Sedgwick MB planer dust extraction

[Doug71]

So I made a dust extraction hood for my Sedgwick MB, kind of copied the factory one but in wood and am a bit disappointed with the results. Some shavings go down the pipe but I am left with a bigger pile than I hoped on the floor whether planing or thicknessing.

I am using a Jet extractor and 4" hose which moves 1,100m3/hr which is more or less what Sedgwick recommend (1,105m3/hr) as a minimum although they do recommend 5" pipe. I could run the Jet with 6" hose giving 1,620m3/hr but this means spending probably £100+ on hose and it might not solve it? Anybody recommend a good place to buy hose from?

I see the proper Sedgwick dust hood has holes in the back, I didn't put these in mine as in my mind it's better sealed but I guess they must know what they are doing so I will try putting some holes in mine, maybe it helps pull air in the right direction?

Any advice or experience appreciated.

Thanks in advance, Doug

 

[Cabinetman]

My planer thicknesser runs on 4 inch with no problem. But there is a three phase beast pulling it!
I have come to the conclusion that dust extraction is a little bit counterintuitive, I tried fitting a reducer down from 4 inch to about an inch and a half for general tidying up around the workshop and it lost all its suck, I imagined that reducing it like that would increase the vacuum effect. So yes, I think drill the holes as it’s possible the area of the vent in the hood you have built isn’t large enough without them. Ian

 

[Mike Jordan]

You may have seen my version before. Air enters under the edge you can see and at the ends to some extent as well as past the cutter block Ihave a 1.5 HP extractor and have never had any problems. I think it could be made in timber.

 

[doctor Bob]

try just lifting the box 5mm off the bed, as a trial just use a few screws in the corner.

 

[Inspector]

Doug there are several reasons you aren't getting the performance you want.
DC's usually move half the claimed air flow.
4" pipe can flow a maximum of 675 m3/hr. Usually less and even less with hose. That's why they recommended 5" duct. The 6" would be best if the DC can actually pull that much air.
There needs to be air flowing into the space you are drawing from. If air can't flow through the sawdust and shavings can't be picked up. Pinch your nose closed. No matter how hard you try you can't get air into your lungs. Same principle and the reason the factory hood has extra holes in it.

Pete

 

[sploo]

My planer thicknesser runs on 4 inch with no problem. But there is a three phase beast pulling it!
I have come to the conclusion that dust extraction is a little bit counterintuitive, I tried fitting a reducer down from 4 inch to about an inch and a half for general tidying up around the workshop and it lost all its suck, I imagined that reducing it like that would increase the vacuum effect. So yes, I think drill the holes as it’s possible the area of the vent in the hood you have built isn’t large enough without them. Ian

At low pressures, air kinda acts like water (in that it doesn't compress well). Hence restricting the size of tubing or ports on a HVLP extractor will kill the air flow. Vacuums (LVHP) don't suffer to the same extent.

 

[Cabinetman]

At low pressures, air kinda acts like water (in that it doesn't compress well). Hence restricting the size of tubing or ports on a HVLP extractor will kill the air flow. Vacuums (LVHP) don't suffer to the same extent.

Thanks that just about sums it up! I noticed your an extinguished member, as opposed to a distinguished?

 

[Doug71]

So after a bit of a design change or two (spent all day messing with it ) a few angle changes, a few holes drilled and making it a bit longer it is working better. I'm happy with it now when planing over the top but it still doesn't catch all the shavings when thicknessing, some get thrown back out of where you feed the wood in. Not sure if this can be improved or if it's just the nature of the beast.

Think I might look at upgrading to a 5" hose as I swap it between my planer and Wadkin spindle moulder so guess they will both benefit from it. Should I go for 6" or is that overkill? The extractor takes two 4" hoses or one 6" if you remove the adaptor.

 

[PAC1]

I have the JET 1100 with 175mm ducting and 125mm final connection it removes 99%of the shavings from my 410mm thicknesser, so I would get 6". It is also great on the spindle. Be careful not to stand too close or you may get extracted yourself!

 

[Doug71]

I have the JET 1100 with 175mm ducting and 125mm final connection it removes 99%of the shavings from my 410mm thicknesser, so I would get 6". It is also great on the spindle. Be careful not to stand too close or you may get extracted yourself!

My extractor is a Jet 1100, sure it takes a 150mm but will check tomorrow.

Just found this place and the hose etc is cheaper then I thought (originally looked at Axminster £££) so will probably go with the 150mm. Has anyone used them?

https://www.dustspares.co.uk/

 

[mikefab]

I never got decent extraction with my Sedgwick MB. I had a plywood chip collector I made which performed pretty much as Doug is describing, and then eventually bought a metal one from a Sedgwick and it really wasn’t any better. That was with a good size extractor and a 125mm hose.
There was always a sizeable pile of shavings to sweep up both when surfacing and thicknessing.

 

[mikefab]

Just found this place and the hose etc is cheaper then I thought (originally looked at Axminster £££) so will probably go with the 150mm. Has anyone used them?

https://www.dustspares.co.uk/

Yes I got all the galvanised ducting etc for my workshop from them and continue to use them for extractor bags etc

 

[Trevanion]

Did you do any tests planing without anything in place to see the path of the chips as they come off the block?

 

[Doug71]

Did you do any tests planing without anything in place to see the path of the chips as they come off the block?

No but I will tomorrow

The planer came with an original old fashioned dust chute that you don't fit an extractor to but instead just fires the shavings up in to the air, I will also try that on tomorrow and see if some chips are still thrown back......then sweep up the snow storm it causes, I don't know how people use these things without extractors.

 

[Inspector]

Should I go for 6" or is that overkill? The extractor takes two 4" hoses or one 6" if you remove the adaptor.

Go for 6" and chuck that adaptor. Having the two 4" pipes converging abruptly like that in front of the impeller creates turbulence where you don't want it.

Pete

 

[sploo]

Thanks that just about sums it up! I noticed your an extinguished member, as opposed to a distinguished?

It fits with my general decreptitude

 

[sploo]

Think I might look at upgrading to a 5" hose as I swap it between my planer and Wadkin spindle moulder so guess they will both benefit from it. Should I go for 6" or is that overkill? The extractor takes two 4" hoses or one 6" if you remove the adaptor.

Ignoring the "pi" (which cancels out), the area of two 4" hoses is 2x2^2=8. The area of one 6" hose is 3^2=9. I.e. a 6" is a closer match to two 4" hoses.

A 5" would only be 2.5^2=6 25.

 

[Rob H]

I made this for mine, I still use the box when planing tho. I have the Jet JCDC-1.5 Cyclone Extractor but only 100mm hose throughout the workshop but I have got some 6” waiting to be fitted at some point

 

[Doug71]

My 6" hose and fittings turned up today so I knocked up a quick new dust hood out of MDF this evening, it's a bit of an improvement but not much.

The biggest improvement has come from a suggestion from @Trevanion to look and see where the chips actually go (sounds obvious when you say it ). When surfacing a lot of the chips come back towards the operator and I have found extraction works best with the dust chute stuck in from the operators side, seems wrong to me but it works!

I can't seem to improve extraction when thicknessing, you can feel the air being blown back at you from the block when putting stock under the thicknesser and this air carries dust and chips with it. Don't get me wrong most of it goes up the pipe but more then I would like is blown back at me.

I guess it's just an old machine built before dust extraction was an issue, I might give Sedgwick a call though in case they have any tips that might help.