Woodworking shapers

Or should I use a router table?

Background

A few years ago I "retired" to full time woodworking. In the process I reconfigured my shop to allow me to work alone, more efficiently and safely, including purchase of a large European combination machine. I wondered what I was going to do with the 5 hp shaper that was part of that machine, other than being a substitute for the router table that I had built into the wing of my old table saw (sold to make room for the new machine).

Now that I have the shaper, and have invested in some good cutters, I am considering getting a second shaper... once you experience the power and precision of a shaper, there are lots of new opportunities.

Shaper vs. Router Table

I recently participated in a program for our local woodworking club, comparing router tables to a "basic" shaper, with the idea that a basic shaper may be a better, more economical, alternative to a table mounted router. Three different "good" router table configurations were considered, and compared with four different shapers. In the comparison, all prices were "every-day" prices - by waiting for a special sale, any of the options may be cheaper.

The first router table configuration was a club member's home-made system, based in part on the New Yankee Workshop router table. The router was a PC 7518 with no base ($325.99), a commercial lift system that was added ($289.99), and materials to build the table that brought the total to $838.98

The second system was a commercial table, installed in the Woodcraft classroom where the club meets. It also consisted of the PC 7518 router ($349.99), a commercial lift system ($289.99), and the Kreg Precision Router Table (that includes a steel table, top, and fence) for $499.99, bringing the total to $1,139.97

The third system was a basic bargain system. The router was the Hitachi MVP 12 - assuming that a high power variable speed unit would be required - initially or eventually ($249.99), a base plate to mount the router in a table, no lift system or precision fences, and an estimated $85 in materials for a basic cabinet, for a total of $384.98.

The shapers needed to be compared on the basis of features, not just components. Comments about many of the features appears below the table.

Power: Most routers use the lighter universal motors (with brushes). The rated power and speed cannot be sustained under continuous load. Most shapers use induction motors, a heavier motor common in fixed machines, but with more consistent power output and speed. Any motor consistently producing over 1½ horsepower cannot normally be run on a household circuit - the higher power motors require 230 volt power.

Spindle: A wide variety of shaper cutters are available for a ¾" spindle. The commercial grade cutters generally require a 1¼" or larger spindle. The common metric size cutters require a 30mm spindle, close to the American 1¼" size.

Maximum Cutter under nut: How tall a cutter, or combination of cutters, can you use at a time. Some people like to mount both rail and stile door cutters at the same time, and simply change the height. A rub ring (bearing, guide bushing) adds to the height. I recently bought a 2 inch high cutter to trim along a pattern. With spacers and the bearing, the combination was close to 3 inches. I had considered a 3 inch high cutter, but it would not have fit on my current shaper.

Vertical travel: This is important if you want two cutters mounted simultaneously, or if you want to use a cutter for part of a larger profile.

Router Spindle: Router bits can be used in a router collet or a separate router spindle on a shaper. This allows existing cutters to be used, or use of specialized profiles that may only be available for a router. Normal router speeds are about 18-25,000 rpm, but larger cutters must be slowed to 10,000 rpm. Most shapers cannot go faster than 10,000 rpm, which is adequate down to about a 1/4 inch roundover bit; anything smaller I switch back to the hand-held router.

A router bit designer warned me about the "slow" 9-10,000 rpm on normal router bits... I made the argument about "just feed slower." He pointed out that the cooling of the cutter worked by the chips carrying the heat away, and with the slower speed, the chips wouldn't be thrown as well. Therefore watch out for burning with the slower speed and slower feed rate. (I haven't had a problem, but I watch for it, or for cutters getting hot).

Shaper Speed: Just as a router needs to be slowed (to perhaps 10,000 rpm) for larger router bits, a shaper needs to be slowed for the larger shaper cutters. This is often done by moving a belt on the drive pulleys.

Reverse: It is common to occasionally mount a shaper cutter upside down, reverse the direction of rotation, and reverse the normal direction of feed. This makes other parts of a shaper cutter accessible, and allows work to be fed face up rather than face down (or vice versa). Some shaper spindles also tilt to expand the opportunities with cutters. There are arguments (and very strong opinions) whether a forward or backward tilt is better, but inverting the cutter and reversing rotation gives the profile opportunity that the "other" tilt might have offered.

Dust Collection: Some shapers have a separate dust collection port for chips that are thrown under the table, in addition to those thrown into the hood behind the fence.

The first three shapers might compare favorably with a router table, but as a committed shaper user, with quality shaper cutters, I found the fourth shaper quite attractive.

Power Feeder

A constant feed rate, with consistent pressure of the work against the fence/cutters, allows the shaper (or router) to give the best quality cut. Power feeders are often used with shapers - the wheels of the power feeder straddle the cutter, and provide the pressure in addition to the movement. The control provided by the power feeder allows climb cuts when that would be preferable.

A real world example. I have a large router bit to create crown mouldings for furniture. When used in a router table, a significant amount of sanding was required. The same cutter in a shaper produced smoother cuts, with far less sanding required, apparently because of the heavier table and larger bearings reducing vibration. When the power feeder is used, even less sanding is required.

It doesn't seem like much power should be required in a power feeder. Not true. I have a "small" ½ hp power feeder, which I now consider barely adequate. If you are considering a feeder, be sure it has multiple speeds, forward and reverse. The mounting arm, with multiple pivot points, needs to be very strong, and may weigh 100 pounds or more.

Cutters and Accessories

Tenons

European safety rules prohibit non-through cuts on a saw (which also rules out dado blades). Therefore European woodworking practice is to cut tenons on the shaper, rather than the American tradition with a saw. A 1 inch long tenon might easily require a 4 inch diameter cutter (or two cutters with a spacer, to cut both sides of a tenon at the same time. Since the cutter tries to pull the work into the blade, special fences and/or jigs are required to control the workpiece.

Cabinet Doors

A modest quality rail and stile cutter with braised carbide tips might cost $80 for a one or two piece set, with high quality carbide tip cutters going up in price from there. Some would argue that a cutter with "insert" high speed steel cutter tips might be better. A top of the line rail cutter with replaceable carbide tips (that I bought from DeHart USA) cost $375 (but a set of replacement carbide inserts are only $75). The stile cutter was an additional $375. Despite the "take your breath away" price, now that I am over the sticker shock, I consider it a good investment because of the extremely smooth finish and precise cuts.

A modest panel raising cutter with braised carbide tips might cost $80, with better quality cutters going up in price from there. The same cutter can be used as a "back cutter" if required, or a dedicated back-cutter can be purchased. A separate bearing is required for curved top doors. The "top of the line" panel raiser, with bearing and dedicated back cutter (the three are stacked together on the shaper), with replaceable carbide tips, like above, cost $1,150.

Pattern Routing

I recently bought a Byrd Shelix head with guide bearing to use for pattern routing... FAR better than router bits, even 1 inch bits in the shaper, because of the larger diameter cutter and bearing.

Sanding

I know some people who get a sandpaper spindle for their shapers, for sanding curved surfaces.