1-1/4" Intake + 1-1/4 Exhaust + 5-Gallon bucket

[Jonnynadeau]

I currently have a Shop-Vac 2-hp 5 gallon but like most of you, mine plugs in minutes. Since I already have 28' of 1-1/4" Shop-Vac Hose. I was wondering if this "design" would be ok to use with 1-1/4" hose.

Here's my considerations:

1: I don't have a planer so I really don't have to worry about the wood stringies clogging up my setup.
2: My biggest chips/chunks I'm making is from a router in which I religiously use MDF. Then the occasional shop floor vacuum.
3: I'm not worried about air born materials I do 75% of my work outside. I just want more separation of the materials BEFORE the filter.
4: I'm thinking of using 1/4" MDF for the baffle and building the "housing" out of 3/4" MDF. The baffle opening about 1" since I'm working with 95% finer chips. If some of the bigger things go to the vacuum, oh well, I just want more fines than chips.
5: intake size: I'm going from round to square, how should I go about this, is there an equivalent size opening to minimize turbulence and "inject" the air cleanly? I was thinking the measurement from the top of the baffle to the bottom of the top piece (or cover) should be 3" (4 pieces of 3/4" MDF stacked/glued) but if my math is correct my tangential injection opening is merely 3/4" x 3". Does this sound correct?
6: my exhaust should poke half way into the 3" chamber.

Does anyone think this will work? Yes, no, why?

I'll be designing/tweaking this until it warms up outside so no real rush. ND winters may last until mid-May, so seriously, no rush!

[phil (admin)]

Separators don't have to be round, but if they aren't round, they have to be much larger for the debris to have a chance to fall out.

So you are talking about making a rectangular separator, where the debris doesn't spin?

[Jonnynadeau]

Yeah it'll be round. I'm going to use about four moon shaped cut outs to make a circle shape. Then stack these moon shapes four high (creating 3") glued to the 1/4" mdf baffle. The moon shapes will create a circular shape. I'm using the moon shapes to reduce waste although they can be circle too for ease of the build.

[alan m]

i tried my fist seperater with segments.
it dint work great. the joints leaked a bit
i should have used a PU glue that would foam up.

i scraped that one and made another out of solid disks. it wastes more material but it is handier.
when i did my 6"one i made the first layer with a router and tramel , then jigsawed out the rest leaving a bit extra
then i glued and screwed each layer on top of the last. each time i used a bearing guided flush bit to folow the shape
it worked great

[Jonnynadeau]

Great idea, i never thought about making a 'template' with the first layer. Well, Alan, you killed my segment idea! how would i go about making/designing an intake port tangent to the outer ring. obviously it'll be 3" tall but how wide should it be.

My Shop-Vac has 128CFM and 54" of pressure. this is what it says on the website.

Im still curious if my 1-1/4" intake/exhaust idea is worth a shot? I'd rather not upsize the hose if i dont have to. I could go up to a 2-1/2", but since i have an 8' hose and a 20' in 1-1/4" I'd rather use the ones I have.

[alan m]

when i built mine i used a a 6"round to rectangular transition so i just left a piece out the width of the transition.
if the hose is 1.25" i wouls leave a corner on the blank (if you started with a square and put a circle inside it then leave one corner on the outside )
then you willll have a 90 degree flat to drill into. then remove (or dont if you want) the corner.

i made my 4" seperater a top inlet but found it to clog so i drilled a hole in the side and put the inlet there and blocked the top inlet.
it worked great but drilling the hole was a nightmare because of the angle and because i only had a hole saw

[Jonnynadeau]

I think I know what your saying, after we get out of this -25 degree F weather I think I'll try my hand at building one. I'll post pictures some where whether its successful or not. I've got a fair amount of MDF dust to clean up anyhow! lol