Chainsaw Dyno?

[Red97]

Anyone interested in a chainsaw Dyno?

Built mine last year, and have most all the bugs worked out now. Almost 1000 runs on the current setup.



If you all want to see some build/progress pics along the way let me know and I will dig them up.


Here is a printout from the dyno system. I use a waterbrake, with shafting/fatherless chain to mount the powerheads on.

Runs are done just like cutting wood. High/max rpm then I start applying the load and bring them down to 5000 rpm over a 9-12 second time.

 

[Ronie]

Yes, I would like to build one . I got the basics and have some kart dyno builds book marked but one specifically for a chainsaw would be helpful.

 

[Red97]

Yes, I would like to build one . I got the basics and have some kart dyno builds book marked but one specifically for a chainsaw would be helpful.

I will add some pics as I can dig them up.

I will say they get expensive quick lol.

Without the software/ data acquisition it gets hard to see gains/losses.

 

[Ronie]

I don't know if I can afford the software, at least in the beginning, so I'll have to figure it up myself. One thing I can't find is where to buy the 22 tooth sprocket and the size of the pump I need.

 

[Ronie]

I use a waterbrake

Had to look it up, I've been planning on building one with a hydraulic pump but I'd like to see how yours was built.

 

[Red97]

I don't know if I can afford the software, at least in the beginning, so I'll have to figure it up myself. One thing I can't find is where to buy the 22 tooth sprocket and the size of the pump I need.

Danzco/6k products can make them but it will be 2-500$ sprocket most likely.

 

[Ronie]

This is like the one I've been thinking of.

 

[Ronie]

Danzco/6k products can make them but it will be 2-500$ sprocket most likely.

That's a lot! I think I can come up with something like connecting from the chainsaw to a regular chainsaw sprocket attached to a bigger regular chain sprocket and get the RPMs down that way.

 

[Red97]

Current short arm setup. With the load cell. Can see the bar/chain in the back ground.


Data boxes rubber mounted


This is still when it was a long arm setup. But the short arm shows better resolution.



Everything is rubber mounted to keep the vibes away from the electronics

The pink brake was originally a portable setup for go karts.

I use a 2:1 reduction. 7 on the saw 14 on the dyno. I have had some saws close to 17k before. (8500 rpm at dyno)

I would not want too many chains and sprockets spinning like that.


Nice thing about the water brake is it can load until you run out of water from the well. Don't have to worry about water getting hot as it is discharges.

I looked into an inertia dyno. But sizing one for high rpm and low tq of the saws was difficult.

And 1 setup to run 1hp to 15hp is almost impossible for a good dyno run you need at least a 6-8 second pull

9-12+ being better. But long pulls at high load will smoke saw clutches. That was another reason to use a brake dyno. Closely resembles cutting technique. High rpm to low.

 

[jasent]

Tagging. Very interested

 

[Ronie]

Current short arm setup. With the load cell. Can see the bar/chain in the back ground.

View attachment 294
Data boxes rubber mounted
View attachment 295
View attachment 296
This is still when it was a long arm setup. But the short arm shows better resolution.

View attachment 297

Everything is rubber mounted to keep the vibes away from the electronics

The pink brake was originally a portable setup for go karts.

I use a 2:1 reduction. 7 on the saw 14 on the dyno. I have had some saws close to 17k before. (8500 rpm at dyno)

I would not want too many chains and sprockets spinning like that.


Nice thing about the water brake is it can load until you run out of water from the well. Don't have to worry about water getting hot as it is discharges.

I looked into an inertia dyno. But sizing one for high rpm and low tq of the saws was difficult.

And 1 setup to run 1hp to 15hp is almost impossible for a good dyno run you need at least a 6-8 second pull

9-12+ being better. But long pulls at high load will smoke saw clutches. That was another reason to use a brake dyno. Closely resembles cutting technique. High rpm to low.

Very cool, I like seeing your runs on the other forum.

 

[jasent]

I’m curious how much ya got in to a setup like this. You can pm me if you’d like. Seriously considering building one for my self would be nice to see my gains and have proof for my customers
2-3k?

 

[Red97]

I’m curious how much ya got in to a setup like this. You can pm me if you’d like. Seriously considering building one for my self would be nice to see my gains and have proof for my customers
2-3k?

All in I am well over 6k and that is buying some stuff used and having a lot of material on hand to complete the stand.

Brand new setup like my brake starts at 7k and will be well over 9k by the time you get a stand and sprockets etc.

You could possibly setup an inertia dyno for 3k. But will have loads of time involved.

The data acquisition and weather corrections are the biggest factors. Hand calculating takes tons of time. Slight changes in weather can have large impact on power output.

I believe 6k is about minimum for a almost useable dyno.

They are a love hate relationship for sure. You can actually see the numbers. But seeing the numbers can be hard at times too. Strong saws out of the box. Not seeing the gains you had hoped. Lots of things like that.


If you don't have an easy setup, or one that can't do multiple runs in a row it will take a lot longer than expected to perform runs.

 

[Blasterman]

I made mine with the stuff that I had, I can only compare with mine. I can load the saw and get a pressure at what rpm. It is more of a check how they run and brake in runs.

 

[jasent]

All in I am well over 6k and that is buying some stuff used and having a lot of material on hand to complete the stand. Brand new setup like my brake starts at 7k and will be well over 9k by the time you get a stand and sprockets etc. You could possibly setup an inertia dyno for 3k. But will have loads of time involved. The data acquisition and weather corrections are the biggest factors. Hand calculating takes tons of time. Slight changes in weather can have large impact on power output. I believe 6k is about minimum for a almost useable dyno. They are a love hate relationship for sure. You can actually see the numbers. But seeing the numbers can be hard at times too. Strong saws out of the box. Not seeing the gains you had hoped. Lots of things like that. If you don't have an easy setup, or one that can't do multiple runs in a row it will take a lot longer than expected to perform runs.

Well ya haven’t scared me off yet. Even if it took me a year or more to get the parts and all put together. Stand I could build my self. Not a problem there. I like the water system better than the hydraulic system I’ve read about. Letting the computer do the math take some errors out of the equation so it’s more repeatable. I’d love to see some progress pics and parts lists. Could charge for dyno time to get returns a bit faster. Once it’s together and dialed in and the learning curve flattens out.

 

[Red97]

Well ya haven’t scared me off yet. Even if it took me a year or more to get the parts and all put together. Stand I could build my self. Not a problem there. I like the water system better than the hydraulic system I’ve read about. Letting the computer do the math take some errors out of the equation so it’s more repeatable. I’d love to see some progress pics and parts lists. Could charge for dyno time to get returns a bit faster. Once it’s together and dialed in and the learning curve flattens out.

I don't really have any parts list other than the brake, shaft, bearings, cutterless chain, and 14t sprocket.

Everything else was made to suit.

Electronic package is the expensive part.

For a brake/load cell dyno about the cheapest I have found was 1200$ to include a weather station.

They do have some diy electronic packages and free software. But if you have any issues no tech support.

 

[Red97]

Here is the first setup with the waterbrake kart setup the blue arm and old data setup was hand held and just scrolled info on a lcd screen. Supposed to hook to to a receipt printer and print the data but that part never worked right.
Had a few issues with that blue arm too. Decided to ditch that setup for what I am using now.

 

[Blasterman]

Where do you get the cutterless chain. I ground mine off because I have never seen cutterless before.

 

[Red97]

Where do you get the cutterless chain. I ground mine off because I have never seen cutterless before.

 

[Ronie]

I made mine with the stuff that I had, I can only compare with mine. I can load the saw and get a pressure at what rpm. It is more of a check how they run and brake in runs. View attachment 335 View attachment 336 View attachment 337

That's the type I would like to build.