Straight knife versus carbide spiral insert head and stringy woods

[Anthony Whitesell]

aaaaaaaaaaa

[Steve Peterson]

I am in the process of setting up my shop after a move and don't have my dust collector set up yet. I occasionally need to flatten a board or two on my jointer with a Shelix spiral head. I keep the blast gate closed and scrape the sawdust out every couple of minutes. I get to see every bit of sawdust coming out of the jointer and there are no strings. It is more like small chips about 1/4" by 1/8" or smaller.

Steve

[Anthony Whitesell]

I am in the process of setting up my shop after a move and don't have my dust collector set up yet. I occasionally need to flatten a board or two on my jointer with a Shelix spiral head. I keep the blast gate closed and scrape the sawdust out every couple of minutes. I get to see every bit of sawdust coming out of the jointer and there are no strings. It is more like small chips about 1/4" by 1/8" or smaller.

Steve

What kind of wood? I think that is key. On my straightknife G0490, I have no problems with maple, walnut, or red oak. A little issue with poplar, and more of an issue with eastern white pine. It seems like the strings tingle into a clump. The hardwoods seems to chip and break apart on their own, where as the pine does not.

[Steve Peterson]

What kind of wood? I think that is key. On my straightknife G0490, I have no problems with maple, walnut, or red oak. A little issue with poplar, and more of an issue with eastern white pine. It seems like the strings tingle into a clump. The hardwoods seems to chip and break apart on their own, where as the pine does not.

Most of what I doing now is just construction grade lumber. Mostly douglas fir and the white SPF from the BORGs that could be spruce, pine, or fir. I am in California so I don't have access to eastern white pine. I don't see any strings in the sawdust.

I am having a difficult time understanding how any jointer would produce stringy chips. The head it moving significantly faster than the wood. Does it just bend back a sliver of wood until the next blade comes along?

The spiral head is supposed to be angled to shear the wood as each tooth passes. Most designs use a 4 sided insert with slightly curved sides that match the circular shape of the head when they are angled just right. There are a few cheaper designs that just use flat 4 sided cutters mounted squarely. This save a couple of inserts, but probably won't help much with stringy wood. Go for the angled design.

Steve

[Andrew Hughes]

I think he's talking about a shaving that is cut from across the width of the wood.I see them long in my dust collector can esp after a new set of knives that are set correctly in my Oliver.So I take it as a good sign.A poorly adjusted machine with dull knives will not produce this type of cut from popler or pine.

[Anthony Whitesell]

Most of what I doing now is just construction grade lumber. Mostly douglas fir and the white SPF from the BORGs that could be spruce, pine, or fir. I am in California so I don't have access to eastern white pine. I don't see any strings in the sawdust.

I am having a difficult time understanding how any jointer would produce stringy chips. The head it moving significantly faster than the wood. Does it just bend back a sliver of wood until the next blade comes along?



Yes pretty much. It's a lot like trying to peel an apple in one long strand. Sometimes it peels in little pieces, sometimes in long strips. This is also due to feeding into the cutterhead instead of with it. If you could reverse the cutterhead direction it would always produce chips as there is no previous material to hold on to to get long.



The spiral head is supposed to be angled to shear the wood as each tooth passes. Most designs use a 4 sided insert with slightly curved sides that match the circular shape of the head when they are angled just right. There are a few cheaper designs that just use flat 4 sided cutters mounted squarely. This save a couple of inserts, but probably won't help much with stringy wood. Go for the angled design.

Steve


I will keep this in mind. I'm hoping to get a planer I can refurbish and save enough money on that I can afford to swap out the head to a carbide insert head. I wish I had spent the extra money and gotten the G0490X in the first place.

[David Hawxhurst]

mine are angled like steve mentioned and i've not seen anything more than just small chips when planing. i've planed all sorts of woods including so pine just not sure what type of pine it was but in came off in chips just like the hardwoods. they do compact better in the chip barrel better than my previous straight blade planer.

[David Kumm]

Generally a spiral head will throw off chips that are easier for a collector to handle than the long strings from a straight blade. If the finish you are getting is good with the knives, I'd argue the money would be better spent upgrading the DC. If a collector is expected to save you from fine dust, it must be powerful enough to handle the shavings or chips of any type. Dave

[Dan Hahr]

I think the OP would have to feed the stock into the cutterhead at like a 100 miles per hour to get a chance at a long shaving. The longest you could get is the width of the knives, but that would be only if the wood didn't have any microscopic breaks running with the grain. With a spiral, you aren't going to get any longer than the width of an insert.

Dan

[Anthony Whitesell]

You're making me wish I had spent the money on the spiral head in the first place. :rolleyes:

[Scott DelPorte]

I often run eastern white pine through my planer with carbide spiral cutter head, and notice only chips similar to what Steve reported. Most seems to be about 1/8 of an inch or so long and about the same width. Based on how the head contacts the board, I cant see a way for it to produce long chips.

[Anthony Whitesell]

That's the type of confirmation I was hoping for.