Four-Head Moulder Setup

Setting up a 4-head moulder to run flooring and mouldings. October 2, 2010

I purchased a Baker M412 moulder some months back, and am in the process of setting it up inside my shop. It will be primarily used to manufacture T&G flooring and boards for wainscoting panels, primarily from 3/8" thick stock.

I'm curious as to how to obtain the best quality on the machined surface, as I would prefer not to have to sand the machined surface (unless it is flat and can be sanded in a WBS). Flooring should not be an issue, but a bead or other profile in a wainscoting panel is a different story.

The Baker moulder comes with side cutterheads that utilize 2 knives. Yet most shapers use cutters that have 3, 4 or 5 cutting surfaces per head, which makes me wonder if the higher number of cutting surfaces results in a higher quality finish. Will I obtain a higher quality surface by purchasing side cutterheads that will accept 3 or 4 knives, instead of just 2 knives, or will the 2 knife head produce an acceptable quality surface that does not require sanding?

Forum Responses
(Solid Wood Machining Forum)
From contributor J:
2 knives are industry standard for non jointed moulders. Only one knife is doing the most work, even on a 3 wing shaper cutter. One downfall to a 4 head moulder is you don't have a "last bottom" head to do a finish pass. But you will be just fine. Floors get sanded really well after being laid and the finish off the moulder should be fine as long as you keep that bottom head sharp.

From contributor S:
With a 4 head, wouldn't you run good face up? So the good face isn't dragging down the bed of the moulder? 5 or 6 heads run good face down. I agree with contributor J - 2 wing cutter is fine, just play with your feed speed for the finish.

From contributor J:

Yeah, I guess you're right. It would make sense to run it that way. We run 5 heads but the guy (whose business we now own) we were milling for wanted a moulder dedicated to flooring available when needed. He bought a Northtech and we put it in our shop for his convenience. He had heads bored out for it and we ran flooring face down. I think your idea would have worked out better.

From the original questioner:
Guys, thanks for the info. Regarding good side face up versus face down, on the Baker moulder all of the segmented drive rollers are on the top. Theoretically, if I ran face side down I might be able to mill off less material from the good face, since I won't have to get rid of the marks from the feed rollers. I'll have to experiment with it to see what works best.

From contributor W:
Most people that run flooring run it face down/tongue out. This way feed roller marks are on the bottom of the material when installed and if it is scant in width, the depth of the groove is correct with a shallow tongue. This still allows the parts to go together and hold. The other responders are correct in stating that only one knife will be making a finish cut. Your finish will depend on how fast the spindles are turning and the feed rate. Of course more knives in a cutter take more horsepower to run.

From the original questioner:
That's great info and it makes sense. I'm going to stick with the original heads (dual knives). Thanks.

From contributor N:
If you are going to run flooring, I would go with an insert for your t&g and an insert spiral for your top head. Solid carbide insert for long life and repeatability.

From contributor O:
We occasionally run flooring and a lot of paneling on a 4 head. Face down and tongue out. We normally do a back out with the top head, so face down is the only choice on our machine.

From contributor J:
Contributor O's response reminded my why we ran it that way. It is recommended to have a back out or relief on the underside of the flooring plank. Generally multiple flutes or grooves. Just something to think about. Make sure you know what you're getting into before ordering things you might regret. I believe contributor J has the best recommendation if you want to run flooring on a 4 head.

You might want to ask what he uses for the first (bottom) head, as this is your finish cut to the face of the plank. I remember having issues with chip out using straight knives and lines with insert spiral.