Installation & Impressions of a Byrd Head

[Dan Larson]

Well, it’s finally done-- the Shelix head is in my Rojek J/P combination machine!

First of all, I’d like to thank the folks at Byrd, TechMark (Rojek USA</ST1:p), and a few helpful Creekers for their technical assistance. I had no previous experience doing this sort of thing, and everyone’s input helped make the project go pretty smoothly.

My main motivation to upgrade from the standard 4-knife cutterhead that came with the machine was convenience. I'm a hobbyist with very limited shop time. When I'm in the shop I want to working with wood. I don't want to be fiddling around with J/P knives any more than I have to. Lately I've been working with tropical hardwoods, so the knives have required more frequent attention than I'm willing to provide.

So why Byrd over Tersa? The Tersa would have been less hassle for me since the head is an off the shelf item from Rojek. I was at first leaning in this direction and was kicking myself for not ordering the optional Tersa when I bought the machine. A call to the Rojek sales rep changed my mind. He told me that the Byrd head was cheaper than upgrading to the Tersa at this point and also gave a much better cut. It's worth pointing out that the cut quality issue of the Tersa is specific to my machine. The inferior cut with this head is the result of the machine's relatively high planer feed rate in combination with the Tersa head for my machine only being a 3 knife set-up. Well anyway, it was a no-brainer choice based on this information alone. It's nice that the Byrd was supposed to be quieter and less prone to tear-out, but these potential advantages just seemed to be icing on the cake for me. Since Byrd head upgrades have been discussed frequently in this forum, I did question if I had let myself get sucked into a bit of hype...

After several months of putting the decision off, I finally did cave in and order the head from Byrd. I was surprised to learn that they had one for my machine sitting on the shelf. As it turns out they made it for another Rojek owner. When he installed it in his machine, he found that it left scallop marks on the stock. Bryd took back the head and made a new one for him, which apparently worked perfectly. Upon later inspection, the folks at Byrd discovered that the first head was manufactured correctly. The scalloping was due to a number of improperly ground carbide inserts. So after swapping out the inserts and pressing on some new bearings, Bryd sent the head to me. They shipped it in a sturdy crate, and it arrived unscathed.
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Swapping out the head was easier than I expected. I removed the old head by removing a few brackets from the machine, removing the drive belts, and then unscrewing 4 bolts on each bearing body and lifting out the head.
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I had trouble removing the pulley from the spindle with a bearing puller. Even torquing hard on the bearing puller, to the point that I was worried it would fly apart, and the pulley wouldn’t budge. Since I couldn’t remove the pulley, I couldn’t remove one of the snap rings. Instead of messing around with this anymore and risk hurting myself, I just ordered a new set of snap rings and pulley. With the new parts, I was able to get the Byrd head ready to drop in the machine. (Just for the heck of it, I tried removing the newly installed pulley. Slid right off the spindle with only minimal torque on the puller. I still don’t understand why I couldn’t remove the pulley from the old head!!!)
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Continued...

[Dan Larson]

Installing the new head back into the machine was a piece of cake. Just the 8 bolts, the accessory brackets, and the drive belts to attend to.
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Ok, so how well does it work?

First off, it’s uncanny how quiet it runs with the Byrd head—even while it is chewing on a board. Honestly, it doesn’t make any more noise than my cyclone! I didn’t expect to value the quieter operation much, since I always wear ear protection when I use the machine. But since it’s a more peaceful experience, I enjoy using the machine more than I ever did before.

So does it give a better cut than the old head? Definitely, without a doubt. But, it’s worth noting that I still have to pay attention to grain direction to get the best cut, and I still get minor tear-out on some boards. For example, I tried jointing the same maple board with the old & new cutterheads. In both cases, I paid attention to the grain direction and took very light cuts. With the old 4-knife cutterhead I experienced quite a bit of tear-out. (Sorry… I didn’t think to get a picture at that point.) In the pictures below, the same board is shown after jointing with the Byrd head. Very little tear-out, mainly in an area of shifting grain direction.
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There is one small issue with the cut. I see one light scallop mark on the stock. I suspect that Byrd may have missed one of the defective inserts and failed to replace it. At some point I'll have to try to locate the offending insert and replace it.

I haven’t had a chance to use the machine very much with the new head, so I can’t comment on the durability of the carbide inserts. But I think it’s safe to assume that they will not need to be rotated nearly as often as the HSS knives needed to be sharpened.

A few final thoughts. The Byrd head does offer some genuinely tangible advantages over a conventional straight knife cutterhead. It does run much quieter, offers a more durable cutting edge, and the shearing cut can be helpful when working with tear-out prone woods. Based on my experience, though, don’t expect to feed stock without regard to grain direction and you probably will still occasionally see at least some tear-out. Now the biggest question—in this case the Bryd head was $1200—are these advantages worth that kind of cash? I’m satisfied with it... but I guess it's up to you to decide for yourself.

Dan