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The K-fab Kaleidoscopes
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 inside my pea brain has 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 should do the trick, it'll contrast well.
As stated, I've been designing ideas and contemplating just what I'd make for quite awhile. Turned out that I had a full three days sitting in a hospital bed with diverticulitis with little to do. Lemme tell ya, that crap's NO fun, so while sitting in bed, I pulled out my ACAD computer and the little draftsman that hides deep in the recesses of me brain whipped out some drawings.
The 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!)
Notice the bearing on the one fastener.
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.
Close up of the driver ends. First one is the large end that fits the body pivot fasteners and the second picture is of the end that fits all the smaller fasteners.
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 wishbone is what holds the three carbon rods that hold the rotating mechanisms.
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 carbon fiber rods.
The bearing carries in process.
First pic was proof of concept and tolerances. I put three bearings on the small fasteners, bolted two of them into the brass carrier, stuck the orbital ring in place then bolted the last bearing in place. The system works nicely.
Once the proof of concept was done it was time to finish out the carrier.
Time for some assembly to see how well this thing works.
As per requirements, I had to make a tool to seat the bearing rings as perfectly aligned as possible. I'd had a piece of aluminum with some carbon fiber wrapped around one end from a project many, many moons ago. It had been sitting on my shelf of "neat stuff that I've made but never finished or used waiting for just such an occasion.
A little bit of machine work and I had a slip fit driver that installs the rings perfectly.
Time to work on the eyepiece end.
Once again main body is made out of brass and the lens holder is titanium.
Knocked out the Ti piece first on the mill and got it close to shape/size and ready to finish on the lathe.
Unfortunately I forgot to take pictures of the threads on the eyepiece end and the eyepiece body. I've gotten really good at making .5mm pitch threads. They're super fine, extremely easy to cross thread and took quite a few tries to get things dialed in. I actually made a couple of testing pieces - one with male and one with female threads. As long as they fit what ever I'm threading on the lathe, I know the parts being made will fit everything else with the same threads.
This ring fits in this end:
And you end up with this:
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. Besides, who doesn't need another special tool?
Here's the view from the inside of the eyepiece showing how well the driver fits in place.
The scalloped ring is the eyepiece end mirror holder. It precisely slip fits into the eyepiece's back side.
The reason for the slip fit is that the mirrors have to stay perfectly in place. I was afraid that the eyepiece being a press fit would make it really hard to get the mirror holder aligned and not destroy the mirrors as I pushed the eyepiece in place.
Unfortunately I didn't take a picture of the machined back side of the eyepiece mirror holder but you'll see down a few pix what it looks similar too.
The eyepiece isn't pushed all the way in yet. Don't wanna damage anything trying to take it apart.
I also machined and knurled a couple of "turning rings" that allow for better grip and manipulation of the body.
View straight into the eyepiece.
Installing the mirrors is going to be interesting.
The objective end was fun. It's a container that fits in the opposite end of the body. It consists of a main body, two glass lenses, a spacer ring, a bezel and another slip fit mirror holder.
This is the mirror holder. The detailed side is visible from the end of the scope so I couldn't just leave it alone and boring. Added a few scallop passes and 'tada' it's pretty.
Here's the mirror holding side. This particular kaleidoscope is known as a three mirror equilateral, meaning just that - it has three mirrors in it and they're set up at 120 degrees from each other. All three mirrors are exactly alike. and they slip into the groove seen in the holder.
Assembled objective end without anything in it yet.
Here's the backside of the objective end with the mirror holder in place. Just as with the eyepiece end, the mirror holder floats very precisely as to not flex or break the mirrors.
Test fitting of the objective into the body. No mirror holder in place yet.
Inner lens, the lens spacer and then the bezel that screws in place with its lens in place. Here you can see just how fine the threads are.
Completed objective end in place.
The Orbital in it's finished condition. It's done but needs a little bit of 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).
As I was making my first kaleidoscope, a good friend of mine made what may be one of the best compliments of a project 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."
The eyepiece end of the Orbital
I'm a turtle!
How about emojis on the iPad?
Sleeping cat.
Plants on the table
Time to see what would happen next, so I sat down at the computer, milling machine and lathe and started whipping stuff out.
Being that I'm diving into making these, first thing's first again - fasteners. Gotta hold the stuff together somehow, eh?
Punch a couple buttons on the machines and before you know it I've a pile of fancy little F1 style fasteners. Thirty small and eight large:
Followed that up with a titanium ring to hold the glass in place (seals the kaleidoscope and keeps the dust out) and a driver for the bezel. I used the carbon fiber and aluminum ring installer tool for the driver. Put pins on the small end.
Bezel on the driver pins.
Okay, I admit a cheat. Trying to thread the eyepiece when the hole is off center requires a four jaw chuck on the lathe. I don't have one. The Ti bezel was pressed into the end of the brass. I had to make sure the lens fit perfectly so I didn't break or chip it. Got lucky and everything went together perfectly. Whew!
Now how to hold things... This had my pea brain a bit challenged. The first unit I made had a suspended body and wasn't bolted to the frame. This one needed to mount directly to the frame and be able to support the spinning object mechanism.
So I got creative and put a center ribbing in. It doubles as a place to mount to the frame and also to help keep the mirrors in alignment.
I began with a copy of the eyepiece end and then cut out the part that would interfere with things. I also drilled and tapped the mounting holes before cutting it apart.
Once I had the two pieces made, I glued and screwed them in place inside the carbon body tube.
Once again, I'm kinda sad that nobody will see the detail and work on the inside but that's gonna change on the next one. I'll window the body so you can see the detail and I'll cover the mirrors with some sort of fancy colored glass. Should make for an interesting look.
Here's the completed body and what's seen though it:
Next came the frame work. More brass, Ti and carbon fiber tooooobing.
Started out making the main mounts (alway make spares) and backing plates that followed the body diameter so everything fit flush.
The finished body and frame. The two support legs ended up being too short and replaced with longer units.
The TALON body next to the Orbital
Next came the object ring. Instead of spinning the body to turn the media in the object, I decided that I'd keep the body stationary and have an object ring that spun. This ended up being tricky too. I had to cut glass and as stated earlier, I'm a novice at glass cutting.
The object ring is held to the body with one of the larger fasteners, rides on bearings, has an aluminum center and brass ends. Started out with the center.
The object ring was threaded so it all screwed together.
Now it was time for the brass outer parts. Two pieces were machined.
Next came the glass work. How in the world does one make a glass donut? Break 5 attempts and have two work, that's how. Fortunately I have some cool jewelry tools so I was able to cut close to the right diameter and then grind to final fit. Didn't take long (two broken ones) to figure out that having a pattern to follow made a HUGE difference. I cut out some contact paper using the center of the object wheel and would stick it on the glass before I started any work. It let me grind precisely and I actually got pretty darned quick at making the round glass.
This worked well.
Now things got tricky (and why I made 5 attempts). I had to drill a hole for the mounting fastener to go through the object wheel. No problem, they make glass cutting bits, right?
They work great right up to the point that they don't. Pressure regulation is a very delicate process. The bit would cut through nicely until it got through and then "tink" and trash.
The next one worked. I drilled from one side about half way into the glass, flipped it over and then drilled from the other side. Cool! I have a small hole in the glass. And then as I was changing tooling in the mill I dropped it onto the glass. Shit. More trash.
I finally got two round pieces with small holes in the middle. That's a start. Now I have to open up the holes so that the head of the fastener fits. I used a diamond impregnated cutter and very slowly and carefully worked the holes until they were the correct size.
Once I got the center done, it was time to figure out what the pattern was going to be. Sharpie time!
Once the three pieces were done and threaded I made sure they all fit together correctly.
Time to make windows in the middle piece and the two brass outer pieces. It was a major challenge getting these pieces screwed together tightly enough that they didn't try to move as I machined them. Fortunately I was able to use a pair of small three jaw lathe chucks as wrenches.
Once that was machined, I put the glass and different "stuff" in and screwed it to the end of the TALON body. I'm pleased with the results.
Not too bad, eh?
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April/17/2023