Apply palm directly to forehead

[Bombarde16]

OK, admit it: Tool manufacturers don't give a !$#&@ about dust collection, do they? Sometimes it feels like their efforts are purely decorative.  This is the 4" port from my new Grizzly table saw. That cool-looking overhead hose that plugs into the blade guard? It's choking off 25% of the airflow from below the blade.  Coping saw and a Dremel to the rescue!  Since I'm plumbing my own shop, I've run a separate line for the blade guard hose and can give the underside of the table its full 4" port...or, at least it's 4" until it chokes down to 3" inside the saw.

[Chet]

Yea, that looks like a real "under thought out" design.  Wouldn't it be better for you just to replace the whole piece instead of cutting out the offending parts so all the dust has a clear shot at a successful trip to you DC collector?

[Bombarde16]

Just now, Chet said:

Yea, that looks like a real "under thought out" design.  Wouldn't it be better for you just to replace the whole piece instead of cutting out the offending parts so all the dust has a clear shot at a successful trip to you DC collector?

It certainly would. And, come the day that I get a 3D printer, that'll be project #427,584 on my list of things to print. In the meantime, it wasn't too bad to hack out the offending bits.  What's more irksome is that it chokes down to 3" inside the saw cabinet. That'll take some more thinking to fix.

[Chet]

The choke point is why  was thinking it would be good just to replace.  Maybe even temporally with something along these lines. Dust Hood 

Should be easy enough with a little aluminum duct tape to seal. 

[Bombarde16]

Yup. We're on the same page.

The internals of the saw are engineered like a job site saw, so there's a blade shroud and they brought a 3" line out of that. Eventually, the solution will be to let the interior of the saw be a cabinet and pull dust from the entire thing.  That'll require me to close off the bottom of the cabinet (totally open) and where the cabinet meets the table (leaks like a sieve). At that point, I'm pulling a full 4" line out of the bottom plus the 2" line above.

[Chet]

Oh, I mis-understood your first picture, I thought it was a cabinet saw.

[Ron Swanson Jr.]

I work in a woodworking supply store and all day long I try to help frustrated people put together simple fittings for a simple connection to their DC. It's astounding to me how quickly this becomes infuriating as even the simplest of runs end to requiring multiple adaptors and joints. I've long thought that a good engineer should be able to come up with some "one size fits all" DC hose, pipe and fittings.

A good example is Sawstop's first overhead dust collection system. The 2-1/4" line joins the 4" port on the saw cabinet at 90°. I'm no engineer but I know that flow and suction are greatly improved if this branches off in a smooth Y joint instead of a hard 90°. I ordered their floating overhead system because of the bad design of the first system and even there, you would think that they'd have a dedicated part to tie the smaller overhead hose into the 4" port on the cabinet, but they do not. That is up to you to put together. 

More and more it just seems like DC is a design afterthought, thrown in hastily and as cheaply as possible. Which is too bad because there's sheer joy to be had by working in a shop with effective and non hindering DC system on the larger dust producing machines. 

[drzaius]

I have the original SawStop guard/overhead collector & didn't like the factory system at all for a couple of reasons. Firstly, there is so much restriction in that long, narrow, U-shaped pipe that connects to the (badly designed) port adapter down below. Secondly, I can't stand how that same pipe would just generally be in the way, especially with a router table built into the extension wing.

Instead, I dropped a short 2.5" flex from an overhead duct & used a rubber reducer to connect to the guard. Dust collection is very good, I got nothing in the way above the table, and I'm not loosing any suction at the cabinet port.

[Chet]

32 minutes ago, applejackson said:

More and more it just seems like DC is a design afterthought, thrown in hastily and as cheaply as possible.

One would like to think that by this point in time there would be some standards that the DC industry worked with.  Why does a blast gate made by company "A" not fit into a fitting or flex hose also made by Company "A" with out having to buy an adapter from Company "B" because Company "A" doesn't make one. 

[Chestnut]

Please allow me to direct your ire at the proper people. It's not the engineers, they know better and if they had their way everything would work together perfectly. The accountants and the business managers want to maximize profit and force the engineers to cut their designers back to acceptable tolerances decided by the accounts and business people.  This isn't a bad thing because if engineers had their way everything would be 5X more expensive, though it'd never wear out and all the companies would go out of business.

We are capable of making roads that would never require construction again, or building bridges that will stand for millions of years. You just can't afford it.

Also that little bend probably does more to help the flow in the smaller pipe that you are giving it credit for. It is blocking off some area of the flow in the 4" pipe but because that is getting choked down later the restriction is inconsequential. What that "restriction" does though is create a small are of low pressure at the inlet to the main system to increase flow in the smaller pipe. The smaller pipe needs more pressure difference from one end to another to flow the same amount of air so they use stuff like this. I hate to say it but removing it is probably reducing performance.

I could probably explain things more thoroughly but fluid dynamics with a compressible fluid is complicated and I've only taken a few classes on it. It also doesn't follow as much common sense as people think it does.

Edited December 14, 2018 by Chestnut
Spelling

[Tpt life]

Some times...on the other hand I have worked with plenty of engineers who could not conceptualize how their designs conflicted with others’ designs. It is always helpful to have them tour the floor after construction attempts in prototypes.  Good old fashion tests on the machine help too. So, who had good success and so sold the machine that way?

[Gary Beasley]

I also wonder where the brains are to have the plastic blast gate flanges tapered so no amount of pressure from the hose clamp will hold the hose in place. At least mold a ridge aound it to trap the fitting in place!

[Chestnut]

3 minutes ago, Gary Beasley said:

I also wonder where the brains are to have the plastic blast gate flanges tapered so no amount of pressure from the hose clamp will hold the hose in place. At least mold a ridge aound it to trap the fitting in place!

That's a double edge sword because the gates are designed to fit inside hard pipe as well as flex pipe. Hard pipe won't flex around the ridge like flex pipe will. The taper is there so small differences in ID will still function with the gate. If your having issues some sheet metal screws and silicone will do the trick.

Everyone loves beating on the engineers but yet don't bother to get the education to work the job...... if you think you have what it takes to do our job better your more than welcome to sit the exams and take my place.

[Bombarde16]

2 hours ago, Chet said:

Oh, I mis-understood your first picture, I thought it was a cabinet saw.

Grizzly G0833P

http://www.grizzly.com/products/Grizzly-10-Hybrid-Table-Saw-with-Riving-Knife-Polar-Bear-Series/G0833P

[Gary Beasley]

Ive been accused by an engineering student of thinking like an engineer, So I could go there if I were 30 or 40 years younger. Looking at this particular brand I cant visualize it fitting hard pipe without an excessive amount of glue. Engineers for plastic drainpipe had this solved a long time ago.

[Ron Swanson Jr.]

1 hour ago, Chestnut said:

Please allow me to direct your ire at the proper people. It's not the engineers, they know better and if they had their way everything would work together perfectly. The accountants and the business managers want to maximize profit and force the engineers to cut their designers back to acceptable tolerances decided by the accounts and business people.  This isn't a bad thing because if engineers had their way everything would be 5X more expensive, though it'd never wear out and all the companies would go out of business.

We are capable of making roads that would never require construction again, or building bridges that will stand for millions of years. You just can't afford it.

 

@Chestnut yet again sir, I am impressed with your knowledge and that's an excellent point about engineering v. Accountants and marketing making design decisions and dictating policy.

[Chestnut]

11 minutes ago, applejackson said:

 

@Chestnut yet again sir, I am impressed with your knowledge and that's an excellent point about engineering v. Accountants and marketing making design decisions and dictating policy.

I don't want to make the accountants the enemy there really aren't bad people in this situation it's a balance depending on the budget they are shooting for. At the end of the day it's still the engineers job to make the product do what the marketing department promises and hit the budget.

[Ron Swanson Jr.]

@Chestnut true. True.

[wdwerker]

The romans built roads , bridges and aqueducts and some are still in service after hundreds of years. They didn't have computers or marketing departments but disappointing an Emperor was probably bad for your health . 

The lack of commonality in dust collection fittings is probably on purpose. Especially with vac attachments .They want you to buy their  overpriced tools, hoses etc. so they size them just enough bigger or smaller to make it difficult to use a competing brand. 

[Coop]

34 minutes ago, wdwerker said:

The romans built roads , bridges and aqueducts and some are still in service after hundreds of years. They didn't have computers or marketing departments but disappointing an Emperor was probably bad for your health . 

The lack of commonality in dust collection fittings is probably on purpose. Especially with vac attachments .They want you to buy their  overpriced tools, hoses etc. so they size them just enough bigger or smaller to make it difficult to use a competing brand. 

If bumpers on all vehicles were solid and at the same level, there would be less ER patients too. 

[Pwk5017]

Can you fit 4” hose inside the cabinet? I just modified the inside of a powermatic 72 to have an internal blade shroud, and 4” is tight. 4” on the inside of my KF700 is also a little tight. You really need to be mindful of the full bevel. 

[rodger.]

I run two different collectors for my sawstop. Then 4" cabinet port goes to my main DC, and the blade guard port goes to my Festool cleantex (I have the Bluetooth remote).

[wtnhighlander]

6 hours ago, Chestnut said:

 

Everyone loves beating on the engineers but yet don't bother to get the education to work the job...... if you think you have what it takes to do our job better your more than welcome to sit the exams and take my place.

'Nut, I admire you for getting that education, and using it.

But as someone that promoted from a maintenance tech to an 'engineering' position without the benefit of such education, let me offer an observation.

Every fresh-from-school engineer I have worked with in the last 30 years has come to the job full of knowledge, but all too frequently with the attitude that the knowledge they posses makes them right.

Not one of them understood the importance of compromise in good design practices. Compromise of function vs. cost. Compromise of durability vs. available material. Compromise of installation procedures vs. downtime availability. And one that irks me most, compromise of function & form vs. maintainability.

They seemed to be indoctrinated with the belief that 'proper' design produces a thing that meets (not exceeds) the functional specs provided with the least amount of effort, and little or no consideration to the poor shmucks that have to keep that thing working for decades.

I am glad to see you have some practical experience (aka, common sense) that tempers your theoretical education with a bit of reality.

Please forgive me for ranting about those that don't.

[Chestnut]

10 hours ago, wtnhighlander said:

'Nut, I admire you for getting that education, and using it.

But as someone that promoted from a maintenance tech to an 'engineering' position without the benefit of such education, let me offer an observation.

Every fresh-from-school engineer I have worked with in the last 30 years has come to the job full of knowledge, but all too frequently with the attitude that the knowledge they posses makes them right.

Not one of them understood the importance of compromise in good design practices. Compromise of function vs. cost. Compromise of durability vs. available material. Compromise of installation procedures vs. downtime availability. And one that irks me most, compromise of function & form vs. maintainability.

They seemed to be indoctrinated with the belief that 'proper' design produces a thing that meets (not exceeds) the functional specs provided with the least amount of effort, and little or no consideration to the poor shmucks that have to keep that thing working for decades.

I am glad to see you have some practical experience (aka, common sense) that tempers your theoretical education with a bit of reality.

Please forgive me for ranting about those that don't.

Crap this has taken too much of a tangent from the original point i wanted to make which was that port design might increase performance despite the contrary thoughts due to the fluid rushing around the obstruction creating a low pressure behind it both directing the dust from the smaller line and increasing flow....

I run into those people all the time also, but to unnecessarily beat down a group of individuals because of some young buck with an ego, isn't fair. Just like it isn't fair to take anyone and put them in a complicated situation where they have no experience and then berate them for not getting it right the first try. Your probably well aware of all the things that engineers need to know on a daily basis but the part that you may not know is that NONE of that stuff is taught to us in school. We get basically 4 intense years of advanced physics in college and then have to learn all the complexities and regulations in the field. All that stuff that you said is important is DEFIANTLY not covered in school. Maybe for an Industrial Engineer they cover some process design. All of that stuff is site/company specific how would a school even begin to teach that? There are how many different site and companies, the education would take half a lifetime. Schools don't tailor an engineer specifically to a company they don't even train them to a specific industry. They train people that will be able to get a job in 50 different states with thousands of different companies doing millions of different things.

I'm sorry that your company hires those engineers but they are the exception not the norm..... I know a LOT of engineers. It's also common to break the new guy's ego by throwing him in way over his head and letting him fail. Well i guess they just always throw you in way over your head and then make you figure it out...

I forgot the most important point the young engineer never creates the final design. In a good engineering department they have a senior engineer that should check everything before it goes to production. In the company i work for even the top engineers check eachother's work before it goes out. Nothing leaves the door without having at least 2 different sets of eyes on it or more. This may not happen everywhere but that's their liability.

[JohnG]

As an accountant, I must point out that the accountants are also not making the decisions. We just report the data that is requested and/or required. That data is handed off to other departments or parties, and they make their decisions based on a variety of factors, including but not limited to the data provided by the accountants. 

Accountants don’t set the budgets. They likely draft them based on prior data and forecast input from different departments, but they are modified and approved by CEO/President and heads of other departments. Accountants will provide reporting on budget vs. actual, but don’t decide what happens if the budget is exceeded. Even the Controller and CFO have less sway over the operations and decision making than people think.

The accounting/finance department may send message to other departments that they have to cut back or reduce spending, but that is sent on behalf of someone else.  The accounting department may tell another department that they are approaching or have exceeded their budget, but that other departments decides how to proceed, not the accountants.

There are many places where decision making can differ or break down, so it’s not even fair to blame the CEO or President for certain problems. Without knowing all the specifics for each situation, it is foolish to blame any one department or party. Companies are organized and operate in a wide variety of ways, and the answer in one situation is likely not the answer in others.

 

I fully agree that engineers usually get the bulk of the blame for any design, though they don’t have as much control over what they are designing as people think.