more than thousandths, I don't think the lines affect it much unless they're routed/twisted/pre- stressed so the pressure twists them more.
Any torque they may have added sitting at "idle" should get zeroed out in calibration, just as the weight of the arm is compensated for.

I don't think it was So much the little lines. But the big hose with the fitting tight could act like another tq arm.

Just touching it would change the reading. He thought it may have some effect.

 

[RI Chevy]

so many variables and now he wants to do away with them
what shall we do with the variables

Ha ha ha ha. Your so funny.

 

[Red97]

So, these are probably going to be on the dyno tomorrow.

Don't think I will post any numbers. But will be able to see the curves. Prolly 3 runs each on top of eachother.

I'm not ready to call it accurate. But it seems to repeat, and will show the difference.

Or should.....

 

[Red97]

3 runs of each saw.

About .6hp different max to max.

 

[Wolverine]

View attachment 264099

3 runs of each saw.

About .6hp different max to max.

That's lookin' pretty tight!

 

[huskihl]

View attachment 264099

3 runs of each saw.

About .6hp different max to max.

Any rhyme or reason? Are they back to back runs or after they’ve cooled down?

 

[Deets066]

Any rhyme or reason? Are they back to back runs or after they’ve cooled down?

Between the different saws I believe

 

[huskihl]

Between the different saws I believe

Ahh chit. I only saw the 6 upper colors and thought it was 3 hp curves and 3 torque curves.
I see the torque down at the bottom now

 

[Red97]

Any rhyme or reason? Are they back to back runs or after they’ve cooled down?

Top 3 are the 572, bottom 3 are the 7310 and the tq is the 6 lines towards the bottom.

 

[cuinrearview]

You cut one axis of the graph off