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The Powermatic brand has always been synonymous with top-quality woodworking machines, priced accordingly. This is a 2 HP 220v, 8 jointer like the Jet model immediately above. The difference is in the extra measure of quality. Right away, I noticed that the bed is a whopping 82 long which means straight joints on 10 to 12 foot lumber without loss of control. Powermatic offers a unique Parallelogram design that assures maximum close proximity between the tables and the cutter head for an improved finish at any depth-of-cut adjustment. This feature also assures that the infeed and outfeed tables on this jointer will remain in perfect alignment with each other after years of rough use. This Powermatic jointer comes standard with a 2 HP, 220v, single phase motor but is also available with a 3 HP, 3-phase, 220v motor at extra cost. Fence tilt adjustments are by hand wheel and extend left or right 0-45 degrees. The 3-blade cutter head executes 21,000 cuts per minute. Street price is about $2100.
LAGUNA TOOLS 12" INDUSTRIAL SERIES JOINTER
Boasting an overall table length of 98 inches and weighing in at 1250 Lbs., this jointer from one of the world's finest manufacturers of stationary woodworking machines is no lightweight contender. This jointer packs a 5 HP, 3-phase, 220v motor that turns a 12" cutter head with ease through the densest of hardwoods. The heavy, cast iron tables are supported by a parallelogram mechanism that keeps the tables as close to the cutter blades as possible at all depths of cut.Two hand wheels, thoughtfully mounted on the left side of the cabinet make adjusting this machine a breeze. Priced at $5400.
Just to see what a big industrial jointer looks like, lets take a peek at this 16-inch jointer by Powermatic. This is probably way more than most woodworking shops would ever need or could ever justify but for a large production shop, this giant jointer may just be the ticket. The huge, 16 cutter head width insures long intervals between knife changes.
This machine has what is known as a helical head which means that there are 58 two-sided small blades that are inserted into slots in the head in a spiral-like pattern. There are two additional knives used for rabbeting. This type of head produces extremely smooth cuts up to a maximum depth of ¾.The 5200 RPM speed of cutter head rotation gives you 20800 cuts per minute. The tables include rabbeting ledges for cutting rabbets as deep as ¾. A 96 bed assures smooth cuts along long lumber and easy lumber handling. The standard motor is 7.5 HP, 3-phase wired for either 230 or 460 volts. The machine weighs in at 1280 Lbs. with a shipping weight of 1400 Lbs. 800 CFM dust collection (minimum) is required through a 6 dust port in the enclosed cabinet. Street price is around $7800.
Bob Gillespie
(C) 2010 Robert M. Gillespie, Jr

SIDE-BY-SIDE COMPARISON CHART: JOINTERS
| Delta 6" | Jet 6" | Jet 8" | Powermatic 8" | Laguna 12" | Powermatic 16" | |
| Bench Top | JJ-6CS | JJ-8CS | Parallelogram | Industrial | Parallelogram | |
| Jointer | Jointer | Jointer | Jointer | Jointer | Jointer | |
| Cutter Width | 6" | 6" | 8" | 8" | 12" | 16" |
| Table Length | 30" | 48" | 66.5" | 82" | 98" | 96" |
| Motor | 10 Amp | 1 HP | 2 HP | 2 HP | 5 HP | 7.5 HP |
| No. Knives | Two | Three | Three | Three | Helical | Helical |
| Weight | 35 Lbs. | 258 Lbs. | 398 Lbs. | 616 Lbs. | 1250 Lbs. | 1280 Lbs. |
| Street Price | $270 | $550 | $1300 |
$2100 |
$5400 |
$7800 |
ALL ABOUT JOINTERS
Rabbeting can be accomplished on some jointer models but I prefer to use the table saw for this task. Chamfering, or making angled cuts, can be performed on these woodworking tools by tilting the fence. Accurate jointing or chamfering requires that the cutter head knives in these machines be adjusted precisely with reference to the outfeed table. The edge of each cutter head knife must be exactly at the level of the outfeed table: not above or below it.
The principal function of a jointer is to put a straight, smooth, level edges on boards in preparation for edge-to-edge glue-up.
In most cases, sharpening the cutter knives requires that they be removed completely from the jointer cutter head and then replaced and adjusted after sharpening. This is why I recommend the use of solid carbide as opposed to high speed steel knives in a jointer: Carbide lasts a lot longer and that means less time and effort has to go into removing, replacing and adjusting knives. Buy two sets. That way, you can continue to use your jointer while the dull set is out for sharpening and you will always have a sharp set waiting. Come to think of it, you should consider doing this with all of your woodworking tools: extra blades on hand for the table saw, band saw, circular saw, etc. will keep your shop running smoothly and continuously.
Always unplug your jointer from electrical current before attempting any adjustments to the knives. In my jointer, an 8 Rockwell/Delta classic, the knives are removed and replaced by using a flat wrench that came with the machine. This wrench is used to loosen and tighten the hex head machine screws that press against the knives and hold them in place in the cutter head of the jointer. It is very easy to round over the hex heads, so I am very careful not to do so. I purchased a gadget that helps me align the knives with reference to the outfeed table of the jjointer. It magnetically attaches itself to the surface of the outfeed table and magnetically attracts the knives upwards and holds them in position while I tighten the hex bolts. Each knife (there are 3 in my machine) must be in the extreme vertical position before it can be individually correctly adjusted and tightened. When all 3 knives have been set properly, they should just touch, but not lift, a flat piece of wood laid on the outfeed table, extending over the cutter head of the jointer. They must do this across the entire width of each knife.
Today we tool a look at a wide range of jointers. Jointer size is most commonly determined by the full width of the cutter head. A 6 jointer makes a maximum 6-wide cut. An 8 jointer makes a maximum 8 cut and so on. It would be rare to use the entire width of even a 6 knife at once: The real advantage of wide blades is that you can move the fence across the jointer bed to use a sharper place on the knives when part of the knives becomes dull. The wider your knives, the more use you will get out of them before it is time to re-sharpen. I usually start with a sharp knife and adjust the fence all the way to the right end of the cutter head. I can then move the fence to the left, in increments a bit wider than the maximum board thicknesses, until the knife edges are dull across their entire width.
Sometimes, with curly or wavy grain structure, you will experience tear-out from the lumber edge even with sharp knives. Sometimes you can turn the board around and run it through again with very shallow cuts until the edge is fully jointed and the tear-out is gone. At other times, you may have to settle for a sawn joint made on the table saw. Usually you can make fairly good glue joints this way, if you have to, but a edge made on a jointer is always my first choice.
The depth of cut is determined by the height of the infeed table with reference to the outfeed table. The lower the infeed table, the more wood is removed with each pass over the jointer. It is not a good idea to take off too much wood in a single pass. The chances of tear-out increase with the depth of cut and you may end up removing more precious wood than you really need to, to get your perfect joint.
Bob Gillespie
(C) 2010 Robert M. Gillespie, Jr









