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Thread: vernacular built ergonomic correct workstation component help

  1. #1
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    vernacular built ergonomic correct workstation component help

    I do have two kinds of arthritis already, gave up my large bore pistol hobby years ago because my wrists hurt for too long after matches, that kind of thing.

    What I am looking at, already started prototyping, is vernacular built (like in Chris Schwarz' _The Anachist's Design Book) office furniture. It should be realtively cheap to make, and fit one person, the buyer or recipient - perfectly.

    The problem with mass produced office equipment is it is cheaply made, expensive to buy and doesn't actually fit anyone correctly. For my current corporate cubicle I started by buying a plastic floor mat, a chair mat, so I could roll my chair around without putting too much stress on my knees and ankles. Then I installed a $50 keyboard drawer to the bottom of my desk that probably cost $2.50 to make, it is junk. Then I had to adjust my desk height so the keyboard was at the right height relative to my body, then build a monitor stand to get the monitor at the right height. Thankfully I had to raise, rather than lower my desk top to adjust the final keyboard height.

    I get that a lot of folks who aren't recreational wood workers are stuck buying crappy adjustable stuff. We, registered user's here, can just make something that works perfectly for one person, and using vernacular techniques we(I) can make them inexpensively.

    The thing is, once someone hits 18, 20, 25 years old the growth plates in their bones are going to close up and that person will need their chair seat height and keyboard tray height and lumbar support height and armrest height and monitor height the same year after year after year until the discs in their spine start compressing. Which started about age 27 for me I guess. smiley.

    I am working on keyboard trays/ keyboard tables and I feel pretty good about it. Typically for most people who can buy clothes that fit off the rack, the tops of the keys on the keyboard should be 1-2 inches above the tops of the thighs. With a keyboard on the tray there isn't room left for 8/4 stock to be used as the tray surface, but Chris' staked work table ( chapter ten in the expanded edition as above) should fit the bill.

    I am starting with the tallest clinician in my department, the bottom of his patella is 22" above the floor anteriorly, his popiliteal pulse is 23" above the floor posteriorly, both measurements to the nearest quarter inch bilaterally. He is well over 6 feet, I think about 6' 5". I don't think he is tall enough for me to get away with using 2x8 or 2x10 contruction lumber for the table top, but I am going to try on the prototype. The other thing is going to be to locate the feet of the legs under the corners of the table at the mouse side, and then pull the feet back away from the end maybe 1-2 inches on the side without the mouse - that way if the overall width needs to be shortened to fit a new cubicle, there is a place to take some width from.

    I do like that this method allows me to build a nice table at an aesthically pleasing proportion, use it as a desk with a separate stand alone keyboard table at my perfect height, with a monitor stand on it, and then hand down the pleasing table to a grandchild or etcetera that they can use as a table, or make their own keyboard table and monitor stand and use it as a desk themselves, unbesmirched for handoff to the next generation.

    I got some questions about office chairs I don't expect to build one in 2021, just thinking ahead. The main thing that bugs me is called the "seat tilt" in Chris' book referenced above. When I internet search on "ergonomic workstation" I see the same skeleton over and over with different clothes on it. Ergonomicists call for an angle between the spine and femur of 90-120 degrees for an ergonomically correct workstation. So the seat is either level, or lower at the front that at the rear. Chris likes a seat angle the other way, a bit lower at the back than at the front for keyboarding. In text he states this helps his body slide back to reach the lumbar support. I note he is very skinny and likely quite tall, I think he said something like 6'2" in the workbench book when he was talking about bench height, but I am not going to go to my library to find the book and then look it up. I think he is tall and I know from youtube videos he doesn't eat enough BBQ pork.

    Does anyone own _Human Dimension and Interior Space_ by Julis Panero and Martin Zalnek? Is there anything in there about seat tilt? I would like to get those of my colleagues that want them set up with ergonomicaly correct tables for keyboarding and mousing, and build one for me and one for my wife (she is a bit under five feet) and get around to chair making before my current overpriced plastic monstrosity office chair wears out.

    Monitor stands are easy. If they are tall enough you can put cubby holes in the front. Use birdseye maple if you want.

    Looking forward to all y'all's input.

  2. #2
    For those like me who didn't recognize the term, here's a description of "vernacular furniture" LINK

    Im sorry that I can't help with your question Scott, but I'll look forward to reading what others say.
    Stay warm up there!
    Fred
    Last edited by Frederick Skelly; 11-11-2020 at 9:36 AM. Reason: Typo
    "All that is necessary for the triumph of evil is that good men do nothing."

    “If you want to know what a man's like, take a good look at how he treats his inferiors, not his equals.”

  3. #3
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    I am specifically looking at staked construction for the keyboard/mouse tables as explicated in Chris Schwarz' _Anarchist Design_. The three stools Derek Cohen just built look like the same method to me from the pictures.

  4. #4
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    Search Pinterest for "Jeweler's bench".

    They follow compact layouts as you describe.

    Consider a mockup with cardboard and wrapping paper tubes.

    http://imgur.com/gallery/8OQd08w

  5. #5
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    Scott, on higher end office chairs, tilt is accomplished in several ways. First, the back of the seat can be adjusted backward and forward to provide the 90-120 degree angles you mentioned. Second, the entire chair can tilt (think rocking). And third, the seat can be tilted forward so the front is lower than the back. I have never had an ergonomist recommend the front higher than the back unless the back is tilted back to maintain at least 90 degrees.

    Tilting the front of the chair down (sort of like the old kneeling chairs), reduces pressure on legs/thighs, while maintaining proper posture. Keep in mind, that the body likes to move to help with blood circulation. I would advise that the chair you build allows the user to change position over the course of a day. Sitting in any one position for long periods of time is not recommended.

  6. #6
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    Quote Originally Posted by Phil Mueller View Post
    Scott, on higher end office chairs, tilt is accomplished in several ways. First, the back of the seat can be adjusted backward and forward to provide the 90-120 degree angles you mentioned. Second, the entire chair can tilt (think rocking). And third, the seat can be tilted forward so the front is lower than the back. I have never had an ergonomist recommend the front higher than the back unless the back is tilted back to maintain at least 90 degrees.

    Tilting the front of the chair down (sort of like the old kneeling chairs), reduces pressure on legs/thighs, while maintaining proper posture. Keep in mind, that the body likes to move to help with blood circulation. I would advise that the chair you build allows the user to change position over the course of a day. Sitting in any one position for long periods of time is not recommended.
    I agree with all of the above. At one unit where I used to work we shared 4 computers among 12 clinicians. After a few months I could pretty much tell who used the chair I just sat down in last. In general I find skinnier and skinnier folks want the front of the chair higher and higher and eventually sloped towards the chair back. The converse is also true.

    Moving around regularly, getting up from the computer at least 5 minutes every hour, there are lots of things to do besides sit at a perfect work station to minimize repetitive stress injuries.

    After I get my basketball player set up - tall and skinny, I am going to look at a colleague who wrestled NCAA D2 in college. No fat on him, but he is BIG. I may have to put him in a kneeling chair to get him a correct keyboard height, his thighs are just massive. Have a tracking number on the LN honing guide to keep my tapered tenon cutter in business, and chasing two wood lathes on craigslist.

  7. #7
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    Rolling in my free time. I did score a lathe, with a duplicator on it over the weekend, so I should be able to crank out round tapered legs - after a massive re-organization of all my shop and home office scape. The lathe is six feet long assembled. Glad to have it, have to digest it.

    My thesis statement remains that once an individual is fully grown, the growth plates in their long bones are sealed shut, they have one perfect chair height and one perfect keyboard/mouse height and one perfect monitor height - until the intervetebral discs inbetween the bones of their spinal cord start compressing with age. Or they get a new monitor.

    Some folks will want a lower seat surface so they can put a cushion on it. That preference does not change their ideal seat height, just the height of the wooden surface.

    I agree moving to an ergonomically correct setup is uncomfortable for a few weeks, I have done it, the point is a correct setup does not cause more pain later.

    All of my colleagues are on office chairs with a gas piston for height adjustment. For now they can maintain a comfortable seat height, but those gas pistons don't last forever. 2 of my 14 colleagues have their keyboard height at a reasonable spot.

    After figuring out how to fit the new lathe into my shop tonight, I went looking on youtube for useful stuff.

    I have selected four videos I find useful for one reason or another, each three to five minutes.

    1. Published by the Wall Street Journal (I know, I know) but they interviewed someone who knows what he is doing, and the camera work allows the viewer to see the angle between the femur and the spine, to see the feet flat on the floor.

    https://www.youtube.com/watch?v=F8_ME4VwTiw

    2. A pair of Physical Therapists (DPTs actually -Doctorate in Physical Therapy) from Pittsburg, again with the camera work you can see what they are talking about.
    https://www.youtube.com/watch?v=VtauWcADpbk

    3. Mayo Clinic. The photography in this one does not let you see the long bones on camera, but the dude from Mayo Clinic (I have found Mayo to be a credible source throughout my carreer) is saying the same stuff, just not showing it well on camera. It doesn't increase your knowledge if you have watched the first two, but it will hopefully give credibility to the what the first two were able to show.
    https://www.youtube.com/watch?v=K88q_oEwRS8

    4. Another physical therapist. Again, excellent on camera demonstration of joint angles, with even more about the wrist and carpal tunnel area. I am confident the adjustable keyboard tray in his video has a short warranty.
    https://www.youtube.com/watch?v=mj6T...euHITKL0_wOuxl

    We can do better than this. I am convinced I am one of the least talented, least skilled woodworkers on this forum; and I can do better than this. I hang out here becasue I want to get better. The best way to get getter at a thing is to be around people who are better at the thing. You guys should be able to do amazing stuff in this area. My tallest colleague is 6'5", about 195cm. My wife is 4'10", about 147cm. There is no good reason to sit them down at identical desks and give them disposable plastic ergonomic bits to use briefly and consign to landfills.

    I can build individually ergonomically correct mouse/keyboard tables for anyone, relatively cheaply, using the staked table technique in Chris Schwarz' book. I will have to take on chairs next. With the correct chair and keyboard height anyone, within reason, can use any old table as a desk with a stack of phone books - oh right - a stack of amazon boxes as a monitor stand and not have repetitive stress injuries down the road.

    I will get back to shop re-org so I can get the lathe online. Got neck, shoulder, elbow or wrist pain since you have been working from home?

  8. #8
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    First prototype suite is completed, hopefully my last build at 1:8 scale, the math sucked.

    What I have here is the staked sawbench from _The Anarchist Design Book_ (expanded edition), only lifted to 24 scale inches, and the top stretched to 8x40 scale inches to comfortably accomodate a keyboard and mouse. The "desk" is the the worktable, chapter ten, with the top blown out to 30 x 50 scale inches at 30 scale inches height, and the staked chair (chapter 17) with a seat height at 17 scale inches and flat. The laptop stand on the table top is just a thing I drew, drilled and glued with a sight line at 45 degrees and a 15 degree resultant angle. The laptop (envelope scrap) has a screen size of 9x16 scale inches.

    The chair, I know, I know, looks like a dog's breakfast, does not have a crest rail and does not have armrests. I am done building doll house furniture and will do future prototyping at larger scale. I used bamboo BBQ skewers for the leg, 0.121 acutal, "one inch diameter" at scale. The plywood is close to .250", a bit under, essentially 8/4 stock planed flat at scale. Glad to screw up my first chair with leftover BBQ utensils and a plywood scrap.

    Over the next few days I am just going to look at the leg angles on the three tables and decide what needs to be tweaked. I have decided to not bother trying to make the angles of the chair legs 'work' with the angles of the table legs. I just don't have the brain power for that. I am going to have to figure out tapered octagon legs. I will have to do a little trig to get the feet just under the corners of the various tables, but I was awake for trigonometry and have google and have a sci calculator resident in my phone. I have noticed the legs "look" a little tapered in the pictures even though they aren't tapered in reality.

    I still think someone who has inherited Great Aunt Bessie's whatever table should be able to knock out a laptop stand, keyboarding table and chair at ergonomically correct heights for not a lot of money, break even point should be two-three years based on current big box store office furniture.

    Next up for me is a full scale keyboard/ mouse table, only not full length. I will do the eight inch width and the 24ish inch height, and locate the feet under the corners with math; but I am going to put it upside down in the room with the woodstove to warm and dry my winter boots over night. Also I have an idea for an adjustable lumbar support for the chair that will have to be executed full scale as a reality check.

    20201205_230416[1].jpg

    EDIT: All the rest of the offsets and angles I used are straight out of the book. Since I fiddled with the heights the feet aren't in right relationship with the corners of the tables. With this prototype I am just looking at angles, but am not expecting big impressive changes when I scootch the legs over a smidge to tuck the feet in. Once I settle on angles. My first impression is the two larger tables look fine together but I may need to fool with the smallest one a bit, maybe smaller diameter legs.
    Last edited by Scott Winners; 12-06-2020 at 3:48 AM.

  9. #9
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    Quote Originally Posted by Scott Winners View Post
    ... Glad to screw up my first chair with leftover BBQ utensils and a plywood scrap. ...
    I'd have clicked "like" for just this sentence!

    I don't really have anything to offer, but I'll be following your project because melding new concepts with traditional construction is intriguing.

  10. #10
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    Five weeks. It took five weeks to get my new lathe and duplicator integrated into my shop and a bit of practice with the lathe. Turning was my favorite part of shop class in junior high, getting stuffed into garbage cans being my least favorite. Once I felt up to speed, I turned these four legs this afternoon, and drilled tapered mortises into a scrap of 2x10, and reverse seared a tritip that came out really well.

    The prototype item (top nominal 9x10 inches) will end up as a laptop stand at my home office. It needs a new top, flat, and a new top, bigger, but the legs are ready and 2-3 inches too long. I used a 45 degree sight line and a 15 degree resultant angle, but the 2x10 scrap is badly cupped and slightly twisted; one leg is 5/8 shorter than the other three. I don't remember the major diameter (it's about 1.40 inches), the minor diameters are both 5/8 inches were the legs about 26" long.

    The good news is the pattern I made for my duplicator is a good fit with the tapered tenon cutter from Lee Valley. The bad news I will have to fabricate a clamp box to glue up a flat top.

    Pic one is my laptop stand, looks like it has a drinking problem because of the cup and twist, but it is standing.

    Pic two is four legs, one each in ash, hickory, hard maple and white oak. Ash is easiest to turn, but useless in my BBQ pits. Maple is a bugger to turn smoothly and of limited utility in my pits. I have hickory coming out my ears but it is second easiest to work. White Oak both I and my wife adore on beef, chicken and fish, and though worse than hickory to turn it is easier than maple to get a nice finish, so I will be shopping for white oak first and hickory second for future legs.



    20201220_183337[1].jpg20201220_183922[1].jpg

  11. #11
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    First product ships tomorrow. It is meant to be a laptop stand, to bring the monitor on the laptop up to ergonomically correct level so the user doesn't get a shoulder ache from reaching up to type, or a low back ache from leaning forward to see. User does need an accessory keyboard.

    One pic on the kitchen counter with all three coats of soap finish (first, last and only) drying out, and one with my laptop on it at the kitchen table. This one is 13" tall, and the legs stick out a little bit from the corners. At 5'10" personally I need nine inches of lift for the laptop in the picture to be the right height on my regular desk, but the recipient is 6'5" tall, and he has a different model laptop. I left the item tall so I can trim it a bit shorter (hopefully) and spend a little more time on the feet before final delivery.

    Design pointers welcome, encouraged, sought. Nine clinicians total in my office and I want to get these deployed, and nine keyboard tables; and after I learn to make chairs, nine chairs too.

    I do agree tapered ocatagon legs look good on staked furniture like this, but my immediate need is to prevent repetitive stress injuries in my colleagues, we have all been working too many pandemic hours.

    The one thing I can do without re-tooling is ream the tapered hole in the top bigger, so the major diameter of the leg gets tucked closer under the top, and carry the current taper further down the leg using longer stock.

    From there I could fairly easily make a different pattern for the duplicator on my lathe if the finished piece looks really bad to your eye...octagons ain't happening until my team is safe from repetitive stress injury.

    The syringe on the countertop is for injecting custard into homemade donuts. Just noticed it, sorry, not a drug user.
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