J. Phil Thien's Projects

Quote from: pitbull on July 27, 2011, 05:58:28 PM
The ones I purchased are not like that. They are smooth in the direction of flow and are made in the USA.

I found them to be cost efficient and very well made. The shipping was actual charge and not a flat rate. Everything came as I ordered and I felt I got a deal.
http://www.kencraftcompany.com/Dustindex.htm

Interesting!  I'm familiar with Kencraft, but I've never purchased from them.  I wonder how the wye's from the Lowes and Home Depot are made?  I'll have to check them out the next time I'm there.

Chuck, I can't say if these wye's are typical or not.  All I know is I have purchased them from two different sources, and while they are fabricated slightly different, they both have tabs. 

The "flange" you noticed is an integral part of the branch pipe, and what appear to be rivets are actually tack welds.  The tabs are all from the straight run of pipe.  I think the tabs are intentionally formed to add strength, and some strategic ones are also tack welded.

I'd be curious to hear from other members who are using metal pipe whether or not their 45 degree laterals are fabricated similarly.

 

When I decided to make my DC stationary and pipe everything to it, I knew I would be stretching the capacity of my Delta 50-760.  So, I decided I would do everything I could to minimize line loss and turbulance.

Below is a picture looking into the lateral branch of a typical HVAC wye.  As you can see, the fabrication method results in many small tabs
facing into the direction of air flow.  It seems to me these tabs are a source of unnecessary turbulance and increased friction loss, and possibly even a birds nest if you are conveying heavier shavings or stringy material.

The second photo shows a wye after I covered the tabs with "Lab Metal", and sanded it smooth.  This modification may only make a tiny improvement in the performance of my system, but it has to be better than stock wyes.

Quote from: pitbull on July 25, 2011, 06:01:57 AM
I was going to be coming of a 6" line and splitting it into a 4" and 3" then down to 2-1/2". I have run previous tests with a 2" line and all have been unsatisfactory. However, I was just wondering if you got different results. I think for the small ducting like that I will stick with a shopvac.

Thanks

If your application is a piece of equipment that you only plan to have one 2" connection, I would agree a shop vac would be much better than a DC. 

In the case of my bandsaw, the 4" connection is doing 90% of the work and the 2" is just catching a few fines that ordinarily might get away.  I'm not sure what the SP is for your shop vac, but typically they can run nearly 8-10 times the SP of a dust collector.

Quote from: pitbull on July 24, 2011, 02:27:05 PM
How well does the little 2" line suck. I know you have it on a wye...I was considering adding something like this for a dust hood, but fear the dust collector can not give me enough airspeed to pull dust from the 2" line.

Well, it does what it needs to do, but it is a little on the weak side.  Now, I need to qualify that response.  My bandsaw is nearly 40 ft. of 5" pipe away from my Delta 50-760 DC, and that's not counting the equivalent losses for ells and laterals that are in the run.  That puts me close to the limits of what my DC can do, and I still don't have a Thein separator installed.  I'm keeping my fingers crossed.

The wye you see in the photo is also a reducer.  It is a 5"x4"x3".  The 3" branch has a plastic reducer (3" x 2-1/2"), so the flex hose is 2-1/2" to the bandsaw.  At the bandsaw it reduces to 2".

My advice to you would be give your idea a try.  As long as the area of the two branches doesn't exceed the area of your drop line, you should get some benefit, but if you are starting with a 4" line, I'm not sure your going to get the kind of air flow you need if you split it further.

Regards


 

Quote from: RCOX on July 23, 2011, 06:51:33 PM
All good suggestions. Due to some extenuating medical circumstances with my wife I am limited on what I can spend, until we find out the expenses.

Rcox, sorry to hear your wife is dealing with medical issues.  I hope all goes well for both of you. 

Thirty-five years ago, when I bought the bandsaw in the following photo, no one ever dreamed of dust collection in a small shop as we know it today.  All you hoped for was a dust chute that put most of the dirt in a neat pile on the floor so it could easily be swept up.  Powermatic's idea of a dust chute on their 14" bandsaw was a 2" pipe stuffed in the throat just below the table top.  It captured about 50% of the dirt - the rest accumulated inside the saw until it started coming out every crack until there was dirt everywhere.

When I got my Delta 50-760 DC I figured this would be the easiest tool in my shop to contain the waste - NOT!  I really didin't expect my first attempt to work because I just hooked the full force of the DC to the 2" pipe and hoped for the best.  It sucked up the 50% of the dirt that the chute previously sent to a neat pile on the floor, but the other 50% still went everywhere.

So, I thought about the problem for days until finally I decided I needed a new dust port, a real one.  So, I took the steel door off the bandsaw and took it to a local fab shop and asked if they could burn a neat 4" hole in the door where I had marked it.  The guy I deal with said no problem.  He could see the pain that cutting a hole in my bandsaw was causing me so he advised me to take two aspirin and come back in the morning with several dozen assorted donuts for the guys in the shop.  That's all it cost me.  They did an nice job, but I spent the next few days recovering from the surgery.

This is a photo of my finished installation, but not the end of the story:



Once the two dust hoses were connected as shown in the above photo, dirt was still escaping around the throat just below the table top.  The lower blade guides were the problem.  They form two 45 degree ramps that were deflecting the dirt coming out of the blade gullets.  Here's a picture before my modification.



Now I had to figure out a way to capture the deflected dirt and redirct it to the 2" dust chute immediately below.  The solution was a small box that snugs up to the underside of the table and wraps around the blade and lower guides.  This keeps the dust from escaping the vacuum stream below.  Here's two photos showing the box and how it is attached.






So, here's the lesson.  If you've got an old bandsaw that throws sawdust around in spite of being connected to a good DC, cut a real port in a strategic location, and everything will work much better.  Take my word for it, you and the bandsaw will live through it!!

Actually Chuck, I think we are in total agreement.  He's got a great DC, but to get maximum efficiency out of it he has to give it more air.

Quote from: Vodkaman on July 22, 2011, 11:07:10 PM
Thanks Chuck.

Retired2 - I do agree. Quantifying results is the problem. I don't think a bank of pressure gauges is going to help either. I don't think anything can beat measuring dust in and dust out, repeated several times for consistency. I just wish I had the funds, as this is the kind of stuff that I love doing, ideas, building, prototyping and testing is my full time hobby. I am an amateur inventor, which means I don't get paid.

Even though we cannot prove any of the ideas, I still think that we should continue to collect them. Occasionally someone will suggest and idea that maybe seems insignificant, but will jump off the page. Also ideas generate ideas. So I say keep 'em comming.

Dave

Vodkaman, your comments make me chuckle because they put you among a group of people in this world, me included, who have a compulsive need to understand how everything works whether we truly need to know or not, and we are always on a quest to make them work better whether they need to or not!

I don't know how many times in my life a new aquaintence asks me "Are you an engineer?"  Most of the time it is asked in a way that is not necessarily intended to be a compliment.  It is more like "If you are an engineer that would explain your nutty obsessive complusive behavior and your need to fix things that ain't broke!"

Quote from: Chuck Lenz on July 23, 2011, 07:57:32 AM
I'm not so sure that an 8" inlet on the DC would support two 6" mains, I was thinking that two 5" mains would be more appropriate, a 5" line would support two 4" gates being open, but I wouldn't leave more then three open at a time on the whole system.

Chuck, my suggestion on 6" size was still based on the assumption that he is only running one machine at a time, so no matter how many 4" headers are coming into his accumulator only one is open at a time.  If that is how he is running his system, 6" headers are a good compromise because that size pipe and fittings would have significantly less static pressure losses, and it would be readily available at prices that are still reasonable.  By contrast, I doubt you could find much of anything in 7", and 8" probably gets a little costly and far exceeds the needs of his worst case user.

If he is running both headers open simulatneously two 6" headers only exceeds the capacity of the 8" inlet by about the same percentage as two 4" headers exceed a 5" inlet.

Rcox, you have a very good DC with far more capacity than the typical small shop.  I checked the Powermatic website and if I had the correct model, you have over 11 inches of SP.  By comparison my system is 1200 CFM and a little over 8 inches of SP. 

I have been building my system over that past year and only now am ready to build the separator, so I can't comment on what to expect in suction loss due the separator.  I can tell you I have one long run with pressure losses the just about reach the limits of my system, so if the separator adds a lot of loss, I may have problems.

Having said, that your test of your separator does seem to suggest a problem of somce kind.  I would not have expected much suction loss when it is close coupled and no other loads.

The other thing you should be thinking about replacing your 4" mains with at least 6".  You've got the equivlent of a fire truck pumping water through a 1/2" garden hose.  Snap lock pipe doesn't cost that much more than plastic pipe and you can get long radius ells.  I'm sure you don't want to start tearing out a system you just installed, but longer term that should be a goal.

Quote from: Chuck Lenz on July 21, 2011, 09:12:29 PM

Quote from: retired2 on July 21, 2011, 07:43:21 PM
I assume you have blast gates at each piece of connected equipment and only one of the 4" lines is open at a time.  If so, I don't know what two separators is going to do for you.

The reasons that I suggested two Separators is his Dust Collector has a 8" inlet, plus it moves alot of air. How big of a Separator drum to you think that you'd need to have an 8" outlet going to the DC and an 8" inlet in the Separator ? So I figured go with two managable size Separators, especially since he's useing two main trunks.

Chuck, I'm not sure I saw confirmation to my assumption that only one 4" line is bing used at a time.  If both 4" lines are operating at the same time I can see your point about two separators. 

However, if only one of those 4" headers is operational at any one time, then only one separator would be operational at a time, so why have two.

I must admit that DC does look like overkill for a system built of 4" pipe and I'm surprised that adding the accumulator and separator produced a noticable drop in performance.  It seems like we have a big air mover that is suffocating.

Rcox, If you only give your DC air from one piece of equipment at a time, try opening two blast gates simulateously, or even three, and see if the performance of your system improves. 

What's the SP and CFM rating on your DC?

The "vortex trip" might work, then again it might act like a snow fence.  If you live in the part of the country that uses these fences you know they cause the snow to drop out and drift on the downstream side of the fence.

As Phil points out, there are a number of ideas that might provide improvements in performance, but they are likely to be small and very difficult to measure or quantify.  For sure the improvements cannot be calculated with mathmatically formulas, so that means the ideas must be tested the hard way - build it!

Chuck, your concept might well be the next generation separator, the "Thein2"!!  It incorporates a rectangular inlet and Phil's idea of a turn.  Of course, I'm not sure we know what the turn should look like, i.e. what radii, what direction, and how far from the inlet?

When I get a little closer to actually cutting wood, I may take a drive over to my sheet metal fabricator and see how much a transition piece would cost. 

Quote from: RCOX on July 21, 2011, 04:29:49 PM
Phil: So many choices and with my limited knowledge of suction loss due to sharp radius turns, size of pipe restrictions etc. is enough to boggle my mind. I went with the 6" pipe size through the separator because it is 2.28 times larger area wise than 4" and I wanted to not have to completely replumb my shop. That would probably be the smart thing to do but at this time I am not in a position to do so. I work in maintenance and actually Vodkaman's approach is the way I do all my trouble shooting to repair equipment. There has been a lot of good info put out there and I will admit, I was looking for the easy way out. Give me the answer don't make me figure it out myself. I have been the most concerned about the accumulator knowing I should start by replacing it. Chuck had a very good thought about going with 2 separators but I have been down that path except, with the Rockler type setup, not your design. I think I will probably put my experience in troubleshooting to work and see where it leads. Maybe in the end I will have all new plumbing throughout maybe not, but I will have gained a lot of knowledge in dust control (good or bad).

Take a look at the photo below showing part of my DC piping.  In particular look at the manifold above the floor sweep and jointer.  Now imaging that turned upside down.  That is what you should build.  Get rid of the accumulator and put in two sweeping bends into two 45 degree laterals.  I assume you have blast gates at each piece of connected equipment and only one of the 4" lines is open at a time.  If so, I don't know what two separators is going to do for you.