[WoodES]

day 1

And so.. my personal Thien Baffle challenge begins.
1/2" MDF (i have 2 of these 4×8' sheets..might as well use them). First time ever working on MDF with a power tool. To date… MDF 1, Eric 0 for dust control.
This baffle will sit on top of a 55 gallon plastic drum, be 12" high (to allow more separation and swirling action), and same as many other Thien Baffles out there with a couple differences:

1.) I used a 45 degree chamfer bit on the outer lip to give falling particles no gap space against the 1/16" lexan I'll be installing. This has increased my gap space another 1/2" from the desired 1 1/8" cut out end result (right now, the cut out is 2 1/8" because I'll be laminating 1/8" hardboard on top of the MDF to extend 1" into cutout area). Shall see how this messes anything up.

2.) routed a 1/16" wide 1/8" deep slot at the top of the chamfer for the 1/16" lexan. Made it all the way around and was pulling it backwards to blow out the dust inside the groove and the tip of the bit broke. Darn it.

I am thankful to have picked up a MicroFence edge guide with circle jig at an auction for $20 will everything intact, as this thing is a wonderful perfect router circle jig and with the help of a hand clamp a wonderful circle jig marker as well.

Looks like my layout…..

I used some of the inexpensive orange box pine faced finish plywood for mine. At first I thought your slot was too big, but then read that you were covering with 1" hardboard. Should work good.

I routed a groove on the bottom to match the diameter of the barrel and as it has a rolled edge, a cove bit makes a nice fit.

One other thought. I screwed the walls to the vertical supports. I didn't want the suction to implode the walls. No problem so far.

 

[WoodES]

day 3

I purchased the 1/16" lexan poly-carbonate with dimensions of 16" x 60" for $32. Routed a 1/4" groove for the lexan to sit in, top and bottom. Cut all the support pieces and slapped it all together for a dry fit run. Here is the result:

So far… it does not look like I'll win a beauty contest with it, but it will fit my utilitarian funtion. I made alot of mistakes and errors which have given me much needed experience in working on MDF, using Microfence jig, first time really using my bosch 1617 router, etc.
Next will be cutting a 13" diameter thru the top of the baffle for the 7" bellmouth outlet, assembling inlet 6" (well, actually 8" x 4.5") port, and doing a function test. Who knows, might not have to silicone or caulk or whatever to seal up the chamber as everything was a good tight fit.
And notice.. the baffle cut out arc has been changed from my previous error: the opening now starts much later and the end stops right before the inlet.

Looks like a winner to me.

I used clear duct tape on mine and I have no glued parts. This allows me to access the interioror replace the poly-carb should it be necessary.

My slot starts closer to the inlet and stops earlier. I have observed that the chips drop out of the air flow and the beginning of the slot and less so at the end.

 

[WoodES]

day 3

I purchased the 1/16" lexan poly-carbonate with dimensions of 16" x 60" for $32. Routed a 1/4" groove for the lexan to sit in, top and bottom. Cut all the support pieces and slapped it all together for a dry fit run. Here is the result:

So far… it does not look like I'll win a beauty contest with it, but it will fit my utilitarian funtion. I made alot of mistakes and errors which have given me much needed experience in working on MDF, using Microfence jig, first time really using my bosch 1617 router, etc.
Next will be cutting a 13" diameter thru the top of the baffle for the 7" bellmouth outlet, assembling inlet 6" (well, actually 8" x 4.5") port, and doing a function test. Who knows, might not have to silicone or caulk or whatever to seal up the chamber as everything was a good tight fit.
And notice.. the baffle cut out arc has been changed from my previous error: the opening now starts much later and the end stops right before the inlet.

Good, remember now you have very little restriction on the inlet side. Should you ever have a clog, or heavy chip load the weakest point will give. It could be the lexan.

 

[WoodES]

day 3

I purchased the 1/16" lexan poly-carbonate with dimensions of 16" x 60" for $32. Routed a 1/4" groove for the lexan to sit in, top and bottom. Cut all the support pieces and slapped it all together for a dry fit run. Here is the result:

So far… it does not look like I'll win a beauty contest with it, but it will fit my utilitarian funtion. I made alot of mistakes and errors which have given me much needed experience in working on MDF, using Microfence jig, first time really using my bosch 1617 router, etc.
Next will be cutting a 13" diameter thru the top of the baffle for the 7" bellmouth outlet, assembling inlet 6" (well, actually 8" x 4.5") port, and doing a function test. Who knows, might not have to silicone or caulk or whatever to seal up the chamber as everything was a good tight fit.
And notice.. the baffle cut out arc has been changed from my previous error: the opening now starts much later and the end stops right before the inlet.

I am not sure what pressure setting would be used for relief. I suspect it would be rather low. As you have a large lexan surface area, even a low pressure on a large surface generates a large force that you would have to support with the grooves.

Example: 20" dia baffle x pi (3.14 not cherry) gives you ~60" circumference x 16" height, resulting with an inner surface area of 960 sq in. You multiply that by your assumed psi and you get the force that must be resisted by the lexan. 1 psi provides 960 lbs, 10 psi 9600 lbs. etc.. All of this is suction and the vertical supports contribute nothing to support the lexan for this suction pressure.

As there are many examples of thin gauge metal duct collapsing under the suction pressure of a dust collector, one can envision a similar situation with a large separator.

 

[WoodES]

day 4

Found out, I have a 6" inlet on my Grizzly 3HP dual bag dust collector, not a 7" like I "assumed" I had. Luckily, I have 6" HVAC parts to use up for today. But it did force me to redo hastily the top plate from 7" to 6". I also cut out a 14" with 45 degree bevel for a temporary plate used to fine tune the chimney height, for future cleaning of interior lexan, and if I decide to go forth with the bellmouth it will be easy to install.
Here is the latest picture of my progress. Nothing is sealed, siliconed, caulked, or grey pastey stuff on the HVAC duct work. And yet.. when I fire it up, it works Tossed a handful of planer shavings in and to the eye.. it appears 100% of the shavings made it into the barrel.

Well that just sucks! Congratulations….

Always fun when the project throws a curveball.

 

[WoodES]

day 4

Found out, I have a 6" inlet on my Grizzly 3HP dual bag dust collector, not a 7" like I "assumed" I had. Luckily, I have 6" HVAC parts to use up for today. But it did force me to redo hastily the top plate from 7" to 6". I also cut out a 14" with 45 degree bevel for a temporary plate used to fine tune the chimney height, for future cleaning of interior lexan, and if I decide to go forth with the bellmouth it will be easy to install.
Here is the latest picture of my progress. Nothing is sealed, siliconed, caulked, or grey pastey stuff on the HVAC duct work. And yet.. when I fire it up, it works Tossed a handful of planer shavings in and to the eye.. it appears 100% of the shavings made it into the barrel.

Seems like any leakage could be fixed with duct tape. After all, duct tape is the universal solution….

I think there are female couplings available that may do the trick. That would eliminate all but one of the backwards fittings.

I had to make up a male - mail metal coupler for the transition drop to the table saw. Found a fitting that fit both the 6" pvc and the 6" hose. I rigged up a support to take the weight of the hose. Works well.

 

[WoodES]

day 4

Found out, I have a 6" inlet on my Grizzly 3HP dual bag dust collector, not a 7" like I "assumed" I had. Luckily, I have 6" HVAC parts to use up for today. But it did force me to redo hastily the top plate from 7" to 6". I also cut out a 14" with 45 degree bevel for a temporary plate used to fine tune the chimney height, for future cleaning of interior lexan, and if I decide to go forth with the bellmouth it will be easy to install.
Here is the latest picture of my progress. Nothing is sealed, siliconed, caulked, or grey pastey stuff on the HVAC duct work. And yet.. when I fire it up, it works Tossed a handful of planer shavings in and to the eye.. it appears 100% of the shavings made it into the barrel.

Periodically tap it with a broom handle with the dust collector on.

With a little work, the male end can be spread. Worth a try at that price…

 

[WoodES]

day 4

Found out, I have a 6" inlet on my Grizzly 3HP dual bag dust collector, not a 7" like I "assumed" I had. Luckily, I have 6" HVAC parts to use up for today. But it did force me to redo hastily the top plate from 7" to 6". I also cut out a 14" with 45 degree bevel for a temporary plate used to fine tune the chimney height, for future cleaning of interior lexan, and if I decide to go forth with the bellmouth it will be easy to install.
Here is the latest picture of my progress. Nothing is sealed, siliconed, caulked, or grey pastey stuff on the HVAC duct work. And yet.. when I fire it up, it works Tossed a handful of planer shavings in and to the eye.. it appears 100% of the shavings made it into the barrel.

Used the bigger hammer solution, I like it….