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 - BradD

#1
Quote from: jgt1942 on March 15, 2014, 03:44:05 PM
Sketchup will work. click File > Import > drill down to where the file is located. After loading the file click Save or Save As and save the file.

IrfanView will also work but you may need a plug-in which will be identified when you open the file.

AudCad will work - there are free versions you can find on the web.

Good info, JGT. Thanks. I wasn't sure about Sketchup, because I don't use it. IrfanView is a pleasant surprise. I've used it in the past, but never knew it would do DXFs. DesignCad 3D Max is my CAD of choice. It makes and reads DXFs.

Thanks again!
Brad
#2
Hi, Bernard. Thanks for the kind words.

The walls are acrylic. I made the choice on very unscientific grounds:  It is reasonably priced and available in Home Depot stores.  A 24x48x.090 sheet is under $30. This link will get you to the product:

http://www.homedepot.com/p/202038048?N=5yc1vZbrdgZ1z0th74Z1z0xux8Z1z0z676Z1z0z6cb

I ripped an 8" wide piece of the sheet using my table saw. Set the blade just high enough to cut through and keep it flat on the table. I also recommend using a zero-clearance table insert.

Good luck on your build. Don't stress on the minutiae, follow the general guidelines and you'll end up with a good functioning separator.

Regards
Brad
#3
Very nice! Pretty barrel.

Bungee cords will free up those clamps.

Just posted results of my first emptying.
http://www.jpthien.com/smf/index.php?topic=1080.0

Regards,
Brad
#4
I just filled up my first bucket load, and I wanted to show everyone the results. Just to jog your memory, it's a 10-gallon bucket from a Rockler Dustright Vortex. Wood dust comes from the CNC router, table saw, floor sweepings, etc. Wood is mostly a mixture of MDF, plywood and poplar.

Here's a top view of the bucket contents:

The inlet is over the lower left, and the swirl goes clockwise.

More of an angle:

The low point is under the inlet, the high point about halfway around. The center of the bucket is the lowest point with a conical wall around it.

Here's the dust bag dump:

This is about 2 cups of very fine wood flour.

another angle:


Here's a handfull:

This is very fine dust. Silky soft with no lumps or bigger pieces.

Overall, I am very happy with these results. The shop is staying cleaner and airflow remains high with so little dust going to the bag.

Thanks for looking!
#5
Let me start by saying I don't know nothin' about what I'm talking about. I took Fluid Mechanics about 40 years ago, and I've forgotten more than I ever knew. The math went totally over my head.

Now that we have that straight, it looks to me like you need to do some work on the inlet, if that's it on the lower left of your template. I say this because if air is flowing up from the bottom, it almost immediately gets deflected about 45*. If either of the last two "ifs" are incorrect, then somebody tell me so I don't embarrass myself any further.

You could continue the outer spiral around to where you could inlet your air more or less at a tangent to the spiral.

Also, there's a post around here where someone got good results with a spiral-in only on the last little bit of the wall, just before the intake.

I'll look and if I find it, I'll edit in a link.

Brad

Edits:
This is the post I was thinking of:
THE CASE FOR A "TWEAKED" RECTANGULAR INLET Reply #68 in 5", Rectangular Inlet, Bellmouth Outlet with Air Straightener, Top Hat Separator: http://www.jpthien.com/smf/index.php?topic=563.60. The entire thread is a "must read."


Others of interest:
Short discussion on scroll (spiral) design: http://www.jpthien.com/smf/index.php?topic=1055.0
"Vortex trip" Reply #5 in http://www.jpthien.com/smf/index.php?topic=1055.0
#6
Hey, TVMan. Looks like you're trying to answer the same question I had. I just went ahead and did it. I was quite happy with the results. My build may not be (probably isn't) the ultimate in fines removal, but I'm not going to complain. I have a 4 inch gap between the window/wall and the edge of my baffle plate support, with the "peninsula" falling under the 120* no-gap area. As I mentioned in my write-up, I would move that area about 30* clockwise. If you're using 3/4" ply for the base, then it would also be good to narrow the peninsula a bit, too. Take the extra meat off on the side where the duststream is about to meet the intake.

I noticed some dust buildup on the peninsula at the end of the exit slot (1.125" wide), indicating to me that the peninsula was interfering with air flow. I took a wood rasp to the end of the slot and created a downward ramp. I ass-ume this made some small performance improvement. At least now, the dust stream hits a ramp instead of a wall.

Quote from: tvman44 on February 05, 2014, 05:08:18 PM
Bulldog8, how wide is your slot?  I am thinking about a 3/4" wide slot.
The brains behind this contraption seem to think a 1-1/8" slot is optimum. I don't know if that dimension is scientific or not, but I say go with it.

I get much more (subjectively) air flow than I did thru my old separator, and the dust removal is phenomenally better. I say give your ideas a try. What could go wrong?  ;D

BTW, did you find a program to read my DXF file?

Brad
#7
Before I get to the test video, I want to show a couple of pictures of the Rockler separator, showing why it's not an optimal solution:

The separator lid:


As you can see, the inlet blows sawdust straight at the outlet elbow. Also, the airflow has to make a 180* turn to leave.

Looking at the bottom of the bucket:


Here you can see that the swirl goes all the way to the bottom, creating the cool looking sawdust-scape.

Here's video of the first test run:
http://youtu.be/iTvZFy-N6Es
Success! ;D

Very little dust got to the filter bag. This picture shows what got thru:


I'm afraid my floor is the same color as sawdust, so it's hard to see. I'll say there's less than a quarter cup of dust that went to the bag. Remember, this is MDF dust, so it's pretty fine to begin with. I'm very happy with the result.

According to my Kill-a-watt, the DC draws less current now than with the old system. This is counterintuitive, as it stands to reason that more air moving = more amps. There is no doubt in my mind that there is more air moving than before. I should have noted the voltages before and after. Does anyone have a thought on this?

What needs improving? The edge of the baffle plate in front of the inlet sticks up and catches dust and larger chunks. I think I'll make a piece to go from the inlet ramp to the edge of the baffle plate.

Also, I would move the baffle plate support cutout more clockwise. I think if the baffle slot went a little farther around, collection might go faster.

I'm also going to make a clamp-y thingy to hold the outlet tube more solidly.

Phil, thank you for your separator design. It is a modern marvel. Check your email, you've got some bucks on the way.

Thanks to everyone looking. I welcome questions and comments.
Brad
#8
Quote from: tvman44 on February 17, 2014, 01:24:07 PM
What program do I need to open a .dxf file?

Most CAD programs will work. I'm don't know for sure, but Google Sketchup might work, and it's free.

Also try googling "dxf viewer".

Can anyone else help tvman44?

Brad
#9
The first step was to cut the parts on the CNC. The material is 3/4 MDF, just because that's what I had. The MDF did provide me with plenty of fine dust for testing.  :P

The YouTube vid runs a little over 20 minutes with lots of CNC action: Enjoy!
http://youtu.be/wNUUT9ZkBcs

With the parts cut, it's time to assemble.
Bending the window, loose assembly:


Different angle:


I don't think I allowed the acrylic to heat enough to become really bendy. It formed a big arc with the ends about a foot off the table. This turned out to be a good thing, as the window later cooperated by springing tightly into its groove.

As I mentioned before, I sanded the underside of the baffle plate to thin the edge:


Edge-on view:


Fully assembled and ready to test:


Next up: Testing, results, recommendations.
#10
After studying this forum, I was pretty sure I had absorbed enough to draw up a plan that I could build on my CNC router that would eliminate parts, incorporate several important design principles and provide smooth airflow plus provide enough adjustability to experiment with different settings of the baffle plate and the height of the exhaust.

Let's look at a top view of the base plate:


This is a 2H design (4" hose inlet, 8" nominal height). The inlet transitions from 4"D to 2x8" rectangle, and intersects the window at a 10 degree angle. The window sits in a rabbet that puts it very near the edge of the baffle cutout. The baffle cutout is 1/8" off the bucket I.D. The base provides a large support area for a thin hardboard baffle plate, while staying back from the edge.

Now, lets look at a top view of the top:


The top outline is a copy of the base. The top provides a groove for the window, and an outlet hole for the exhaust.

The baffle plate looks like this, in 3/16 hardboard:


The baffle plate provides a 1-1/8" gap for the dust to fall through. The bottom edge gets beveled on the belt sander to reduce the thickness at the very edge by about half the thickness of the hardboard.

I'm attaching a DXF file of the drawings for your reading enjoyment.

Next: build photos and video
#11
Hi Everyone!

My goal with this build is to improve the dust collection in my home shop, using as many existing resources as possible.

My "before" system is a Rockler wall mounted dust collector similar/identical to their current DustRight model connected to their 10-gallon separator with 2-1/2" hose connections. The shop contains a table saw, radial arm saw, 2 sanders, and last but not least a CNC router. The 2 saws connect directly to the DC through 4-inch hoses and blast gates, not using the separator. The sanders have 2-1/2 connections, and the router has handheld 2-1/2" dust collection. (You'll see in the videos I took.)

The 2-1/2 inch collection path is Dust Collector -> Elbow -> Wye -> blast gate -> 4" flex hose, 10 or 20 feet as required -> 4 to 2-1/2 reducer -> 2-1/2 inlet to separator -> 2-1/2 outlet to 10 or 20 feet of 2-1/2 hose, as required -> nozzle or machine connection. This setup is also used for floor cleanup. As you can imagine, by the time you get to the end, there's not much suction left.

Next: The new design. Stay tuned!
#12
Howdy all. I found this site through Mathias Wandel's woodgears.ca woodworking website. I'm a hobbyist woodworker with a CNC router that makes plenty of dust, which I would like to do a better job of collecting. I'll be posting a build I just completed, using the CNC. Watch for the  "Tophat CNC Design & Build" topic.

Nice place you have here, Phil. And your separator is fantastic!

Best to all,

Brad