spiral head jointer

[Todd S]

a few spiral head jointers are on the market. They are a few hundred $$ more than the conventional jointers. I'm wondering if they are worth the cost versus a 3 or 4 blade cutter head. thanks

[Guess who]

First I'll express my ignorance and say I didn't know they were available. But then, I'm wondering at any advantage, and think that if they don't have increased cutter head speed there is none that I can see.

A spiral blade, if a single blade, still contacts at only one point per revolution, while a 3-blader contacts 3 times per revolution in the same area of wood, if you get my drift. As the wood moves forward, the spiral turns, and effectively planes a strip at an angle to the movement, a bit longer strip, but still a single strip per single revolution of the cutter head. So, what's the advantage? It depends on the ratio of forward speed to cutter head speed. You might have only one blade to sharpen ...but how would you do that easily yourself? Being a spiral, it might have one advantage in that it is contacting the wood in a small area, not across the entire blade at the same moment, so this might cut down on stress and fatigue of the jointer, if that's a factor. I'm game to hear more possible advantages though to warrant the cost. Any options on a three-blade spiral cutter? Reminds me of the old lawnmower.

[mel]

a true spiral design has more of a shearing action to the wood fibers as opposed to a chopping action for one. Although not a true spiral knife design, since each individual knife edge is still contacting the wood at the same angle as a straight knife would, one of the advantages to a spiral cutterhead like Grizzly offers is the individual knifes can be moved around when they become knicked thus offering a little bit more life to the setup.

[Mark Jerde]

The reason there are drool stains on the spiral head jointers pages of my Grizzly catalog is they appear to be easier to align. Screw them in and you're done, according to the copy.

I like woodworking but for some reason I *hate* aligning knives, shimming tabletops, busting knuckles on trunions, etc. I have just a few hours a week in the shop (work is 37 miles away around the Washington DC beltway with its noteworthy traffic) and I'd MUCH rather spend time making sawdust than adjusting tools.

The spiral head's alleged ease of setup if the key reason its of interest to me. The alleged better finish is secondary.

-- Mark

[Bob]

Spiral head jointers have multiple blades.

I believe a spiral head cutter equates roughly to the same thing you see in hand planing by turning the plane at an angle to the planing direction. It cuts smoother with reduced tearout and handles difficult grain better.

Bob

[mel]

some actually have a true spiral blade as opposed to several straight blades in a spiral pattern

[DJ Delorie]

I have one. Yes, they're worth it.

[Andy Dingley]

A spiral cutter produces a constant force between wood and head as it rotates. A straight three blade pulses this force, three times per revolution. This may be enough to give a better finish.

I know I would spend $100+ to get a better surface finish from my jointer. I'd want to see it in action first though.

[Bob]

"flexible bladeS allow quick and easy blade change".

"number of knives (helical) 3 "

Bob

[mp]

If you're talking the Grizzly style spiral cutters, I can see a few advantages.

- if you get a nick in one of the cutters, you can rotate just the one cutter in a minute or so.

- shearing action gives better quality of cut, especially with difficult grain

- carbide cutters are much harder than steel blades, which means you won't need to sharpen nearly as often

[Steve Knight]

now this is a real spiral cuter head. the knives cut at a angle and they cut at a lower angle too.

[mel]

I meant this

opposed to this

[George]

Remember the Uniplane? Incredible machine. Still have one at the school, because they won't sell it. Even offered a hold-harmless agreement, but no dice.

[Seeker]

I feel like the best benefit to a spiral head cutter along with its smoother cut is the fact that there is no blade height adjustments or special setting gauges etc to fool with, just replace a tooth/teeth and go. Every planer/jointer should be like this unless you are one of those types who love to fiddle around with gauges and stuff just to says I was able to get it within a gnats ass of perfect adjustment.

[Bob]

blades, not one.

Bob

[mel]

so what's your point?

[Bob]

I thought your post was saying the Oliver had a single spiral blade. Maybe I misinterpreted. sorry about that. Somehow I read into the thread that some people were saying that a spiral head jointer has one single blade. Every spec I've seen says they have multiple blades but they are helical, not straight.

Bob

[Jim Weisgram]

There is another consideration. The "spiral" indexable inserts on Grizzly jointers, and I assume on others, are carbide. I suspect they are going to last a while.

[max]

Yes, but carbide is never as sharp as HSS or Carbon steel. I suspect that the cut will not be as good with carbide. Carbide is also more brittle that steel and could chip if it hit a pebble or nail. max

[Bruce]

On Sat, 13 Nov 2004 10:49:01 -0700, Jim Weisgram wrote (in article ):

I'd love it if some manufacturer made a jointer/planer that could use the inserts designed for metal lathes. You can get them in a bazillion styles and materials.

-Bruce