GearHeads Corner

I finally got around to building Scimitar.  I used flanged bearings in the frame so the entire shaft moves instead of using a fixed shaft with bearings on the individual components.  I goofed up by not building an extended arbor at the weight location so I machined and epoxied on a couple of steel fender washers to manage the downward force.  It actually works pretty good and keeps the weight spool close to the frame.  I'm waiting for  another shipment of bearings to mount the vanes.  There is no finish on the plywood because I wanted to build Scimitar as a learning tool rather than wall art.  My comment to anyone building this project is to add extra set screws to the vane shaft components because the ratchet impulse is rather violent and can easily change the timing if not tightly secured.

Thank you Art for a great project and complimentary YouTube video.  I hope that you post the "Bat" project some day because I'm really interested in counter rotating concentric shafts.

Mark

Nicely done Mark.. Congrats..

Thanks Bob, I don't know why the last photo was sideways.  Is there a way to correct that when uploading?

Way to go - I'm sure there will be many more of various types to follow.

John

Awesome..!!

  As to the bat, I dont have the original drawings of the one I made, it was made as a test,
and made wrongly.. the release pawl I used is driven by magnets, but the real way to do it is
with a pawl thats the right shape, I never got around to correcting it because the damn thing is
so large I cant put it  indoors. BUT, if you guys want, I will take it apart and post photos of its
internals so you can see how it works.. It wouldnt be hard to duplicate in smaller version I suspect..

Art

Art,
Is that the one your wife had removed from inside?  ;D

Ken:

No, never was inside, I built it in the shop, and when I hung it I could see it was way too
large for the house.. didnt even try. :)

Art

Scimitar lives!
https://youtu.be/SM3Qky85c5k

Learned about timing, balance, bearings, shafting, shaft supports, recoil chronometer escapement tuning and placement of components using spacers.  All that from this one little project!

Thanks Art!

LOL, fantastic Mark..

  I always find it funny to see a Scimitar, the original hangs in my living room
and gets compliments from all that see it, and yours is so remarkably close to mine
its like seeing my livingroom expand out into the ether..

  Im really pleased it worked so well there, (yours may work a bit better than mine. :) )
Great Job!

  I agree with you, by the time you build a scimitar, youve learned so much your
ready for more complex projects..

  (How about the drawing robot one.. :) )

Art

Nicely done Mark... Looks and appears to work flawlessly... Great job


Cheers
Bob
:)

Art,

I would love to see the photos of your "bat" (and i think I'm not the only one... (grin!)

and Mark, thank you for posting your photos of your scimitar as well as your Clayton Boyer project...they were inspiring to say the least!

best,

kobi

Art, or anyone who has built a "Scimitar"  I understand the need for the bearings, exactly how many bearings are used/needed in the construction?  Does each component require two, one on each side of the part as it moves on the fixed brass rods?  Planning on trying to make one this Winter and need to shop for "parts".  Brass rods can be found in big box stores, have seen some bearings on-line.  Need to learn how many are used.  Hardwood vs Baltic Ply ? Also, can the "ticker" be made to run quieter?

Thanks again.

    Bill

Hi Bill :

  Ill have to make a count of what I used. I tend to overuse if anything. I get bearings from Ebay by the lot
when I see 1/4" bearing, specially if they have a flange. If a piece of wood is to spin on a rod, I like to press
a 1/4" bearing on front and back for strength , keeps the wood shafthole from denting and going oval.

  You can sometimes find bronze 1/4" collars and such that can work as well. Theres no real load, so its all just about friction and helping the wood stay in good shape. Not required, but I like ot add them. As to sound, one could put a
piece of felt on the impact zone.. should quiet it down, but then.. a ticker usually only gets run 10-15 minutes at a time to amuse visitors. :)

  So while I like to do both sides with bearings, its not a necessity. My vanes too were all on bearing ( only 1 ), but
they were only 1/4" thick, so only one would fit. The most important one is that central shaft, it has to spin freely..

Art


Art

Hi All,
I'm not as precise as many of you and in fact I have better luck with no bearings at all and no lubricant either and go for a loose fit.  I have a clock that's been since 2005 with wood on wood and just keeps on ticking.

My Scimitar likewise has no "bearings' as such however I do use brass tubing from the hobby shop and "piano wire" 1/8" for some of my shafts, I do that more for alignment than friction.

I pack my Scimitar to craft markets as a display piece and have no problems with it running - I do keep the run times short because of its noise.  If I wanted to quiet it down I'd try putting leather on the impulse face - that might work.

I have tried in vain to print out the files for Scimitar :'(   I downloaded multiple converters...no joy. My computer has so many "scimitar" files on it now I'm completely lost.
  Does anyone have one to one files that can be printed for gluing to wood for cutting on the scroll saw? Please help, I've pulled out most of my hair in frustration!! I've actually tried tracing the parts on the computer screen, but couldn't find a good view of total parts !!

Desperate,

Thanks,

Eric