Question (WOODWEB Member) :
I got a small start with a Grizzly 1037z making runs of base, casing and crown but I have problems with the machine breaking down - new rollers, broken chain drive, etc. I want to upgrade to a Williams and Hussy. I bought my knives online for my Grizzly and now I have about $3,000 invested. I want to know the best process for making your own knives. Do you need expensive CAD software to design the plastic templates? How do you cut the plastic precisely? What is a good entry level profile grinder? Where do you buy the steel?
(Architectural Woodworking Forum)
From contributor F:
Molding knives are going to require some expensive equipment to do right. Basic small profiles can be ground down free hand on a regular grinder, but for wide knives like what you'll use on a W&H, I'm not so sure? Grinders are pretty pricey on their own, though I've occasionally seen them pop up used for several thousand. Then there's learning how to grind and all the geometry with grind angles and relief angles, etc. to get them to cut right. Plastic templates I believe are usually cut on a CNC. Though I'm sure you could do a single template by hand and get it close enough for most things. The steel is possibly the easiest part of the process. You can buy it from a company like CG Schmidt, or even shop around e-bay as they have it all the time. I'm sure you'll get a lot more info as others respond, but I'm thinking you'll have to be cutting a lot of steel to make it worth your while getting into making your own molding knives?
On the cabinet side I need the same signature moldings in birch, oak, alder, poplar so I need to be able to make small runs of molding. I have three inch tall corrugated molding head for the shaper. Most moldings are less than two inches but the crown I use on top of the cabinets is 3 1/4 larger than the shaper can handle. The crown I use for my mantles are 4 1/4. I did buy the shaper used but I rebuilt bit shaft from housing, bearings, inners housing, drawer bars. I not sure where to invest the money to keep the cabinets going?
I don't own a W&H style molder so I can't say a lot about them. My understanding is they're good for small molding runs but have a tough time removing a lot of stock from hardwoods in a single pass. A good molder like the W&H can make you money and is less of an investment than the bigger shaper, but it won't be as fast or be able to remove as much stock.
Then there's the way molding outfits run their stock. You get yourself a nice 4+ head molder and run the stock through doing most of the rough milling and molding in one shot. A good molder is far and away going to be the fastest and best quality of product. Of course it's also the biggest investment. You have to make sure you have enough dust collection, power, and room for it.
Personally for a small shop I think a good quality shaper is the best bet. A good Euro shaper is a flexible machine that makes it easy to go from stile and rail cuts, to moldings to beaded face frame stock with short changeover times. You don't need a whole lot of room or power for it. It's not as easy to run the wider moldings as a molder, but it can handle 4-1/4" crown when needed. Once you get a good shaper then maybe think about adding a W&H molder for the wider trim to keep things moving?