Quite a few of you, like myself, have questioned the viability of switching straight knife cutterheads on planers and joiners to some form of helical heads. I recently was backed into a corner with my Powermatic 225 which had a factory original Quiet Cutterhead on it. After spending six hours, breaking three allen wrenches, twisting out 10 to 12 screwheads, facing knives soaked in penetrating fluid that refused to move and only three of nine knife rows tackled, I gave up and started the search for a helical cutterhead. Byrd was the first choice as I'm no more immune to advertising than anyone else. However, Byrd had a three week lead time on the head for my machine, and I didn't have three weeks. Further searching brought up Hermance Machine Company out of Williamsport, PA. Long story short, Hermance was able to get me a cutterhead in two weeks.
I don't have a Byrd nor have I ever been around a Byrd to compare the two head styles so I'm not able to say much about the difference between the two head styles. Byrd uses exposed teeth placement where Hermance protects the three sides of the tooth not in use. Byrd has a spiral layout where Hermance uses a V pattern.
I finished installing the new Hermance head yesterday. I turned the machine on and literally, the motor is louder than the head, not just idling but while planing oak! I couldn't believe it and still can't. Our dust system is the largest source of noise while planing and with it and the planer running while planing oak or maple, you can talk in normal tones standing right beside the machine. This is on an older heavy 25" planer that normally is so loud you can hear it a block away. So claims on noise reduction are 100% real.
While researching helical cutterheads, I ran across many potential purchasers worried about ridges or grooves being left in the board from the planing process. We've run several hundred feet of oak through now and the marks left look just like the planer marks from my 15" Powermatic with straight knives. The helical head leaves nothing worse. Yes, it needs sanding but I hope anyone that calls themselves a quality cabinet or furniture maker is sanding behind a planer anyhow. Hermance helical cutterhead planer marks are no harder to remove than regular straight knives.
In fact, sanding is taking a little less time because there is no tear out on the wood with the helical cutterhead. It doesn't matter which direction you run grainy wood, it doesn't tear out like a straight knife tears wood.
Changing teeth isn't a big problem. It took me about 1 1/2 hours to install all the teeth a job that any monkey could do. Hermance sends a torque wrech and T25 bit for installing the teeth so no additional tools are needed. Hermance does have 54 fewer teeth than Byrd for my machine so that saves time and money changing teeth.
So while I can't say Hermance is better than Byrd or the other way around, I can say without a doubt, the money I spent on the new cutterhead was worth every penny. I strongly recommend looking at Hermance if you're thinking of a helical cutterhead for planer or joiner. They are a little higher priced but I like the head design better and the fact I'm using less teeth per change.
I hope this helps some of you that are in similar situations as myself two weeks ago. Info is a little difficult to find and there's too much negative trepidation regarding helical cutterheads.
(Solid Wood Machining Forum)
From contributor B:
We have an SCMI planer with a Byrd head and we get similar results. I would never buy a straight knife machine again.