Thread: 6" Jointer -UPGRADES?

You will find some helpful info from this thread on the forums titled "Improving machine cabinet dust ports"

For jointer cabinets in particular, check out the chain starting at post #50 by bueller. I think this comprehensively covers what you're talking about.

I have an older JET 6" jointer and will be looking to do (at least some of) the modifications in the above thread sometime in the future (after I tackle the thicknesser), so can't give any personal experience in the improvements.

I have read somewhere on the forums that openings around 1cm or less in any dimension should be taken as half their total area, as the smaller dimension dominates in air flow restriction. So there is a good chance that the space between the blades and louvres contribute even less than expected.

6" ducting and opening up the machine ports are just as important as having a powerful enough extractor so good job in tackling this!

“Without substantially modifying the cabinet, I can't see any logical way that I'll notice any improvement by just fitting a larger outlet connection.”

And you’d be 100% correct.
Ive used many jointers and planers over 40 odd years, mine now has hundreds of metres across it some weeks. Every one has only ever been connected with 4” hose, to a good, clean, powerful extractor, and I can not remember one incident where it has blocked up.
Save your time and energy and use it elsewhere, to make stuff. This “ you must have 6” outlets” is a load of codswallop.

Originally Posted by riverbuilder

Ive used many jointers and planers over 40 odd years, mine now has hundreds of metres across it some weeks. Every one has only ever been connected with 4” hose, to a good, clean, powerful extractor, and I can not remember one incident where it has blocked up.

Save your time and energy and use it elsewhere, to make stuff.

You can probably tell from my post that I'm almost convinced! Particularly given the amount of use my gear gets - although I have to say that the dust collection bits and the mods to the cabinet are "making stuff"!!

Originally Posted by LickinChips

You will find some helpful info from this thread on the forums titled "Improving machine cabinet dust ports"

Thanks! That's exactly the thread I was "fishing" for - I knew it was out there somewhere! It was @BobL's illustration at #54 I'd remembered but couldn't find.

For jointer cabinets in particular, check out the chain starting at post #50 by bueller. I think this comprehensively covers what you're talking about.

I have an older JET 6" jointer and will be looking to do (at least some of) the modifications in the above thread sometime in the future (after I tackle the thicknesser), so can't give any personal experience in the improvements.

The problem is that any mods imply substantial metalwork - and that's not my go! But we'll see.

The thicknesser is in a similar boat - it's an el-cheapo 12" which for 30 years has adequately carried all the chips away (and I'll happily admit that despite it appearing to do a sterling job, there's no doubt some dust in the air - but not so much that limited use and a good respirator won't fix, followed by a wipe down every now and then with a damp cloth!) - I can't find any similar threads for the generic thicknesser, if you can point me to a post I'd appreciate it.

I have read somewhere on the forums that openings around 1cm or less in any dimension should be taken as half their total area, as the smaller dimension dominates in air flow restriction. So there is a good chance that the space between the blades and louvres contribute even less than expected.

All of which is true in theory, but without wanting to dissuade anyone from the one true path, that's all the inlet that exists at the moment and it does a reasonable job despite that theory. Of course that may well be because air flow at the machine is not so flash . Again bear in mind the total use the machine gets, and that at some point (now for me) improving dust collection becomes one's hobby rather than making stuff!

6" ducting and opening up the machine ports are just as important as having a powerful enough extractor so good job in tackling this!

The six inch ducts have been in place for almost 20 years, the extractor (and many will shudder) was once recommended by Bill Pentz (but that was in the last millenium) and is now considered by all to be insufficient. Yep it could be improved. No, it's not going to be, because it's "good enough" for what I do and there's a point where one begins to chase one's tale.

I'll repeat for the benefit of anyone stumbling on to this thread - I have significant allergy to wood dust, so am not being flippant. I have extractor, exhaust fans, filter and always wear a respirator (not a paper mask). Woodwork is also one of many hobbies, I'd rather be using a boat than building it, no matter how much pleasure the latter gives, so my exposure to hazard is limited because most of my time does not involve cutting sanding or planing stuff.

According to this table from the Bill Pentz website, a 6" jointer only requires 350 CFM for chip collection, and 436 CFM to meet Medical Euro (fine/invisible dust) collection
Machinerydustflowrequirements.jpg
Chip collection requirements can usually be achieved using 4" ducting which has a typical max of 425CFM with a powerful enough DC. Of course when a 4" duct is attached to stock planers it does not deliver the same flow. Unfortunately that 425 CFM assumes zero air obstruction at the machine end of the ducting which is rarely the case.

I have tested the airflow through several small stock planers with 4" outlets and measured between about 320 (eg 19mm edge planing) and 250 CFM when planing full width boards but even these lower flows were usually enough to obtain sufficient chip collection to prevent chip blockages because when the full width boards are removed this allows more air into the dust stream.

While this flow is OK for chips it will not in the long term be sufficient for fine dust but replacing the 4" with 6" ducting/port on a planer will do very little unless the air flow path is improved. Bueller's thread details a typical solution to this.

For those that don't wish to modify their small planer some forced ventilation will easily take care of escaped fine dust generated on these machines.

When I visit mens sheds I usually recommend not attempting to modify the ports on every single machine n their shed but to establish a priority with the dustiest machines attended to first.

The last machines that need attention are small jointers and drill presses.

Drill presses can easily get away with 4" ducting and a bell mouth hood because that duct is NOT attached to a machine/port hence is "naked" and has not machine restriction.

The other thing to remember is that fine dust production depends strongly on the type of action involved and the sharpness of cutting blades. Abrasive action such as used by sanders will generate more fine dust than cutting actions like planing and blunt blades make more fine dust than sharper ones.

Many thanks for that response @BobL.

I have been through this many times in the past - which is why these machines are at the very end of the process! I am glad that the science bares out my observations more or less, so the heresy charges can be left on the back burner for a bit!

I will make a slight improvement to the "air in" I think, but will happily upgrade to a true 4" (100) connection (as opposed to the 90mm net that it has stock) and with a mostly rigid connection should get the flex down to less than 70cms (because that sounds so much less than 700mm!)

That spreadsheet also answers my thicknesser and drum sander questions - although I may well muck around with both in the course of the coming months, just for fun.

The bonus is that the 4" connection is much more in keeping with the scale of the machine, so it will be a lot less cumbersome to deal with.

Thanks again - I hope that having a specific thread for this will make a search result easier to lead others to it in the future.

Here's the plan for the connection upgrade I looked at more of a bellmouth but without cutting metal the geometry is problematic, it still needs a tweak but it's better than the plastic plate with the round hole that we have at the moment. I'll post the finished article here (in a few weeks or months!) to complete the thread.:

21-01- 12 at 13-17-22.jpg

Cheers,

P

Well it's a few weeks and here's what the finished product looks like. Actually it looks like the drawing which is not surprising I suppose!

21-01- 25 at 19-14-48.jpg

The thickening about two inches out from the machine is a split-line because due to printer size limitations I couldn't print it in one piece.

Was it worth doing? Well yes - it looks like a bought one, and cost ten dollars in plastic and ahem... 36hours in print time. I could have printed much quicker but I'm going through a phase where I like the smooth look.

Will it improve things? Probably not. (see the conversation above) However with 25% more area, and a much cleaner transition to the ductwork (700 of 100mm, 700 of flex, then 150 all the way) it won't be worse, and I'll be happy, which is the whole object of making stuff anyway.

Waiting now for the magnets to arrive and I'll finish off the new connectors - I don't need them either, but there you go.

Cheers,

P

Yep, looks the goods. These printers are a great thing, I have a 16 year old kid who hangs around my workshop a bit, I think I’ll commission him to make me an undertable one for the spindle moulder.