When to shape and when to route?

[Ollie]

Today I got a router bit spindle for my simple shaper - no sliding table nor power feed. I have some router bits, mainly 1/2" shaft. There are many shaper cutters that are the only choice for a cut, such as glue joints or double lock miters. Then there are some cuts that you could do either by shaping or routing. Is there a simple set of "rules" that would help me to decide when I should invest on router bits, shaper cutters, or both? My main interest is in the accuracy and quality of the cut and secondary interest is in the safety of the cutting operation.

Some counterexamples would be nice to know for cases where in theory, you could do the cut by shaping but routing is the right choice and vice versa.

Cheers, Ollie

[eganders]

This is a good question, because except for real large jobs, I can't imagine not being able to use a router for most anything a shaper can do. Your statement about a lock miter. For 3/4 stock couldn't you use the lock miters just a well that are made for routers? It would seem that height, depth, speed and the ability to take the punishment for hours, days and years are the forte of a shaper. For me and most other "weekend warriers" a router should do the job--right?

[George]

Smaller the diameter of the bit, the more you need the router's speed.

Larger the diameter or more frequent the cut - the shaper.

[Lowell Holmes]

I have both. There are some jobs that the shaper does better and safer. Cope and stick doors are one of the tasks favoring the shaper.

Tongue and groove molding is a shaper job.

By the time you buy a 3hp router, build a precision router table, and add all of the guide fences and gadgets, you've exceeded the price of a Grizzly shaper.

My shaper is a Rockwell. My routers are mostly yellow, but I do have a PC690 in an extension table on my CS. It just is not as precise as the shaper with its ground cast iron table. The height adjustment on the shaper is quick and stays in place, it doesn't creep like the 690 will. I've never had the motor and arbor fall out of the shaper while shaping. I have had the router fall out. Fortunately, I had the router on a foot switch and was able to avoid damage or injury. I'm sure if you use one of the height adjusting mechanisms on the router, that wouldn't happen, but that sure puts the cost up above the cost of a shaper.

Not many agree with me, but that really doesn't matter. :-) As with other issues, go with what ever floats your boat.

[Andy Dingley]

If you _have_ a spindle moulder (shaper in the USA) then use it for everything. If you don't have it, don't use it.

A UK "shaper" is a different machine. Size and speed of a moulder, half the price (so still more than a router) and a collet to take router-style bits. I've never seen the point of these machines. They're not as capable as a moulder and they're too slow to leave a good finish with router-sized tooling.

The awkward question is when to buy your first spindle moulder. Usually this is because you _need_ a particular large cutter that's impractical for a router, even if you then spend most of your time using it with a different cutter, which you could have run in a router.

[Mark & Juanita]

ayup -- Woodtek shaper in my case. Turned out a tad more expensive because I added the sliding table -- but that would have been rather difficult with a router table.

One of those not many who does agree with you, for pretty much the same reasons you listed above, except I haven't had a router fall out of the table -- yikes!

+--------------------------------------------------------------------------------+ The absence of accidents does not mean the presence of safety Army General Richard Cody +--------------------------------------------------------------------------------+

[Ollie]

Thanks for all the good advices and scary stories, but I am still missing the actual insight to this matter. The question was not in comparison between shaper and router. I have a separate router with three different settings (plunge, D-handle, and the fixed head) for all from-the-top operations. The question was about the bits and cutters used in the shaper

It has three spindles that can take the shaper cutters with 1/2", 3/4", and 1" round bores. With the add-on part (router bit spindle), I can use router bits with 1/4" and

1/2" round shafts.

The question was, when to use the shaping cutters and when to use the routing bits in the same machine. For example, you could cut a 3/4" wide dado from the side using a cutter head, such as Amana 912

or from the bottom using a straight plunge cutting router bit, such as Amana 45440 Obviously the spindle travel, such as 3", is a limiting factor for some shaping cuts. In some cases, the shaper table size is not large enough and you have to use the dado blade in a table saw. The essence of the question is for those cases, where you could do the same cut either by shaping or routing. For example, there could be some reasons to use a cutter head for shallow dados and a routing bit for deep dados. What are the resons for dado cuts? What are the resons for other cuts?

All comments are highly appreciated, Ollie

[Morris Dovey]

A simplistic response: For those cuts you'd make at or slower than 10,000 RPM with a router, use the less expensive bit. If

10,000 RPM is too slow for a router cut, use the (generally larger diameter) shaper cutter.

You might find it helpful to DAGS on 'router chip load' - which is one of the relevant tool factors (others are feed rate, spindle speed, and cutter geometry) - and, of course, the material being cut has considerations of its own.

These days my shaper sits idle and a 5HP router does the work. For most of the work I do, I run the spindle at 18,000 RPM and feed somewhere between 1-1/4" and 1-1/2"/second for burn-free cuts with a minimum of dust. I generally consider that I have things fairly well balanced when the routing operation produces chips (with a length equal to the depth of cut) rather than dust, and a nice clean edge with no burning.

Not sure I understand your last two questions - Cut a dado when your design calls for a dado. Cut something else (or not at all) when a dado isn't called for.

[Ollie]

Morris, thanks for the good info. I am still new in this business and the reference to DAGS was strange to me? What is that?

My question about the reasons for dado cuts was a short hand to ask "What are the arguments to do the dado cuts with cutter head and what are the arguments to do the dado cuts with router bits". Your answer indicated, that there are very few (perhaps none) reasons to use the cutter head if there is a router bit that can do the job.

Cheers, Ollie

[Morris Dovey]

DAGS: "Do A Google Search" (use the internet search engine at to find information)

Don't be in a big hurry to send the shaper to the dustbin! You may need it yet. Your needs are almost certainly different from mine; and at some point you may discover that you prefer the shaper for some of the operations that you do (and I do not.)

[Ollie]

Morris, good stuff.

I did dags the DAGS and observed that the acronym is used mainly in woodworking discussions - interesting. On other hand, I did find the following reference and still wondering what are dags.

Cheers, Ollie

as_is G'day.

Go here...

follow the links to contact them & ask for the demo video on CD.

In the mean time, speed up the lathe to around 500RPM & slow down the feed rate. (of the tool) Cliff, I eventually received a reply from Woodcut and the reseller. No clear answer regarding calculating depth of cut or even grabbing but they refer back to the brochure and sugegst a method of holding via spigots. I also have the video CD which I viewed several times. I have since slowed down the tool feed rate and hold the handle with both hands to prevent the tool from being dragged into the job thus jamming. I also deburred some of the edges of the tool which had plating

dags

and applied wax on the cutter. I will speed up the lathe next time. Thanks for the tip. I have also worked out from geometric first principles the depth and bowl radius and produced a guide table. Regards Alec

[Morris Dovey]

I dunno. The original acronym used to encourage people to do a web search was STFW (you can find a translation by DAGS :-) but these days DAGS is considered a bit more friendly/genteel.

The "g'day" in the quoted post may indicate the need for translation from Australian.

[George]

Answer's still the same.

Smaller the diameter of the bit, the more you need the router's speed.

Larger the diameter or more frequent the cut - the shaper.

If either tool is capable of doing the job, the shaper is favored for volume work. It's got thicker cutters, an induction motor, and is easily adapted for power feeding.