News:

SMF - Just Installed!

Main Menu
Menu

Show posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.

Show posts Menu

Messages - archiboy

#1
So after reading most all the threads on this forum and pondering the pro and cons of many designs I've finally taken the first steps in my first top hat solution. Thanks to all that have posted solutions and reported on successes/failures.  And most of all thanks to Phil for hosting the forums and starting the whole concept!

I have a few design perimeters that make my solution unique. I want to put my top hat and Thien collector up in my rafters to save floor space.  I'm in a climate that allows for rolling my DC outside about 80% of the time.  So I plan to have a WYE after the top hat that allows for the DC motor and filter to be outside my shop or inside depending on weather. I plan to put the DC on a switched outlet so I can control the power to the DC regardless of its' location.

Due to space considerations in the rafters I plan to modify the top hat to be partially or fully enclosed in the top section of the trash can.  I'm going with a clear trash can so I can easily monitor how much debris has been collected. The plan is to permanently mount the can into the rafters and side mount a 2-1/2" hose to the bottom of the can.  That will be used to hook up a traditional shopvac to empty the can periodically. I've attached an image of the first step to illustrate the overall concept.  The image shows the base of the top hat that has been fabricated to sit inside the trash can.

My next step will be to route the 270 degree debris entry slot.  I intend to start by introducing 3 or possibly 4 veins slopping in the direction of air-flow.  The veins will be routed from the source plywood and tapper from a sharp edge (1/8") to a 1/2" at the base.  The goal is to add some structural integrity to the floor (that others have resorted to supporting via all thread). I haven't found anyone who has tried to introduce veins and wanted to ask before I waste a bunch of time routing the veins if others think it will/won't work.  The plan B solution is to remove the veins and add in all thread if necessary to support the floor.

I also plan to follow the lead from others, including retired2, to use a rectangular entry into the cyclone transitioned to 5" round. And using a bell exhaust to the DC. My DC is the standard HF model and I'm currently installing mostly 5" ducting in my shop. I spent most of my spare time this summer building the shop. I've got it enclosed now and dust collection is the next major project to complete.  The shop is small - 9'x16'. The ultimate goal is to be build a CNC router table and floor space is at a premium. Hence the goal to get the DC system outside and in the rafters. 

TIA for any input/suggestions.
#2
Thanks for the quick responses!  Makes sense that the high velocity air needs to be above the baffle.
#3
Thien Cyclone Separator Lid Discussion / Hybrid design
August 26, 2011, 07:18:34 PM
I can't leave well enough alone... I am not an engineer, I'm an engineer's worst nightmare, an architect... I've read over this site and spent the last couple of days pondering the 'Thien' concept.  I studied the video from the user who built the top hat solution.  It struck me that as brilliant as the Thien design is, it's a 2 dimensional solution. So I started thinking about how to use the depth of the 'hat' to reinforce the airflow and create a better vortex - while still using easy to assemble parts.  So, I'm asking for input before I waste a bunch of time and materials going down a road that other's may have already tired and failed doing.  The basic concept is to transition a 6" inlet pipe to a 6" flex hose that follows the contour of the 'hat' cylinder. The flex tube should also drop a full 6" over a 270 degree turn.  So the end of the flex hose would end up under the 'Thien' deck or panel. Also the bottom outside quadrant of the flex tube is being proposed to be removed.

I've attached a sketch of the proposed design.  I hope to post a rough animation of the design to my web site in the next 24 hours.

So to those more knowledgeable with the aerodynamics of the task of particle separation I pose the question: Is there any merit to the proposed concept? Or does the vortex need to start above the 'Thien' deck for the device to separate effectively?