Planers
An abrasive planer is similar to a wide belt sander (to be discussed under Sanders Wide Belt). They basically take the wood and plane it down to an acceptable tolerance or an acceptable thickness. When raw lumber or panels arrive at a plant they can be oversized in thickness and might therefore have to be machined to size. Once the parts have gone through the abrasive planer, they will have been brought down to the thickness the operator wants. As an example, should you want to work with solid wood and have its final size 3/4" thick, it might come in from the manufacturers of the lumber at 7/8" thick; it could also be substantially oversized, in which case the abrasive planer would be used.
If it is not tremendously oversized, a standard wide belt sander could be used. Abrasive planers work very similar to a wide belt sander. They have a rubber mat, which is used to feed the material, be it solid wood or a panel, through the machine. The wide belt, abrasive planer uses almost standard sand paper, excepting that it is very rough (40-80 grit), therefore it is called an abrasive belt.
There is a top drum, which is used to drive the belt, and a bottom drum that is the part that actually comes in contact with the material. This abrasive belt rotates around the top drum and the bottom drum. The top drum oscillates, allowing this wide belt to move backwards and forwards, thereby using different parts of the belt so that you do not get a wear pattern on the same part of the belt itself. In the case of a single top belt abrasive planer, if two sides of the material have to be planed down, the part has to be flipped and sent through the machine a second time, on the opposite side.
Abrasive planers are available in a top version as well as a bottom version. The top machine will sand from the top of the part and the bottom version will sand from the bottom; therefore, you could have one behind the other and in one pass plane top and bottom. Whatever belt mechanism you have on the top, as described above, will be exactly the same as at the bottom. Some abrasive planers can have two heads, one behind the other. Abrasive planers come in widths of anywhere from 12" to 72"; the width size is determined by the belt width not the belt length. The difference between a wide belt sander and a wide belt abrasive planer is that the planer does the initial rough work to bring the material down to size and the wide belt sander, which normally does not have as high a horse power as the abrasive planer, is used for finishing work. However, the basic construction of the two machines is the same.
The main differences between a wide belt sander and an abrasive planer are:
1) Abrasive planers have much higher horsepower’s.
2) The drum on an abrasive planer is steel, not rubber as in a wide belt sander.
3) To feed heavy oversized rough material some use a hydraulic feed mechanism.
4) Abrasive planers are for rough work. Wide belt sanders are for final finishing.
There are now combination machines that do the two processes in one. There is a planer head on the machine as a first head followed by one, two or three wide belt sanding heads.
This relatively new technology uses a helical head or spiral head as the planning head which is much quieter that a conventional planning head. On these types of heads the knives which are small segmented knives one next to the other can be rotated and/or replaced if one breaks or if one is no longer sharp.
MANUFACTURERS OF THESE MACHINES INCLUDE:
Activa, AEM, Timesaver, Cemco.
Copyright © MLS MACHINERY INC. 2008 All rights reserved.
|
