Another chainsaw dyno...

[huskihl]

You’re right, on dump trucks too. Our one dump truck had the front differential removed and repaired twice in less than a year.

First was the diff lock and gears, second was the input shaft. Bad drivers.

I’ve seen one redimix truck lay rubber on pavement with smoke rolling from the tires this year. I wished I got a video. My jaw was on the floor of my transport truck after witnessing that.

120 psi on the air axles and diffs not locked. Lol. Let ‘er rip

 

[Red97]

Well this ain't any good either.

I got the 4140 shafts, but forgot to read the fine print, or at least the lack of.

The 4140 don't have a straightness tolerance....



.007 on the good end .015 on the other.

Guess I'll have to go back to the 1045 shafts with the specs I need.

One step forward, 2 back...

 

[Nutball]

Looks like a giant shaft for just a few pounds of torque.

Does this mean dyno run costs will go up?

 

[Red97]

Looks like a giant shaft for just a few pounds of torque.

Does this mean dyno run costs will go up?

3/4"

 

[Nutball]

I guess it looks bigger than it is

 

[wcorey]

I got the 4140 shafts, but forgot to read the fine print, or at least the lack of.

The 4140 don't have a straightness tolerance....

You can't just straighten it?

 

[dahmer]

Any excess O.D. that you can throw it in a lathe?

 

[Red97]

You can't just straighten it?

More of a wobble than a bend. Tried for a couple hours and said screw it. All sorts of dents now from pressing it in the blocks.

Well after I tried to straighten it it is all over the place now.

 

[Red97]

Any excess O.D. that you can throw it in a lathe?

No size for size.

 

[wcorey]

More of a wobble than a bend. Tried for a couple hours and said screw it. All sorts of dents now from pressing it in the blocks.

Well after I tried to straighten it it is all over the place now.

At least you tried, that stuff can be pretty frustrating 'specially a wobbly one with multiple bends in a short length.
I used to go crazy with aluminum arrows and those bend easy...

 

[CR888]

I know everyone wants more dyno pulls...but I was enjoying the pigs

 

[Red97]

At least you tried, that stuff can be pretty frustrating 'specially a wobbly one with multiple bends in a short length.
I used to go crazy with aluminum arrows and those bend easy...

Yeh, first press had it .005-7" ok,ok, but dyno wants .003 or less...

So I kept going and going....

Yeh. I ordered a new shaft with a spec card. And it is long enough for 2 shafts.

 

[Duane(Pa)]

So you're getting a long shaft?

 

[Red97]

So you're getting a long shaft?

3 ft worth

 

[Dieselshawn]

The shaft I used in my dyno is 1” keyed. Never checked for straightness or wobble.

Bought from TSC store.

I’m guessing because it’s pretty short between the bearing blocks that there is no room for out of round.

My dyno runs smooth even when saws are spinning 15,000 rpms and the pump is turning 4,000 some rpms.

Any vibration is usually from the saw itself.

 

[Red97]

The shaft I used in my dyno is 1” keyed. Never checked for straightness or wobble.

Bought from TSC store.

I’m guessing because it’s pretty short between the bearing blocks that there is no room for out of round.

My dyno runs smooth even when saws are spinning 15,000 rpms and the pump is turning 4,000 some rpms.

Any vibration is usually from the saw itself.

The wobble is what got my $$$ tq arm once. In less than 2 months of use. Even though A lot of that extra wobble was caused by the slipped key. I still want to make sure it is by the book this time. .003 or less runout on the absorber shaft side.

.005 out at the shaft x the 16" length of the arm x the close to 8k rpm some of these saws are spinning 2:1 ratio. I don't blame those little bitty wires for snapping off lol.

 

[Woodpecker]

I guess it looks bigger than it is

That's what she said.

 

[P.M.P.]

I guess it looks bigger than it is

So you're getting a long shaft?

That's what she said.

 

[TreeLife]

it is long enough for 2 shafts.

Chit, wish mine was long enough for one good one...

 

[JimBear]

Well this ain't any good either.

I got the 4140 shafts, but forgot to read the fine print, or at least the lack of.

The 4140 don't have a straightness tolerance....

View attachment 250312

.007 on the good end .015 on the other.

Guess I'll have to go back to the 1045 shafts with the specs I need.

One step forward, 2 back...

Have you looked into Thomson Shaft? If I remember correctly it has pretty tight tolerances. We used it in the machine shop I used to work at. I believe a lot of what we got was 1045 case hardened but if I remember correctly you could get it in 4140. I am unsure of the pricing on it though.