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General Forestry => Sawmills and Milling => Topic started by: tom_the_sawyer on March 27, 2002, 02:47:25 PM

Title: anyone have any ideas on blowing  sawdust
Post by: tom_the_sawyer on March 27, 2002, 02:47:25 PM
  I got a free silage blower  and want to blow sawdust to a building or a pile from my bandmill anyone have any ideas and what type of pipe to use thanks for any info :D 8)
Title: Re:  anyone have any ideas on blowing  sawdust
Post by: Ron Wenrich on March 27, 2002, 03:09:59 PM
I've seen all sorts of things used for moving sawdust.  I've used stove pipe (doesn't hold up real well if moving lots of dust), and welded steel.  I've also seen plastic used.  I've never seen a silage blower used to blow dust.  As long as the fan is in good shape, I guess it will be OK.

The biggest problem is where you are making a turn.  That sweep will always eventually burn through.  

Another problem is how far you are planning to blow your dust.  The further you go, the less efficient it becomes.

I've always preferred a dust drag.  I've made them from old cornpicker chain and a small hydraulic motor.  

Title: Re:  anyone have any ideas on blowing  sawdust
Post by: Bibbyman on March 27, 2002, 06:17:29 PM
One of the first lessons I learned the hard way when I started sawing was to hold my glasses so the lenses were level to blow the dust off.  If you held them up square to your face,  the dust would blow right back into your eyes!   :o

Only took me a couple of times to figure that out.  ::)
Title: Re:  anyone have any ideas on blowing  sawdust
Post by: Frank_Pender on March 27, 2002, 06:30:49 PM
I move material from a shaper, planer, table saw and stroke sander all through a 6" pvc.  In the main route there are 4 90 degree elbows.  I have had no problem in moving the materials over a distance of 35' with a Grizzly 2 horse single phase motor.  You are also moving fine sawdust unlike the chips and larger sawdust I produce with my Mobile Dimension Sawmill.  Why don't you sell me your silege blower and use the money to purchase a Grizzly exhaust system.  8) 8)  I will  pay the frieght to Oregon. ;)

   In all seriousness Tom_the_Sawyer,  You will find that the pvc is a good idea.  But do not forget to place a plane wire inside the pipe to help with possible static inside the pipe.  Maake sure you ground it!
Title: Re:  anyone have any ideas on blowing  sawdust
Post by: Corley5 on March 27, 2002, 11:32:59 PM
Grandpa used sawdust for bedding for his beef cattle.  When he hadn't sawn enough in a season he hauled it from a mill east of town.  He'd set up his silo filler to blow it in to his sawdust sheds.  He'd back his pick up to the blower and shovel it in.  Sometimes he hauled sawdust in his big manure spreader.  Then he'd disconnect the beaters and back it up to the blower and unload with the apron chain.  Worked great.  I've been told that in cold climates PVC is better because material won't freeze to it.  That's what I've heard anyway.   I use an eight inch grain elevator for dust removal.  I run the sawdust into the manure spreader and spread it on the fields.
Title: Re:  anyone have any ideas on blowing  sawdust
Post by: L. Wakefield on March 28, 2002, 05:23:48 PM
   Yeah, you know that was the first thing I thought about when you got onto sawdust. I like planer shavings even better. They are fluffy and less apt to mold or compact and freeze when used as bedding. My problem is no place to store em. But if I were making them, I could use em as is where is. I'd always thought that you had to compost them or add extra nitrogen when you plowed them in or spread them, or the breakdown process would rob nutrients from the plants. That's what they say about using sawdust in the garden anyway. But it is organic material and so would add tilth and humus I guess. (NOW for the dumb question)- what do trees think about sawdust sent back into the woods and broadcast? I can't think that wood bee any problem.   lw
Title: Re:  anyone have any ideas on blowing  sawdust
Post by: Corley5 on March 28, 2002, 05:36:05 PM
Sawdust ties up nitrogen in the soil.  I would think that top dressing with a high nitro fertilizer would work.  The pallet mill I used to haul to spread their extra sawdust on an alfalfa field.  The alfalfa looked real good.  Some woods are acidic and fields may require liming too.  I haven't put any back on my own fields yet but it hasn't hurt the yields on Grandma's fields.  Yet
Title: Re:  anyone have any ideas on blowing  sawdust
Post by: Corley5 on March 28, 2002, 05:39:10 PM
Tom,  a silage blower is overkill for removing sawdust from a bandmill.  You really don't need something that big.  If you're not careful it make suck the whole mill in :o ;D :D
Title: Re:  anyone have any ideas on blowing  sawdust
Post by: Don P on March 28, 2002, 07:25:40 PM
RPM would adjust the CFM air flow...I've never heard anyone complain the vacuum was too good. Is the cut off adjustable, the point of the housing closest to the fan? If so snugging it up some would increase efficiency. I got a good book from Lindsay Pubs on blowers and fans, tells about testing and setup and fabricating fittings and the like, by Dave Gingery.

Sawdust is a net plus in nitrogen it just ties it up while composting but later gives it back up and more...slowly field applying it seems just fine to me. I blow into a little box trailer, its up by the blueberry patch waiting for a roundtuit right now :D
Title: Re:  anyone have any ideas on blowing  sawdust
Post by: Corley5 on March 28, 2002, 07:56:17 PM
In my experience with silage blowers and field choppers which have about the same blower setup.  The more volume you put through them the better they worked.  Chopping hay from a windrow and blowing it into a forage wagon always worked the best with big windrows.  Small windrows the hay falls at the front of the wagon >:(.  Big ones and it blows it to the back 8).  Same with blowing hay into a barn.  Drizzle going into the blower and it falls close to where the pipe goes in.  Full stream going in and it blasts to the other end.  I would think that sawdust would behave the same way.  We used to dry chop all our hay and blow it in the barn loose.  We had feed racks at one end and the cattle ate their way into the barn.  Way easier than feeding bales 8).  How big of blower are you talking about?  They do consume horsepower  
Title: Re:  anyone have any ideas on blowing  sawdust
Post by: kwall on March 29, 2002, 11:10:28 AM
I have used a grass blower with a 4 HP Briggs off My John Deere, I mounted it to the wall and ran a flex hose to My mill.
It will run on 1-1/2 gal's of gas in a eight HR day.
Title: Re:  anyone have any ideas on blowing  sawdust
Post by: Jeff on March 29, 2002, 01:48:31 PM
We no longer use any blowers. We have in the floor cornell elevators under all our machines. With the massive amount of sawdust we can generate cutting aspen on the head rig not to mention the sawdust that comes from the gangsaws, blowing sawdust was a problem. If you have neighbors within a half mile downwind you will here about it.  If blowing sawdudt you should have a cyclone to de-eccelerate the dust so it will drop straight down and not get in the air.

Eventually it gets EVERYWHERE if you blow it. Several years ago, back in our sawdust blowing days, I drove an olds cutlass. I had driven it for 2 years. The last winter I had it the heater fan quit blowing. Could not figure it out. It sounded like it was working, yet no air came in the car.

In that model you could open the hood and see the fan in its mounting up near the firewall.  I removed the fan from the mount and tried it. It blew like heck. So, I started looking in the duct where it was mounted, and found that there was a large piece of particle board in there that was blocking the duct. I mean it, it looked just like particle board. It was sawdust that had sucked in my vent everytime I started my car in the parking lot. It had drawn moisture and froze, solid as any manufactured board.  It took 3 days in a heated garage to get out the blockage.
Title: Re:  anyone have any ideas on blowing  sawdust
Post by: Ron Wenrich on March 29, 2002, 02:26:18 PM
We pan ours, along with the slabs and other debris.  There are cutouts for the dust to fall into.  Then we blow ours directly into a walking floor trailer.  We do get some that blows away, but not too much.

We have year round commitment for sawdust.  Chicken farms and horse farms are the big buyers.  What doesn't make it to the pan gets cleaned up by local farmers for veal, horse or hog pens.
Title: Re:  anyone have any ideas on blowing  sawdust
Post by: JD_Kid on March 30, 2002, 04:54:56 PM
Hi ya
i don't realy know but would plastic have a build up of static ele (spelling was harder than eating lunch at my school ).speed and sharp bends would wear ya pipes out faster also damp sawdust frezeing could be a prob,now on another matter bout useing sawdust as a fert it will tie up N as it rots all liveing things do once the rotting is over it is released ,the biggest prob is sawdust upsets carbon/N ratio so if mixed with bedding or a high N fert this helps keep things level ,lime can help as the bugs that use N like things sweet also some (manly evergreens)are acid and if used in big amounts will upset soil PH ..
catch ya
JD Kid
Title: Re:  anyone have any ideas on blowing  sawdust
Post by: Frank_Pender on March 30, 2002, 06:00:11 PM
Yes, you are correct on the statice electricity in the pvc pipe.  that is why I suggested that you place a wire through the pipe and ground it to your blower.   this is what I have done in my woodworking shop.  I have put about 20 cubic yards through since the instalation of the exhausting system and nara a problem.  No flashes etc have occured. 8)

   As to the ph etc in the soils, you might want to chekc with your local soils extension agent on that for the best information. :P
Title: Re:  anyone have any ideas on blowing  sawdust
Post by: JD_Kid on March 30, 2002, 07:35:08 PM
Hi ya
yep check with local guys on PH etc etc but if Carbon/N gets off level it upsets plants big time  ie roses if mulching around them ,bark is better than sawdust ya will find lack of flowers and a yellowing of plants till it rot's down fully if too much sawdust is used 2-6 inchs deep i'm talking about ,yep i did do hort at high school ??? had all the stuff needed to be a forestry dude 8) 8) but then timberlands come along and changed the set up  :'((kiwi's will know what happened)
catch ya
JD Kid
Title: Re:  anyone have any ideas on blowing  sawdust
Post by: BBTom on April 03, 2002, 08:46:02 PM
Tom,
I use a small 1 hp dust collector blower from harbor freight. It may be less expensive than a motor to run that silage blower. it was under $150 when I got it.  Works great with my WM40HDD42. I use 4" pipe and haven't had it plug up but once when I forgot to turn on the blower.  just had to turn it on and shake the pipe a bit :D
Title: Re:  anyone have any ideas on blowing  sawdust
Post by: DanG on April 03, 2002, 09:20:02 PM
Welcome a"board" Tombaumberger.  Stick around and share some of your knowledge with us. You might even pick up a tip or two along the way. Sounds like you've whittled up a stick or two, and you've got a nice saw. Tell us a bit about yourself. :)
Title: Re:  anyone have any ideas on blowing  sawdust
Post by: Bibbyman on April 04, 2002, 04:59:44 AM
I posted info and pictures sometime back about our dust collection system under the thread "Handy things around the mill".  Maybe there is some info there that may help. :P

https://forestryforum.com/cgi-bin/board/YaBB.pl?board=sawmill&action=display&num=994012887&start=0

This was an update to earlier postings I did on another forum earlier and an article we wrote for the Sawmill and Woodlot Management Magazine.

We used a blower from a $119 dust collector sold by Grizzly.  I think its rated at 450 CFM.  It has worked great and still going after three mills in four years.