10/25/2025 - decided what it will be like

I've decided to make a 3d printer
I want it to be coreXY with a relatively large build volume
for less than $350
I also want it to be somewhat fast but it must be precise too.

well apparently I need to do some more explaining, so here we go.
I was interested in 3d printers and decided that I wanted to build one myself to learn about all of the components, both hardware and software. so this is my attempt.

I asked a friend about the best kind of printer and he said that coreXY would be the best design for speed and accuracy. I wanted to do a large build volume because the coreXY system was easy to expand, and my prusa was too small.

the goal of less than $350 never happened, so whatever.

as mentioned, my prusa was also slow and so I wanted it fast.
The hour count is deflated so whatever

10/26/2025 12 PM - made mockup

figured out how coreXY worked with a mockup of the mechanism.
Researched parts to find how it would work for a reasonable price
decided that I wanted auto bed leveling and calibration

10/26/2025 8 PM - met with Tacomakes3D

I met with Tacomakes3D to find out how this project should be done
through his guidance i was able to better define what i wanted this to be like
he also helped me with deciding how it should work

10/30/2025 - did a whole ton of cad

I cadded the frame, coreXY, and Z axis. I decided to use a combination of linear rods and linear rails for precision in the coreXY and cheapness in the z.
I worked more on what parts I want in including the motors (nema 17 60mm).
the belt tensioner was especially fun to cad.
will work on mates next

11/2/2025 - More cad

I replaced the 2020 extrusions with 2040 extrusions.
I also reworked the mates
also I researched different extruder and heatbed options, many of which are too expensive, so i will have to find something cheaper.

11/7/2025 10:04 PM - worked on finding out the extruder/ hotend

worked to find an extruder and hotend.
decided on direct drive and a high flow nozzle.
also decided to run klipper on it. so that will require a raspberry pi.

11/7/2025 10:10 PM - met with a 3d printer expert

Was at orlando maker faire and met someone who makes delta printers (https://www.deltamaker.com/)
and spoke with them about how different very large printers worked.

11/13/2025 - BOM

fixed some floating belts in the cad.
worked on the BOM, it is still incomplete and requires more work.
It will still be a lot of work until it is ready though

11/19/2025 - worked on cad

did a lot of cad.
I switched out all of the 415mm extrusion for 400mm extrusion.
most all of the 3d prints got changed because of this.
I did some more research into parts and apparently it is cheaper on Amazon than AliExpress.
I also worked to optimize the BOM.
this was over a few days

11/21/2025 - fixed the cad which had gotten really broken

So apparently changing out the extrusions really messed up the cad. so I had to spend 5 hours fixing the dimensions, alignment, 3d printable parts, etc. the z rails proved especially difficult.

11/25/2025 - worked on cad

oops, I need to make better journals.
So anyway, this time, while slack was down, I got to work just making the cad work. I added some more structural brackets and fixed the feet. There were some extrusions that measured 455mm, so I shrank them to be 450mm long, to be cheaper.I also had to touch up the belts because of this.
I removed the tensioner and will be moving it to elsewhere.
I decided on a bambu hotend.

11/26/2025 - Did a little bit of everything

In this 2 hour block I put a fan and bl touch on the hotend and figured out how to make the fan duct. both parts were added to the BOM. I also added more structural brackets. I also decided to change to nema 17 48mm steppers because they were cheaper for not much torque loss. Also the tensioners were removed and will be replaced elsewhere.

11/28/2025 - made the hotend look nice and connected it to the belts

I made a nice looking(ish) cover for the hotend and made it able to connect to the core xy. Now it looks symmetrical and more worth 300-400 dollars. I attempted to make some decorative covers for the printer but that didn't work.

11/30/2025 - DID A LOT OF STUFF (that took surprisingly little time)

In this 6 hour block (spread across multiple days) I made a bunch of improvements to the cad.
One of the first things I did was to add a filament spool holder to the side of the printer to hold 1kg of filament on it.

I also constructed a port for the ptfe tubing in the hotend.

(If you haven't realized by now, it will be bowden (yuck) because it is cheaper.)

I also put an ender 3 extruder into the printer because it is cheaper than anything else that I could buy or make.

12/14/2025 - got it nearly done

So in this block I (spread over like 2 weeks) managed to get the cad mostly done. things mates, bad parts etc. The BOM also took a large amount of this time, trying to find all of the required parts. It unfortunately went over $400 so I will need to pay some myself. Whatever.

12/15/2025 - ug.

ok so I got some more stuff into the cad, like boards etc. A benchy also found its way in. The BOM has also come closer to being done, with everything but the heatbed. problem: it costs $549.95, so I will need to optimize some more, I don't want to have to pay more than $100 myself.

12/16/2025 9 AM - DONE!

I changed out the bed for an ender 3 bed, because it is cheaper. I also finalized the BOM, ($610.25 or something) which entails my paying out of pocket for some stuff.
I also made a simple box to hold the electronics
I'm now going to make the repo

12/16/2025 11 AM - did the repo

I put everything into the repo and set it up. the firmware provided extra trouble, because it was provided in a different repo. I also got everything ready to submit.

12/17/2025 9 AM - revised

No problem, thanks for the feedback! I've fixed the README and the cart screenshot. Unfortunately I'm not rich, and need this grant to buy the parts to build it, making posting images of the build impossible. I have updated the repo with the order of building and instructions to follow the cad, which is what I will follow. As you request, I, after building, can update the repo with better instructions.

12/17/2025 10 AM - G' morning reviewers

Hey guys! I'd be great if you read the notes that I put in for you! If the system is broken, here they are now

If there is any problem just let me know!
Unfortunately this does not meet the hour recommendation for tier 1, and I have seen projects rejected because of this, I had a lot of help throughout the project, so it went faster than expected. I also forgot to log some time but whatever. I am only requesting $400, the tier's amount, because I plan to pay some out of pocket. for me, it ends up cheapest to buy parts off of amazon, because I have prime and can get free shipping, reference https://hackclub.slack.com/archives/C09CMJV6V6K/p1763603033790629.
If you don't want the grant money spent on certain items, just dm me and I can pay for them myself. remember that this is a submission for review of the design!

I, also, am unfortunately unable to provide a video of it not working, because I haven't built it yet. Note the button.
I am not yet in the build process, I am asking for money to build it. Nor can I be more descriptive in the build process, I haven't built it.

If you read the notes (above), you will see my saying

I am only requesting $400, the tier's amount, because I plan to pay some out of pocket.

this means that I only want $400

Anyway thank you for your time, If there is any >real< problem please let me know!

12/17/2025 2 PM - fixed that

Thanks Jay for the feedback!
So I'm not going to remove the filament from the bom, as it is a required aspect of the printer, however, I can remove it from the cart of the amazon order and fix the BOM to include a note about it being bought by myself.

12/18/2025 - lemme explain

WAIT! its my problem, I never wrote down a complete summary of why I'm getting amazon and not AliExpress etc.

REASON 1

I have Amazon prime, enabling me to get FREE SHIPPING on ALL orders!

REASON 2

because of import tariffs from China in the USA $$$

REASON 3

My dad doesn't like AliExpress, due to it's Chinese nature, and his cyber-security sensitive job. I just can't use it.

Please consider the above and look at the snippet from the notes and slack below.

for me, it ends up cheapest to buy parts off of amazon, because I have prime and can get free shipping, reference https://hackclub.slack.com/archives/C09CMJV6V6K/p1763603033790629.

REASON 4

this is the second to worst reason.
When ordering off AliExpress, there seems to be no quality control, verified authentic reviews, guaranteed product contents, etc. using Amazon allows for assurance of getting the stuff.

REASON 5

Worst reason, only includer here because it was part of my thought, you can ignore it.
AliExpress's prices are only a few cents/dollars cheaper than Amazon, and I would still need to request 400$, I would just need to pay less out of pocket. BUT, I am wiling (and even need to) pay a bit more myself for all of the above reasons.
but you can ignore that ^^^

I especially hope that you will take the family reason into consideration, as well as all of the above.
Thank you for all of your feedback and let me know if there are any problems that arise.

12/23/2025 8 AM - >sigh<

Thank you for the suggestion of making my own PCBs. however, I am new to making PCBs, and it would probably be ill advised for me to make a high power power supply. I am also not skilled enough to make custom electronics in the drivers and control board. Unfortunately, this is all of the PCBs in this project.
But, Just take a look at all of the other parts, I mean, that aluminum isn't going to cut itself!
I can assure you reviewers, that as a complete beginner to 3-d printers, this is rather complex enough.
If a PCB is compact wiring on a board, I will be doing the exact opposite, wiring a large complex machine, and making it work!
If this still is not enough, I have designed a simple devboard (pcb) and am willing to use it to wire RGB or something.
Thanks so much for the awesome questions!!!

Now time for the less awesome question.
AliExpress.
I know I had not acted upon the previous feedback (in fact all that I had done was to add the part about reading the journals to the notes.) However I believe that the reviewer didn't read the journal that I had just made.


If you so feel, scroll down to read this explanation below. If not, I will explain all that you need to know HERE.
My Father, due to the nature of his job, ABSALUTELY FORBIDS ANY parts from these Chinese sellers. In fact, just yesterday he threw away one small USB drive from Alibaba. I am willing to pay the difference!!! This printer would probably cost $500 from AliExpress. Only $100 less than Amazon. both of these prices are above the blueprint maximum anyway, it is just a matter of how much I pay.

Anyway, thank you and I hope you reed the part about my father. If there is any REAL problem, and you are SURE of it, please let me know.

12/23/2025 2 PM - Ok now I crash out

Thanks for the feedback, but the reviewer has brought up the complication $ times and I have responded 4 times. Is something broken? I have noted it in the notes (twice!) AND in the journals (twice!)

12/23/2025 4 PM - THANKS

lol ok, I'll look up the AliExpress prices
Anyway, thank you Iamalive for the feedback.
I've done that and, lo and behold we get

that's a littttle above the maximum, so I must decline the offer of

I've updated the BOM in github (providing the ali links as alternates)
apparently AliExpress overprices extrusion
the cart screenshot is still of amazon because this is still where I will get parts from, but we can see the ali prices.

if the Bom needs optimization just let me know
oh one last thing, I'm re-doing the notes so i'll dump the old ones here (they are a bit rude)

If there is any problem just let me know!
Unfortunately this does not meet the hour recommendation for tier 1, and I have seen projects rejected because of this, I had a lot of help throughout the project, so it went faster than expected. I also forgot to log some time but whatever. I am only requesting $400, the tier's amount, because I plan to pay some out of pocket. for me, it ends up cheapest to buy parts off of amazon, because I have prime and can get free shipping, reference https://hackclub.slack.com/archives/C09CMJV6V6K/p1763603033790629.
If you don't want the grant money spent on certain items, just dm me and I can pay for them myself. remember that this is a submission for review of the design! READ THE JOURNALS!!!!! IT EXPLAINS STUFF!!!!! ehem. In fact, i have included something in the notes to you about AliExpress not working. AND in the journals, but if you cant see those, the main reason is that my father FORBIDS AliExpress and ALL other Chinese companies in the house. If you want other reasons look above this in the notes and also look at the journals.
please do this and not reject this because of your own incompetence. Thank you. Apologies for the rudeness but I'm crashing out.

12/23/2025 6 PM - Hola

OOps, forgot to put it here
So the problem present in the past, what, 5 rejections was resolved with lamalive,
in the BOM, it ends up more expensive to buy from ali than amazon
here is some of the slack string


thats it really,

so the problem of
has been resolved (I hope),
for reference:

amazon total:

If there is any problem let me know
(is Lamalive reviewing at this?)

1/1/2026 - new total in bom

uh.....
guys I'm a bit slow, am I not. isn't it common sense to use prices from both. but I also have time so good.
alright, that was a good idea (thanks!), totaling the cheapest numbers we end up with
An interesting note, it ends up cheaper to get the board and the drivers separately on amazon than together on AliExpress.
I'll upload to the repo later

1/2/2026 11 AM - CAD

alright, lets see what I can do about the cad. I'm a little confused tho (the MCU was in it) but I'll make it more noticeable.
So I'm not smart enough to do things like wires, but I did get in a bunch of screws, something that had been left out. I also labeled the PSU in bright orange so it is impossible to miss. I also labeled the control boards, they are only flat rectangles because my poor laptop can't take full detail. if there are any details missing let me know.

(btw, there are some backwards screws, but I couldn't fix it so whatever)

1/2/2026 12 PM - updated repo

I've updated the repo with all of the changes. The new cad was uploaded, as well as updated pictures and the BOM.
as a side note, I also added some more explaining to the first journal.

1/3/2026 8 PM - Ok

alright, my explaining

Hold up! your asking yourself, he didn't follow any feedback, his cart screenshots still show Amazon, whats the deal with that? its because I'm not gona lie. I have calculated the price to find that the cheapest possible way to build it by combining ali and amazon is $527.71. that is still over the limit, and I will still be paying myself, I just chose my preferred seller, even though ali makes the price lowest, I want to pay the difference myself.

isn't good enough for you, alright I'll try to resolve with the reviewer, I believe it to be a mis-understanding.

note: I've asked on blueprint support and got
I don't know if this is correct, and I don't blame the answerer if they are wrong, but I'm gona assume that they know what the...
oh, answer from the past reviewer. I've asked

now, about the cad, I had included the actual stuff, but my poor laptop (a gaming one at that), couldn't take it. but that is no excuse, I'll see if I can fix the cad.

1/3/2026 9 PM - More, you guessed it, CAD!

Well, I'm not gonna say that I didn't warn you
so I've added the boards to the cad, and my poor onshape died a few times.
I finally got it to work, but I had to zip it to fit it onto Github.
And onshape was REALLY SLOW
I also updated the pictures in the repo.

1/11/2026 - ooo interesting. ok

lets see, to start you mention

To start off with, please make sure your BOM.csv exactly matches your cart screenshot - for example, you still have TPU on your BOM, and as a previous reviewer stated, we cannot fund that.

I hadn't changed the BOM because it was the BOM, and the cart screenshot was what I would buy, but you're right, that is a bad idea.
I'll split the BOM apart into 2 BOMs, one for the grant, and one for completeness's sake. I had originally kept the BOM full size and put "for reference only" on the row of items not in the cart. Now these items no longer are in the BOM (or at least shouldn't be).
now there is also

lets see,

Additionally, could you please include some sort of wiring diagram / chart / image or anything really showing how your electronics will be put together? Since you're not making a custom PCB, that would help add complexity and classify this as a Tier 1 3D printer.

uh... I should have done that from the start.
oops, I'll make that real quick
alright now we have a wiring diagram at wiring.pdf.

alright, next we have

Finally, could you please elaborate a bit on your README - it seems incomplete and I don't see it worthy of being a tier 1 JUST YET!!!

hmmm.....
alright, i've updated the repo and added a render.

2/18/2026 - Fixed that.

ooo...
That's a lot of good stuff, I'll just use this journal to break down what I do to fix the issues.
(you'll have to forgive me for the simple mistakes, I haven't done this before)

your firmware setup instructions are entirely missing! Klipper vs marlin is a choice but you should at least have one known working config and an explainer on how to actually use this thing

that is a good point, my repo lacked that.

BUT...

It would be easier to run marlin, over the usb line, so I'll set that up. and that would let me get rid of the pi and save costs, as well as making it easier for the user. I'll leave the pi in the cad so the option stays though.
that's interesting, it looks like the firmware I put in there was for the stepper driver, not the board, i'll fix that.
alright, I have the correct marlin and configuration (copied and pasted from the manufacturer's github, but with an updated configuration.h).
next we have...

Your x-gantry extrusions aren't going to hold; the plastic you're using is way too thin for the forces involved

oh yeah, the 3 mm of plastic holding the entire x gantry totally isn't a problem.
lemme fix that...

we now have significantly better gantry supports.

Your specs are very unspecific so its unclear what this printer is actually capable of

well, thats because I don't know what it is capable of. let's find out.

I asked AI and it said that it could move at 150 mm/s and handel about 4000 mm/s^2
added to repo

WAIT...

holdup, I didn't even say the bed size.
I've fixed that in the github, the bed is 235x235, but it has a 220x220 usable area. it is approximately 335 mm in build height, but for safety's sake only 330mm in height.

To that end, I fail to see how this is cheaper or better than most printers out there - it's $500 USD for a printer with no real improvements? Your extruder is severely underpowered for what you're trying to do

I don't know what I can do about that, but here I'll explain the design philosophy, and why I think it's better.
now, it's not designed to be the flashiest printer, or the fastest, but it kinah takes from prusa's philosophy of accuracy over speed. it also aims for long term reliability, upgradability, and maintainability. so it uses common parts that are relatively cheap. so it doesn't exactly need the fastest extruder on the planet, just one that is tried and true, as well as replaceable. as for improvements...
its tall, with a >330mm build height. the H2D isn't even that tall.
but lets take the ender 3 say, it's a clone of the prusa i3 family. is it better? nope. it is a bit cheaper though. but why else would you get an ender? because you can upgrade it, you can tinker it, you can do cool things with it.
but if you know any way to make it better, don't hesitate to let me know!
I'll put this philosophy in the github and fix that.

When you make printers that big, you're going to need a brace in the front, otherwise the gantry will flex too much

lets see, I was aiming for a prusa xl kindah vibe, verry open. but you're right, it's not to rigid, I'll take a look at that right now.
alright, I've added another extrusion to hold it steady

and then last thing

I could go on - this is not exhaustive, but there's still a long way to go! I would recommend checking out #infill for inspiration - there's a lot of 3D printing experts there!

will do, but next journal, this one is already too long, I've spent all day.

3/1/2026 - tried asking...

whelp, I asked in the Blueprint channel, and the only feedback was that it was expensive.
a valid point, but I've already addressed that.
I'm not asking in Infill because they seem to have only like 10 days left and I don't want to derail the channel.
btw: I've added a link to the onshape cad to the repo.