The Printer

The Inspire 3D Printer Kit is being developed by Accessible3D to be the cheapest 3D printer kit ever. Our current developer kit is being delivered for $30, and I am hoping to keep the price-point as close as possible to that in the final kit, once developed. I was inspired when I saw similar products and felt I could do it cheaper. My hope is that if I can bring the price-point down, it will lower the barrier to entry for 3D Printing, and make this empowering tool more accessible. The Inspire 3D Printer is a small LCD Resin 3D Printer that cures UV-sensitive resin (designed to work with standard 405 nm resin) layer by layer to build a solid 3D object. On this page, you will find information about the Developer Kit, how the printer works, and my progress in developing it. It is still a work in progress, but I hope you will stay tuned here on my Shift4Shop site to see it all come together.

Developer Kit

I have paused developer kit sales right now so that I can ship out current orders and focus on future prototype development. I will open up once again when I have made some more design progress. Assembly instructions for the current kit can be found here: https://www.instructables.com/30-3D-Printer-Project-Inspire-3D-Printer/

The Inspire 3D Printer is still in development, and I am not yet in a position to offer it for sale in its final form. However, I believe we have made a lot of progress and proved that the concept is feasible with these inexpensive components. There is still a lot of work I need to do, but I wanted to open up the work I have done so far and raise funds for the St. Jude School Program. If you are an experienced maker and interested in getting involved in this work, you can buy a Developer Kit that includes all of the components for the current design excluding any 3D Printed Parts, which only takes about $5 worth of filament to print.

I want to be very clear, the prototype you can build with the components in this kit is not a fully functional printer in its current form. I have made a lot of progress, and I believe I have proved it is feasible, but it will not serve as a 3D printer right now. This kit is ONLY for experienced makers. UV-curing resin has some inherent dangers, and the kit will require access to tools like a 3D printer and soldering iron. I am working to design additional safety features and finalize the physical design to produce the mechanical pieces so that everyone can build and use it, but the developer kit is only for people who are experienced, want to prototype, and potentially contribute to the printer’s development with their own additions. I repeat, do NOT buy the developer kit unless you are experienced. I am working to develop the most Accessible3D Printer in the world, but this is not it, this is just an important step on that path. As I continue to update the design, I will try my best to only use the parts in the kit (which is why I am also including some parts not currently in the design, but I anticipate I will incorporate), so that you can update your prototype along with me.

You can check out the development progress below to fully understand the state of the printer prototype and its current capabilities. If you aren’t as confident as I am that I will reach my goal, then I would encourage you to hold off, follow my progress that I will document here, and order when I have gotten a little more work done (also check out the cool space-related 3D prints I am selling! The proceeds will also go to the St. Jude School Program).

Click the “Order The Developer Kit Now” link below to see exactly what’s in the kit, and when you can expect to receive it. By the time I ship the kits, detailed instructions on the assembly will have been put together. I will also put together an open-source product list that can use the instructions. I envision it will have some affiliate links that will not cost you anything but will still raise money for The St. Jude School Program. It will likely be a good deal more expensive than our kit since you won’t benefit from bulk pricing, but you can probably get all the parts a little faster that way.

If you have followed the 3D printer field as I have, you know there are a lot of projects that have failed to deliver (particularly the crowdsourced kind). You can be confident that you will get this kit because I am not trying to deal with any complicated manufacturing or tooling (I do want to do that in the future, but that is something I will work through when I get there). I am just providing inexpensive electronics already readily available packaged together and saving money by ordering multiple units that I have already priced and sourced for a small batch.


How does it Work?
Resin Printing in the form of SLA and DLP have been around for a while, in fact even before FDM Printing. An LCD Printer is related to SLA and DLP Printing in that it builds an object by selectively exposing UV light to a UV-curing resin. This means that when it is exposed to UV light - it hardens. This is done layer after layer to build an object.

In a basic sense, a Resin-Based LCD Printer replaces the backlight of a standard LCD screen with a UV light. More advanced LCD Printers will use Monochromatic LCD Screens since RGB LCDs will filter out some of the UV light which translates to longer exposure times in order to harden each layer. But small decently fine-detailed RGB LCDs are less expensive, so I accepted the longer print time for the benefit in cost. There are actually some daylight resins, that cure when exposed to wavelengths achievable by normal visible light LCDs (~460 nm), however, that resin is an order of magnitude more expensive than standard 3D printer resin, which is approaching the same cost per Kg of 3D printer filament. As much as I loved the design simplicity those resins would allow, I ultimately decided it made no sense to build the cheapest 3D printer in the world, just to use a prohibitively expensive resin.

Here’s a photo from 3DSourced that shows the basics of an LCD Printer. I will also link their article that explains the differences between SLA, DLP, and LCD Printing if you are interested.

https://3dsourced.com/3d-printing-technologies/sla-vs-dlp-3d-printing/

Does it Work?
We have successfully demonstrated that this can work at this price-point in our development. You can check the progress in the “Development Progress” section. I provide some more clarification below.

The less cheery short answer right now is no, it is not a functional 3D Printer in its current state … The longer answer is that up to this point, I have demonstrated that with inexpensive UV LEDs and an inexpensive RGB LCD screen, we can harden a layer of resin in a targeted fashion onto a build plate, raise that up and build another layer, and so on. At face values this is what a 3D Pinter does, we have to attach that initial layer to a build plate and raise it up and build another layer, and another, and another.

However, from my testing documented in the next section, you will see there are still some kinks to iron out. In our second full test, I was able to build a layer (made a small square), but couldn’t get that layer to stick to the build plate. So I made some adjustments and in the third full test was able to get it to stick! Unfortunately, the print also stuck to the plastic film at the bottom of the resin vat. As I raised the build plate up with the printer’s linear drive, the print kept sticking to the bottom of the vat until the bottom broke the adhesive holding it to the vat. This is due to shotty engineering on my part. Rather than using FEP film at the bottom of the resin, I was using clear plastic from some packaging I had laying around (If your gonna make something cheap - you better make it cheap!). In the fourth test, I redesigned the resin vat and ordered some FEP film. In this test, we were able to get the first layer to stick and build a few more layers on top of it, as you can see from looking at the outer edges, but there was some deformation and a break due to what I suspect is too small of a step in between layers. In the more recent test, I made adjustments to the prior issue areas and got a much better print-off. Still, some small deformaties that may suggest the linear drive needs improvement, but I am moving full steam ahead!

I am still working diligently, and hope to get a full 3D Print with no issues out by the end of the month. I believe my progress thus far proves, in my mind, that there is no longer a question of feasibility with these components, but just some work that needs to get done to help the prototype get to full functionality.

Development Progress (Scroll to the Bottom to See My Latest Work!)

Component Testing
UV Panel
LED always on. Testing if switching between white and black screens will impact the protuberance of the UV light (Really testing visible light here, will see about UV later with the resin).
Lesson Learned: We can selectively allow the UV light to pass through the LCD by setting portions of the screen to white.

Linear Rail
Check that we have enough fine detail in our prints to really deliver a functional linear drive, and I have to measure out steps to distance conversion for print programming
Lesson Learned: A fully 3D printed linear rail driven by an inexpensive stepper motor is feasible. Got conversion values.

Test 1
Let's give this a go!

Made the design before I got the screen. I was originally hoping to detach the leads from LCD to its board and resolder them together after putting the board somewhere else. Realized this was not feasible, so you can see some changes to the design will need to be made.

This is just a blank white LCD screen with a single UV LED to see if we can harden anything, or if an inexpensive LED like this is too week with the filtering of this LCD. Let it run for 5-10 minutes.

Test Setup


Print Results


Outcome
- We can make a blob!

Lessons Learned
- Harden resign through an LCD (this is BIG, I was concerned the LCD would filter out all of the UV wavelengths from this inexpensive LED)
- Linear Rail seems to work - though not very precise

Next Steps
- Full redesign
- Improve rail
- Actual housing for screen/electronics, not just hanging out the side

Test 2
Changes
- I went back and resigned the printer. I wanted to keep it small, but provide batter placement for components.
- Also focussed on improving the functionality of the rail, to keep it horizontal and smooth.
- Added in leveling feature on the build plate

LCD and UV LED example (building an example square layer vs. all black to move build plate up and down)


Test Setup


Print Results


Outcome
- We made a square!
- Rail slides smoothly
- Unfortunately did not stick to the build plate

Lessons Learned
- We have a 2D printer!
- Can selectively form shapes on the Printer
- You will notice that right above the LEDs there is a clear indication in the print there was more intense light - Will add a Fresnel Lens to address that in a later design
- See some surface tension keeping resin on the backside of the build plate, can add a minor slant in future designs to fix that
- Rough Metal Build Plate is probably the best bet to get it to stick there

Test 3
Changes
- Reduced initial starting distance and layer size
-Added Metal Build Plate

Build Plate (Same Test Setup as 2, so I will spare you that. I will include a photo where I moved up the plate so you can see the new build plate, and also evidence of the spill (bottom right) due to the build plate tearing the bottom of the vat from its adhesive)


Results (A Mess)


Outcome
- It Stuck … to everything
- A mess - Stuck to the build plate, but as it raised up, it also stuck to the bottom of the vat, causing the bottom to get riped from its adhesive to the vat and spill the resin



Lessons Learned
- As much of a mess this was, that needed to be carefully cleaned, I think this is huge!
- We have something that can build layers, and now we know it can stick to the build plate and raise it up. If we can get it to not also stick to the bottom of the Vat and repeat, we have a 3D printer!
- Ordered FEP Film to address the bottom of the vat, will need to redesign the vat to accommodate. Should eliminate sticking issue on the vat side.

This test proved in my mind that this endeavor is absolutely possible with these inexpensive components. And for that reason, I am releasing the Developer Kit so experienced makers can join me on this mission and start tinkering themselves. Go check it out above to see how you can order one and when you can expect to get it.

Test 4
Changes
- Redesigned Vat to used a replaceable 100mm x 70mm piece of FEP film
- Cleaned up wires and placed inside the housing

New Resin Vat (You can see the edges of the FEP film that has been trimmed on the outside)


Test Setup


Print Results


Outcome
- We got our first-ever print to stick to the build plate and build multiple layers!!!! This is approaching actual 3D printing!
- You can tell there are multiple layers by looking at the edges of the print on the build plate
- However, on the build plate, the shape is slightly deformed
- Then I discovered another well-formed square when washing the vat with rubbing alcohol. I was expecting a lot of potential things, but not 2 separate builds. This is an interesting result

Lessons Learned
- First I want to recognize how big of a step this is! We arguably made a 3D print!
- More importantly, each new prototype and test has been a big step forward and provided important lessons
- More into the issue: I will have to do some more experimentation to figure exactly what caused this result, but here is my first attempt at understanding it.
-- In between each layer we have the move the build plate up to separate the just printed layer from the film at the bottom of the resin vat, and then lower it back down to the proper layer height
-- This is because the film at the bottom of the vat has some flex to it
-- I was doing this, but only barely
-- I believe if was not lifting it enough to separate in between each layer, the film would remain flexed and attached to the print and build plate
-- Now for future layers, we are projecting the square on the LCD onto a curved surface, which the resin could attach to the build plate even if it's not all the same thickness
---This explains the deformed print on the build plate
-- Eventually, we would reach a point when the bottom film could not stretch anymore, and here it would finally separate
-- In the layers in between, they would be poorly attached to each other due to the abnormal nature of the curing
-- And so when we finally hit the breaking point and the film snapped back, some layers that were poorly attached to the layers above them would remain with the bottom film
-- This explains why there are two pieces with multiple layers even though the top piece was much more securely attached to the build plate than the bottom was to the film

Test 5
Changes
- Made changes to the code to increase lift in between layers

Test Setup (Nearly the same as previously, undid some of the wire handling to more easily make changes to the circuit)


Print Results (Cone under the print on the print bed is a drop of resin dripping down, not part of the build)


Print Outcome
- We are really getting close!
- It looks like these changes solved a majority of the problem, shape is still slightly deformed, however, far closer to the square we are trying to build
- No large piece left on FEP Film
- The Primary issue here is layer shifting and the deformation

Lessons Learned
- We are getting so close to getting our first issue-free 3D print out of this printer with components that only cost $30!!!!
- It looks like increasing the layer lift size solved some of our issues
- However, some of the layers are poorly built, or even slanted if you look at the close-up images
- The print bed does not move perfectly smoothly
- I think this may be the culprit of our current layer quality/deformation issues
- In some cases, one side of the build plate may be slightly lower than another as it moves along the rail
- This probably means we may be approaching the max capabilities of my current linear drive and will need to redesign a new one that includes things like plastic BB's as I had discussed as a replacement for ball bearings. (Or replacing entirely for a cd drive)

Z-axis Print
Thank you to everyone who has ordered a kit so far! I have spent most of my time on this project over the past week managing that, but have had some time to work on an updated Z-axis.

Still have some work to do here, but wanted to share a recent prototype I have been pleasantly surprised by. The idea here was in working towards a final design to minimize the need for a lot of custom 3D printed parts. My current thinking process right now is that if I can isolate the z-axis components, then everything other than that, the build plate, and vat, will be flat. This could make building it a lot easier and quicker. Also trying to incorporate an actual threaded rod (hopefully that will suffice for these needs over a ball screw) and linear rails as I think they will improve precision and solve some of the layer issues. I saw an interesting video using pencils of all things for a linear rail and decided to give it a try. Do not worry, I will include a metal option in the future, but I wanted to see if that was a feasable inexpensive alternative. I have been surprised by how well they have worked, however, I anticipate they will have a very short life-span which may negate the cost-benefit. The whole assembly right now is only about $3, which as the only moving part, is not bad at all.

 

Next Steps
I am still working towards our first real 3D print, without issues, off of the printer.

Then I need to go back to the drawing board a little. Much of the design was developed quickly, to get prototypes out and verify the feasibility of the concept with these inexpensive components in less than a month. I also have to think forward. The 3D-printed lead screw probably is not a good long-term Z-axis solution. I was looking at something like this: https://www.thingiverse.com/thing:2967644 or replacing that 3D printed assembly altogether with a part derived from an inexpensive cd stepper drive that can be picked up for ~$2 which is less than what I have budgeted for the current stepper in the design.

Once I have done that I will need to revisit some of the components since many are friction fit and sliding. I have been evaluating the use of small plastic “bb’s” as a sort of ball bearing to improve the linear drive and will need to design in screw holes/nuts and bolts to make the design sturdier rather than friction fitting as I did to speed up prototyping.

The electronics are also a nest of breadboards and wires. With a mass order, it would become feasible to produce custom PCBs to simplify the assembly and clean up the design. However, I am not super worried about this. At worst, I will provide very detailed instructions on where to connect wires, and the person assembling it will hopefully learn a little in doing so.

I am also currently evaluating how to make the final design as safe as possible to use. While this form of 3D printing eliminates the burns and fire risk inherent in FDM printing, uncured resin can be damaging to the skin, and it is certainly not advisable to look with the naked eye at UV LEDs regardless of their power. To address the uncured resin, I have been considering implementing a rubbing alcohol bath on top of the side electronics pannel for easy placement immediately after a print, and even the possibility of a pivoting linear drive to allow for placement in the bath without having to touch the top build plate screw. This would be on top of basic safety precautions like wearing gloves, which I plan on shipping with every kit. A few additional UV LEDs could also be added to this bath to help with final curing. A common safety measure for UV light is a UV-protected enclosure, once again on top of basic safety measures such as UV-protected glasses which I plan on shipping in every kit. These measures could raise the price point slightly, and while I am committed to keeping the price as low as possible so that it is accessible, I cannot compromise on safety.

Then there comes the software side. I chose an ESP32 as the primary microcontroller because it is inexpensive, and has Wifi + Bluetooth connectivity. That means we can control the printer with a phone/computer which should make it easy to use and monitor (also saves us from having to buy another screen and physical buttons for control). I need to develop this web interface to make sure we can monitor the progress of the print and upload files. Up until now, I have been printing simple shapes that could be hard-coded to test out the printer prototype. I will need to develop some more sophisticated software that will support essential maintenance functionality and handle slicer output on the printer's SD card so that it can then interpret and print whatever you can imagine!

Longer-term I have to start keeping an eye on manufacturing. Injection molding is really only going to be feasible at this margin if I sell A LOT of printers because of the high fixed costs. I think if I can minimize the number of 3D printed parts, it should be feasible to do a minor 3D printing farm at scale for a limited number of parts while trying to maximize inexpensive structural components already in production and fill out the rest with flat pieces since that should be a lot easier produce by laser cutting or other means. I envision these components will drive the price up some, but I do not believe I should have a problem keeping the printer at the cheapest ever (the lowest I can find anywhere is $95)! If successful, I think I could expand the business to larger print areas, supplies, and provide subsidized options to teachers and students if whatever the end pricepoint ends up being still remains prohibitive for some.

Stay tuned to this page as I continue to provide updates! You can also sign up for our mailing list in the bottom right corner!