20140921

Testing, Testing

I was able to put the crown to an actual test this weekend.

Put on the jig to test blade placement.  
This is a very rough quick test to make sure that the fork blades and steer tube fit in the crown (which they do - hooray!!).  What you see on the jig is a bit deceiving, as the crown was not automatically this perfect.  The material that this is printed in is flexible, and well...

Unless 80mm axles become a thing, this isn't going to fly.
I had forgotten to account for the angling out of the blades.  This is why I test things!

Also the jig shows the blades raked, whereas here you can see they're perfectly straight.  For this crown, the blades will have to be bent by hand, though I also have a version in the works that will allow for straight blade forks. 

Everything been adjusted and fixed in the model, and for the crown base it was mostly angles that I had to work on.  The clamps were a different story, and I had to make a lot of changes based on feedback (thanks Hrrundel!) but now they're a lot better looking and far more functional.  I'm going to do another check of the model and then send out a new iteration to print!

20140915

Takhion Fork Crown: Print 1!!

Well this is certainly exciting:

I really need a lightbox.
The first print of this arrived today, and it's pretty cool to be able to see and hold the real print after staring at it on a screen for so long! 

With working clamps!  
This rough print still needs to have its measurements checked and compatibility with fork blades tested, and once it's approved it will be wax printed for casting.  Unfortunately I won't be able to test it with fork blades until this coming weekend, but everything else can be checked and fixed before then.

The model is missing the textured edges that the original Takhion fork had.  I'm still trying to figure out if I'll put them in the final model or if it will be smooth.  
Only one clamp was printed because they're interchangeable, and these things are not the cheapest to print.  This particular crown was modeled to fit standard Takhion bars, but I still wanted to test them with 3TTT bars just to make sure things were lining up.

Success!
The final casts will be tapped for a bolt and have hinges installed in the clamps.  The upper clamps themselves will probably be 3D printed in stainless steel.

Passing the 3TTT test with flying colors.
This particular print is done with Shapeways' strong and flexible plastic for testing purposes.  It's based off of a Takhion crown, but the dimensions were referenced from a spare fork crown I had purchased from Nova Cycles.  The clamps have been slightly modified from the original Takhion clamps, but I want to try to have a version of those available to purchase in steel for those that need them.  

20140908

A few Takhion reference photos

Over the weekend I took a few photos of my Takhion Temp for a friend as reference.  Perhaps they might be useful to other people as well, so I'll throw them up here.

If you need Takhion head tube or seat tube reference, here you go!







20140906

Takhion Fork Crown Recreation: Rough Model Done!

So one of the reasons that I haven't been posting too much is that I was trying to finish this crazy thing, which every time I thought would go a lot faster reminded me that "hey, you're not a modeler" and then I'd start over.

So after more than a month of pushing around verts and sliding edges to get the perfect measurements, I have this to show for it:

Complete with clamps and everything!
This was modeled after a few Takhion forks and a spare fork crown I had lying around.  It's modeled to scale, and also currently modeled to accept 26mm Takhion handlebars.  

The main reason that I decided to do this is because I was curious about investment casting, and how cool it would be if I could design my own crowns and lugs and such and get them cast for framebuilding.  So, this will be my test.

A rather exciting side view. 
A sample crown model and a sample clamp model have both been sent to Shapeways for a test print.  Once these have proven to work the way I want them to, I plan to cast the crown base and possibly print the clamps in some nifty metal.  

There are a lot of factors that need to be tested with this crown - like, hey, will the fork blades fit?  Could it be drilled for brakes?  And so on.  I imagine this will be the first of many, many iterations to get everything just so.  The nice thing about working in 3D is that it's easy to measure things down to the tenth of a millimeter, and things can automatically stay symmetrical as you're working on them.  

Nope.  No brake holes.
I'm excited to see if this works, and what sort of possibilities it opens up if it does.  There are already builders out there successfully working with 3D printed lugs, and if they can do it, why not me?
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