Dust collection problems

[Texas splinter]

I have a Delta Model 50-775 dust collector that I bought at Lowe's about 4 years ago. in my old (small) shop, it sat against the wall about 3 feet from the saw and jointer. When I moved into my new shop, I had it sitting next to the saw and jointer because I only had the short hose that had them connected in the old shop.
I got motivated a month or so ago and went out and bought 4" Drain/Waste tubing and fittings, moved the Dc over to the wall (about 8' from the saw) and then ran the tubing from the DC, up to about 8' high, then across to the saw, then down to a 4" Y fitting, splitting it to the saw and to the jointer. The jointer has a 4" port, so I just used the old 4" hose I had used before to connect it. For the saw, I dropped the tubing size down to 3" for about a 6" run, then installed a 3" Y fitting, reducing down to 2 inches for a hose to the BT310 and a 2" hose up to the Shark Guard.
It seemed to be working just fine but today, I disconnected the hose from the shark guard to suck up some sawdust on top of the saw and it wouldn't pick up the sawdust. I put my hand over the end and there was no suction.
I started disconnecting fittings and discovered that the whole lower part of the system, from where the 4" Y fitting splits to the jointer and saw to the jointer was full of jointer chips. Cleaned all that out and still don't have much suction. The rest of the lines seem to be clear. I need to remove the ducting from the inlet of the DC to check one more thing, the DC has a "trap" like in your sink to keep large items from foing down the drain. I once found a piece of insulation it had sucked up and it was blocking the line because it caught on that trap.
If that is clear, I'm wondering if going down to 3" tubing would increase the velocity enough to pull the jointer chips through the system.
Or, is the 1HP DC jsut too small for that much tubing?

[LCHIEN]

my guess is that 1 hp is maybe a bit small for a lot of tubing, sounds like 20 feet or more??? 16 of pipe and another 10 of hose?
Also necking down below 4" for smaller DCs really puts a serious restriction and you lose a bunch of head and consequently CFMs.

Check the inlet port of your DC, a lot of DC's have a screenlike device over the inlet to keep larger debris out of the impellor... with a lot of larger chips it can plug the screen and fill your hose.

of course the proper way to get more velocity is to get more CFMs by getting a bigger motor.
Are you using gates on the sides of the "Y"? If you are leaving both branches open then you will lose a lot of CFMs to the open, but unused branch. Once a side (e.g. your jointer) begins to plug up, then most CFMs end up going to the more open side.

[dbhost]

I don't see any mention there about blast gates...

IMHO, a 1HP DC is just too small to run remotely like that.. Splitting the 4" to 2 2.5" branches works, I've seen it, but going up, down, around through wyes, bends, and ribbed hose is just gonna kill your system...

Go back to the shorter hose run if you can, or at the very least try to get your bends minimized, and add some blast gates...

[Uncle Cracker]

You will not help by reducing the size of your ducting, because, although you may increase velocity in restricted runs, you will decrease overall suction strength upstream at your machinery. My 1.5 hp Delta works fine ducted at 4" all over my shop, but I still must use blast gates to isolate the machine I am using from the others, so if you don't have blast gates, you need to get them, and if you do have them, you may need to upsize your DC. Also, you can avoid overwhelming your system by using lighter cuts and more passes on the planer and jointer, as these can generate a choking quantity of chips in a hurry.

[eddy merckx]

If you really, really want to know what will work and you have some time, check out Bill Pentz's site. http://billpentz.com/woodworking/cyclone/index.cfm. Bring your coffee pot.

Eddy

[LarryG]

I need to remove the ducting from the inlet of the DC to check one more thing, the DC has a "trap" like in your sink to keep large items from foing down the drain.

I used to get a lot of clogs at this point while jointing. Two or three years ago I cut that trap-like grid out of my HF 2HP DC, and seem to recall a couple other members here doing likewise. Now and then a large chip or pin knot that the jointer or planer pulls loose will whack the impeller and make a lot of racket, but it doesn't seem to hurt anything and I've experienced no more clogs.

[ksum]

As mentioned, there was nothing about blast gates. If you don't have them, put them at your wye's, etc, so you can close off the run going to the jointer when using the saw, and vice-versa. If they are closer to the tools, move them. I also have one on my Shark Guard split so I can close it off when not needed. Closing down all unecessary pipe will greatly help in keeping the pipes clear.

Blast ggates are easy to make from scrap plywood and masonite, or get the plastic ones and cut the bottoms off so saw dust doesn't eventually clog in the bottom, keeping them from fully closing.

As has also been said, though, the unit may be too small for that much pipe. Minimize the pipe lengths as much as possible. Also, use 2 45 degree bends instead of 1 90 for better air flow. Last. minimize the flex pipe as much as possible. The rough interior inhibits airflow.

Karl

[smorris]

I have the same collector and there is an X shaped obstruction in the housing to block big things from going in. That never saved me from sucking up bags, gloves, etc but does block up with jointer shavings. I cut it out and never had a problem with it clogging up after that.

I do make it a point not to suck small animals, gloves, etc into the system anymore.

[dbhost]

Okay I am going to analyze this as best I can...

I have a Delta Model 50-775 dust collector that I bought at Lowe's about 4 years ago. in my old (small) shop, it sat against the wall about 3 feet from the saw and jointer.

Definately a SMALL Dust Collector. Not known to be a bad unit, but kind of smallish...

When I moved into my new shop, I had it sitting next to the saw and jointer because I only had the short hose that had them connected in the old shop.

Kind of how I have heard these will work fairly well, close to the unit in question...

I got motivated a month or so ago and went out and bought 4" Drain/Waste tubing and fittings, moved the Dc over to the wall (about 8' from the saw) and then ran the tubing from the DC, up to about 8' high, then across to the saw, then down to a 4" Y fitting,

Not horrid, not great. You are going UP which means pressure and CFM drop, but you are also going down, which means those should go back up a bit, not an equal trade though... With only 650CFM of your DC to start with, your suction will suffer.

Likewise you have to have at least 3 90 degree bends in there, probably 4 to make the turns you are talking about. NOT a good thing for air flow. IF you are going to use bends, make absolutely certain you are using long radius elbows so that you restrict air flow as little as possible... Likewise, each ribbed section of hose induces turbulence and therefore CFM and static pressure drops. Keep those runs as short as possible!

splitting it to the saw and to the jointer. The jointer has a 4" port, so I just used the old 4" hose I had used before to connect it.

No mention is made here at all of any sort of blast gate, this is a BAD thing... Put a blast gate at each side of the wye. Each side of the plumbing circuit must be run independently, that 650 CFM gets cut down REALLY fast, especially if you are allowing HUGE air leaks such as the open line to the saw when you are running the jointer etc...

For the saw, I dropped the tubing size down to 3" for about a 6" run, then installed a 3" Y fitting, reducing down to 2 inches for a hose to the BT310 and a 2" hose up to the Shark Guard.

Necking down to 3" is another CFM loss. Keep your run size at 4" until you come to a 4" wye just before the saw, then drop down with 2 4" to 2.5" reducers to your lines to the back of the saw and the shark guard...

Now...

I am no know it all by any means, and take my advice for what it is worth...

If it was me, I would go back to rolling the DC close to the tools in question, and on the saw, use a Wye, and the reducers like I had talked above. If you want to plumb a system, you will likely need a bigger motor / impeller, but I think you CAN do it with yours, in that case, keep your bends VERY gradual, keep ribs, bumps and other obstructions to a minimum. Keep your runs as short as you can on the tubing, and get rid of that screen thing. Also, add some sort of baffle, like the Thien baffle, or a neutral vane to that DC. I would not add a separate cyclone separator to that system as you cannot afford any CFM loss. Take lighter passes on the jointer too!

I'd suggest checking out Phil Thien's website, but it appears he is busy chaning out his forum software to PHPBB... No biggie, but it may be some time before he is back and fully up and running... His old forum had some great examples of DCs in that size range and smaller doing a great job for small shop plumbed applications...

[Texas splinter]

I neglected to mention the blast gates, but I have them. There is a 4" blast gate in each leg after the Y fitting and then a 2" blast gate where the hose to the shark guard hooks into the system.
After sleeping on the problem and looking at it again in the shop, I think my best plan is to create a "milling/sawing" station in the shop and put the DC in there, close to the machines (BT3100, bandsaw, jointer & SCMS) with the hose back on the ground. It is easier to put the wires in protectors and run them across the floor than to have that 4" hose running across the floor in the walkway.
So, it's back to graph paper and redesigning the floorplan.

[gsmittle]

If you really, really want to know what will work and you have some time, check out Bill Pentz's site. http://billpentz.com/woodworking/cyclone/index.cfm. Bring your coffee pot.

Eddy

And sit in a comfy chair!

g.

[JimD]

Chuck,

I also have a 1hp Delta DC. I have it hooked to several runs of 4 inch PVC, waste and drain, with home-made wooden blast gates at each tool. I sometimes run the gates on the BT3100 and my RAS/CMS station open at the same time but never successfully have the blast gate on my 8 5/8 jointer/planner open at the same time as any other tool. Even with the suction closed off to all the other tools, I still sometime plug that 4 inch pipe when using the jointer/planner and have to stop and clean it out. The hard pipe to the jointer is 6-8 feet and there is another 8 feet or so of flexible pipe. I think less flexible pipe would help but I am currently willing to put up with the occasional plugging rather than give up placement flexibility for the jointer.

A couple other things that might help. I have found my Delta plugged several time at the inlet the the DC. There is a metal rod coming across the opening that protects the fan from debris that will also collect things like pieces of fiberglass insulation as well as the large pieces it is supposed to stop. The planner seems to generate large enough pieces to stop mine up at this location.

The other thing I did that seemed to help was to go to an oversized felt bag that LOML did a little sewing on to make fit. I think we got it from Highland Hardware. At least at the time, they were one of a few places that sold individual bags. I put the oversized bag on the top and a regular bag later from the same source on the bottom. More filter area seems to get you a little more airflow. It is larger diameter but about the same height so we just reduced it where it joins the DC.

You did not mention the type of blast gates but I gave up on the plastic ones that I started with. They neither fully opened or fully closed. I find homemade wooden ones from plywood scraps to be significantly better (and a good use of scraps).

Jim