Chipper Chipper Designs - Hammers vs knives?

[jeffinsgf]

That's exactly how I figured it should work, but this goof ball chipper/shredder I've got through me off, especially since I never really used it more than a one time experiment. It behaved poor enough that I wanted to a) ensure anything I else I was considering was of a different design, and b) ensure that other units actually work better. Perhaps what I have is not technically a chipper/shredder per se, but just a shredder if such an animal existed. Any case, all is clear now - thanks all.

Why would you want to chip hawthorn, anyway? What are you going to do with the chips? I would advise against using them as mulch. You'll find those thorns every time you work in your beds. My bane is honey locust. I use my chipper shredder a lot, but mostly on cedar. The honey locust slash goes straight to the burn pile.

 

[ADin]

I won't use the chips for mulch but will pile them up out of the way to decompose and occasionally add some to the compose pile when I need more carbon. Surprisingly, I looked for thorns in the chips and couldn't find any although I know there has to be plenty of them in there.

My main reason, however, for not burning is because the act of getting the downed hawthorns to remaining burn pile is still worst than chipping (need to cut everything down and load one wagon at a time). It's also much slower do to distances involved. I had many strategically place burn piles when I did the first pass of thinning about 5 years ago, but most of them were only borderline safe for burning and I since have relatively nice grass growing where I would need the piles to be. The only place for burning now is at the far back of my property. I also remember burning all weekend for weekends on end (I think 14 in total) in 90+ degree weather. The piles were so hot I could only get just close enough to throw the wood on (very miserable) and then I would wonder all night if I really got everything put out good enough since I didn't want to burn down mine or my neighbor's woods.

 

[veefre]

I'm out here on "only" 1/3 acre in California. However the property has tall chain link fences covered with English ivy, one is 12 feet tall, and I had to get a chipper/shredder to process all the trimmings.

So about 13 years ago I got a Patriot 6 hp CSV at HD. The price was good, under $400. I notice that a similar machine these days runs over $1000.

Anyway, the machine has two blades for the chipper chute (3" max) and about six hammers (I think) for the shredder rotor. It does a pretty good job reducing the ivy to compostible mulch - generally I can fill a couple of cubic yards of compost bin each year with just the ivy. The ivy nearly all goes through the shredder hammers - there aren't many straight stems that would need the chipper. However I do use the chipper knives to process branches from various trees I've planted that I've decided to stump (avocado, lime, lemon) or remove completely due to poor placement (too close to buildings or blocking sunlight for veggie garden.

The Patriot is a good enough machine. I can't compare its operation to others because it's the only one I've had. In the past 13 years I had to rotate the hammers once, and sharpen the chipper blades twice. I just use a 6" shop grinder to sharpen the blades - and finish off with a whetstone to remove the burrs. Have had no problems using this method. It's not like it's a precision chef's knife. I do like to do a staged sharpening, with a slightly blunter leading edge for more strength. But I doubt that it makes much difference. The last time I sharpened them (yesterday) they were still pretty sharp so I just touched them up.

The 6 HP Techumseh engine used to give me a lot of grief. That's until I figured out it has a pilot jet adjustment screw on the bottom of the carb bowl. Now I just enrich it maybe 1/4 to 1/2 turn for starting, and then adjust to where the motor runs fastest and smoothest at full idle. It burns some oil, always has, but I just top it off before each day's use and that seems to work out ok.

I also had to replace the outboard bearing about six years ago. Most likely because I used to hose the thing down to clean it inside and out while running, and some of the water must have gotten into the bearing. I don't do that any more, no need. I keep a spare bearing around just in case, though.

I'm a bit shocked by the price of replacement hammers, though. The current set will need replacing soon (already turned once), and the list price from Patriot is $75. Ten years ago I think the price was $40. Still seems to be a lot for just some cut, twisted, and hardened alloy steel bits (I'm a machinist). I've looked around but haven't been able to find any alternate sources, so I'm guessing these are unique to the Patriot line. I've thought of fabricating a replacement set, maybe out of 4130, but would have to find someone with a heat treatment oven to harden them.

Of course I've also learned not to put dry wood down the chipper or dry branches into the shredder. Dry sticks are abrasive and wear out the knives and hammers quicker than wet stuff. Make sure the big branches are straight so they'll feed themselves through the chipper chute. Dribble the ivy clippings in gradually, so they don't ball up and clog the shredder chute. Keep the collection bag flowing - a clog there will back up to the rotor and can cause the shredder to stall out. And then freeing the rotor can be a real chore.

I also find I have to wear a full face (beard) respirator when I trim the ivy - I'm a little allergic to the fuzz/dust the ivy produces and would rather not wake up the next morning with red eyes and a hacking cough. No hawthorne here, but I generally don't try to chip or shred roses or blackberry canes. Those go in the green waste for the county to worry about.

Most recently I had to service the rotor because the bolts holding the rotor housing to the motor loosened up and started making a squealing noise. Turns out three of the bolts had rubbed enough to wear off their grade markings. So I got new bolts, touched up the blades, and all is well now.

As far as ear protection and gloves... I will wear gloves when chipping straight stuff and easily managed leaves. However I'm a bit leery of a gloved hand getting snagged by an ivy vine and having my arm dragged into the shredder hammers. So I don't always wear the gloves. As for ear protection, the machine is not so loud that I feel I need it. And so far haven't been hit in the ear with shrapnel. I do wear good polycarb glasses though.

 

[newbury]

Nice post for a zombie thread.

 

[veefre]

Yeah, it's been a while, but it was a good discussion I found via Google.

Anybody ever find cheaper sources for shredder Y-hammers?