need help designing dc shroud for dw718 chop saw

[Alan m]

hi all
this is my saw it is a dewalt 718.
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the dust extraction is useless (2% at best with ct 22 at full, not even a sign in the bag)
i want to make a shroud for behind the fence that will colect the dust. i will conect this to the ct22 with a 50 mm A/s hose.
i did a trial mock up with an old bottle. this seams ok but needs shaping to fit properly.

has anybody got any ideas. design, materials, ways to attach it,

i was hoping to make it a consertina arrangment or elastic to allow of angle changes.

i was thinking of using magswitchs to attach it to the saw

 

[Alan m]

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[Alan m]

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[Alan m]

bump.

 

[norwegian wood]

since you have gotten no responses i think most people might think you are joking with that cleaner bottle behind your blade.  most of your dust will spew over the top of it.

 

[bobbobbob]

How well does the collection work if you hook the dw718 dust chute to a ct?  I would start from there since most debris will come straight off the back to the blade.  I don't have one of these so I don't know what you're starting with...

 

[Alan m]

do people think im joking

you would be supprised . when the saw is down it cant go over it. in fact as this is only a mock up the dust goes under the bottle rather than over it. i have no intension of using the bottle , i only used it because the dc hose fitted . [attachthumb=#]

the dc to the 718 port is useless maybe 2% effiecient as it is too small and in the wrong place

 

[Alan m]

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too small and the material part gets sucked up blocking the small hole. the pipe in an eliptical shape and not worth making a funnel for

 

[jimmy7]

PMSL.Just buy a kapex [laughing]

 

[awdriven]

I have the dual-bevel non sliding version of your saw. It's decent value. I'm sure it doesn't hold a candle to the Kapex, but there was no Kapex when I bought it and now I'll just use this saw until it's toast.

Only about half of the sawdust goes into the bag / collection hose. Fastcap makes a 'hood' that goes around/under the saw and catches more coarse sawdust - may not be that helpful if you work with much MDF. MDF dust is so fine it just floats around in the air.

Your idea is interesting though - a bellmouth around the kerf area and a strong suction may be able to capture more of the dust. I thought your bottle idea was clever. Anything you add to the saw has a chance of being contacted by the blade. Lightweight plastic would be safer than any other material short of maybe cardboard, which wouldn't be very durable.

 

[bobbobbob]

Looks like from your picture the dust 'flap' is too small at the bottom - where it needs to pick up.  Have you tried enlarging that piece?  I did that for my Makita and it worked wonders.  You could use whatever is flexible and not brittle. Worth a try since it would only take a few minutes to do...

 

[Guy Ashley]

Alan

I have exactly the same problem as you with dust collection with my DW718. I have tried constructing MDF hoods which loosely attach to the DW mitre saw stand but they have to be HUGE to accomodate the sliding bars when you move the saw to 45 degree cuts and then the suction in the hood is insufficient.

Every time I use the damn thing I end up coughing like an asthmatic pit pony and walk away thinking of what can I rig up but have never found an idea that works yet.

I have seen the Fastcap hood but it requires more backspace and it doesnt look that effective to me.

I honestly think the problem is that stupid small extraction port and it is simply a design fault.

I can see where you are coming from with the bottle idea but if you are cutting through an 8" x 2 1/2 oak slab most of the dust will be flying over the catcher.

That is where the Kapex wins with the extraction port being next to the blade and not at a distance from the blade as it cuts.

If anything the Kapex is the solution and is on my "wish list". Just hope my lungs hold out long enough!!

 

[Alan m]

. i cant afford a kapex now or in the near future. i removed the stupid dc flappy think but there is very little suction from the pipe as it is too small. i was thinking of making it out of a stretchy material to allow for the angles but havent found one suitable.
as for the fast cap saw hood , i have one(first attempt at fixing this problem) but it is way too big and aqward. it would be ok outside or in a big room. the efficiency of this mock up seams worthy of a look further into it. .

 

[Alan m]

does anybody know of any refinment to the shape i should make. i am thinking of making the DC port come out more towards the back as it will be in the way of miter cuts on one side any way.