Printing tactile signs?

3D Fabrication
#21

I am told that 3D printers are not used for a few reasons. Speed, size, and compliance. In order to print them to the dome shape you need something like the SLA printer but it can’t print the whole sign or quick enough to be cost effective. There are flatbed UV printers that can print the raised braille in one pass but cost about $20k.

For the majority of these signs, like Spoonanator said, its drill (with the CNC) and press the balls. The slightly undersized holes actually form a vacuum holding the balls in place.

#22

I wonder if we could do the braille part on the higher detail resin printers and print the rest of the sign in ABS on the polyprinters?

#23

I like the idea of having the Braille not less obvious (ok, obvious, but doesn’t make my point as well). Having said that, I have no experience with anyone using such signs, I’m basing my comment on the notion of “why would it need to blend?” That’s rhetorical, or at least aimed at conventional usage, and not directed at Chris. I’m also glad to see us addressing ADA, and it’s related subjects.

#24

To be safe, limit it to just what is needed as shown in the illustrations. If on the same plaque there may be requirement that it also have braille or that it adds to the confusion.

I can’t think of any braille signs that had more than basic info and braille. Doesn’t mean prohibited. Could be mounted near the Braille sign or painted/vinyl decal on wall maybe.

I do like the idea of doors having one. Ideas for styles:
https://www.google.com/search?q=braille+bathroom+signs&tbm=isch&source=iu&ictx=1&fir=ppCQibY4zIdNpM%3A%2C9T-TNnGuZctzbM%2C_&usg=AI4_-kSEwsYOF1ilfexEK1Y4K-Bcsv6rcA&sa=X&ved=2ahUKEwitzaHdgKDfAhUkmeAKHdEhCkUQ9QEwA3oECAQQCg#imgrc=_

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#25

It might be more cost effective to just get a sheet of acrylic to cut on the CNC router and some braille balls. Can cut the raised letters and holes for the balls to be placed.

#26

Exactly! Do the signs need to be so fancy/expensive?

http://www.braillebookstore.com/Handheld-Braille-Labeler.1

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#27

Prusa has a GCode post-processor for inserting a pause at height command so one can swap filaments. I’ve used it and it works fine (on Prusa printers at least)

On a Prusa, this will ring a bell and prompt for the filament swap as well.

There is also a Cura plugin which does the same thing, with within the slicer:

KissSlicer has a Pause and Resume option, but I’ve never actually used it:

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Looks like it pauses until the Filament Out Sensor (the big yellow wheel at the top of the printer) opens and closes, indicating a swap of filament (and a warning to not accidentally re-close the sensor until the filament is actually changed out). Does NOT seem to move the head off of the in-progress part.

If you want to do it manually ( or write your own script), you can add the following line at the relevant point in the GCODE and pause the print for 1 minute:
       G4 P60000

(60,000 = 60 seconds measured in milliseconds)

or the following, which will pause until manually continued:
       M0

The former has the advantage of restarting automatically after a minute, even if no filament swap occurs, rather than stalling indefinitely. The latter has the advantage of pausing indefinitely. Choose your poison.

Note that neither the Kissslicer version nor either of the manual versions move the head off the print, so some burn-in is possible during the pause.

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#28

I made an OpenSCAD version of the DMS logo for 3D printing many moons ago (April 2013):

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#29

We’ve got that one lady (sorry – don’t know her name) that’s currently playing DnD with the Thursday night group. She’s not blind, but heavily vision impaired. She might read Braille.

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#30

I may be able to find someone if we do not have anyone internal at DMS. LMK.

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#31

We might through these as well …

http://www.acesign.com/custom-signs/ada-room-signs.php

#32

I did poorly choosing colors. Text / sign half-sized. Braille is the correct size. Low density / 50 precision.

I left it in the galley for inspection.

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#33

Thanks!

There are a lot of vendors who will make ADA signs. We can easily buy standard stuff like restrooms and electrical room. I’m trying to avoid having to pay for custom signs for things like classrooms.

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#34

Thanks for doing this. I’ll be there probably tomorrow and I’m anxious to see it. I welcome everyone else’s feedback, too.

Does this suggest that a different density or precision would have fewer ridges? If so, could you print just a couple square inch excerpt as a test?

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#35

There are four six parameters that can be tweaked. “Loops”, “layer height”, filament (e.g. ABS vs PLA), and printer (e.g. PolyPrinter vs Rostock) are the other four.

Density is literally the interior density. “Low” is 15%. The sign is mostly hollow. Except…

Loops is the number of times around the perimeter to form an outside shell. The “low density” setting has three loops. That is probably enough material on such a thin part that the side, top, and bottom shells form a solid part.

Neither of those is going to have much effect on the appearance. With “all loops” there will be a spiral from the outside to the middle like a vinyl record but the ridges will still be visible; they will just have a different pattern.

The precision presumably affects the appearance but I haven’t noticed much difference.

In theory a very small layer height essentially squashes out the ridges.

A side effect of removing the ridges is that that part will develop a smooth shiny surface. Which is counter to the ADA standard (non-glare surface).

There are matte / low gloss ABS filaments available. If the rest of the sign (especially the braille dots) is good we can try different filament.

In any case, that version is essentially the fastest printing lowest quality sign we can expect from our PolyPrinters. It’s what I had time to print and, hopefully, will generate some ideas.

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#36

Thanks for doing the experimenting and also for explaining the details to me.

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#37

I’m trying a galley sign with 0.05mm layer height. The bulb shape of the Braille is going to be hard to match with FDM. The SLA printers might be better for this depending on how this test goes.

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#38

@John_Marlow could you post a list of the text for the signs needed?

#39
#40

Thank you, I glossed right over that one. So… the 0.05mm test finished and it’s there but it feels like crap. Using a SLA printer is going to be the answer I think.

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The file I used is below. It says “galley” (created using the link I posted before).

brail-galley.zip (77.9 KB)

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