PTO leaf blower

[Donman]

I made this leaf blower from stuff I had laying around yesterday. After I took this pic and tried it out, I made two changes, (1). made a shroud to direct airflow better, (2) made skid at front so it wouldn't cut lines in the grass from angle iron runners. My Yanmar has 540 and 1000 rpm pto so I have a choice on blow power. Works good!

 

[leslie428]

What a wonderful idea, and I have an old air blower like this in the garage. I was going to throw it out. Now I can recycle. Thanks for your idea. Let me know if you have any other suggestions.

 

[jgbanshee]

Donman
Have you thought about adding gauge tires rather than skids to your blower?

 

[jimmer2880]

About how far does it blow them?

I have an old blower also that I amost tossed out today. Looks like it may have a new life what an awesome idea.

 

[Grrrr]

Great idea, I could do with one of them.

Where did the blower come from originally? Was it still a leaf blower in its previous life?

 

[Donman]

jgbanshee - I like the guage wheel idea! I think I'll try that.

Jimmer2880 - When the leaves are nice and dry they will blow 15 to 20 feet and clean up totally about 8 feet.

Grrr - The blower started life as a furnace blower. I had a couple of them but used this one cause it had a 3/4" shaft with enough shaft sticking thru for a pully on the back side which I needed for the thing to turn in the right direction and not stick out too far behind.

One more tweak that needs to be done is make a screen or shield so stray leaves don't suck in the intakes and clog it up.
The pto pulley I bought at an auction for $3. It was a flat pulley with tiny grooves for a flat belt. I chucked a rubber covered bolt in the drill press and set it up so it would turn this pulley slowly and allow me to cut the v-pulley groove with my 4" angle grinder.

 

[Huskerplowboy]

That green pulley looks like the ones that come off some PTO pumps on pull-type ag sprayers. We had a pump with a green pulley just like it that used a flatter type belt...

Cool project!

 

[Licklog]

Not being as creative or as handy as many in these groups I have stooped to mounting my hand held and back pack leaf blowers on my carryall and using them to clear my driveway of leaves and light snow.

I would like to use a PTO driven blower but the ones I have seen are pretty pricey for my limited use. Does anyone know of an "economical" source for a blower?

Licklog

 

[TobyH]

Check around your local furnace installer. They usually have a metal bin full of old furnaces you could probably swipe one off of.

 

[3RRL]

Great idea!
I've seen blowers used on golf courses to clear fairways of leaves. They are towable units run by separate engines. But I'll bet they paid a bundle for them.
I like your idea, it's very clever.
The wheels are a great idea too.

 

[SkunkWerX]

Be advised that a squirrel-caged fan will work well up to a certain speed, but if you over-drive it, and spin it too fast, it will go into a stalled-air condition, where it is spinning much faster , but, not able to push the same volume as it could at its intended speed. It has something to do with the intake side not being able to suck enough air fast enough so it creates a sort of vacuum in the cage.....don't quote me on the details, but hopefully you get the picture.

My understanding of this is not entirely clear, but, as best as I can remember, a squirrel caged fan needs a semi-restricted inlet to function efficiently, yet, it is the same thing that causes problems at the point you over-spin it.

Bottom line, if you think you can increase your RPMs by varying pulley sizes, and thus Super-charge your air output, be aware there is a drop-off point where you will lose a lot of air flow due to the aforementioned condition.

Ask me how I found this out?
Hint: when i saw the picture assocaited with the first post it brought back those memories....

 

[Grrrr]

Ask me how I found this out?

OK, I'll ask then

 

[oliver28472]

My brother has a big one made from a silo blower. It will get the job done. Too big for my little tractors though. He uses it on a 485 Case-IH.

 

[SkunkWerX]

OK, I'll ask then

I got a very large pulley, and a very small pulley, figuring i would spin a squirrel cage fan 4x as fast as it was rated.

What a surpirse when the output was equal to a desk fan on low speed.

 

[midcarolina]

My understanding of this is not entirely clear, but, as best as I can remember, a squirrel caged fan needs a semi-restricted inlet to function efficiently, yet, it is the same thing that causes problems at the point you over-spin it.

That is correct, The curve of the blades are engineered to work efficiently at a certain rpm range at a certain static pressure range.

For those of you who have one in your shop take a piece of cardboard or sheetmetal and partially block the intake you will hear the rpm's go up considerably.

On an application like a leaf blower I would make an adjustable deflector on the discharge this would accomplish the same thing, plus you can direct the air in a downward pattern..........

 

[Donman]

With 2 pto speeds plus infinately variable throttle positions and six gears forward, I should be able to find the right combination to work this thing the best. I'll let you all know what works best when I get to use it next. Believe it or not we still have a lot of leaves on the trees up here in Michigan.

 

[jimmysisson]

For those of you who have one in your shop take a piece of cardboard or sheetmetal and partially block the intake you will hear the rpm's go up considerably.

A fan is a pump that pumps air. When you restrict the intake, you're asking it to do less work, pump less air. That's why the rpms go up: less load. Like a vacuum cleaner when you cover the hose end, rpms go up. It's not the motor straining, it's the motor being happy to do less (until it overheats).
Jim

 

[midcarolina]

OK, Let me re phrase it, when you partially block the intake you can FEEL the increase in air flow.

household furnace type Squirrel cages are designed to run .5 or .8 " above atmopheric pressure. Simply put an amp clamp on the motor running with no intake restriction, make a note of the amp draw then check it with a little restriction.

You will notice with no intake restriction the amp draw will be far less than the rated full load amps IE motor not loaded. now play around with restricting the intake and you can achieve full load amps with maximum air flow............

 

[jimmysisson]

Yep, I agree, there's an amount of intake and an rpm when the motor/fan is most efficient.
Jim

 

[Densleigh]

Hi All,

This is my take on the use of a scrap furnace blower.

I run this at about 1000 rpm on the blower shaft from a standard 540 pto