Dimensional Print Studio

Zeitmeister (Not 3D Printed)Very high-resolution 3D printing is associated mostly with layer height designated as Z in most systems. There is also resolution in the X/Y plane. FDM filament printers control X/Y resolution with nozzle diameter and flow rates.

With SLA resin printers, X/Y resolution is the size of the laser spot or focus point. Laser power levels and slow travel can cause light “bleed” and affect the effective dot size very slightly. Generally, the spot size is fixed by the design of the machine and the laser.

DLP and DLM (Digital Light Projection and Digital Light Masking) resin printer dot size is fixed by the number of pixels and their projected size. One to one is the highest resolution but it is possible and common that the image has less pixels than the hardware. A 1K image on a 4k screen, enlarged to fill the screen, is still a 1k image.

By far the most common and manipulated resolution variable with every type of 3D printing is the Z layer height.

There is a very serious factor to consider when attempting very high-resolution 3D printing. That factor is printing time. Time increase as the cube of the size and in inverse proportion to the layer height with FDM printing. Double the size and halving the layer height (Four time the number of layers) could take 16 time longer!

Large FDM printers (prints) and super fine resolution are just not practical together.

DLP and DLM print time are ONLY affected by height and number of layers, and NOT X/Y size. Doubling the height doubles the time. Reducing layer height by 50% does not again double the time as exposure times decrease as layers become thinner. Rather than 200% longer print time, it may be 190% longer.

Doubling the size and reducing individual layer height by half will be 3.8, say... something less than four times longer print time.

Good FDM printers will produce 100um (micron) layers. I have seen claims for as small as 50um. But doing any print of reasonable size, say... within 64 cubic inches (4x4x4) at 50um will take (just for comparision) perhaps 32 hours. The Resin DLP/DLM printer could probably do it in half the time 16 hours) or better as it does a complete layer at once without X/Y travel.

My general rules:

Large prints, 100um to 400um layers then FDM (filament) printing

Small prints, very fine resolution 10um to 100um then SLA, DLP, DLM (resin) printing.

Otherwise, pay the Zeitmiester (time master) his due.

I just finished building a working prototype laser hand gun (pistol) using 3D printing. The laser is one of those laser pointer sticks used for slide show and teasing cats. It IS a real laser and I built a pistol shaped holder with a trigger to energize the laser beam. The only damage it is likely to do is to someone’s vision if they looked into the emitter when it is turned on.

Also, the fact that it now looks like a gun could get the user killed if they pointed the device at armed law enforcement and energized the beam. It’s almost harmless and makes no gunshot noise, but if I was a cop and saw what looks like a pistol with a red targeting beam coming from it, I might shoot first and ask questions later.

SO, this LASER device is not a TOY and needs to be deployed in a disciplined matter. It could get someone holding it killed.

My plan is to use it to persuade some nesting doves to stay away from my porch. Every year they try roosting, drop their bird crap all over tables and furniture and everything else on the porch, as well as dropping hundreds of nest building sticks.

I think nesting season is over this year but will try the red laser if they try again. It’s a war between me and the two lovey dovies.

Back to the laser pistol. The first prototype worked as intended. It was ugly and square and very hard on the hands to hold because of the square corners and 90-degree edges. I was interested in getting the trigger to function and not the appearance of the case.

The laser pointer has a small push button in an awkward location towards the LED end of the case, so I built a basic version one prototype just to test and find a way a trigger action could be utilized to energize the laser beam. That problem was solved after testing several variations in the first prototype. Version two includes the final trigger design and rounding the sharp corners on the body, making it more comfortable to hold and use.

There is a slight and satisfying audible “click” when the laser is switched when squeezing the trigger pull. Accidental activation is not dangerous unless one has their eyeball peering directly into the end of the laser at very close range. (Again! This is NOT a child’s toy!)

That’s version two in the pictures.

The bands around the front and the handle are to hold the case together. There are no metal parts like metal screws used. All parts are 3D printed PLA plastic. The only metal is the laser pointer.

It’s not designed to be an X-ray non-detectable stealth gun. Someone is going to think about that with all the media negative hyper-propaganda about 3D printed plastic guns. The appearance is that of a 3D printed gun, so it is best treated as if it were lethal. Read again the second and third paragraphs above.

I am considering NOT putting the .stl files openly on the internet. There seems to me to be too much liability with shoot-first cops and child’s play even if it is a low powered device. I watched my pre-teen granddaughter “role-playing” with it. She was totally safe, and maturing from child-hood, but I could see where it might go with a similar group of peers of any age, showing off and passing it around without proper instruction and self-discipline.

Use is far from my control, but I am aware of the risk potential. My case design is safe, and I am not providing a source for the laser device.

WOW! So much concern over human stupidity and ignorance.

I enjoyed the project and working out the simple design. I loved using FUSION 360 for the CAD and printing the prototypes on the Anycubic Kossel (delta) printer.

All parts are 3-layer shells. The trigger and switch are 40% fill and the case halves are 20% fill. All layers are 0.20 MM. The material is PLA plus. ABS would work well if printed with NO warps. No supports are required.

The design and trigger configuration are 100% original. This project typifies the sense of accomplishment creating a product from initial idea to functional operation. Truly making something, starting from nothing, start to finish.

Lovin’ what I can do when I try.

New PETG print after nozzle change.Been messing around for two days trying to figure out how to get decent PETG prints off my A/C Delta printer. Then I remembered my PLA prints were looking a bit crappy for quite a while, too. But PETG is a far fussier material than PLA, so I was thinking, doing a little mental math… 2+2=3.14159265…

Then I looked really close to the printing going on with the top layers on the current test PETG print I was running. “Dang! That nozzle tip looks awful short!” I said to myself.  It’s drawing the shoulder of the nozzle across the top of the print!!

AH… 2+2=4!!  Now the pie is on my face!  The tip of the nozzle is worn off. That hole isn’t 0.4 MM.  It looks like at least 1.0 MM!!!!

Of course, I couldn’t see that at that moment, but it was obvious I needed to change out the nozzle.

With the (very) old nozzle removed, I was able to examine it under my photo microscope and grab these pictures.

The new on the left the old on the right. Think there was a problem there.  

Lesson learned… Just because it isn’t plugged, doesn’t mean it’s still good…  DUH?!

Yeah, that old nozzle probably made at LEAST 100 good prints or more. The quality was dropping but the present PETG really drove the issue home. I’ll be changing nozzles a bit more often now I see how they wear. 

I was wondering about how nozzles change with time as I was doing my test prints. I have read the claim that flow through them with stuff like carbon fiber wear the hole bigger, but it looks to me that wear off the end is also a big problem. It depends on if the hole is tapered inside or has a fairly long parallel wall hole. This may be a combination of both.

I also read that some nozzles carbon up inside from overheating and the effective hole diameter gets smaller. I bought an expensive steel nozzle months ago and have never installed it. Not even now. I have run a lot of wood PLA through the old nozzle, but it says wood does not wear out the nozzle. That old nozzle has seen PLA. ABS, wood, and PETG. After a good purge, they all flowed fine.

Months ago, when I was playing with printing test parts for a U-Build-It 3D printer, the same spool PETG was not printing quite like I expected. I just blamed it on poor S3D settings. It was probably the point when I should (could) have changed out the nozzle. That old one was in there forever even then.

A camera microscope is a handy tool for nozzle inspection and photo capture.	The left is the new nozzle. The right was exactly the same, now with at least a 4X bigger hole!

Now wiser than I was yesterday, this old dog can still learn a few tricks…