Shredding stuff, especially woody materials, is a violent process and therefore the effectiveness of these machines is directly related to how much power is available from the gas engine. While there are some models on the market with engines having less than 5 horse power, we recommend 5 horse power as the lowest power level if you wish to be satisfied with your tool. A chipper shredder with a 5 h.p. engine will serve the needs of the average home landscape up to an acre, producing materials that can be easily handled by that level of power. For yardeners with lots of trees and lots of woody material to shred, these machines come with 6 and even 8 horse power, which of course cost more money. The more power you can afford to buy, the happier you will be with using that machine.
There are dozens of models of chipper shredders on the market. One of the most popular designs is a machine that actually does three different jobs well. It has a large hopper that you use to feed in leaves, weeds, twigs and small branches. On the side of the machine is a separate smaller hopper that is designed to chip branches up to 3 inches in diameter depending on the model. The third job occurs when you tip the machine over on its side and the large hopper is positioned to allow you to simple rake leaves into the machine, making the leaf cleanup in the fall a pretty easy task.
Cutting Designs - There are differences among various models in terms of the design of the tools actually doing the chipping and shredding job. Some shredding tools are immovable and others are pieces of steel that swing on an axel as they rotate. There are different kinds of cutting knives for the chipping job. Our position is that if you buy a good quality machine with good backup repair and servicing capabilities, the design of the shredders and the chippers is not important.
Output Screens - Some machines have a permanent screen through which the shredded material must pass. The machine keeps shredding the stuff until it is in small enough pieces to pass through the screen. Some machines offer interchangeable screens giving you the option to have stuff more course or finer in texture. We like that option. In any case, the screen needs to be easily removable so you can fix jams in the shredding compartment.
Safety Features - Most machines will have some sort of a barrier to keep material from shooting back out of the hopper potentially hitting you in the face if you are dumb enough to hold your head over the open hopper. Some machines make it very difficult to put your hands down into the hopper and that is a good thing. You want a machine that is designed to be very stable on the ground. You don’t need to have a machine that is danger of tipping over while in operation.
Cleaning Out Jammed Material - No matter what the company tells you, every chipper shredder is going to have material jam up in the throat of the hopper and cause you to turn off the machine in order to clear the jammed material. This is particularly likely when you are working with wet leaves and weeds. So assuming that event will occur, you want a machine that is easy to clean out when the jam develops. Have the sales person show you how that is done so you can judge whether it is easy or difficult.
Tips For Using A Chipper Shredder
Think Safety - The chipper shredder is a tool that deserves serious respect in terms of the potential for injury if not used carefully and correctly. The first rule is that no one else is standing around the machine when it is in use, ESPECIALLY CHILDREN AND PETS!!
Wear Safety Clothes and Equipment - A chipper shredder is probably the most violent machine used in the home landscape. Even a well designed machine is going to throw stuff back out of the hopper from time to time. The machine is going to vibrate and shake when it is struggling with a big load. It has moving parts that can seriously injure you if you do something dumb. So here is what you do:
1. You always wear long pants and shirts with long sleeves and sturdy shoes. No tee shirts, shorts, and sandals; you are just asking for an injury. A hat is probably a good idea as well.
2. You always wear eye protection. If you normally wear glasses, those will serve, although wearing safety glasses on top of the regular glasses is better. If you don’t wear glasses, then safety glasses are a must. The stakes are too high to ignore them. See the file on Eye Protection for more detailed information about safety glasses.
3. Most Important - Always wear ear protection when working with a chipper shredder no matter what size engine is used. Jeff has serious hearing loss now because when he was young and stupid, he worked with shredders for ten years seldom using ear protection. See the file on Ear Protection to learn more about your options.
4. You always wear sturdy gloves when using a chipper shredder. The materials you are shredding might have thorns or pointy edges. If material is thrown back up out of the hopper when you have your hands over it, you want gloves to protect you hands from being hit by those small pieces.
Use The Machine Safely - You will find out soon after you begin using your chipper shredder that you cannot feed material into the hopper is large volume fast. It will jam up very quickly. The trick is to learn how fast and how much material you can feed your machine without its jamming. Many machines come with a tamper tool that allegedly helps push stuff down into the shredding area. We do not recommend using those tampers.
Our experience is that when there is a jam, most times, it can be solved not by pushing the material down into the hopper, but by pulling material back up from the entrance to the shredding compartment so the material is feeding down in a smaller volume. We use a study branch at least 2 inches in diameter and at least two feet long; it is going to get chewed up over time as it makes contact from time to time with the shredding tools. You must never, never reach down into a hopper with your hands to free a jam while the machine is running; that is plain insanity. If you can’t free the jam with this stick method, always turn off the machine before you try to loosen the jam any other way.
One hazard to be alert for occurs when you are feeding small branches down into the large hopper. These branches are too small to chip for the smaller chipping hopper. Branches up to an inch in diameter can be handled in the large hopper just fine, but you need to be prepared for the machine violently pulling those branches out of your hands, if you are holding on to them too long. After a little experience you’ll learn to let that stuff go as soon as it engages with the shredding tools.
In most cases, the shredded materials pile up underneath the machine. It is wise to make sure that pile doesn’t get too high and begin interfering with the shredding process. We have a garden rake or a manure fork handy to keep pushing that shredded material out from under the machine as it builds up.
A gasoline engine on a shredder needs the same attention as any other gasoline engine on lawn care tools. Make sure it has oil, change the spark plugs each year or two, and especially keep an eye on the air filter. With all the dust and debris produced by the shredding process, that air filter can clog up faster than those on lawn mowers and such.