The K-Fab Kaleidoscope

[K-fab]

Wasn't sure where to put this so into the Litter Box it goes. This part of the forum needed a bit of action anyhow.

Suffering from major PBO (project burn out) on the Mini-Raptor. I'm tired of a what's turning into 7 year project. It runs, it needs attention to detail shit and I'm of short MR attention span presently.

Sooooo..... (stories should start with this line, correct?)

Every time we go to Jerome, AZ (google it - fascinating place, full of history, hauntings, mines and all sorts of cool little 'tourist' shops, not to mention some really good eateries) we stop in a place that sells Kaleidoscopes. They have everything from the basic old plastic toy that we bought at the five & dime to some really fancy pieces. I'm always intrigued when we go in and have to play with them.

A few years back, as I was inspecting one of the more "industrial" units, my pea brain went into whirl mode (visualize whirled peas!) and the little draftsman that hides out in the folds on the surface began drawing up stuff.

Kaleidoscopes are surprisingly simple objects. It's a tube that you look in one end and the other end either has "stuff" trapped in it or is open to the world and that's what you see. They have one to how ever many mirrors in them that run the length of the body. This is what reflects the incoming source and makes the funky divisions that you see. From what I've researched, three mirrors seems to be the "standard".

If the mirrors are parallel you see what you normally see when you look into one of these interesting contraptions. Taper the mirrors (smaller at the eye piece, diverging towards the objective end) and it makes what you see have depth - 3D if you will.

The little draftsman's been busy on and off for a while now.
Hmmm.... what to make it out of.
Well part of that's easy; Carbon fiber of course!
And since I'm using aerospace material (CF), why not throw in some titanium?

What looks good with black and ti? Brass of course. It'll contrast well.

Sat down at the computer and the little draftsman whipped out some drawings. Main cradle that sits on a base and holds a rotating tube with as yet to be determined stuff in the end via long carbon stalks.

The tube will ride on six bearings that fit into races on it. Low friction, trick action.

First thing first (duh... not like I'm gonna start with the second thing first and then do the first second) - fasteners. What are all the trick fasteners made of in motorsports? Titanium of course! And since they have to be trick fasteners, well... I made trick fasteners.

Two different fasteners are used:
10mm head w/6mm shaft, 4mm threads and 1.58mm (.0625") diam drive holes.
16mm head w/8mm shaft, 5mm threads and 3.18mm (.125") diam drive holes.

Fasteners prior to head detailing:



To ensure consistency I made a simple jig that allowed me to knock out the head detailing:





Bunch of fasteners (and one spare of each - I'm trained!)



Made a driver for them too as I can't use any sort of tool found in my box. I did have a piece of ti left over so why not use that?

It tickles me just how well the driver fits into the fastener heads. It's a perfect, snug fit that slips together/apart effortlessly if aligned correctly.









So how to hold... I want the body to spin, I want a stand, I wanna win the lotto...

Made a wishbone that will be the main support frame/cradle outta ti.

I like machining it. It's clean, machines fairly easily as long as your tooling is sharp. It's similar to machining stainless except that when it gets hot it doesn't do like stainless and become impenetrable. Hardened stainless gives the middle finger to carbide. I have been rereminded that ti is flammable and will do a great impersonation of magnesium and go poof. The thin stringers in the lathe are something you have to keep an eye on (until they go up then avert your peepers - that shit's BRIGHT!).



The ends on the cf rods are ti and the smaller fasteners thread into the ends, holding the bearing carriers in place. The cf rods are a tolerance fit into the ends and then the fasteners thread into both the ends and the ends of the cf rods, holding everything together nicely (in theory! - not tightened things down yet).

The cradle is supported by, you guessed it, more cf toooobing.

The large fasteners hold the cradle to a pair of heim looking brass pieces.



I recessed the heads of the larger fasteners into the mounts and also made back side pieces that look like the heads.



Here's the backside:




The base is held together with brass pieces - everything is a tight press fit. I'll probably throw a drop or two of really thin super glue in the joints on final assembly.

Pretty pleased with the way it's looking and how well things have turned out. (okay, I had to make two sets of the 'heims' - one was just wrong, the other got pulled out of its tooling jig and wadded. Shit. Same thing for one of the corner pieces. I though the vice was tighter...)





The body will sit in a pair of races that are supported by three bearings each. This shows one bearing on the race.



The bearings are attached to a pair of wankle rotor looking pieces that the body runs through and are mounted on the ends of the long rods.

Presently working on these pieces. I have the first one about a quarter done.

That's where I be at the moment. Headed to the shop to finish out the mounting pieces now.

[K-fab]

Today's work. I got the frame and body done. Now I need to work on the optics aspect - waiting on ebay to deliver...

Here are the ends/bearing carriers in process.

Testing the ring fit and movement. It's sloppy - surprising what half a millimeter does. New rings will be made.



First one removed from the mill:



Bearings and the other three fasteners in place:



Finished mount. Notice the pattern? I was very aware of what the cut surfaces were going to look like so I was careful of the cutter paths and directions. Came out well, I think.



Put it all together and see what we got:

[K-fab]

Da latest. Been busy making stuff and doing research on these silly things.

Gotta give Bullnerd credit for the squaring tool. Was discussing how it dragged as I rotated it and he said something about using a piston to square up a ring in a bore and it hit me.

I've had this piece of carbon wrapped aluminum on a shelf for 13 years (wow... been a while!). I'd done the layup and then the project got canceled and it became shelf occupier. Heck, it was still just out of waiting on the resin to dry stage - whiskers everywhere, lumpy surface, blah, blah. BUT, the piece of aluminum hiding in it was the perfect size for a ring aligner.

I know have a trick tool. It slides perfectly down over the body tube, it's completely square to the tube and it's covered in carbon fiber.





After using the tool on both ends it spins nicely. Thanks Bull!

Time to do something with the optic end.

The optics unit press fits into the end of the carbon body tube and the rings on the end of the tube pinch everything down as the piece goes in. Keeps everything tight and well aligned.
My first test piece ended up threading in well (learned a bunch) but there were some other issues with fit and tool paths. I also learned that I needed to slow shit down. No mo fires now... I had one little flaming piece of titanium attack my palm - HOT!!!



Here's the optics end of this thing.

Been a good machining day. No scrap. Got the object lenses all set up and the mirror holder done.

Mirrors fit into the grooves. This will be inside the body tube and there will be a similar piece on the eye piece end.



Detail on the mirror holder on the visible side. 1/8” cutter has cut enough ti & the corners aren’t sharp and it left a really cool micro ridge on each pass.
The overlap is only .175mm so they popped up.



Clockwise from 9: Mirror holder, optics body, bezel (with lens snapped in), other lens, lens spacer.



Mirror holding end slips into optics body perfectly. I can finger pinch it together but need a razor blade to push the edges apart. Yes!



Another view of the assembly:



Optics back in place in the body tube.



Bezel & lens screw in place so I can change shit out.







Brain storming on eyepiece end presently.

Found some interesting info last night whilst searching on how these things work.

Biggest aha was the use of primary reflection glass so the light waves don’t have to travel through the glass (secondary reflection, like most mirrors we use). It keeps the images brighter and more precise.

Waiting on a 12x18 piece and some cutting equipment.

It's supposed to be 1.5mm thick and really easy to work with - I'm just cutting straight lines so let's hope so!

Next biggest challenge will be getting the spacing between the two mirror holders figured out and getting the two ends clocked the same when it all goes together. I'll be making some .05 aluminum test fitting pieces.

Got one of the greatest compliments from TALON a couple of days ago that I've ever had.

"It's such a nice piece just to look at, the fact that it will actually do something is a bonus.
As you know there are 2 types of people.
The ones that will look through it and be amazed and the ones that will look at it and be amazed."

Dis shit’s fun.

[K-fab]

Final installment of this thread (or at least of this scope).

Time to work on the eyepiece end. Once again main body out of brass, titanium lens holder.

Knocked out the Ti piece first and got it close to shape/size and ready to finish on the lathe.





This ring fits in this end:



And you end up with this:



Waiting on mirrors at this point but other than that it’s done.

Had to make the pin driver to remove the Ti ring. When you machine both pieces at once (blends really well) it gets surprisingly tight.





The scalloped ring is the eyepiece end mirror holder.



Eyepiece isn’t pushed all the way in yet. Don’t wanna damage it trying to take it apart.







Installing the mirrors is going to be interesting.

Done but needs tuning.



One mirror is flexed ever so slightly so it causes distortion.



Not quite sure how I’m going to fix it. It’s assembled and I haven’t figured out how to pull it apart w/o screwing it up.

Mirror cutting is an art and I’m paint by numbers level. Wish I’d ordered 2 pieces of it.

The media needs to be changed to something brighter.

Looking in the other end is actually pretty cool too.

Honeycomb pattern is the .5mm lip that holds the mirrors in place. This pic has no media in the optic end.



Would take a very precisely cut mirror and machining to hold the glass by it's edge instead of captured.

Really learned a bunch as soon as I got the mirrors set in the floating end. Getting the other ends into the grooves was a trip. Was almost impossible to do visually.

These two are from the optic end looking at the eyepiece end. (backwards, if you will).





Whilst researching these optic marvels I found that you can use any sort of mirror setup and that some work better than others.

Took the last piece of mirror and managed to cut two pieces that fit well with a strip of aluminium in place to hold them from moving around.





These are just pix taken through the left over made unit. The "tunnel" is the aluminum piece (I polished the surface best I could).

Using the finished kaleidoscope as the focal item:



"I'm a turtle!"



How about a sleeping cat?



Emojis on the iPad:



Plant sitting on the table:



Need to order a couple more mirrors and some more brass. This "parts unit" will end up becoming something.