5", Rectangular Inlet, Bellmouth Outlet with Air Straightener, Top Hat Separator

[retired2]

I am curious if by adding the stiffener like you did wouldn't that cause added stress or flex on the 1/4 Hardboard?  ???

You're pretty sharp Don!  Without the stiffener, the baffle was a little springy and I'm sure it would have vibrated.  With the stiffener and the added weight, it sags just a tiny bit, but I suspect over time it will droop more.  So, I've purchased a 3/16" threaded rod that will be added to support the loose end.

Regards

[Don_Z]

Well, as since I am building yours verbatim except I am using 1/2" MDF (love the design), I got to thinking when I routed out the hardboard and saw how flimsy it was with the material that was left to support it. So the thought of adding more material to it wasn't clicking right in my head. So I was thinking that rather than cut out the hole completely on the bottom hole of the sandwich completely, what if you just routed out the 1 1/8" cutout and beveled that edge from underneath? Just thinking out loud about this and working on it between stages of my kitchen project.

Don Z.

[retired2]

So I was thinking that rather than cut out the hole completely on the bottom hole of the sandwich completely, what if you just routed out the 1 1/8" cutout and beveled that edge from underneath? Just thinking out loud about this and working on it between stages of my kitchen project.

Don Z.

I think that would work fine.  There were two things I was trying to accomplish with my baffle design and both created construction problems.  The first was to avoid having a ledge along the outside wall of the drop slot.  Of course, that meant there couldn't be any dado to hold the bottom edge of the plexiglass.  The second thing I wanted was a thin baffle because I seem to recall Phil saying thin baffles worked better that thick ones.  Of course a thin baffle needs to have some additional support, so I am stuck with an internal post that I would have preferred not to have.

[Don_Z]

I am hoping to achieve a compromise of that with the use of a thicker bottom and some creative routing. So, have you tested it yet?

[retired2]

I am hoping to achieve a compromise of that with the use of a thicker bottom and some creative routing. So, have you tested it yet?

Sorry to say Don, I'm not even close.  My garbage can and top hat design, allowing for raising and lowering the outlet pipe for different test conditions, won't fit under my 50-760 dust collector.  So, today I was out buying material to remove the dust collector from the wheeled stand and raise it up on fixed supports.  Tomorrow the collector goes into the paint shop for priming, a day later a coat of paint, and then the plexiglass gets attached.  I suspect I'm a week away from testing.  I'm as slow as a snail, but I prefer to think of it as methodical!!

If being slow isn't bad enough, today my wife found some curtains that she likes better than the ones I just hung for her yesterday.  And as you might expect, the rod has to be moved.  I don't dare complain or she will shut off all shop purchases.

[Don_Z]

Do I know how that goes.  >:(  I have been remodeling our house now and to take time away from that to work on this separator is like stealing from Fort Knox! It has made me rather proficient at multitasking I must say. So what color are you going to paint your DC and are you going to paint the Separator as well? I was thinking of painting mine in a faux metallic finish and giving it a retro 50's post modern machinery look to it. I might even throw in some useless dials and gauges on it as well to have fun with it.

[retired2]

Do I know how that goes.  >:(  I have been remodeling our house now and to take time away from that to work on this separator is like stealing from Fort Knox! It has made me rather proficient at multitasking I must say. So what color are you going to paint your DC and are you going to paint the Separator as well? I was thinking of painting mine in a faux metallic finish and giving it a retro 50's post modern machinery look to it. I might even throw in some useless dials and gauges on it as well to have fun with it.

Sorry Don, I said my collector is going into the paint shop, but what I meant to say was my separator.  And the "paint shop" is a pair of saw horses where the separator will sit while I brush on "Smoke Gray" water-based paint.  I'm not going to paint the floor of the separator because I want to keep it slick.  I will probably apply a heavy coat of paste wax to the tempered hardboard.  The will provide some moisture protection while keeping friction losses down.

[Don_Z]

Don't you think the paste wax will get gummed up from the dust? I was thinking that with a coat of paint and then a lacquer topcoat, that would keep it slick enough. Hmm. Aren't we just overengineering this little number?  ;D

[dabullseye]

i like the idea of the adj outlet pipe. im just wondering how you are gonna hold the pipe in test positions and still get it sealed. or are u just gonna use some rtv after u do some testing.
i was thinking of a large o-ring and a hose clamp or one of those spring loaded clamps

[retired2]

i like the idea of the adj outlet pipe. im just wondering how you are gonna hold the pipe in test positions and still get it sealed. or are u just gonna use some rtv after u do some testing.
i was thinking of a large o-ring and a hose clamp or one of those spring loaded clamps

I'm plannning to use Mortite caulking cord.  It is dirt cheap, easy to mold, will be air tight and can be removed easily.   The Mortite will be used only during testing.  Once I decide what works best, I will caulk the pipe with construction adhesive.  If I must remove it I still can, but at that point it is pretty much permanent.

[Don_Z]

@Retired2 - I just wanted to let you know that I have finished my build from your design and plans and have tested it out. The performance was exactly as I had hoped for and even though I didn't permanently seal everything or attach the lexan securely or have the filter and lower bag attached. Basically I just hooked the motor up while it was on my bench. I took the hose and buried it in a bucket of fine dust and hardly anything came out. I can hardly wait to get it painted and permanently sealed up to see what it can do. I appreciate yours and everyone else's  openness with your builds and info.

DonZ

[retired2]

@Retired2 - I just wanted to let you know that I have finished my build from your design and plans and have tested it out. The performance was exactly as I had hoped for and even though I didn't permanently seal everything or attach the lexan securely or have the filter and lower bag attached. Basically I just hooked the motor up while it was on my bench. I took the hose and buried it in a bucket of fine dust and hardly anything came out. I can hardly wait to get it painted and permanently sealed up to see what it can do. I appreciate yours and everyone else's  openness with your builds and info.

DonZ

Congratulations Don!  Glad to hear it's working out.  What's your early assessment of the bellmouth?  Did you compare it to a straight pipe?

I knew I wasn't going to be first to complete the construction of this design (I'm quick with ideas, but slow on execution), but at least the positive report will give me the motivation I need to work harder on my own.  If you had told me it didn't work worth a hoot, I might be in the shop cutting mine up for scrap.   

[Don_Z]

Well, I did not use the bell-mouth, mine is on the way, but by using your top opening design, it will allow me to install it later. but the biggest advancements that I felt were a benefit was you inner ring rib cage and the hardwood supports at the ends that capped the lexan. Rather brilliant.

[dabullseye]

looking at your metal intake do u think it would have been better to extend it into the chamber and cut it off on the same cir. as the inside dia. im just wondering what kind of turbulence it is at that point from your test. 

[dabullseye]

one other thing i see where you added a 3/16 t-rod. what do u think of just attaching the rod to the bottom of the can so that the baffle will just sag and rest on top of rod