Thread: Conundrum Curiosity Complex.

To completely construct something truly MacGyver'ed would be pretty awesome, although you will probably peev off the lady with random bits of stuff stored floor to ceiling!

Just a memory that this thread brought back to me...
When I was about 8 years old...building one of my first model airplanes (it was a TWA airliner), I was playing with the glue (the good Testers stuff in the red tube), squeezed into my hands and bringing them together then apart over and over made it stringy. And Believing I invented a new kind of string. Thanks for the memories.

Originally Posted by JimBC

Just a memory that this thread brought back to me...
When I was about 8 years old...building one of my first model airplanes (it was a TWA airliner), I was playing with the glue (the good Testers stuff in the red tube), squeezed into my hands and bringing them together then apart over and over made it stringy. And Believing I invented a new kind of string. Thanks for the memories.

Happy to oblige, kind sir.

First of all, thanks again to criswilson10 for taking the time to get caught up on, & responding to this thread. Which brings me to my next point...

I got a response from a fellow over at Freud Tools (Diablo brand parent company). He started with "Interesting idea..." and gave me some useful information, sprinkled between warnings of "serious injury or death". Lol. I'm not naive to the risks involved with this endeavor . Otherwise, I wouldn't have included that line in my e-mail about waving "...any and all liability..." for their company. IMO, nobody willing to pursue such an undertaking should be able to hold anyone responsible for the outcome, other than themselves!

Any-who... I think I will include a link to this thread in my response. It would greatly reduce the length of the correspondence, not to mention the amount of stuff I'd have to retype! I think it would improve his understanding of, if nothing else, the amount of thought I tend to put into these... "intellectual exercises" .

Any objections to me linking over??

Can't really see why not...

Might convert another gentlemen to the fold!

Message of response sent. I linked this thread. I explained a few things more about the concept in question.

In his initial response to me, he mentioned that the larger a circular saw blade is, the lower the RPMs required for it to achieve proper tensioning, thus allowing the blade to "run true". This is also well below the normal operating speed of any electric saw, so not considered worth publishing for public consumption. Lol, I get that. This isn't exactly a "normal" project lol.

So, with a 10" blade, proper blade tension is around 3,00-3,400 RPMs. He also provided a document (seemed to be part of a brochure, but more technical in nature) with "maximum safe speed" broken down by saw diameter.

I hope he finds the time to look over this thread, as it would have been a very long correspondence. You guys have helped me pour over, and get out of my head into a form I can review! Thanks.

A bit more back & forth with the gent at Freud Tools.

I sent:

If I am understanding you (and the document) correctly, I should be alright (operationally) within a range of 3,000 to 7,000 RPMs (with a 10" blade)? Am I correct, that larger blades have a more forgiving range?

Thank you very much for your timely response! I am not naive to the risks involved with this endeavor, though I appreciate the words of caution. My day job is not overly taxing on my mental faculties. Combine that with mild-to-moderate A.D.D., and I usually have an unrelated train of thought "on the backburner", so to speak. What I'm trying to say is this: this idea is not something slapped together on a whim, with a box or rust.

To be fair, I failed to mention that the idea has evolved into more of a human/bicycle powered sawmill. That, I feel, may be a more appropriate description. It started as having the need for a table saw, and evolved as more thought was put into it, trying to approach the idea from all angles.

I will have extra layers of precautions in place for at least the first few uses of this machine, once it is built. Like sheets of plywood as shielding against possible flying debris. I am also likely to position the bicycle "off center" from the saw blade, since I will be using multiple pulleys anyway.

In order to reduce the chances of your eyes glazing over, due to a long winded response in my part, I will refer you to a thread that I've started on a forum for wet shaving enthusiasts. On a related note: I shave with a straight razor, among other reasons, because of my fondness for precision.

Hmmm... starting to feel "long winded". I do hope you will give the thread a look, as it explains in much more detail the design considerations I've made.

http://straightrazorpalace.com/works...y-complex.html

If I recall correctly, pages 1, 2, 4, & 5 have the most to do with this concept.

To which he responded:

Unfortunately I cannot access external links. I did some research and the power you can produce is using a bicycle type device is about 100 to 150 watts. This is nowhere near what you need for even a bench top table saw. You would need 10 people on bicycles to produce enough power regardless of the gearing you used. Also every gearing system (pulleys, gears…..) actually consume energy as well.

And what I sent back in the wee hours this morning:

Dear Jim,

Ah, yes, corporate I.T. network security 101: do not trust/access outside sources/links/networks. Sorry, I'd forgotten about that.

Though it is true that I had not looked into how much energy/power output I am capable of, I have been doing quite a bit of research on "pedal power" as a means to drive equipment. I will spare you the history lesson. The technology has (in one form or another) been used for this sort of thing since long before electricity & internal combustion engines. I know how many RPMs my bicycle would produce at the wheel, at what I consider a sustainable pace on level terrain with light headwinds: roughly 250 RPM. With multiple sets of pulleys, I hope to obtain a rate of over 5,000 RPMs at the blade.

I am aware of the inherent energy loss that comes with any mechanical system. The blade, as well as the bearings used on this with undoubtedly require strict consideration, in order to ensure the best possible chance of success. If necessary, I will remove a "step" at a time, if it means increased RPMs at the blade. But, I believe the multiple pulleys would provide a similar property of energy storage as a proper flywheel.

As for the workpiece, I have a concept for bracing members to hold it down while a "mule" winches the wood to be cut across the table. The mule will be driven off the first step (shaft) in the drive train after the bike wheel. Obviously, the mule will be "geared down" to pull the workpiece at a VERY slow pace. The emphasis should be on a good operating speed for the blade, not to get the piece cut as quickly as possible. I'm still working on the particulars of the mule. The trick, if on the same drive, will be to slow it down enough. I will be rigging some sort of clutch, so the mule isn't explicitly always "on" when the blade is spinning.

This may seem like a lot of effort, even before stepping on the pedals. These intellectual exercises have become a fun hobby of their own! You have helped me with the question(s) I came to you with, and I thank you very much for your assistance!! If you would like to be kept in the loop on this whackadoodle project of mine, just let me know! I've been keeping my thread over at Straight Razor Place updated with the progress, so it wouldn't be much additional effort to (mostly) paste my write-ups into an e-mail for you.

Thanks again for indulging my curiosity!
Kind regards,
Chris R.

I was in bed shortly thereafter. Some time after getting to work today, after I'd had time to become fully conscious, a thought occurred to me... what if he assumes I'm attempting to produce electricity to run a DC motor, with a bicycle generator or something?? Maybe that is why, in his first e-mail responding to my question, he says:

Have you calculated if you can produce a constant output of about 1500 watts of power under load.

?

I think I will wait for a response (or until Tuesday evening at the latest) before I send off another e-mail wherein I jump to conclusions about his thought process.

Speaking of e-mails... with anything I type up, I always read through it several times before sending/posting. So when I see a typo of any kind, like in my response to him, I cringe. To this day, a thread I started has a missing period "." that haunts me!!! Pretty sure the new sentence had proper capitalization on the first word. But the punctuation M.I.A. drives me nuts when I post in that thread again !! /end rant.

Either way, I will continue to peck away at this project until I can at least prove to myself whether or not it will work. IMO, if this were Myth Busters, they would hypothesize (pre-experiment) that it is "plausible". But then again, I may just be a "silver linings" kind of kook!

Your metal disks are punch outs from electrical junction boxes. They are a mild steel and non magnetic.

Hah, junction boxes! Neat. Wouldn't mild steel be magnetic? Btw, I was checking by using a rare earth magnet. Them suckers will leap/slide pretty good when you get a piece of metal within a couple inches!

Rabbit hole, thy name is insomnia!!!

I've been trying to figure out how to winch the "mule", and thus the workpiece being cut, across the table at a "crawl" rate, from the same drive train that will spin a saw blade at 3,000-10,000 RPMs. I knew, somehow, that this was possible! So I revisited some YouTube videos.

The answer lies here, at around the 0:25~0:35 mark:


This one is longer, but more detailed. Same mill.


So from there, the rabbit hole spiraled downward through pedal powered machines, pitman arm, Singer sewing machines, and treadles, before finally ending on the Penny-Farthing. Not including several minor tangents in between!

I think the key to the mule will be to ratchet it like the wind sawmill does, but on a different scale. I wonder if I can rig up a lazy/improvised version using a spare ratchet & socket combined with a pitman arm on a pulley wheel attached to the end of the first shaft of the drive train?? Seems legit.

Time to try about a fifth time of going to sleep.......