A few I enjoy, and a few more in the works
Plus when Granite Gap is up our 20"RC robotic ;>(
20.53N 100.45W San Miguel de Allende
Nexstar 8se (Garfield)
NPL 30, Elux 25, X-CEL 18, 12.5, & 8
AstroZap Dew Shield
Zhumell red LED keychain flashlight
Celestron Moon Filter
Really bad sense of humor
"Gravity" another word for "incarceration"!!!!!!!
Quote:Don, why dont you open another thread on your focuser design, I am sure it will generate a lot of interest, with diagrams too.
Jc ATM 10" F6.1, 1/25th wave spec (max wavefront error +/- 1/12.6 in zone 4 of 6, sodium light ), 6" F7 spec, 127mm F9.4 achro Refractor, Criterion DX8, 10 x 50 bin, SP mount/Synscan goto. ETX80 (finder) Canon 20D, PST DSI 1, Butenschön 125mm F13.4 refractor, diy spectroscope and curiosity
Quote:Orion already has one
Quote:Quote:Orion already has one Why no patent? Prior knowledge?Don
Equatorial Newtonians, 20" and 14" "The purpose of life is to be defeated by ever greater things." - Rielke
Quote:I did think of it independently but do not fool myself that it is original, I posted it for interest only.
Quote:IMO idealized kinematic principles are only realized on paper in or in low load laboratory conditions. In the real world with real world loads (e.g. heavy camera) the assumptions used when applying idealized kinematic principles simply break down.
Quote:Three points of contact is the same as for a table or stool - three legs are sufficient.
Quote:Quote:Three points of contact is the same as for a table or stool - three legs are sufficient.Yes, for a relatively flat surface 3 points are fine - but you can slide a tableor stool in any direction.For a cylinder, where you want to constrain it to linear movementparallel to the cylinder axis, 4 points are necessary.
Quote:See reply by starcanoe above where the explanation is clearer than the one I gave.
Quote: I agree the statement is based on a profound well of ignorance. If you support a cylinder on three points two will be in a Vee form and the third must touch the cylinder further back and on the centreline, it will work fine as a tripodial support, but what is there to stop the cylinder sliding off to one side.???
Quote:Jon claims its not stable, it is. The rotational constraint would be applied by the drive roller on top. The Crayford will also twist on its axis with out the pinch roller.
Quote:My photo was illustrating the point that three points is stable. The implementation would have to be on rollers anyway.