Today I Learned

  • Thread starter Thread starter Greg Bernhardt
  • Start date Start date
Click For Summary
SUMMARY

This discussion revolves around the concept of daily learning, where participants share various facts and insights they have recently discovered. Key topics include the woodworking technique "oyster veneering," the mathematical fact that 23! equals 25,852,016,738,884,976,640,000, and the medical terms "hyperacusis" and "diplacusis." Participants also touch on humorous observations about life, such as the impact of television on weight and the emotional sensitivity of Barn Owls.

PREREQUISITES
  • Understanding of basic mathematical concepts, specifically factorials.
  • Familiarity with woodworking techniques, particularly historical methods like oyster veneering.
  • Knowledge of medical terminology related to hearing, such as hyperacusis and diplacusis.
  • Awareness of cultural references, including the significance of historical events and figures like Muhammad Ali.
NEXT STEPS
  • Research the historical context and revival of oyster veneering in woodworking.
  • Explore advanced mathematical concepts related to factorials and their applications.
  • Investigate the medical conditions hyperacusis and diplacusis, including their causes and treatments.
  • Learn about the emotional behaviors of animals, particularly Barn Owls and their sensitivity.
USEFUL FOR

This discussion is beneficial for woodworking enthusiasts, mathematicians, medical professionals, and animal behaviorists, as well as anyone interested in the quirky facts of daily life.

  • #721
Bystander said:
Steel.
Nah. The teeth are spaced too far apart. That's a radial arm saw for cutting flooring or crown molding accurately.
 
Physics news on Phys.org
  • #722
Borg said:
spaced too far apart
Oops --- need new glasses.
Borg said:
radial arm chop
... and, so do you. I just looked at the configuration and "saw" an abrasive cut-off blade.
 
  • #723
Borg said:
Nah. The teeth are spaced too far apart. That's a radial arm saw for cutting flooring or crown molding accurately.
It's a chop saw, not a radial arm saw. In a chop saw the blade/motor pivots up and down. In a radial arm saw the blade/motor runs forward and back in a track

The blades are interchangable. The blade shown would not be good for steel, but they make abrasive disks that work on steel. The blade shown actually looks very much like one I once used to cut aluminum tubing.
 
  • #724
My bad. Yes, there is no arm to it. I have one like it and always refer to it (incorrectly) that way.
 
  • #725
... and today we all learned that people throw tools away rather than take the two minutes to clean brushes on a motor. Thanks, Jim.
 
Reply
  • Like
Likes   Reactions: jim hardy
  • #726
Yes it's a chop saw. Was sans blade but the residue on it was metal not wood. With a new abrasive cutoff blade for metal It throws a stream of sparks about 12 feet behind but the deflector directs them slightly downward. Looks like Buck Rogers' rocket engine.
It labors a bit on 1/4 inch steel plate but with the toothed blade shown in that picture (from their catalog) it would cut wood like a woodchuck.

I think it's part of my autism i can't stand to see good machinery wasted . A lot of aluminum boats go through the scrap yard, and I've rescued several antique outboards.
I'm learning how to wire washing machine motors for workshop applications, how else can you get a 1/2 hp electric motor for under 5 bucks ? Whirlpools are easy now.

Does PF need a "handyman's corner " ? I'm sensitive about PF's image, don't want to lower the academic standards with my play.
 
Last edited:
Reply
  • Like
Likes   Reactions: OmCheeto
  • #727
I find the rescue things are repeated quite a lot too, which makes me think like things being rescued are dumb or disrespectful or without any sincere gratitude.
What a practical "rescue" it does sound!
 
  • #728
jim hardy said:
Does PF need a "handyman's corner " ?
Sounds like a great idea --- post it in Feedback, and I'll second it.
 
Reply
  • Like
Likes   Reactions: OmCheeto
  • #729
zoobyshoe said:
The blade shown would not be good for steel...
That's probably true, however, a company named Scotchman Industries makes a http://www.scotchman.com/cold-saws/ that does have metal cutting teeth...

My wife is from Philip, South Dakota, so while there visiting in-laws ... I went through the plant.....:oldcool:

The company is primarily known for a product called the Scotchman Ironworker, which we used way back in welding school... that be, waaaay back.... lol

Here's the 350 cold saw in operation...

Their YouTube channel...

They very definitely make good products... although, a tad on the $$$ side.
 
Reply
  • Like
Likes   Reactions: OmCheeto
  • #730
Silicon Waffle said:
What is that used to cut ?

Red tape.
 
Reply
  • Like
Likes   Reactions: Silicon Waffle
  • #731
OCR said:
That's probably true, however, a company named Scotchman Industries makes a http://www.scotchman.com/cold-saws/ that does have metal cutting teeth...

My wife is from Philip, South Dakota, so while there visiting in-laws ... I went through the plant.....:oldcool:

The company is primarily known for a product called the Scotchman Ironworker, which we used way back in welding school... that be, waaaay back.... lol

Here's the 350 cold saw in operation...

Their YouTube channel...

They very definitely make good products... although, a tad on the $$$ side.
If you notice that saw can cut steel because it can do very low RPMs. Any blade with carbide teeth can cut steel in principle, but the average chop saw is set at a fixed RPM that is just too high: the teeth would burn up very quickly.

Any material harder than steel can be fashioned into a blade that will cut soft(unhardened) steel. In fact, hardened steel will cut soft steel, which is the situation with your average hack saw. The other variable besides relative hardness is heat removal. When a blade heats up too much it loses its hardness and will become dull. You have to either saw slowly to let the heat dissipate, or use a coolant.
 
  • #732
zoobyshoe said:
If you notice that saw can cut steel because it can do very low RPMs.
Well yes, I did notice, in fact I noticed when I went through the plant and saw one they used as a demo...

Also, I noticed...
For ferrous material, this unique type of cutting turns the blade at a very low RPM, similar to a milling process, giving a FAST, precise, burr-free cut without heat or sparks.
http://www.scotchman.com/cold-saws/

I'm not quite following ... are you agreeing, or arguing ?

Anyway... carry on.
 
  • #733
OCR said:
I'm not quite following ... are you agreeing, or arguing ?
I'm explicating why the saw you linked to can cut steel with a toothed blade while a "normal" chop saw couldn't.
 
  • #734
  • #735
zoobyshoe said:
I'm explicating why...
I see, so... you saw a saw, saw, that could out saw any saw you ever saw, saw... so, if ever you see a saw out

saw that saw you saw, saw... I'd like to see that saw, you saw, saw, saw too, see ?......:oldbiggrin:
 
Last edited:
  • #736
  • #737
obviously using dark net proxies,
 
  • #739
TIL: How to animate my stepwise (and incomplete) model of the solar system!
 
  • #741
http://news.yahoo.com/far-below-south-dakota-cave-holds-pure-promising-184902493.html
WIND CAVE NATIONAL PARK, S.D. (AP) — Hundreds of feet beneath the Black Hills, a team of scientists and researchers snake through dark, narrow and silent corridors of ancient rock to reach their goal: what is thought to be some of the purest water on Earth.
 
Last edited by a moderator:
  • #743
Today I learned that Wy'east is the native name of our local, tallest mountain, Mt. Hood.
I always thought it was just a clever name for a Western beer YEAST producer.
Coincidentally, Wy'east yeast labs overlooks Wy'east, the mountain, from the town of Hood River, which was named after the river, Hood River, which was named after Mt. Hood.
How Mt. Hood got its name according to wiki: "Lt. Broughton named the mountain after Lord (Samuel) Hood, a British Admiral at the Battle of the Chesapeake."
Ha! Hood Canal, in Washington state, was also named after the Admiral. I was housed at the submarine base in Bangor, on the Hood canal, for 3 years, while in the Navy.
Admiral Hood served in the Royal Navy for 53 years, and lived to be 91.

ps. I looked this all up today, when I heard that yesterday, the name of Mt. McKinley had been officially changed to Denali.
Looks like that took a while.
wiki said:
...
The Alaska Board of Geographic Names changed the name of the mountain to Denali in 1975 which is how it is called locally.
...
Congressman Bob Gibbs, who described Obama's action as "constitutional overreach" because he said an act of Congress is required to rename the mountain. The Alaska Dispatch News reported that the Secretary of the Interior has authority under federal law to change geographic names when the Board of Geographic Names does not act on a naming request within a "reasonable" period of time. Jewell told the ADN that "I think any of us would think that 40 years is an unreasonable amount of time."
 
  • #744
Today, I learned that it is possible to make sense by not making sense.
 
Reply
  • Like
Likes   Reactions: Silicon Waffle
  • #745
Reply
  • Like
Likes   Reactions: jim hardy
  • #746
It is really effective against insects, however.Edit: Today I learned how automatic subtitles work. I saw this video and didn't understand the speaker. The video has subtitles, but apparently google didn't understand the speaker either because the subtitles do not make sense at all (some of them are funny).
 
Last edited:
  • #747
Astronuc said:
TIL, "The DEET within insect repellant is an oily liquid known as diethyltoluamide that mosquitos and other inspects intensely dislike. DEET has been known to destroy the varnish on wooden tables, melt plastics, and even permanently mark TV screens."
https://www.yahoo.com/autos/how-something-you-spray-on-your-kids-can-melt-your-128334848277.html

Don't spray around furniture or cars, or probably anything else of value.
I recall how a can of repellant with DEET as its active constituent carried a note to the user along the lines of, "Caution: this product may be harmful if used for prolonged periods". Yet it gave no indication of what length of exposure might fall into the category of "a prolonged period".

Hours, days, weeks, or maybe months? Clearly, their legal department wasn't about to commit themselves on this score!
 
  • #749
I learned that many imports come from other countries.
[was watching old stand ups by Robin Williams, one of my favourite jokes of his he makes about George W Bush ]
 

Similar threads

What Did You Learn Today? A Tradition of Daily Learning and Sharing
  • · Replies 26 ·
Replies
26
Views
6K
Understanding the divide white/black/blue
  • · Replies 161 ·
6
Replies
161
Views
14K
Studying I feel I have lost it. How do I be dissolved in studies again?
  • · Replies 4 ·
Replies
4
Views
2K
Fighting for Financial Relief: Surviving COVID Debt
  • · Replies 9 ·
Replies
9
Views
2K
MHB Effective learning techniques for abstract mathematics?
  • · Replies 3 ·
Replies
3
Views
3K
Things that you regret not continuing to practice?
  • · Replies 14 ·
Replies
14
Views
2K
Learn to Play Piano - Tips for Beginners
  • · Replies 27 ·
Replies
27
Views
6K
I would love to hear about how you study math books
  • · Replies 5 ·
Replies
5
Views
2K
New realizations or "what I think I learned today"
  • · Replies 3 ·
Replies
3
Views
2K
Admissions How Can I Enhance My Statement of Purpose for a PhD Program?
  • · Replies 5 ·
Replies
5
Views
4K