New toy arrived.

[karbomusic]

Kary,

You do realize that in 500 years...this key ring will be unearthed in a landfill...and it will be believed to be the missing key in unlocking the secrets of the universe!
Scholars will devote their lives to deciphering the hieroglyphics! 

Nice job by the way!

LOL! I never thought about that!

[karbomusic]

I got a chuckle out of the face, and wife justification  lol.

alright karbo, etch me a tycobrehe pcb. we can work out a deal for price n shipping!  I have two transformers , and two chances, to get this right. I would just buy a repro but they are almost 300 bucks I think , out of my price range !

No problem I should be able to get it done by this weekend, maybe sooner depending. Will update.

[deadastronaut]

thats the nuts man.....cool new toy..

will it do clear stuff?

[karbomusic]

will it do clear stuff?

It does if you buy a role of clear ABS which I do have but haven't tried. That being said I don't know if there is perfectly clear but rather translucent. I know that each translucent has a base... translucent black, translucent white, blue etc. where trans white is like a plastic up:

[karbomusic]

I got a chuckle out of the face, and wife justification  lol.

alright karbo, etch me a tycobrehe pcb. we can work out a deal for price n shipping!  I have two transformers , and two chances, to get this right. I would just buy a repro but they are almost 300 bucks I think , out of my price range !

No problem I should be able to get it done by this weekend, maybe sooner depending. Will update.

Other than drilling the holes, these are done. Still interested? If so, I'll drill em' and send em'. I'll PM you as well.

[tubegeek]

Aww! Cool!

If you are into making custom knobs I'm interested - I'd love some of these sized for stompboxes:

[amptramp]

We had a demonstration of this at one of the London Vintage Radio Club meets earlier this year.  Everyone seems to have the same idea - this is the way to manufacture knobs that have vanished without a trace or to replace urea-formaldehyde knobs that stink and grow what looks like white mould or tenite / butyrate knobs that warp with heat.  You could also make male molds to make plaster molds to cast your own aluminum enclosures so you could duplicate commercial housings with recessed areas for knobs and angled enclosure fronts.

Plenty of uses!

[karbomusic]

Aww! Cool!

If you are into making custom knobs I'm interested - I'd love some of these sized for stompboxes:

I could probably model a nice reproduction of the above shape in one of my 3D apps but I don't know if I could get that surface quality and resolution at smaller physical sizes. The only way to get that type of smooth gloss is to process the printed knob in an acetone vapor bath, doable but probably at the expense of accuracy of the edges. I've done a couple decent knobs but nothing outstanding yet.

That being said, the biggest strength of the printer for me thus far has been utilitarian... widgets, jigs, tools, brackets, etc. In other words, producing things with high visual detail and resolution from a pro presentation standpoint is a little tougher but depends on what it is. When it comes to things I need though that don't need to be mind blowingly presentable it's the cat's meow. I needed an illumination source that attached in a particular way so I could see my prints better when printing for example. An hour later I had one of these that I designed from scratch which includes an internal piece that holds the LEDs and a snap-in lens using clear "ink:





Then I wanted to hang my tablet on the wall over my work bench so I printed some brackets...

[tubegeek]

I could probably model a nice reproduction of the above shape in one of my 3D apps but I don't know if I could get that surface quality and resolution at smaller physical sizes.

I took a look at what people are making on that Thing web site linked above, and it seems like the texture of most of the finished products is indeed a bit granular. Sort of pixellation in 3D I guess?

The only way to get that type of smooth gloss is to process the printed knob in an acetone vapor bath, doable but probably at the expense of accuracy of the edges.

I would have thought you'd 3D-print something smooth in a two-step process involving some sanding or polishing after the printing, and I guess that would certainly reduce the magical-fun factor.

Your practical gizmos are awesome! I can see how you'd start losing little bits and pieces of all your kitchen gadgets on purpose just so you can make the replacements for fun.

[Blitz Krieg]

urea-formaldehyde knobs that stink and grow what looks like white mould

is there anything you can do for these knobs?

[Fp-www.Tonepad.com]

Those are great looking prints.

[karbomusic]

I took a look at what people are making on that Thing web site linked above, and it seems like the texture of most of the finished products is indeed a bit granular. Sort of pixellation in 3D I guess?

Exactly. To be fair most of those examples were probably printed at draft quality just so they can get the picture up but the pixilation as you describe is still there in the form of lines. The max resolution for most is about 0.1 mm so that isn't bad really, it's just that it won't come out smooth as glass. It also depends on what you are printing and which end is up etc. (the bed side is usually nice and smooth). Like anything, it is absolutely perfect for some stuff, more of a challenge for others, right tool, right job etc.

Also, I was commenting on as-is out of the printer minus any post-print labor as to not lead anyone on. That being said, ABS appears to take sandpaper very, very nicely and rubbing it with a little acetone after the fact works wonders and makes it shiny etc. but that is additional work.

I would have thought you'd 3D-print something smooth in a two-step process involving some sanding or polishing after the printing, and I guess that would certainly reduce the magical-fun factor.

Yep, see above. It all comes down to time/labor and I wanted to present the printer as-is. If one wants to take some extra time to make it look much better then it is possible.

Your practical gizmos are awesome! I can see how you'd start losing little bits and pieces of all your kitchen gadgets on purpose just so you can make the replacements for fun.

Ha! I'm just waiting for something to break.

I did design some isolation sleeves for 1/4" jacks last night but haven't tried to print them. That's the kind of thing that is great, maybe I'm building a pedal and need something like that and can just print it and not wait for shipping etc.

I will try at some point to model a loosely copied version of the pictured knob above just to see what happens. Would be great if there were a datasheet because then I could model a near-replica.

[LightSoundGeometry]

there is your meal ticket..custom knobs ..I would buy custom knobs for sure instead of using the same ole cookie cutter ones ..what are the upscale one made in Chicago, teh chicken head ones?

[PRR]

> a bit granular. Sort of pixellation in 3D I guess?

These "printers" are super-crude "ink jets", only with more solid "ink".

If you remember the first DeskJet, the type was very dotty. The jets were fairly large. And that's working on a flat surface, with 9 jets running a raster pattern.

The first color inkjets had only a few hundred colors (no fine-fine control of dot ratio). If you printed your girlie-pictures on that, the smooth gradations of light-dark around the curves came out, yes, pixellated, jaggy, posterized.


The "3D printers" are ONE "jet". They may run a raster pattern (skipping unused areas) or follow concentric paths, to build a super-thin sheet. Then step-up the thickness of the sheet and do some more.

If the jet passes are too close it takes longer and gets blobby. If too far apart it gets gappy.

They usually do a "3D" part as a sequence of *flat* 2D parts, one on top the other.

As the "jet" dot thickness is hard or impossible to control per-dot, you either get a full-thick dot or no dot. You have some slight control of dot thickness for the whole job, but if it is too thin it takes to long to make many-many thin passes.

To really beat the dead analogy....... these 3D printers are like building with Legos. The "Legos" are small, round, and soft. Even so, if you print yourself a woman, her womanly curves will have Lego-skin. Gross in draft/fast mode. Better in slow/fine mode. But we are barely at the 600dpi level where laserjet text does not look dotty to the eye. Your tactile sense is much finer than the eye, micron roughness is very perceptible, and most touch-products are finished better than that.

The lovely curves on those knobs are just wrong for the process. SOME day we will have faster printers with dynamic dot control, and that shape can be done closer than "eh..". But that day is not here, not for most budgets.

I hate to be ol-skool (OK, I love it), but that knob can be copied about the way it was created. Modeling clay or wax, little wire shavers, calipers. There is a "clay" which hardens in the oven; however unless you only ever need ONE it would be wiser to use the sculpted knob to make a plaster mold. Then you can pack it with stuff (there are many modeling resins today) and turn-out a lifetime's worth.

Looking at that: I would start by lathe-turning the basic shape. It is just a funny bed-knob or drawer-pull. Then to the milling machine and angle-finder to hog out the seven finger-depressions. Then work a wedge of clay into the pointer shape and stick it on. The line-groove may be very touchy work. (Or you could set a very tiny blade in a plane barely bigger than a match-stick, to follow the shape with constant depth.) (Or saw-through, put cardboard in the slot, trace and trim, put cardboard back but tap in slightly below the surface.) (Good die-makers invented their own tricks.)

Lest you cry about carving clay/wax and plaster-- that particular knob-series was made in such quantity that I suspect some guy had to carve the negative directly in HARD STEEL. It isn't even a "big" job; a toy next to an automobile fender stamper mold. You take a bright light, a block of steel, and a die-grinder, grind out until you have a hole the shape of the outside of the knob. Since that knob was in use for 30 years and on some fairly classy gear, the knob company probably covered their costs on the die-grinding. But today knobs are a doomed device. Even pushbuttons are vanishing for TouchScreen (one of the worst interfaces ever foisted on us).

[tubegeek]

I will try at some point to model a loosely copied version of the pictured knob above just to see what happens. Would be great if there were a datasheet because then I could model a near-replica.

That would be amazing!

At some point I actually saw an RCA technical paper describing the development of that knob. They were very proud of how cool it is, as well they should be. I have been madly Googling to try and figure out where I saw it. I am on the case!

[PRR]

> saw an RCA technical paper describing the development of that knob

I'd be interested in that also. Can I email you some ice-tea to aid your search?

Idle thought you probably already covered-- RCA Review (and similar) on American Radio History ?

[tubegeek]

I'd be interested in that also.

I know, it was riveting! They described how the channels on the sides allowed the operator to rotate them with one finger if desired, etc.

Can I email you some ice-tea to aid your search?

Has to be unsweetened, but sure! I think you might want to freeze-dry it to reduce the packet count.

Idle thought you probably already covered-- RCA Review (and similar) on American Radio History ?

I found some RCA technical paper indices there but so far haven't hit paydirt. That'll probably be where it shows up although I don't think that's where I first saw it.

[tubegeek]

RCA Broadcast News November 1937
Starts on p.7.

[bluebunny]

^^^ Fascinating.

[karbomusic]

I will try at some point to model a loosely copied version of the pictured knob above just to see what happens. Would be great if there were a datasheet because then I could model a near-replica.

That would be amazing!

I don't know how far I'll get but I did get a very small start on the basics this morning. Keep in mind it's a work in progress but at least it is round.