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Messages - BrianHood

#1
Air moves in such mysterious ways, there might be a gain in static pressure. Glider wings for example are kept as smooth as possible but at a certain point pretty far back along the wing zig-zag or dimple tape is added to create a little turbulence to help 'unstick' the laminar flow of air from the wing.

https://wingsandwheels.com/tapes-seals/turbulator-dimple-tape.html

And golf balls have dimples. So maybe some texture would be a benefit. On the other hand it seems like all the baffles work so well perhaps it's just fussing.
#2
From R2-
"If I were building another tophat I would stretch the aspect ratio slightly from my previous build"
First off I'm impressed you have been able to retire twice- I'm only up to retired 1/2.

As soon as I can find time in the project flow I'll build a top hat, probably this one. So, any thoughts you share are being studied carefully. One question I need to search through the forum for will be finding a bell mouth fitting. I have the exact same DC as you do. I'll do the straightener of course, I guess the cross blade or the three blade.

BradD
thanks for posting the file. I imported the .dfx file into Vectorworks, made a few mods, then exported to Fusion360, so now I have a 3D model. Super easy and I'm not even very good at software. I'll import that file into a Shaper Origin handheld CNC 'robot router' and zip it out of 1/2" ply.  Really appreciate you efforts and the file, I will post the SVG file here when I get it ready in case that's of use to anyone.
#3
Quote from: jgt1942 on March 30, 2017, 09:39:18 PM
Quote from: BrianHood on February 27, 2016, 07:10:41 PM
Completed a build which that turns on a DC whenever the machine(s) associated with it draws power, and senses when the DC barrel is full and kills power to the blower. The priorities for this project were reliability, low cost, and an easy build. Requires five components beyond common wiring materials and an enclosure for an all-in cost of ~$105 (lot of ebay). Build time was five hours (I'm kinda slow) not including rounding up the materials.

Uses a 2hp rated mercury filled relay for the blower, in which one conductor is wired to a metal cup of mercury and the other a probe that is dropped into the cup, eliminating noise, heat, and arcing. Extremely robust.

Thanks to this group for suggesting the Hawkeye current sensor and to a thread over at sawmill creek with the proximity sensor part numbers.
What are the part number or the link to the part numbers in the sawmill creek forum?

Banner S18P6D photoelectric sensor
#4
I own one of these which I connected to a Festool Sys-vac (with a tiny bag) and it works extremely well. As per usual, I end up with only the finest flour in the vac bag at a rate of about 2 oz for each 1/2 of a 5 gallon bucket.
As you can see from the photos posted by the OP, the inside of the top has a honeycomb texture and I wonder if this improves performance?
#5
Bernard,
I reacted to your phrase 'killer dust' because I suspect wood dust is nowhere near as bad as it is being made out to be, given reasonable precautions. However, it's just my opinion, and I'm open to changing it if the evidence appears. I agree with you that it's important to have a strategy to keep dust levels to a safe level, whatever that is. Because of a lack of standards and information it may be impossible to determine what that safe level is, so we each have to make our own decisions about what is safe what is not.
I found this study to be very interesting:
http://oem.bmj.com/content/early/2010/11/11/oem.2010.060004.short

From that study:
Abstract
We investigated whether a history of wood dust exposure through occupational and hobby-related activities was associated with increased lung cancer risk.

risk of lung cancer was examined in relation to employment in wood-related occupations, working with wood as a hobby, as well as cumulative wood dust exposure that took into account both occupational and hobby-related sources.

Results While we observed an increased risk of lung cancer associated with working in a sawmill (OR=1.5; 95% CI: 1.1, 2.1), we found no evidence of increased risks with other occupations, working with wood as a hobby or with estimated cumulative exposure to wood dust. Contrary to our hypothesis, we observed modest decreased risks with exposure to wood dust, although no dose-response relationship was apparent.

Another interesting read:
https://woodgears.ca/dust/dylos.html
If you read the article a point of reference is that in an ISO Class 8 clean room (the most dirty) a reading of 1,000 would be the highest allowable, and the author was getting lower readings in wood shop conditions using reasonable care.

I guess all we know is that opinions vary!
#6
Bernard,
thanks for the reply.
I personally don't think wood dust is very harmfull to all but a few people with some preexisting underlying issue, just never saw it be a problem in 40 years in the construction trades. I do remember a big problem when MDF first came out, we all noticed it and most reacted badly to it until better products came along. For awhile we wouldn't let that stuff in the shop and now that I only build what I want to, the way I want to, I don't go near it.
I got the Delta dust collector with the floppy bag, swapped to the Wynn, and I'll get the SDD pretty soon. I've just got to many other projects with deadlines or that I'm excited about to be building something I can buy for $170, but if that wasn't the case I build a Thein in a heartbeat.
I've read the entire Retired2 thread a couple times, pretty amazing.
#7
Thought this might be of some interest as it uses two different chambers to remove two sizes of dust (claimed). Certainly some interesting thinking went into it.

http://www.bridgecitytools.com/blog/2016/06/15/amazing-dust-collector-ever-heard/
#8
Thank you. I have your Delta dust collector without Thien baffle, have Wynn filter. Planning on a Super Dust Deputy as I have many projects to build, so no time to construct baffle.
#9
Thien Cyclone Separator Lid Discussion / Scrubbing
June 20, 2016, 04:41:33 PM
I'm concerned that all the swirling around I am seeing in the clear bag hanging down below the Wynn filter is evidence of scrubbing, and if I should do anything about it.

#10
I've had enough interest to buy another set of parts and will build a couple variations, draw up a schematic, etc. I am loving mine, after a couple years of walking across the shop it's like magic when it turns on by itself.
#11
A few more details:
A year ago JohnWho? suggested using a Hawkeye 800 current sensing relay to detect/control a DC. I can confirm that works very well.

A proximity sensor can be added to the control loop to a light or alarm when the DC barrel is full. I used a Banner S18P6D photoelectric sensor in a normally closed configuration- when it sees chips, it opens the control circuit, killing power to the DC. It was simpler than an alarm.

I choose to use a TORK TRP-D multi-voltage relay to provide the 24vdc required for the sensor, to detect the state of the Hawkeye, and to switch the high voltage to the contactor coil. The TRP is only rated for 1hp so a second relay was added.

An overide ON switch was added.

Any number of variations is possible, such as remote manual on/off using the TRP low voltage contacts, perhaps at the blast gates. Or just using the proximity sensor for barrel overfill.
#12
Completed a build which that turns on a DC whenever the machine(s) associated with it draws power, and senses when the DC barrel is full and kills power to the blower. The priorities for this project were reliability, low cost, and an easy build. Requires five components beyond common wiring materials and an enclosure for an all-in cost of ~$105 (lot of ebay). Build time was five hours (I'm kinda slow) not including rounding up the materials.

Uses a 2hp rated mercury filled relay for the blower, in which one conductor is wired to a metal cup of mercury and the other a probe that is dropped into the cup, eliminating noise, heat, and arcing. Extremely robust.

Thanks to this group for suggesting the Hawkeye current sensor and to a thread over at sawmill creek with the proximity sensor part numbers.



#13
R2
Thank you for the link, I had skimmed it, as I have so many of your posts (Your posts and the replys are an amazing source of ideas and inspirations) but was motivated to go back through them more carefully. There I saw the Hawkeye 800 CSR which I did not know about and just ordered ($6.75, eBay). I had considered and rejected CSR's but now I'll give it a try.

#14

I was thinking about ways to remote switch DC's and Vacs. I know this has been kicked around before but I was looking for a very low cost yet crisp execution.
Build #1, at the milling machine I have a vac in a cabinet next to the mill with the hose run out of it, the nozzle is often attached near the cutter with magnets and sucks the chips up as they are made, also quite useful for clean up. Being in the cabinet it is very quiet, but the on-off switch ends up in the cabinet so I've just been plugging and unplugging it-super lame.

Solution took .5 hour to build:
A TORK TRP-D self ballasted relay ($25 for 4 of them on Ebay) was threaded into an outdoor style box (had it laying around), phone wire was run to the LED illuminated switch ($7 from Zoro tools). Cord from box to wall, outlet installed in box, done.  TORK relay is rated 1HP 120v to 277v.  The LV wire can be run to blast gates and gates used as a switch. Relay supplies 24V if needed, in this case powers the red led when on.



Other ideas:
A 2HP version for my DC (+$35).
A version that senses 'wind' from the TS blade, such that the DC runs when the blade is spinning (+$12).
A wireless version (+$50 for the receiver and $25 for each remote switch).

Still trying to figure out a way to combine wireless and wind sensor.

I'm open to ideas and feedback on the concepts,

keep it clean,

Brian
#15
Thank you.
Full speed ahead.