OT- Learn me about chippers/shredders

[rws]

Never owned one, but if they work, I could use it to reduce down stuff and make mulch for my gardens. What do I look for, and what makes one better than the other?

[metalmagpie]

I once had huge piles of leaves which I figured I'd shred and add to the compost bin. I got a 5hp chipper shredder (gas). Set it up, started it up, dumped in leaves. Nothing happened - they all just lumped together in the funnel-like hopper. I took a broom handle and tried pushing the leaves down. I had some limited success but realized it would nearly be faster to tear the leaves up by hand. I tried some small branches. They didn't self-feed.

I gave up and sold the thing.

I saw another one, much larger and heavier built, at a buddy's shop disassembled for maintenance recently. One of the major structural pieces of metal had stress cracks running in many places from the vibration. He was able to salvage it by MIG welding and grinding, but the moral of the story is that these machines don't last forever. They essentially beat themselves to death. And, you get what you pay for.

Look for large chute opening and stoutness of build. If possible, look closely with a good light for stress cracks.

For me, I've gotten along fine since with a leaf rake. :-) YMMV

metalmagpie

[sasquatch]

Years back i bought a "Billy Goat" brand chipper/shredder, i found it worked reasonably well, it had hammer knives in it, the thing would work fine on dry material, but damp or wet leaves would not go through it.

[Duffy]

I have one, bought it about 15 years ago; it is a 5 hp MTD with a B&S engine. It works as advertised EXCEPT the operator manual leaves out a few important points.
1) If you dump a basket of leaves in the hopper, they clump up. You lower the feed chute and sweep or rake the leaves in steadily. The shredder hammers act like a vacuum and suck the stuff through. It is pretty quick, but SOME plants, (like day lillies or hemp ,) have stringy fibers in the leaves and stems and dont shred very well.
2) The chipper blades are self feeding, and if you offer up a 2 1/2" stem, it will quickly stall the engine. You MUST hold on and feed it in slowly to get maximum benefit, (a bit like sex .) Small limbs are no problem.
3) A bit of maintenance now and then helps. For example, aside from changing oil and stabilizing the gas for the winter, remove and reverse the hammers after a season. Eventually they should be sharpened,( but you ARE a machinist, right?) I priced replacements. There are a dozen hammers and the company quoted $12.00 a pop. These are bits of HRS 1/4"x3/4"x3" with a hole in one end and semi-circular notches in both opposite corners, (but you are a machinist, right?)
4) If you pull the flywheel to acess the chipper blades, (which are sharpenable,) and service the hammers, Be VERY certain to torque up the retaining bolt! Otherwise, it will work loose, the wheel comes loose and BAD THINGS, almost happen! (Now how do you suppose that I learned that? )
If you are a fairly sertious gardener, then they are a good idea; maybe an 8 HP unit would be a bit better.

[J Tiers]

All the NEW ones are so "safe" that they do not work. As you found out, the "throat" is so small that leaves can't go there except in tiny little cupfuls at a time. (possibly the "vacuum type" work a little better)

You likely want an older Sears 5-6 HP one with a vertical shaft Tecumseh engine.... has a large squareish orange hopper. Made in the 1970s and 80s, I think.

This latter type has a throat about 15" x 5", and leaves go down it quite well, so long as you don't pack the hopper that feeds it, or feed it with mixed wet leaves and sticks. Ours shreds leaves etc for compost about as fast as I want to shovel them into it. I do a big pile that covers our driveway 2 foot deep every fall.

A few sticks won't bother it, but they bounce around for a while. Too many may jam the hopper, but then you rattle a stick around in it for a bit (use a long one that breaks fairly easily) and it clears. The rubber guard curtain is "OK", but lift the safety lid a little so leaves can get under the curtain.

The shredding part has 3 spinning bars about 4" wide x 3/8" thick, which whip the material through 3 "combs" attached to the scroll case under the engine. The bars pass through slots in the "combs", and anything in the way gets shredded.

2 things.... put a fuel filter in, and run it out of gas when you are done each time you use it.

The "Lauson" carburetor (none of this new preset and locked stuff) has a check valve that will get stuck if you let gas stay in it too long, even with "Sta-Bil". And the dust of leaves can get in the tank, getting drawn in with fuel and plugging jets, despite the screen in the tank. You may have to clean it, but at least you can, don't have to throw it away.

[tdkkart]

DO keep the chipping knives sharp, makes an amazing difference, just like a sharp drill bit.

DO NOT think you can shred your pruning shears(no, not me, but I got to fix someone else's)

The older Troy Builts are really capable machines, as are the Kemps.

I've got a later model Sears that I bought cheap, 98% of what goes through it goes in the chipper shoot, trying to get stuff through the shredding shoot is like trying to get a stupid mouse through a maze.

[rollin45]

I've got a 10 hp MTD, have used it several times per year for 6 years. If used with common sense and the tips from above, it can be a very useful machine. I bought it on impulse as I came across a clearance deal one day, and have never regretted it.

rollin'

[Johnh57]

I've been lurking a while trying to learn something - I have a new chicom 12x36 lathe delivering Tuesday.

We have a one acre yard with lots of trees and shrubs. I bought a "bearkat' chipper a couple years ago. It is great. It's roughly a 5 hp unit and it keeps up with our yard. Leaves are a problem, dry leaves are ok, wet leaves are bad, wet maple leaves are even worse. The bearkat has a perforated metal screen over the outlet - the size of the holes in the screen governs the size of the chips you make. They make a wet leaf screen that I have not ordered. Basically bigger holes.

They do beat themselves up. One of the "trees" we have is a hawthorne tree. They have really crooked branches loaded with thorns. They are a pita to shove into the small branches hopper. Keep a push stick around for those things - when the hammers grab the things the thorns will hang on to whatever they can - like sleeves and hands.

I chipped down a 12" mountain ash that died a couple years ago. Everything smaller than about 3 or 3-12" went into the Bearkat. Turned it into about 6 wheelbarrow loads of mulch.

[jep24601]

I have a 5 hp one and considering it's limitations I wouldn't go with any less than 5 hp. I mostly feed Japanese honeysuckle branches into mine and some oak. At 5 hp it has a tough time with 1" oak and 1 1/2" honeysuckle. If your just feeding small stuff into it it's fine. The blades need to be sharp or it will jam.

[kc5ezc]

Never owned one, but if they work, I could use it to reduce down stuff and make mulch for my gardens. What do I look for, and what makes one better than the other?

Look at it this way"
chipper: makes chips of variable sizes depending on material and how fast it is fed. Uses knives and an anvil that the 'stuff'' runs against to be chipped. Horsepower and safety are important.
shredder: usually uses hammers, some brands have hammers that swing, others are fixed and both have a screen to control the size of chips or sreds that you end up with. Usually slower that a chipper, but makes a more uniform product. I also have a BearKat hammer mil (shredder)that I am restoring. One of the old ones made in Neb. Weighs about 500 lbs; lots of cast iron. The new Bearkats are made in Oregon I think. I have never seen one.

I have a 12 hp Troy-Bilt that is several years old. Electric start, have changed blades one time. Book say they are non-sharpenable. Set of 2 cost over 120 bucks. I'll try sharpening the old ones when they need changing. For hard chipping I'll put dead seasoned blackjack oak up at the top of the list.
The DR chippers look like good ones. Mighty-Mac also makes a good product.
I use a leaf mulcher or chipper, like the sears on described above.
3.5 B&S motor and works great. It is about 25 years old. The new ones are not in the same ball-park.