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Wayne
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Discussion Starter #1
My lady wanted some birdhouses made, ( 5 ) from some fir she had in my shop. So being the nice guy I am, I proceeded to make them. I cut the fir in 3' lengths, and proceeded to plane it to a workable thickness. It didn't take long and my ducts were stopped up with P... shavings. OK, got that cleared out, restarted again and within a minute they were stopped up again. Finally said the Heck with this and just let the shavings go on the floor, swept them up after I was done.

My ducts are all 4" pvc and has never stopped up on me before. I still have to unclog the latest blockup, and hopefully no more p... will be planed in my shop.
 

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Thumb Nailer
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Never worked with fir, but assuming it behaves a lot like southern yellow pine... I have had no problems with my DC and planing / jointing SYP... How is your setup? Where is it stopping up at? Do you have a separator in the system somewhere?
 

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Wayne
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Discussion Starter #3
Never worked with fir, but assuming it behaves a lot like southern yellow pine... I have had no problems with my DC and planing / jointing SYP... How is your setup? Where is it stopping up at? Do you have a separator in the system somewhere?
My setup has 90º turns and one of them stopped up, twice. Dust collector is HF 1 1/2 HP, and has always been dependable. All ducts are 4" as I stated. It wasn't actually fir, but pine, which is in the fir family. I do have a separator. It just never got that far.
 

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My setup has 90º turns and one of them stopped up, twice. Dust collector is HF 1 1/2 HP, and has always been dependable. All ducts are 4" as I stated. It wasn't actually fir, but pine, which is in the fir family. I do have a separator. It just never got that far.
Can you eliminate the 90 degree elbows and replace each of them with (2) 45 degree elbows and a straight piece between them? This will allow for a better flow of material.

Jon
Northern Michigan
 

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Wayne
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Discussion Starter #6 (Edited)
I have given thoughts to replacing the 90's with 45's but as yet I have not got it done. This is the first time I have had any stoppages, so it hasn't been a priority. It may become one soon, but I still say no more pine in my shop. If more pine comes into my shop, it will be for the wood heater.. It burns good and heats well.
 

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I have given thoughts to replacing the 90's with 45's but as yet I have not got it done. This is the first time I have had any stoppages, so it hasn't been a priority. It may become one soon, but I still say no more pine in my shop. If more pine comes into my shop, it will be for the wood heater.. It burns good and heats well.

watch out for creosote build up from burning pine. I avoid it in my wood stove.

Jon
Northern Michigan
 

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You might want to read Bill Pentz' site in regards to ducting. The tighter the turn, the more it will make your air stream slow down. Generally speaking, 90 degree turns are bad news. Use a pair of 45 degree elbows, or if you can find them, long sweep 90s. Yes pine comes off in LONG strands from the planer. Then again in my experience so does oak. Pine however is pitchy, especially when green, and the shavings can, if they aren't moving fast enough, clump up. If your airflow isn't moving fast enough to keep the system from jamming while planing / jointing pine, odds are excellent you aren't pulling enough air through the system to get the fine particles you want to collect anyway.

My suggestions to fix this problem, and the problem that this points out which isn't really the pine are...

#1. Age / dry your pine / fir to insure no warping / twisting, and keep the stickiness of the pitch down. Mind you pine / fir does jam up blades and bits pretty good, keep those clean too!
#2. Minimize the best you can, any bends at all in the system. Make your runs as straight as physically possible.
#3. Eliminate any tight 90 bends, they kill DC system performance. Go with long sweep 90s, or a pair of 45s spaced by a couple of inches to help keep air speed up.
#4. Eliminate where you can, any corrugated flex hose. I will explain the last two in a minute...
#5. If you have a filter bag, give serious consideration, budget allowing of course, to replacing it with a 1 micron or better filtering pleated canister filter. You will have MUCH greater surface area for the DC to breathe through, which means the DC itself will breathe freer, elminiating restriction and flowing better.

Think about airflow, like cars on a road, to take a very tight 90 degree turn, or drive over a washboard road without totalling your car, you need to slow WAY down. The same is true with air. You want, as much as possible to reduce the restrictions in your air flow... To more or less keep those cars moving at as close to their maximum speed as possible.

I am curious, you mention a HF 1.5 HP DC. I am aware of a 1 HP model, the small portable single bagger, and a 2HP model, the upright with the ring and an upper and lower bag. When did they sell a 1.5 HP?

Due to the amount of pitch in pine, I would also recommend against burning it in a fireplace or wood stove. That pitch will build up in the chimney and become a fire hazard itself unless you keep that chimney clean all the time... Yes it burns fast, and hot, which is one of the things that makes pine scrap a great thing to take to the beach for bonfires, but again, the pitch makes it somewhat dangerous for indoor heating...
 

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P fir? Is that Pseudotsuga menziesii/Douglasfir? Not my choice to build anything.
SPF is the COFI generic term for lumber which could be spruce, or pine or fir (true fir = Abies sp.)
The birds don't measure birdhouse wall thickness. Door size matters.
 

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watch out for creosote build up from burning pine. I avoid it in my wood stove.

Jon
Northern Michigan
That's an old wives tale. Creosote is condensed wood gases. When you burn wood, volatile gases are released, if they cool too much before they leave the chimney, they condense on the inside surface of the chimney. The biggest culprit is burning wet wood with too high a moisture content. The water vapor produced robs heat from the flue gas. Depending on which stage of creosote you have it can be gummy, which might be why people associate it with pine and the pitch that goes along with it. My grandpa always said not to burn pine, but the combustion engineers i work with say otherwise.
 

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Wayne
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Discussion Starter #11
"If more pine comes into my shop, it will be for the wood heater.. It burns good and heats well."

I don't burn pine in my heater. I said if it came in my shop that is what it would be used for, and yes I know about the creosote buildup, but I keep a hot fire in that heater.

I will be making changes to my ducts, and get rid of the 90's and use the 45's ..
 
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