Jointer-Planer Syllabus


Resource Guide for the Jointer/Planer in Small Workshops

"Essential Workhorses for Smoothing, Squaring and Dimensioning Rough-Sawn Wood"



A Little Bit of History

homemade jointer 1925

According to the Oxford English Dictionary, as a term "jointer" (spelled then, joynter), dates back to 1687, but naturally it refers to the jointer hand plane. Evidently when the mechanical jointer appeared, it  was labeled "jointer" because of the resemblance to the function of the jointer hand plane.

Historically, according to Herman Hjorth (in Machine Woodworking Peroria, IL: Bruce Publishing, 1937), around 1790, the Englishman, Sir Samuel Bentham is said to have made the most remarkable and ingenious series of inventions, which changed woodworking from a handcraft to an industry. The most important of these was the principle of rotary cutting, which is used in all modern planers, jointers, shapers, molders, and matchers. He also invented veneer-cutting machinery, segment circular saws, tenon cutters, boring machines, and sharpening machines.

Bentham even suggested tilting the table or saw and fences for ripping and crosscutting. Bentham may, therefore, rightfully be called "the father of woodworking machinery."

These inventions were patented in the years 1791 to 1793, and manufacture started immediately in the London residence of Sir Samuel's more famous brother, Jeremy Bentham.

The frames of the machines were made of heavy timbers bolted together and only the cutters and bearings were made of metal. Not until about sixty years later were woodworking machines made entirely of  metal.

Read more about the origins of the power planer here

Table of Contents:

First, a little bit of history continued; then, basic considerations:treating the jointer before the planer, I divide each of the two sessions into the types of jointers and/or planers , including the typical prices of representative machines in each group,

(a) the anatomy of each tool,

(b) models of each tool,

(c) an analysis of each constituent part as its relates to the different tools,

(d) operation,

(e) setting knives in jointer/planer cutterheads,

(f) maintenance and tune-up,

(g) accessories, and

(h) safety.

Two additional sections are,

(1) summary of features to check in assessing the quality of a jointer and a planer and

(2) the annotated bibliography directs you to numerous other sources.

The First Portable Jointer

Hjorth discusses the emergence in 1914 of the first "portable" jointer. (Its so-called portability is not too bad, either, at 34 lbs; in 1914, though, it would be powered by a DC motor. )  This jointer was produced in Buffalo NY by the J D Wallace firm. Hjorth's photo is, frankly, terrible, but the back cover of Shopnotes 48 (Nov 1999) features a beautiful color photo, with the caption (on the right side of the photo below.

j d wallace 1914 portable jointer

The "portable" jointer above features a unique aluminum guard that covers the exposed knives. The fence is supported by the motor housing, and a lever locks it at the desired angle. With a direct-drive motor that spins the cutterhead, this jointer is still providing reliable service today, and originally powered direct current.

Below, a fragment of a 1917 patent application for the J D Wallace "Portable" Jointer

Basic considerations of how jointers and planers operate

On beginning a project, woodworkers face two major problems:

(1) cutting workpieces to their approximate size, and

(2) squaring and smoothing them.

You can achieve these goals in a number of ways.

Ideally, you can do this by combining the functions of power saws with, if you have access to them, a power jointer and a power planer.

Lacking a jointer and planer, you can use hand planes.

Jointer/Planer combo lacks manuals

-- one exception, Rick Peters' Jointers and Planers: How to Choose, Use, and Maintain Them , 2001

In preparing this syllabus, I consulted several authoritative manuals and articles, in particular the articles on the jointer in Shopnotes, issue no 48 (Nov 1999), Ernie Conover's articles on the jointer and the planer, American Woodworker, v. 1, no 3 (Sept 1985) and v. 1, no. 4 (Dec 1985), and the chapters on the jointer and the planer in Daniel W. Irvin, Power Tool Maintenance, 1971, Robert Scharff's The Complete Book Of Home Workshop Tools, 1979, William Holtrop and Herman Hjorth's Modern Machine Woodworking, 1960, and Consumer Guide's 1978 Tool Catalog, and Rick Peters' Jointers and Planers: How to Choose, Use, and Maintian Them , 2001, and R J DeCristoforo's Woodworking Mistakes and Solutions: Professional Secrets for the Homecraftsman. (Irvin's Power Tool Maintenance is a much sought after item by avid woodworkers -- viz Old Woodworking Machines website.)

(Conover's pieces are not that sexy -- the source is the original AW, under Jim Jenner's editorship, a much different beast than what we know today, when AW is owned by Reader's Digest. For one, there are no illustrations. I have on my computer's hard disk, copies of the AW stuff by Ernie Conover, and will send them via email -- ray@woodworkinghistory.com -- if you'd like to read Conover's comments on the jointer planer.)

"Romantic Heroes" vs "Unsung Heroes"

Unlike the bandsaw, the shaper, the router, even the table saw, the jointer and the planer are not currently graced with the sexy "how-to-use [it- fill in your own tool]" manuals. With the realization that currently not any manuals exist for these two essential tools, right or wrong, here's the analogy that immediately came into my mind: "romantic heroes" vs "unsung heroes". (Romantic heroes comes to mind because of that dismissive phrase, most often used by non-woodworkers, "Big Toys for Big Boys". The router is at the top of the "romantic hereos" heap; I myself own three routers, and have built my own router table.) 

For me, however, the jointer and the planer are the unsung heroes of woodworking. That's why, as my theme, quoted above, I chose "essential workhorses", to endeavor to express the idea that, regardless of their lowly status in woodworking, these tools perform essential tasks.

S-4-S

This presentation should begin, I think, with an analysis of several workpieces, each in a different stage of  the process, i.e., from rough-cut to squared and smoothed, required to create a component in a woodworking project. In the rubric of woodworking, it's called S-4-S, or "square four sides"

4-S-4

(A schematic of this operation is shown below.)

Taken together, these four examples, each at a different stage of the transformation from rough board into dimensioned workpiece, show both the compatibility and the essential versatility of jointers and planers (and tablesaw/bandsaw).

Then, treating the jointer before the planer, I divide each of the two sessions into the types of jointers and/or planers, including the typical prices of representative machines in each group:





Both sections on jointer and planers include

(a) the anatomy of each tool

(b) models of each tool

(c) analysis of each constituent part

(d) operation

(e) setting knives in jointer/planer cutterheads

(f) maintenance and tune-up

(g) accessories

(h) safety

Three additional sections are

(a) troubleshooting in planing

(b) summary of features to check in assessing the quality of a jointer and a planer

(c) the annotated bibliography directs you to numerous other sources

back to top

Jointer and Planer Ideal Combination

With a jointer, you can surface and square lumber accurately, i.e., S-4-S, and/or remove a workpiece's warp or twist. Other jointer functions include rabbeting, tapering, beveling, stop beveling, chamfering, and stop chamfering. But jointers work best when combined with planers and table and/or bandsaws. For the using the planer as acompanion to the jointer,  Ernie Conover says it best:


A jointer cannot stand alone in that it cannot make a second side parallel to the first, that is the job of the planer. Both machines are necessary to obtain flat S-4-S (surfaced four sides) lumber suitable for cabinet work.



4_S_4

Primarily used to dimension lumber to an exact size, the jointer's name comes from the use of two straight and square edges required to create a good glue joint.

With a jointer, you can surface lumber accurately, i.e., S-4-S, and/or remove a workpiece's warp or twist. Other jointer functions include

rabbeting, tapering, beveling, stop beveling, chamfering, and stop chamfering.

And, as you see in the diagrams above illustrating the sequence for squaring stock, a table saw is needed too.

Why the name "Jointer"?

checking for squareness




The jointer's name comes from the need for two straight and square edges (i.e., "joints") required to create a good glue joint.







back to top



Jointer Anatomy and Characteristics

jointer anatomy

Adapted from Willis H Wagner, Modern Woodworking, 1974, p 11-2

1.Infeed Table:

Called the infeed table, the "front" of the jointer is where the workpiece is placed, then "pushed" against the rotating knives in the cutterhead. The top surface of the table is ground "flat," its width determined by length of the cutterhead. Using a depth of cut scale, you adjust the depth of cut (8) with either a knob or a hand wheel.

The longer the table, the more capable the jointer is in accurately squaring a workpiece, especially a workpiece 3 feet or more.

back to jointer anatomy

2. Outfeed Table:

The "rear" of the jointer, where the workpiece slides onto as it passes through the rotating cutterhead, is called the outfeed table. The surface of the table is also flat, and its width the same as the infeed table. As a rule, except for professional models, the height of the outfeed table is not adjustable. Instead, its height is the same as the top of the arc of the rotating knives. Like the Infeed table, the longer the outfeed table, the more capable the jointer is in squaring stock, especially longer stock. (As I note in #6, on jointer, above) , if the outfeed table is adjustable, set it square with the infeed/outfeed table and leave it alone.

back to jointer anatomy

3.Electric Drive Motors:

Using a belt/pulley, the motor powers the cutterhead. On stationary jointers, Horse Power ranges from horse to 3 or 5 horses.

Benchtop jointers use universal motors and -- like the motors on routers and bench top saws -- a universal motor on a benchtop jointer is a mixed blessing. On the one hand, with variable speed, it allows you to control the speed of the cutterhead, which ranges from 8,000 to 16,000 rpm's, where the high speed allows fine jointing of hardwoods like bird's eye maple. The tradeoff is high-pitched noise.

back to jointer anatomy

4. Fence:

Working in conjunction with the infeed and outfeed tables, the fence is a vital part of the jointer for accurately squaring of workpieces. Most frequently the fence is secured at 90 degrees to the table. But, for giving workpieces different bevels and/or chamfers, say a 45 degree bevel, using a "tilt angle scale," (11) the angle of the fence can be adjusted. My preferred rule for such functions as chamfering, though, is use a router or shaper. Leave the jointer for its principle function, smoothing the surfaces of boards and squaring the board's edge with one falt surface. (4-S-4)

5. Dual Fence Control Handle:

The device for adjusting the angle of the fence.

back to jointer anatomy

6. Infeed Adjusting Hand Wheel

The device for adjusting the depth of the cut. Works in conjunction with the depth scale (#8 on jointer above). On normal work, depth-of-cut settings should not exceed 1/8". A 1/16", or even 1/32", setting is better, since such passes require less power and wastes less wood.

back to jointer anatomy

7. Outfeed Adjusting Hand Wheel:

Many jointers don't have this function, which reduces potential problems in using your jointer.

For me, most problems with a jointer (on my combo Robland X31) derive from the outfeed table getting out of its setting.

Only for some operation like champhering do you adjust your outfeed table. Otherwise it should be set perfectly level with the top of the arc of the cutterhead knives.

back to jointer anatomy

8. Rabbeting Ledge

If you have a rabbeting ledge  on your jointer, it serves its purpose usefully, i.e., creating a narrow rabbet along the "length" of a workpiece, although – as Ernie Conover notes -- it is potentially dangerous, so use the rabbetting ledge carefully.

9. Depth Scale:

Works in conjunction with the infeed adjusting hand wheel (#5 on jointer, above) .

back to jointer anatomy

10. Front Guard:

A safety device, this is a piece of metal on a pivot that covers the rotating cutterhead. (Evidently, guards are plastic on benchtop jointers.) The pivot, round, sets in a hole on the infeed table. As the stock passes through the rotating knives, the guard "rotates" on the pivot. As the workpiece passes beyond the knives, onto the outfeed table, a spring returns the guard to its position over the rotating knives.

11. Base:

See jointer models, directly below, for examples of jointer bases.

back to jointer anatomy

12. Tilt Scale:

Use a square to check for squareness. Don't trust the scale. However, after squaring the fence, tighten the fence (#4 on jointer above) firmly, and you'll probably be secure in maintaining an accurate joint. I do, however, check for square when I use the jointer after several days of not using it.

Jointer Models:

The first type of jointer, the portable,  benchtop model, is a small, lightweight tool that is easily lifted on or off a workbench. Benchtop jointers are lightweight because the base is often plastic or thin sheet metal. And, typically, the fence, the infeed and out-feed tables are made of aluminum. Shopnotes #48, an issue with excellent coverage of a range of jointer issues, discusses two options for extending infeed/outfeed table of benchtop jointers, one you purchase, the other you make. Prices range between $200 to $450.

benchtop jonter

Quite common, the heavier open-base jointer provides capabilities and dimensions  for the jointer that the benchtop lacks, i.e., abilty to smooth the flat surfaces of longer (narrower than 6 inch) boards, ability to cut rabbets. Another variation is the Enclosed Base. Prices range from $470 to $750. the photo shows my 1970s-vintage 6-inch model. Note that it lacks provision for a dust collection port.

open base jointer

Professional:

A jointer that you'd likely see in a professional cabinetmaker's shop, this type of jointer offers considerably more capability, e.g., stronger motor, longer tables, but these features come at a price. $800 to $1600, and on up.

professional jointer

Powering the Jointer

Using a belt/pulley or by direct-drive, the motor powers the cutterhead. On stationary jointers, with standard inductive motors, Horse Power ranges from horse to 3 or 5 horses. Benchtop jointers use universal motors and, like the motors on routers and bench top saws, a universal motor on a benchtop jointer is a mixed blessing. On the one hand, with variable speed, it allows you to control the speed of the cutterhead, which ranges from 8,000 to 16,000 rpm's, where the high speed allows fine jointing of hardwoods like bird's eye maple. The tradeoff is high-pitched noise.

back to jointer anatomy

Jointer Cutterhead Anatomy

(1)

cutterhead anatomy

back to top

Cutterhead Anatomy (2) (I found this in late 1940s issue of Home Craftsman.) hjorth jointer cutterhead

The "heart" the jointer and the planer is its cutterhead. Cutterhead configurations are of two, mostly three, and even four knives. Cylindrical in shape, the cutterhead secures the knives in slots. The cutterhead's length (i.e., width) determines the width of stock that can be flattened and smoothed and/or squared. Width varies from 4 inches up to 12 or even 15 inches. Diagram above is from Thomas W. Miller's "Setting Jointer Knives,"AW v. 1, no. 3 (sept 1985), p. 30.

Currently, jointer and planer cutterheads are cylindrical. It wasn't always that way, though. The original 1808 Woodworth machine used a "square head" design. The square head gets its name from the fact that the knives are bolted to flat spots milled on the head. Without the knives in place, the head looks square rather than cylindrical. Below is an illustration from the 1921 Oliver Machery catalog #21. For another picture, see figure 12, p. 16, of Herman Hjorth's Machine Woodworking, 1937.

In general, according to Conover, "the larger the diameter of the cutterhead, the better." Why? The large circumscribed radius leaves less of a rippling effect on the wood, and the feed rate and speed of the cutterhead should be so configured as to yield a minumum of about forty cuts per inch. Most machines sold today in fact, yield a minimum of fifty. The formula to derive this is: cutterhead speed times the number of knives in the cutterhead, divided by the feed rate, multiplied by twelve. This will yield the number of cuts per inch.

In number, usually 3, but sometimes 2 or more rarely, 4. Length of knives is determined by length of cutterhead. Constructed of steel or carbon.

back to top

Carbide cutterheads for jointer/planers

segmented section cutterhead

as featured in American Woodworker  sept 2005, pp 61-62. (My photos come from the showroom floor of the Grizzly outlet in Bellingham WA.) Rather than the standard HSS, this new cutterhead, labeled segmented carbide cutterheads (SCC) features numerous solid-carbide inserts. Evidently well-received, SCC are increasingly installed as standard equipment (I saw one the other day on Grizzly 's show room floor -- photo on right. ). Much of the material below is based on this AW article.

Currently these cutterheads run about $300 to $400, or even higher (I gulped when someone told me what he estimated SCC will cost for my combo.) When you consider the cost of sharpening HSS knives (about $15 a set) and the need for an extra set of knives to replace the ones being sharpened (about $30), maybe it isn't so expensive. AW claims that "the initial additional expense of a SCC is about the same as the cost for 20 HSS knife sharpenings," -- for me, this would be about 10 years -- meaning that eventually you will recoup your investment in SCC. With a SCC, AW argues, after your upfront investment, your payoff is immediate: "you get to enjoy all the benefits of carbide right away."

Insert Replacement Allow for Easy Knife Changes

With carbide inserts, knife changes are no longer such an onerous task (photo, page 62). No more fussing with knives that creep out of position as they're tightened down. After the inserts are dull, i.e, all four edges are used, they need to be replaced Curretly, depending on the number of inserts in the head and the cost of each insert, replacing the inserts cost ca. $120 to $200.

Changing Inserts

Generally SCC have ca. 40 to 60 individual carbide inserts. Inserts have four sharp edges -- when one edge becomes dull -- the next edge is rotated in. Rotating SCC is less frequent and doesn't have the anguish typical of HSS knives. This ability to rotate segments adds to the logevity of aset of SCC. Espereice suggests that a single set SCC of carbide inserts "will outlast a conventional knife set by approximately 40 times." Each edge will last up to 10 times longer than a typical HSS knife-edge, and, when you rotate each segment four times, the math makes that 40 times longer. Payoff: Carbide inserts will make clean cuts much longer than HSS knives will.

SCC Take More Power

SCC take more feed pressure and demand more horsepower from the jointer. this is need for more power, evidently is caused by the SSC always has several inserts cutting at any given time. A standard HSS straight knife has an "impulse cutting action," meaning that "each knife takes its cut, with a rest period between."

back to top

Advantages of SCC:

With SCC you can joint manufactured materials, such as melamine and MDF, which would instantly dull HSS knives , and hard, abrasive woods, like teak. SCC run noticeably quieter than HSS.

Barcke Knife System

Having wasted more time than I like to admit changing knives, I adopted the Barcke knife system. With the system, after an initial labor intensive job of drilling and threading THREE holes in each of the cutterhead's three slots, and screwing in and leveling the requisite 9 insert screws. Now, changing knives is a no-brainer. Changing knives consist of loosening the gib bolts enough to remove the knife from each slot, and -- since the knives have two edges -- flip each of the knives over and tighten the gib bolts.

Setting the Knives:

With use, jointer knives can become dull. After they are sharpened by a saw filer, the knives have to be reset in the cutterhead. To operate effectively, the knives need to be "set" so that they rotate at the same height, i.e., the top "arc" of the knives is the same level as the top of the outfeed table. fix link Click here to see the illustration in the cutterhead anatomy diagram. Otherwise, the surfaces of workpieces won' t be rendered uniformly flat. Setting the knives of a jointer can be time-consuming and frustrating. Just ask me. Frustration can be relieved, somewhat, by using a special jig, usually magnetic, designed to "hold" each of the knives at the same height as each is tightened in a slot. I have a commercial MagnaSet and some homemade jigs.

setting the knives

Basic Jointer Operation:

proper jointer operation

One the essential tools in any shop, professional or amateur, the jointer’s chief operations are dimensioning, flattening, smoothing and squaring rough workpieces. In addition, jointers can serve a wide variety of purposes, such as rabbeting, beveling, champhering, even creating dowels.

 
 
This sketch, from Shopnotes 48 (Nov 1999), shows the first step in a series of four steps needed to "square" a workpiece.

Steps in jointing a workpiece:

The sequence for squaring a rough-sawn board is the following: (1) holding the one thinner edge against the fence, “joint” one of the wide surfaces first, i.e., smooth and flatten. (2) Holding the just jointed wide edge against the fence, joint one thin edge. (3) Now, run the second wide surface through a planer.  (4) Finally, the second thin edge is cut parallel with the other edge with a bandsaw or table saw. Wood that is warped poses special problems, but a skilled jointer operator can dimension and square stock quickly.
 

Above  are some charts and diagrams on the recommended sequence of strokes/passes for squaring rough boards on jointer/planers. In addition, I have actual examples of squaring rough boards.

The chart with the 1,2,3, & 4 steps,  above , is adapted from Rick Peters' Jointers and Planers, 2001, page 43, but is repeated in most instances where a woodworker is describing teh steps for squaring stock to newbies. ( For example,  another treatment of this same operation is  "Five Steps to Foursquare Boards," in American Woodworker, May 2006. pp. 86-87.) 

back to top

This sketch (below, adapted from the Shopnotes 48 Nov 1999) shows why workpieces are either "thicknessed" in a planer, or -- using a tablesaw and/or bandsaw -- "resawn" so that both broad edges of a workpiece are parallel with each other. Thicknessing is an awkward term that refers to the process of making a workpiece equal thickness throughout. 

 

jointer operation 2

            Changing Knives:
 

When shopping for a jointer, consider the ease of changing knives. Just like the bandsaw, it is not as quick and easy as changing tablesaw blades. The following account off changing planer knives is a much abbreviated version of Shopnotes 48 (nov 1999), pp. 22-23:

When you change a jointer knife (and in many cases the same can be said about the planer), you must do the following eight tasks: 

  1. disconnect the tool from its electrical source;
  2. remove one knife (because it's wisest to only work on one knife at a time) by loosening the gib bolts;
  3. lift the knife and the gib out of the slot;
  4. clean knife, slot and gib with a recommended cleaning solution, and consider whether resharpening is needed;
  5. install a sharp knife by slipping the gib into the slot in the cutterhead, then slip the knife between the gib and one side of the slot (knife's bevel facing the outfeed side);
  6. with knife in place, tighten the gib bolts until knife is snug, but not tightened;
  7. adjust height knife (easier said than done, though, as doing this for three knives can take hours) and tighten; and then
  8. reconnect tool to power.

back to top

Maintenance and Tune up:

For older jointers, vintage 1980s, 1970s or earlier, Ernie Conover's articles, Herman Hjorth, both 1937 and 1960 eds, and especially Daniel W. Irvin, are recommended and all are listed in bibliography below. For later models, I recommend Shopnotes 48 (November 1999),  chapter 6 of Rick Peters, jointers and planers: how to choose, use and maintain them, 2001 and R J Decristoforo, Woodworking Mistakes and Solutions, 1996

show peters chapter 6

Safety:
 

Adapted from page 179 of Robert Scharff, The Complete Bool of Home Workshop Tools. McGraw-Hill, 1979

  1. never run a workpiece shorter than 10 inches across the jointer. Use hand planes on small parts, or surface the stock before cutting it to length.

  2. use a push stick when surfacing stock thinner than 3/4 inch -- for anything thinner than 3/8 inch thick, tape the workpiece on a larger board with double-faced adhesive tape, and then run it through a planer.

     

  3. keep your hands on top of the work, and, except for large workpieces, use a hold-down  -- keep the workpiece firmly on the table, against the fence.

     

  4. keep knives sharp -- dull knives cause kickbacks, especially when edging short or angle-cut workpieces.

     

  5. use the safety guard -- on some jointers, the guard cannot be employed when rabbeting or stop chamfering.

     

  6. before using a jointer, check to be certain that all parts of the machine are locked securely; especially the cutter-head knives. Never adjust the fence while the machine is operating.

     

  7. avoid deep cuts -- one-sixteenth inch is a good rule -- overcutting can cause kickbacks -- the only exception is when cutting a rabbet.

     

  8. do not run a piece across the jointer until the machine is at full speed.

     

  9. always try to plane in the direction of the grain -- never plane the end grain of narrow stock (less than 8 inches) -- surface the concave (hollow) side of a warped board first.

     

  10. stand at the left side of the cutterhead -- never stand at the end of the front table, because a board may accidentally kick back -- keep the floor around the machine clean and clear of scrap wood.

     

 

Planer Anatomy and Characteristics:

Either a stationary or a portable tool, the "thickness" or surface planer is designed to (1) make the broad surfaces of a workpiece flat and smooth and (2) an even thickness throughout it's length.

Types of Planers:

back to top

Portable Planer

Designed to be light enough to be picked up and carried, portable planers are ideal for taking to jobsites. Rather than the bed being adjustable, in portable planers, the motor adjusts up or down to accommodate the workpiece. Most portable planers will handle material up to 6 inches thick by 12 inches wide. Driven by a high speed universal motor, they have in my experience, a tendency to produce “snipe” if proper support on the outfeed is not provided. (For note on universal motors, see “Electric Drive Motors” in jointer section, above.) My own experience with portable planers is slight, having purchased one for a single project, and then, after I purchased my current planer, and finding that I didn't use it, let a friend use the portable planere on a “permanent loan” arrangement. Prices range from $200 to $450.

back to top

Planer- Molder:

Dual-purpose machines, planer-molders both function like ordinary planers also will cut custom moldings from plain workpieces. The planer knives can be interchanged with knives with different profiles (on left side, below), to cut an infinite number of different types of moldings. On right, below is a picture frame profile coming out of a molder. Woodtek lists a 13” planer/moulder at $540. This is NOT a recommendation, however.

molder-cutter

moler cutter 2d example

The planer's internal mechanism:

back to top

This illustration is adapted from p. 11-10 of Willis H. Wagner Modern Woodworking South Holand, IL: Goodheart Willcox, 1974.

internal anatomy of a planer

The rotary head of planers dates from the William Woodworth pattern of 1828. According to Ernie Conover (AW, Dec 1985, p. 7), "This basic patent was for planing wood by forcing a plank under a high speed revolving cutterhead with feeding rollers." The internal mechanism of a stationary planer is complex, and I give minimal details here. More details on Woodworth and early planers are given in Hjorth's chapter 1, in both the 1937 and 1960 editions (of the two editions, the 1960, listed above in the caption for planer's internal mechanism -- William F. Holtrop has become senior author -- is the more recommended) but for a more up-to-date account, use Irvin (fully described in bibliography at end).

Knives

In general, see jointer knives above. High-speed steel and carbide knives exist on the market for all machines. High-speed steel are least expensive while carbide will last longer. For combination planer-molders a myriad of different knives and standard and custom profiles are available.
 

Cutterheads
 

See comments above on cutterheads for jointers.

 

Bed Design
 

The distance between the cutterhead and the bed controls thickness of the material being planed. Most planer designs today use a configuration in which the bed moves up and down under the cutterhead. (The planer on my Robland is an example of the up-and-down operating bed. Evidently, besides the portable jointer, with the universal motor, there are a few designs in which the cutterhead moves up and down.)

 

back to top

Bed Rollers and Feed Rollers
 

These details are too technical for a brief overview like this, but important, if you own a stationary planer with bed and feed rollers. Consult Conover or Irvin, cited in bibliography below.

Chippers And Pressure Bar

These details are also too technical for a brief overview like this, but important, if you own a stationary planer with bed and feed rollers. Consult Conover or Irvin.

Motor (Horsepower)

Most twelve inch machines need a minimum of three horsepower and, if they lack bed rollers, five. Machines in the eighteen inch range need a minimum of five horsepower and more if they have babbet bearings or driven bed rollers. Machines in the twenty-four and thirty-six inch range need seven and one half to ten horsepower minimum. (Adapted from Conover, 1985.)

Portable or benchtop planers have universal motors. For more on these motors, see, fix link Powering the Jointer".

Planer Knives


 

In general, see comments above on jointer knives. Evidently, using a small grinding machine positioned over the cutterhead, planer knives can be sharpened while remaining in the cutterhead; however, see Conover’s discussion of the drawbacks using this method.

Feed Rate And Speed
 

Much debate exists about the necessity of variable feed rates, rates of feed, and cuts per inch. Complicating the picture, all of these components are interdependent, and vary greatly with the diameter of the cutterhead. (Above adapted from Conover, 1985.)

back to top

How Not to Use the Planer

how not to use a planer

The image above shows why you need to surface one side and one edge of a workpiece, for the 90 square angle on the jointer, before using the planer, for the 2d wide side. Remember Conover's rule: S 4 S.

I saw Scott Phillips on his TV series, “American Woodshop”, kcts-tv, recommend this method for surfacing and squaring walnut to millions of viewers.

Cutterheads

Like the jointer, the heart of any planer is its cutter-head.

Cutterhead configurations are of two, mostly three, and evidently, four knives. (Now, with  fix link segmented carbide cutters just coming into the market, cutterhead configurations are changing again.) Currently, planer cutterheads are cylindrical, similar to the jointer’s cutterhead. The original 1808 Woodworth machine used a “square head” design. (The square head gets its name from the fact that the knives are bolted to flat spots milled on the head. Without the knives in place, the head looks square rather than cylindrical. For a picture, figure 12, p. 16, of Herman Hjorth’s Machine Woodworking, 1937.).

Bed Design

Most planer designs today use a configuration in which the bed moves up and down under the cutterhead. (The planer on my Robland is an example of the up-and-down operating bed. There are a few designs in which the cutterhead moves up and down.) The distance between the cutterhead and the bed controls thickness of the material being plane.

back to top

Bed Rollers and Feed Rollers

These details are too technical for a brief overview like this two-hour session, but is important, if you own a stationary planer with bed and feed rollers. Consult Conover or Irvin.

Chippers And Pressure Bar

These details are too technical for a brief overview like this two-hour session, but is important, if you own a stationary planer with bed and feed rollers. Consult Conover or Irvin.

 

Feed Rate And Speed (directly from Ernie Conover)

There is much debate in the industry today about the necessity of variable feed rates, rates of feed, and cuts per inch. Complicating the picture, all of the factors are interdependent on each other and vary greatly with the diameter of the cutterhead. Of necessity, we have to speak in generalities, but it is safe to say, "the larger the diameter of the cutterhead, the better." The large circumscribed radius leaves less of a rippling effect on the wood, and the feed rate and speed of the cutterhead should be so configured as to yield a minumum of about forty cuts per inch. Most machines sold today in fact, yield a minimum of fifty. The formula to derive this Is as follows: cutterhead speed times the number of knives in the cutterhead. divided by the feed rate. multiplied by twelve. This will yield the number of cuts per inch.

 

Now. we come to the controversy over variable rates of feed. Although this is certainly a nice feature to have. I'm not sure it is something that should negate the purchase of a particular planer. Generally speaking. performance optimizes at the parameters we have outlined above, and greatly reducing the feed rate only hits marginal increases in finish quality. It is a feature that can be useful to someone who constantly works in very exotic woods.

 

Motor: Horsepower: (directly from Ernie Conover)

Most twelve inch machines need a minimum of three horsepower and, if they lack bed rollers, five. Machines in the eighteen inch range need a minimum of five horsepower and more if they have babbet bearings or driven bed rollers. Machines in the twenty-four and thirty-six inch range need seven and one half to ten horsepower minimum.

 Portable or benchtop planers have universal motors. For more on these motors, see, “fix link Powering the Jointer” in jointer section above.

 Planer Knives:

In general, see comments above on jointer knives, including comments on the new segmented carbide cutters. Evidently, using a small grinding machine positioned over the cutterhead, planer knives can be sharpened while remaining in the cutterhead; however, see Conover’s discussion of the drawbacks using this method.

 

 Maintenance and Tune up:

  • Tune up of any given machine is covered in the owner’s manual. This process usually includes: adjusting infeed and outfeed table heights to be in line with the inner table adjusting or changing knives and replacing the motor brushes if needed.

  •  Dust Collection systems will remove most dust and chips planers produce, but the remaining debris must be removed, most easily with a blast of air from a compressor, but vacuuming is another method that works.

  •  For lubrication, follow what the owner’s manual recommends. Usually, these are gears and chain, roller bearings, height adjustment mechanisms, cutter bearings but  some motors also need lubrication.

  •  The motor’s brushes also need periodic checking and the manual will show how to assess the wear and decide if replacement is necessary.

 

Accessories:

New planers feature dust collection ports, and after-market DC accessories can be purchased for most machines. And, according to Conover, most older machines can be retrofitted with infeed and outfeed rollers.

  Knives  (for planer-molders)

For combination planer-molders a myriad of different knives and standard and custom profiles are available.

Safety:

Because the thickness planer is a self-feeding machine:

  • Keep hands at least 12 inches from the blades and

  • Do not wear loose clothing.

  • Disconnect machine before doing anything inside it.

  • Wear safety glasses and hearing protection.

  • Clear the areas in front of and behind the machine to eliminate tripping.

  • Make sure sufficient room exists beyond the machine for workpiece to discharge.

  • Make sure there are no nails or screws in the board.

Summary of features to check for the quality of a jointer and a planer

 

Assessing quality: For both these tools, quality of parts and construction are important for lifetime of continued accuracy. Except for motor and belts, all parts of jointers and planers (except for portable planers) are usually steel (cutter head and knives) and cast iron (tables and fence). 

 

One of the best ways to judge the quality of a jointer/planer is the smoothness of its operation. This is especially critical when choosing whether to purchase a used machine. True, jointers have less rotating parts, which means less likelihood of problems. However, worn bearings in cutterheads could be a problem. Check for the signs of previous owner’s neglect or abuse, by noting unusual wear on pulleys and belt, the condition of the heads gib bolts, the motor mounts. All of these could display signs of neglect.

 

On planers, because the internal workings of a planer are much greater in number and more complex than the jointer, and  -- because of the planer’s enclosures, difficult to examine -- many potential problems can be more difficult to detect.  Review the points that Irvin specifies in his “troubleshooting the planer,” above. Like  Lonny Bird’s observation about  bandsaws planers  have more rotating parts than most woodworking machines—chains, rollers, and pulleys—and,  if the planer is going to run smoothly, these parts must be trued and balanced. Working with a vibrating planer is unnerving.

Operate the planer by planing different types of workpieces. Are the results satisfactory? If there are signs that suggest repairs or replacement parts are needed, would making these adjustments be easily achieved?

 

Finally, consult the Irvin manual or some of the other sources listed in bibliography.

 

Annotated Bibliography for both jointers and planers

Anonymous.  “Tool Review: Jointers” Shopnotes, issue no 48 (Nov 1999). Pp. 12-15.

In what for me is the best Shopnotes issue ever, this article details benchtop, open base, enclosed base, and professional jointers available today. A good companion to the Tool Catalog below.

 

Anonymous.  “Tuning Up a Jointer” Shopnotes, issue no 48 (Nov 1999). Pp. 20-23.

Covers jointer anatomy, parallel tables, adjusting outfeed table, setting  knives, fence, guard, and drive belt, setting knives with the  magnaset.

Anonymous.  “Jointer Extension Tables” Shopnotes, issue no 48 (Nov 1999). Pp. 24-25.

Anonymous.  “Benchtop Jointer Stand” Shopnotes, issue no 48 (Nov 1999). Pp. 26-29.

Using good color illustrations these articles lay out methods for extending the limited dimensions of infeed and outfeed tables on benchtop jointers and creating a “benchtop jointer stand”.

Marc Adams, "Power Jointers" Popular Woodworking February 2008, pages 41-56

Illustrated with color photos, this extensive article is a "must read" -- to use a much over-used cliche -- for any newbie woodworker seeking to master the jointer. Updates the earlier article in AW by Ernie Conover.

Conover,  Ernie. “Jointer Buymanship”  American Woodworker, v. 1, no 3 (Sept 1985), pp. 12-14.

 

Conover,  Ernie. “The Answer” [on the jointer and the planer]  American Woodworker, v. 1, no. 4 (Dec 1985),  pp. 7+.

In today’s amateur woodworking, Conover is one of our icons.  Both a professional woodworker and teacher, Conover has contributed numerous articles to virtually all woodworking magazines. He seems to have been a “founding member” of American Woodworker, but is not associated with it now.  Dated though they may seem,  I recommend these articles for woodworking buying a used jointer or planer.

DeCristoforo, R J. Woodworking Mistakes and Solutions: Professional Secrets for the Homecraftsman. New York: Sterling, 1996.

It's puzzling why DeCristoforo does not touch on planers in this otherwise superb guide to power tool alignment, wood surface preparation, and "troubleshooting"

Gibson, Scott. "What Size Jointer Do You Need?" Taunton's 2006 Tool Guide, pp 72-73.

Gibson, Scott. "Choosing a Planer" Taunton's 2006 Tool Guide, pp 78-79.

The article on jointers is ery brief,  with 6 photos, detailing features to consider when deciding which jointer to purchase. The same issue, on pp. 78-79, covers planers, with attention briefly ddirected toward the jointer/planer combo machines, somewhat pricey, but well-designed and reliable, and -- what can be important -- having a smaller footprint, for smaller-sized shops.

 

Huey, Glenn. "The Right Way to Prepare Lumber", Popular Woodworking November 2006, pp. 70-74.

In the tradition of  Ernie Conover (whom I mention frequently above), this article combines text and photos. "To true your wood with machines, the steps you follow are critcal. This time-tested procedure is the best way we know of.

The following titles cover both jointers and planers:

Consumer Guide. Tool Catalog, Harper,  1978.

You might call this a “sleeper,’’ because at first glance it looks like an over-commercialized, ephemeral book, designed to appeal to the newsstand purchaser. However, it definitely has lasting depth, and should be in our ncwa library. Helping to give this volume its lasting value, among others, are contributors like Ernie Conover and R J Decristoforo. Both hand and power tools are covered in its 8 chapters, and anyone buying a major stationary tool vintage 1960-1970 wisely should  consult this volume for recommendations. Lucky, I bought a used copy for $12 at Michael’s Books in downtown Bellingham. 

 

Irvin, Daniel W. Power Tool Maintenance. McGraw-Hill, 1971.

The most sought after manual for the maintenance of all major stationary woodworking tools. Twenty-two chapters cover belts, pulleys, bearings, lubrication, motors (wiring and controls), parts and service info, all major stationary woodworking tools, and portable electric tools.

back to top

Hjorth, Herman Machine Woodworking. Bruce, 1937.

Hjorth taught woodworking during the middle decades of the last century in the Bronx. Chapter 1 focuses on the historical development of major stationary woodworking tools. Provides bibliography, but does link discussion to sources. I have the 1960 ed.

 Scharff, Robert. The Complete Book Of Home Workshop Tools McGraw-Hill, 1979

Similar to the also dated catalog (above), but still useful, this book helps amateur  woodworkers select and use hand and power tools in the home workshop. Describes the tools, explains how to use them correctly and safely and how to care for them.

If you’re interested in more of the  historical background on the development of the jointer or the planer, check out this page on the Old Woodworking Machines website: http://www.owwm.com/MfgIndex/detail.asp?ID=919. Chapter 1 of Herman Hjorth’s 1937 and 1960 editions of  Machine Woodworking are also useful. WWU has a copy.

FW issue no 160 review of 12 inch planers (portable or stationary?)

FW issue no 160 thicknessing rough lumber

Jointer Tune-Up http://www.plansnow.com/tuneupjointer.html

Frustrated with your jointer? Tear-out, scoops, dishes, and humps in your stock are clear indicators that your jointer may need a tune up.

back to top