In a discussion about a spiral cutterhead and helical cutterheads, it’s important to first discuss whether the woodworking shop tool inventory should include a planer and a jointer.
Although we wrote about the must-have tools for a beginner woodworker’s shop, we did not include either in what ended up being a very long list. Were we to write that article again, we might very well include both to the list.
Jointers will flatten one face on a piece of wood and square up one corner of it; planers then will make the second face flat and parallel to the first face. These features do come in pretty handy on woodworking projects.
A planer can be found for under $100, a small unit if you are a smart sharper, but a decent benchtop planer will run you around $350.
A jointer will set you back in the low to mid $200s if you shop right.
If you are wondering what the difference is between a jointer and a planer, read this article.
The cutter heads for the jointer present a choice for you beyond the make, model, and price of the jointer. They do exactly what the name implies: they cut the piece of wood as it is run through the jointer and presented against the cutter head. There are several styles of cutter heads to choose from, with spiral being the new kid, while straight knives and helical cutter heads are the older kids.
Straight Blade Jointer Cutters
Straight knives are inexpensive and will make smooth cuts for you. However, they will lose their sharpness quicker than carbide knives on your jointer.
They will also create larger shavings as they do their cutting and fill your shop vac faster as a result. They do require some maintenance, and replacing and aligning replacements can take some time. It’s not simply swapping out an old one for a new one.
You’ll find straight knives on less expensive and older jointer models. While straight knives will cost you less on a straight purchase (no pun intended), they’ll actually end up costing more because you’ll replace them more often than you would a spiral cutter head (more on that in a moment).
Spiral Cutter Head For Jointers/Planers
Spiral cutter heads are the newer cutters available for jointers. Their inserts (the cutting edges) are carbide and will hold their sharp longer than straight blades, meaning they do not need to be replaced as often as a straight knife. The inserts are also easy to replace and require little maintenance.
They create smaller shavings for the dust collection system to gather up and remove from the work area. All you have to do with a spiral cutter head is rotate the bit to bring a new edge into play when an older edge has lost its sharpness.
The blades of spiral cutter heads encircle the shaft. The blades are positioned straight around the shaft, which distinguishes them from the helical cutter head (more on that in a moment. Spiral cutter head action and performance is akin to a hand plane.
Their primary application in the woodworking shop is to make cuts on soft, low-density woods. They are durable and have a long use life, and are able to handle more wear and tear than can a helical cutter head.
Helical Cutter Head for Jointers/Planers
Helical cutter heads are not that dissimilar to spiral cutter heads and vary mainly in a couple of ways:
- First, they differ in the alignment of the cutters to the axis and the number of blade inserts.
- Secondly, the cut edge will be 14 degrees off the axis of the cutter, while the cut edge of the spiral cutter head is perpendicular to the jointer feed rather than angled like the helical cutter head.
While those are the main differences, their function differs, too. While spiral cutter heads cannot make deep holes, helical cutter heads can. Spiral cutter head blades are driven in an inward motion against the wood being cut, and the result is a clean cut with no tear-outs.
Helical cutter heads will tend to be more accurate than spiral cutter heads and are better suited for fine detail work. They are better suited for harder, denser woods than a spiral cutter head and when a cleaner finish is needed.
Differences Between Spiral and Helical Cutter Heads
While both spiral cutter heads and helical cutter heads work well and remove unwanted material from the piece of wood, there are some differences to consider.
- Helical cutter heads are more expensive than spiral cutter heads., making spiral cutter heads the choice for a limited budget. In researching for this article, we found a helical cutter head for just under $2000, although that was on the extremely high side. The range for these cutter heads is between $325 – $475, with helical cutter heads being at the higher end of that range and spiral cutter heads at the lower end.
- Helical cutter heads are generally easier to clean because they have no leading edge like spiral cutter heads do. The blunt edge of the spiral cutter head allows for some removed material to build up while they are cutting, and it is important to clean them after each use to maintain their effectiveness.
- Helical cutter head blades are interlocked along the shaft, making them stronger than spiral cutter heads. There is always a cutter blade working against the piece of wood, too, as a result of the angled row of heads.
- While there is some disagreement among experienced woodworkers as to which of the two will produce a smoother cut, the difference is not so great that one stands out over the other.
Helical Cutter Head In Action
We came upon a very informative and helpful video from a woodworker who has used a helical cutter head on his planer for more than a year, an expensive upgrade, to be sure. But his comments, observations, and experience are worth noting.
While he speaks highly of his helical cutter head, and with a lot of experience in its use, there is the cost factor to consider, too. Some of us can’t swing the higher price of a helical cutter head. We found a number of bulletin board comments, also, about the difference in smoothness of cut not being so pronounced that it is determinative of the choice to be made.
Budget considerations and the tasks most likely to be needed in your woodworking shop will determine your choice whether to upgrade, as the videographer did, or stay within a lower budget and still get a smooth cut.
There are differences between the two, but do you really need the upgrade if your shop is small and the need is occasional? We see this as the defining question, and with a soft budget, the spiral cutter head will do us just fine.