Maximum length of board on a 6" jointer

[lcm1947]

I know or at least pretty sure that this has been asked before but I couldn't find an answer thur the search above. What is the maximum length of board could you joint on the jointer? I appreciate it and if not too much trouble what length on a 8" jointer not that I'd get that big of one but am curious. Thanks

[LYU370]

Probably depends on how long your infeed & outfeed tables are. I've got a small 6" benchtop Craftsman jointer, anything past about 3' maybe 3 1/2' starts to feel somewhat wobbly and hard to control.

[LarryG]

Rule of thumb is about 2.5 to three times the length of the jointer's beds, depending on how good your technique is.

[vaking]

Larry,
Let me complicate the problem a bit:
I have a tradesman jointer, the one that was on sale at Lowes some time ago. It has native 16" infeed side and 16" outfeed side beds. Based on your rule of thumb - I can joint up to 4' on it. I know - too short for most people. Additionally, Jointer comes with one extension wing. Extension wing consists of couple of rollers mounted on 2 pipes and pipes get secured in cast iron beds. It can be attached to either infeed side or outfeed side and effectively doubles the length of the bed on the side it is attached too. I repeat - it comes with one extension wing which fits either side. Which side should it be attached? Does it have more benefit to attach it to infeed or outfeed or neither?
Presuming it is possible to find one more extension wing - does it make sense to get it and extend both?
The infeed side moves up and down when you adjust the cut. Outfeed bed is stationary. Does it make sense to mount the supplied extension to infeed bed and make your own stationary extension for outfeed? It will make jointer no longer a benchtop as it will need a stationary place but I can live with that?

[LarryG]

Good question, Alex, but tell me ... is the jointer on a conveyor belt?

(Bad joke, sorry. )

Ideally I think you'd want extensions on both tables but, if forced to choose, I guess I'd put it on the outfeed side. My reasoning is that at least in theory, on any given pass the board is more true as it is sliding over the outfeed table than it was when it was sliding over the infeed side. If the board is really wavy, in some respects a longer infeed table serves no purpose at all, especially on the first couple of passes. But things start evening out on subsequent passes, as the board becomes more true, which is why I say that ideally you'd want as much length on both sides as you can get.

[lcm1947]

So since the 6.5" Ridgid has a 45" bed then 3 times half that is 67.5" board it'll joint. Hmmm, that doesn't seem like much. I can see why the little bench top jointers would be limited.

[TheRic]

Rule of thumb is about 2.5 to three times the length of the jointer's beds, depending on how good your technique is.

So since the 6.5" Ridgid has a 45" bed then 3 times half that is 67.5" board it'll joint. Hmmm, that doesn't seem like much. I can see why the little bench top jointers would be limited.

I don't know, but it sounds like 2.5 to 3 times the total length, not the length on just one side. I could be wrong, I don't own one ( YET!!! ),so I have no clue. But would like to know.

[LarryG]

So since the 6.5" Ridgid has a 45" bed then 3 times half that is 67.5" board it'll joint.

No, TheRic interpreted what I wrote correctly (which I thought was unambiguous, but apparently not, sorry about that). The ROT is a range of 2.5 to 3.0 times the total length of the jointer's tables. In the case of the 45" long Ridgid (what I happen to own), the range would be 112.5" to 135".

One might legitimately ask, "Why a range? Why not just state the maximum?" It's similar to the nonsensical experience requirement you all-too-often see in Help Wanted ads: "Minimum 3 to 5 years experience." Okay, what's the minimum experience requirement? Three years? Or five years?

In the case of jointers, I have always assumed the idea of the range is that with good, sound technique you can routinely joint a board that's 2.5 times as long as the jointer's tables. With exemplary technique and an extra smidgen of care, you might push that to 3.0 times as long. Anything beyond that, you'll be unlikely to get satisfactory results.

In my shop, the limiting factor is the infeed and outfeed area. I can joint boards about eight feet long without running into a wall on one end or the other, so I have not been able to personally test the validity of this ROT.

[crokett]

No answers to add but another question - if you were anal about leveling them, why not make and add infeed/outfeed table extensions to your jointer? then you could joint boards a long as you needed.

[lcm1947]

Ho wait a minute LarryG, so you are saying that a 6" jointer will joint like up to 11' of board? That's a lot. Well then maybe one of those little bench top jointers would suit me just fine. I can't imagine me ever needing more then 72" and that would be for a table which I have no desire to ever do. More like coffee table, etc stuff. That's a good question Crokett and one I've been wondering about for some time but you never hear anybody talking about it. I guess it would be too difficult to get it that level or square, etc.

[LarryG]

Ho wait a minute LarryG, so you are saying that a 6" jointer will joint like up to 11' of board? That's a lot.

Yes it is; but don't forget, we're talking "rules of thumb" here and you know how meaningful those sometimes are. Some sources say only twice the length of the jointer. I've done 8' boards on my Ridgid without problems (2.13x its length) and if space permitted, I think I could easily manage the additional 16" that would take the multiplier up to 2.5x the length of the tables. It would depend on the width and weight of the board, though, as well as whether I was edge- or face-jointing. Truing up the edge of a lightweight piece of 1x6 pine from the BORG ... that's easy. Flattening the face of a heavy 8/4 slab of rough-sawn oak ... eh.

I probably should have been more emphatic about saying that going much beyond 2.5x would be really pushing it, something to be done only rarely, not regularly, and probably not with heavy, hard-to-manage workpieces. Again, spatial limits in my shop preclude my putting this to the test myself, but FWIW I've read that it can be done, if your technique is solid.

[SARGE..g-47]

Morning ICM...

I do a lot of face jointing working as I often get stock that comes directly from the mill and buy S1 and S2 commonly. My personal approach is to look at the project I am working with and note the longest lenght I will use. If it is 60" for instance, I will precut the 10' - 14' mill stock (common mill and yard lenghts) to around 66" to accomodate that lenght. Any other common lenghts in the project will get an additional 4" tacked on and cut enough for those, etc.

The point is I have a Sunhill 6" with a 56" lenght bed. Regardless of bed lenght the shortest lenght you can go with is the most accurate, safest and less wasteful over-all. My rule of thumb is that if the stock I have to joint over-laps either the infeed or outfeed tacle by more than 24", I will set up my Ridgid accurately to support it.

I have done as much as 96" lenghts on the jointer but only in situations that are absolutely necessary. My BT3000 has ripped stock up to 16' long. But... only after it became necessity and only after precise measures were taken to be absolutely sure that the stock was solidly supported fore and aft to eliminate as much of that potentialy dangerous situation as humanly possible.

Regards...

[lcm1947]

Thanks again LarryG for the reply. Yeah, I normally do take estimates and figures with a gain of salt so understand what you are trying to get across to me. I just appreciate your efforts and realize there's a lot of varibles involved and nothing is in stone but this kind of talk is helpful to me in order for me to make a decision. I appreciate your time.

[LarryG]

You're very welcome, but as a final thought I'll mention that Sarge provided some good input, too, and I work pretty much the same way he does, reducing the material to approximate lengths as the first step so that I'm generally working with the shortest pieces possible. This may seem wasteful, and taken at face value I guess it is; but to me the easier material handling is well worth the raw cost of the wood that gets thrown away, especially if there's an enhancement to personal safety.

[vaking]

Wait a minute.
Larry's rule says that my lame jointer with combined bed length of 32" can joint 7'. Never done that and it sounds scary. Imagine me trying to joint 7' board of 8/4 oak. At the beginning or an end of a cut I will have 16" on a bed and almost 6' hanging on a console. I am supposed to push down and into the knife that thing using a pushblock working with a leverage that has 16" working for me and 68" against. My math/physics tell me that I have to be pushing down with a force of somewhere around twice the total weight of a board using left hand only (I am righty). And not only be pushing down but also be ready to feed steady and be swapping hands without slow down. My rough estimate tells me that 2"X6"x84" of oak is about 50 lb and I need to apply twice that with each hand. Definitely not a walk in the park.

PS. For those that plan to built their own bed extensions- remember that outfeed bed is stationary but infeed is mobile. It goes up and down when you adjust the depth of a cut. There might be a chance to make your own outfeed extension but not an infeed.