J. Phil Thien's Projects

Do you recall if the Rikon impeller has a forward curved, backward curved, or straight impeller blade design?  The HF blower I just bought has the forward curved design.  My understanding is that this is to gain CFM at the expense of pressure and energy usage.  Reverse curved blades are just the opposite.  This was tough to grasp initially, but now it makes a little more sense.

I did some more digging through the forum and found where this configuration has been proposed before.  If anyone has done this type of setup would care to comment on its pros and cons, I'd really appreciate the input.

I took advantage of the holiday sales and picked up a 2 HP HF Dust collector.  I'm working out how to use its parts.  See my design concept picture.  It is lacking the framework to support the motor, empty the can, etc.  I have a lot of experience fabricating steel framework, so that part is easy for me.  I will weld together a tubular steel frame.  The idea is to attach the HF blower directly to the top of a Thien separator then fabricate a smooth rectangular 90 to direct the blower output into a cartridge filter.  I have ordered one of the clear Huskee 32 gallon trash cans from webstaurant.com to use under the separator so I can see how full it is.  My experience with the first two separators I've built for my Shop Vac leads me to believe that I won't need the big HF ring or the plastic bag.  I don't expect anything but fine dust to make it past the separator.  The box shaped area under the filter represents a drawer that would catch whatever dust does fall from the filter when the blower is switched off.  Please feel free to comment, if this has been tried and has problems, I'd rather find out now.  Thanks.

I just bought one of the HF 2HP Dust Collectors.  I'm planning to mount the motor/blower part on top of a separator then exhaust to a cartridge filter.  I'm very interested in the mods you have made.  Did you replace the impeller because you couldn't get enough airflow?

Don,

I did pretty much the same thing with my shop vac.  Since my shop vac had a cylindrical reservoir, I placed it directly on top of the Thien separator where you have your bucket then put a can under the separator.  You should now consider upgrading your Shop Vac filter.  See my post here, at the end is the filter info. http://www.jpthien.com/smf/index.php?topic=1201.0

Lance, It looks like the end of the pipe that first hits your form is cut square across with a pretty sharp edge.  Could it be trying to dig into the form?  I wonder if easing that edge might allow it to follow the form more easily.

This new separator works even better than the first.  There is more suction.  It is quieter.  And, I think it has better dust separation too.  I know it's unscientific, but with the first separator I could vacuum off my floor mats without them sticking too much.  Now I have to stand on one end to clean them off.  The dust separation seems better, but it is hard to tell because both of them work great.  So, I'm ready for an extended test.  I have inserted the new .3 micron filter and will go back to my woodworking knowing that when I'm catching sanding dust off the lathe or cleaning up the shop, I'm not just stirring the fine stuff around anymore.  I may have to re-prioritize some money and get one of the cheap 2 HP dust collectors now that I know it could be made to work as well as an expensive one.

Here are pics of my test and a shot of the filter label.  I'm really happy to get it.  About 20 bucks at Lowes, what a deal.

About a gallon of mixed sized dust, all but a puff or two of really fine stuff stayed in the can.

P.S. Phil, that small donation I made was some of the smartest spending I've done all year.  Thanks for your ideas.

I can't quite tell from the picture, are you using a solid material PVC pipe or the cellular core type?  I was going to make a wooden bell-shaped form on my lathe and push the pipe onto it using the tailstock while applying heat with a heat gun while slowly rotating.  When I went looking for pipe yesterday, all I could find was cellular core schedule 40.  I wanted the thinner DWV schedule 20 that looks like a more solid material.  I don't know if it really matters but, the solid material seemed more promising.

My first separator was just thrown together without much finesse.  I just wanted to be sure I could make it work.  It works really well.  Not content to leave well enough alone, now I've got the second one done.  I tweaked the design a little.  I switched to 1/2 inch plywood for the top and bottom.  Since I'm using a 2.5 inch Shop Vac hose for the inlet,  I tapered the inlet port so that the rectangular cross sectional area where the air enters the cyclone area matches the area of the round inlet.  In my case the transition is from a 2.25 inch round hose to a 1.75" x 2.25" rectangle.  I also increased the outlet port diameter to 3 inches ID.  I know I'm messing with a tested design, but in my case I have my Shop Vac sitting directly on the top hat.  It seemed to me that having the 2.25 "outlet added additional resistance.  I also thought that by increasing the outlet size, I could reduce air velocity at the outlet and maybe pick up less of the fine sawdust.  Probably should have just left it alone, but that has never been my way.  I should be able to test it tomorrow.

So far it is holding.  I built a new top hat today and used the first one to clean up.

I know it's ugly compared to some of the other builds on this forum, but I'm really happy with this separator's performance.  However, the metal trash can would make a loud bang whenever I blocked the inlet.  Since I'm using it as a vacuum, this happened quite often.  I nearly jumped out of my skin the first time it happened.  I made a simple common sense mod that took care of the problem.  I put an OSB ring half way down inside the can.  Right now it is just a press fit.  If it needs a more substantial attachment, I'll use some screws or something to anchor it.  I know its not much of a mod, and it may have been done before, but I hope it is useful for someone.

I'm a long time woodworker who is tired of sweeping up sawdust.  I've had a Shop Vac for years, but typically only use it to get where the broom can't.  I've long wanted a real dust collection system, but haven't had the budget.  A month or so ago, I stumbled across this wonderful thing called a Thien baffle.  I could afford that!  Over the last few days I've built my first.  I had everything I needed in the shop so it cost me nothing but scraps.  I used a 30 gallon galvanized steel trash can, a tophat Thien separator, then set my 10 gallon shop vac, minus the wheels, on top of that.  I cut a hole in the bottom of the shopvac and gasketed it directly to the top of the separator.  It works really well.  There is never any sawdust in the shop vac, but fine dust is getting to the filter.  Once, the design is done, I'm going to replace the old ShopVac filter with one of the Gore Cleanstream fiters to improve filtration.  That's all for the introduction, I have some questions on refining the separator, but I'll post those in the separator forum.  Thanks to all, especially Phil for sharing his hard work with the world.