Moulding Cutters for a Shaper
A newcomer seeks advice on tooling up to make mouldings on a shaper. In a long discussion, pros explain some of the options. August 31, 2005
Question
I have been trying to find shaper cutters for base molding and have not had much luck. I have no desire to spend tons of money on a dedicated molding machine, especially since I can't see why I couldn't do this with a shaper. Do I have to use insert tooling and grind my own profiles? I am beginning to think it would just be easier and cost less money to go buy the crap at Home Depot.
Forum Responses
(Solid Wood Machining Forum)
From contributor R:
I do this all the time on a 7-1/2 hp shaper. I have custom profiles as well as knives made to match old mouldings, base, crown, casing, you name it! You should buy corrugated heads as you need them. I have 2", 4" and 6" heads as well as two lockedge heads and a head called the "Innovator" from Charles G.G. Schmidt Co. that I use for custom panel raising profiles.
I have my custom tooling made by Bull Sharpening. Schmidt also stocks common profiles and makes custom. This is a good money maker when reproducing short runs of an existing profile. Then you keep the tooling for anything in the future.
From contributor F:
I don't know what profile you are looking for, but a lot of the old styles of base molding were run on fairly wide stock, but only the top edge was molded. A lot of these profiles are similar and could even be run on a router table with a hefty custom router bit.
From the original questioner:
What kind of price range should I expect for custom knives? From what I've found so far, I'll end up paying almost as much for one set of knives (plus cutterhead) as I did for the shaper itself.
From contributor R:
For 1/4", 60 degree corrugated back knives, I pay $50.00 - $60.00 a lineal inch for two pieces. So if you have a std. two-knife head 4" tall, for most profiles (if not too complex or unusually deep), you should pay $200 - $250 or less. I charge the customer the knife fee for any custom profile I make, unless it's one I simply choose to make because I want it. In the 2001 Schmidt catalogue, a two-knife, 4-1/4" colonial crown is priced at $169.00. The head will cost $225 - $250 for a 4" tall, 1-1/4" bore. For a crown profile, you will also need a knife set for the angled back cuts (if you are smart, you will have one set of cutters made with the standard 52 degree on one edge and the matching 38 degree on the other edge and flip the head over to cut the second edge). These you will use for all standard 38 degree crown angles, regardless of the width of crown. Once, the customer asked to keep the knives because they had paid for them. Now I figure the price into the first run of millwork so that the knives stay in my shop.
I charge $1.25/l.f. to blank out the lumber and straighten if needed, and an additional $.25/l.f. for each profile cut I make to create the moulding. In the case of a crown, you have a face and two edges to cut, so $1.25 + $.75 = $2.00/l.f. I make good money on this for what I call "short run millwork" (under 300 l.f.). Anything over that, it gets to be more cost effective to order from a millwork shop.
From contributor A:
Template Services, Inc. has just added a bunch of base moulding profiles to our website. Please feel free to get some ideas from them. Although some guys grind their own knives by hand, most of them have a Powermatic, RBI, or Belsaw type moulder-planer combination where they use counterweights instead of subsequent knives. I don't think I've heard of anyone doing it for a shaper. Not impossible - one thing to consider is that your knives would have to be a fairly close match to one another and they would have to be balanced to within 1/10th of a gram. Very dangerous to run unbalanced knives on a shaper.
From contributor T:
With your budget and application, insert tooling is the way to go. You don't need the price tag of grinding and sharpening (possibility of distorting the profile, etc.). Many places can equip you with this setup. When the inserts get dull, throw new ones in.
From Dave Rankin, forum technical advisor:
If you have a corrugated head for your shaper, I strongly recommend the use of ground to pattern knives. The cost is around $20-24 per lineal inch. You can either use two knives or in some cases, you can use a balance knife. It is better to use two profile knives that are balanced.
If you run less than 2000 lineal feet with a shaper, HSS tools will work well. If you run 2000-10,000 lineal feet, you should use DGK knives. If you are going to run this profile over and over, you can consider insert tooling. In this case, I would use a universal profile shaper head. If you need assistance in determining which is right for you, contact your local tooling distributor or contact MSI.
From contributor C:
CMT has a very inexpensive insert shaper set that has nearly 200 different profile options available. They offer 13 piece sets and also sell cutter bodies separately. There are both 40mm and 50mm wide profile cutters available to do the profile part of the base moulding. The replacement knives are between $20-$30 per pair. You can access pictures of the individual profiles complete with dimensioned drawings, as well.
From contributor F:
It really isn't necessary to buy an extra shaper cutter to cut the back bevels on crown moldings. These can be easily cut with a sharp ATB table saw blade. These surfaces do not show after a molding is installed and if the cuts are smooth, it works fine. I know guys with the large production molders who routinely saw their bevels. Just make sure that the combined angle of the two bevels adds up to 90 degrees.
From contributor J:
Thanks for all the great responses. What is the difference between something like the CMT cutterhead and the Schmidt cutterhead? Looks like there is a big price difference. Is it possible to buy into one system that will allow me to make cabinets, crown moulding, custom patterns, etc?
From contributor R:
Although the CMT comes with ready-made tooling that is no doubt cheaper than custom, I find that there is a lack of visual quality and imagination to them. Historic millwork has a look of quality and grace that is missing in most off-the-shelf kits today. I like reproducing old millwork because of this. Typically, sets like the CMT are limiting, first of all, because the head is only maybe 2" tall. Second, it's very hard to use these sets to create a profile larger than one cutter that is appealing. If you get into the corrugated back tools, depending on the size of your shaper, you can work with a 2" through 6" head. When I started doing this, I purchased a 6" head because it gave me the most versatility. I could put a 2" knife in it or I could put a 6" knife in it. A set like contributor C shows will not make you a 4-1/4" crown. I have one of the multi-use heads and I never use it because the tooling that is made for it does not visually appeal to me. I just wouldn't worry as much about the initial cost as I would about what it is going to do for you. Remember that you will have the head or heads and knives forever and they should pay for themselves over and over again. Also, let the customer pay for custom knives.
From contributor F:
I have a planer style molder that I grind knives for with corrugated high speed steel.
Does anyone sell a shaper head for .25" corrugated that can be used with bearings for doing shaped edge work on the shaper?
From contributor C:
The earlier link I sent on the corrugated shaper heads allows you to make up to 6" long profiles (depending on the shaft length and horsepower of your shaper), using either 1/4" or 5/16" thick corrugated knives. Rub collars to match the diameter you need could be provided as well. I offered the CMT insert set as an additional option if the questioner is running short runs that would not warrant the expense of a dedicated cutter or having the corrugated profile knives custom ground for him.
From contributor F:
When you say "rub collars," do you mean they are frozen and spin with the head? Also, can you give a general idea of what a medium sized one would cost?
From contributor C:
A rub collar is a ball bearing with a metal guide ring press on it. It rotates on the shaft as your head moves. A rub collar in the 4" OD range runs around $75.00.