Any ideas/help on a super yard vacuum

[Your Old Dog]

I spent the weekend working in the yard instead of in my shop. It came to me a heavy duty $900.00 yard vac would save a tremedous amount of time.

I don't have $900.00 but I do have a riding mower, 4x6 utility trailer and a spare 12 HP self/start vertical shaft Kohler motor for raw materials. I also have welding equipment and I've learned how to hold my tongue while using it. (line courtesy JS) I can build the blower unit

I would like to make setup where the motor/blower pins to the trailer tongue so it doesn't commit my trailer to this full time.

My question: What would be the recommend way to drive the blower with the motor? Is this an application for a centrifugal clutch or would belts, chain/sprockets and idlers be better? Maybe even a friction drive as in snowblowers?

I've done a search of the subject and found nothing. I do remember seeing a post from someone on the board who built one but I know it didn't go into specifics.

Thanks for any help you can give me.

Ray.........

[bernie l]

Ray-
Check out the attached link on the Hobart welding forum site. There's a pretty indepth discussion about lawn vacs.

http://www.hobartwelders.com/mboard/...ead.php?t=3038

take care
Bernie

[John Stevenson]

Ray, a word of warning here.
Holding your tongue whilst machining is different from holding your tongue whilst welding.
Sorry mate, whole new ball game.

[SGW]

I've got a small E-Z Rake lawn vacuum, with I think a 3 hp motor. On that, the impeller is put directly on the motor shaft. The vanes are made of pretty hefty steel plate -- 1/8" thick, maybe more, and there is quite a bit of clearance between the vanes and the housing.

Needless to say, you want to be sure this thing is balanced and is not going to blow up from centrigugal force when you fire it up for the first time.

[precisionworks]

Gingery's book "How to Design and Build Centrifugal Fans for the Home Shop" is availabe from used booksellers. There is one now on eBay: http://cgi.ebay.com/ws/eBayISAPI.dll...sPageName=WD1V

Or find an old wooddust collector with bad motor & you have the pressure fan. With 12HP available to drive the fan, you should be able to run almost any size collector that you build or buy.

I would try direct drive first as it's the easiest way IF your starter has enough torque to turn both the motor & the impeller.

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Barry Milton

[dsergison]

thanks bernie l,

that's my frankenstein hedgeapple blender.

if it can be driven over, it gets mulched. I'm utterly ruthless with the mower and the vac. It has held up quite well.

I used to be concerned that the impeller would chuck a blade through the housing and the back of my skull. but I'm happy to report that it hasn't happened yet. In reality the housing is 16ga stainless and is double wall around the periphery.

one of the great pains is the dumping system. when leaves and grass get mulched up so fine and bounce around as youre mowing they form a really thick mat that is hard to get out of the trailer. you'll want a good dumping system. I mean really good. the 40 deg tilt of most trailers is nowhere near adequate even with smooth metal bottom and sides. if it hinged further to the rear and could tilt to 80-90 degrees you would be in business. perhaps using a skinny hydraulic cylinder to make it dump.


you don't need to drive the blower with anything. just attach it to the driveshaft. it will work just fine in the horizontal orientation. you can buy nice keyed hubs with at pilot diameter for welding onto (gears, pulleys, anything) at farm supply stores. that's what I used.

[Paul Gauthier]

YOD
you can make a blower with all the suck you need by using the fan and the fan housing from and old snowblower. Find the largest one you can.

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Paul G.

[tattoomike68]

the link bernie l gave is very good.

I have built pallet loads of fans (12"-50")for green pea,bean,grape harvesters,leaf vacumes, and saw mills like that with a few changes.

I make the center hub go through fan back plate so a spacer is not needed on the crank.

I keep the blades strait and they go all the way to the center hub and get welded to the hub.(easy to lay out and keep balanced)

6 blade fans are better to get a weld on plus have space for a set screw hole over the key way(dont use a set screw, use a bolt and jam nut.they can be a royal pain to take off some day)

If rocks or golf balls are a problem you can add support to the blades near the center or a large thin ring to defect them to the middle where they wont do damage and will send it out at 100 mph.

bore and key a fan rotor last, it keeps the bore true after welding.

As far as mounting, you neet a tapped hole in the end of the crank, make the hub longer than the crank so a bolt and washer hold it tight to the crank.

if you build a fan rotor balancing is easy,put it on a shaft lighty between 2 live centers and spin by hand and mark the high spot and add some spot welds to the light side on the back of the blade.(i know other tricks too)

on a safty note stand clear when you first fire it off, a droped bolt or nut will come out like a bullet.
good luck.

[Your Old Dog]

Thanks guys for all the help! A lot of good information here, the welding site was also great reading as well. Looks like I'll go with the direct drive using the + couplings I've seen at Tractor Service Supply.

I'm pretty clear on everything except what type of bearing arrangement to use. Is it prudent to trust the blower wheel to just one bearing before it meets up with the motor coupling? I have yet to see that kind of photo anywhere that shows that end of the deal.

Ray.......

[sandman2234]

I just bought a lawnmower, used, and it has a blower with it. Haven't actually seen it yet (any of it) but the blower online is over $1100 new.
I used a pull behind lawnrack for the mower, and it works great. They are only about $225 new. Only drawback is dumping it, and if you have a pickup, just dump it in the pickup, and keep going. (The bagger fills up really quick)
If the lawnmower works halfway decent, I won't be spending near as many hours on mine as I did before.
David from jax

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Have gun, will travel.

[wierdscience]

I have a vac from a Scagg commercial mower.The housing bolts to the pump mount holes and the impellar keys right on to the engine shaft.

They last a long time,unless you pick up a big limb or a brick.The newer ones had the rear section of the blower housing held on with two tarp strap looking arrangements,the theory is if they pick up something big the housing springs out on the straps and ejects the junk.

I think if I were going to make one,I would rig the trailer with a good tight box and put it under vaccum with a baffle between the inlet and outlet.That way it would work like a cyclone separator instead of running the junk through the blower.

[Your Old Dog]

weirdscience, thanks. That's what I needed to know. It mounts to the blower housing and the other end of the shaft simply mounts to the motor. guess that means I'll want to flame cut the motor mounts to make sure I can position it without the blade rubbing in the housing. Maybe over size holes with large thick fender type washers to give me plenty of play.

thanks all. I'm good to go now!
Ray.........

[stiven]

Saw Red Green do this one time. You get a big trash can drill a hole in the lid and put a hose in the hole. be sure to seal around the hose well. Then you suck all the air out of the can through the hose. You've just created a giant vacuum.Cork the hose and then simply pop the lid off. The resultant suction of the air being drawn back into the can takes all your lawn debris ( leaves, sticks etc) along with it. It worked for Red.

[Ted]

I have thought of the same thing. I was going to use a suction fan off an old cotton picker I have.

I believe this would have enough suction to pick up maybe a four-foot strip.

These old fans have belt pulleys on them, and would work like a top on the motor you mentioned.

It’s a shame you live so far from me. I would give you one of about 5 or 6 I have laying around.

[3 Phase Lightbulb]

Summer Lawn Cutters:



Fall Leaf Removers:



Winter Snow Path Clearers:





[This message has been edited by 3 Phase Lightbulb (edited 04-15-2005).]