Upload and print

The /print page takes your own file, validates it, weighs it with a real slice, and turns it into an order we print in Austin, Texas and ship to you. You choose material, colour, quality, quantity, scale and infill; the price comes from the grams the slicer says will leave the nozzle. You do not need an account to upload and see a price. You sign in to order, because the order is billed to an account and filed under it.

What you can upload#

A mesh must fit the plate: 340 × 320 × 340 mm on a Bambu Lab H2S. The three dimensions are sorted before they are compared, so a part that only fits when rotated still passes. An already-sliced file skips this check entirely — your slicer already arranged it on a plate, and the footprint it reports can include purge lines and prime towers that are not part of the model.

How the upload works#

The bytes go from your browser straight to storage, not through the app. There is a 32 MiB cap on request bodies in front of the service, and anything over it is rejected before the app ever sees it — so a 100MB model could never arrive as an ordinary POST. It used to fail as a confusing validation error rather than a size error. Now the app hands the browser a signed URL, the browser uploads to storage, and the app validates the stored object afterwards.

1. 1
   The page asks for an upload URL

   It sends the filename and the size. Format and size are checked here, before a single byte moves — an unsupported extension or an oversize file is refused now rather than after the transfer.

   jsonCopy

   { "fileName": "bracket.stl", "size": 48213004 }

2. 2
   Your browser uploads to storage

   A signed PUT URL comes back, valid for 15 minutes, pointing at a staging path. The transfer is browser to storage, so its speed is your connection, not ours.

3. 3
   We validate what actually landed

   The app measures the stored object itself rather than trusting the size the browser claimed, parses the bytes that actually landed, and only then copies the exact bytes it validated out of staging into their final path. That copy is the point of the staging step: the signed URL stays writable for its full 15 minutes, so validating and printing from the same writable object would let a small part be priced and a large one printed.

4. 4
   The model is weighed

   As soon as the file is stored, a slice is queued in the background. Until it lands the page shows Calculating, because showing an estimate and then quietly replacing it reads as the site changing its mind about the price. Move the scale slider and, once it rests, that size is sliced too: the weight line reads Weighing at 300% until it lands, and a size you have already weighed comes back at once.

Uploading without an account#

Signed out, you can upload, import from a link, move the scale slider and check a project's colours exactly as a signed-in customer does, and every price is the same real slice. The page remembers your uploads with a cookie in this browser rather than an account, so it needs cookies allowed for the site.

• Press Print & Ship or Add to Cart and you are asked to sign in or create an account. Your choices are kept, and when you come back the upload and its quote are moved onto your account without uploading the file again.
• Only the browser that uploaded a file can see it. A signed-out upload is not in anyone's history and not in the community gallery.
• Uploads you never sign in to claim are deleted after 14 days, the record and the file together.
• A signed-out browser can upload 10 files an hour and 30 a day, and import 10 links an hour. There are also limits per connection and a daily ceiling across every signed-out visitor. Each refusal says that signing in is the way past it, because an account has its own, larger allowance. File size limits are the same either way.

What the quote is computed from#

Weight. One all-in rate per gram covers filament and normal machine time together, so a 21 g PLA part costs exactly 21 × $0.12 = $2.52 and nothing else is added except postage.

• Billable weight rounds up to the whole gram, like postage — so the figure agrees with the whole grams Bambu Studio shows you.
• There is a $1.00 minimum per part.
• A colour outside the twelve stock spools is priced at a floor of $0.20/g (Flexible TPU keeps its own $0.25/g), because the spool has to be bought in for your order and most of it will go unused.
• Ordering several copies of one part discounts it: 5% off at 5 or more, 10% off at 10 or more.
• Shipping is $7 standard or $15 express in the US, and $30 flat to the 23 international destinations (standard only). Checking out through the cart makes US standard free over $49.50 and international free over $500; Print & Ship adds the postage for the destination you choose, with no free threshold.
• Priority print is $5, or 10% of the items when that is more, once per order if you choose it, beside the shipping choice, and is added to the total as its own row. Normal print is included.

The grams come from a real OrcaSlicer slice wherever one is possible, not from a volume estimate. The estimate reads a part as 30% solid walls plus infill, which undercounts anything thin badly — a stencil that weighed 21 g on the plate estimated at 12.9 g. That is why checkout refuses to sell an unmeasured print: it would sell below the advertised rate. An already-sliced plate is priced from the filament figure in its own header rather than from that estimate.

curl -s https://x3dstudios.com/api/price \
  -H "Content-Type: application/json" \
  -d '{"bboxMm":{"x":120,"y":80,"z":60},"material":"pla","quality":"standard","quantity":1,"color":"Black"}'

{
  "filamentChanges": 0,
  "multiColorGrams": 0,
  "multiColorHours": 0,
  "grams": 320,
  "printHours": 15.84,
  "materialCost": 38.4,
  "machineCost": 0,
  "shipping": 7,
  "baseFee": 0,
  "perUnit": 38.4,
  "subtotal": 38.4,
  "total": 45.4,
  "currency": "USD",
  "material": "pla",
  "quality": "standard",
  "quantity": 1,
  "color": "Black",
  "customColor": false,
  "pricePerGram": 0.12
}

The options you choose#

A project in its own colours#

Upload a Bambu Studio or OrcaSlicer project that assigns two or more filaments and a Project colours card appears: the colours it uses, each with its slot number and material, and a choice between Print in N colours and One colour instead. Colour is selected by default. We slice each plate in its own colours in the background, and the card shows progress such as Slicing plate 2 of 7 with a clock. While that runs the price reads Slicing in colour and the order buttons wait; One colour instead orders straight away.

• When the slice is done the price is what it measured, and colours are counted by what actually prints. Five or more adds the $25 second-AMS fee once for the line, shown as its own row in the price.
• In colour, scale is 100%, quality is standard 0.2mm, infill comes from our profile, and the material is the plastic the project's filaments name. Those controls are locked until you choose One colour instead.
• If colour is not possible (a plate using two filament types, even PLA and PLA-CF, different base plastics on different plates, a colour change at a set layer height, more than eight colours, or only one filament really printing) the card says why and the project is sold in one colour.
• Add to Cart keeps the choice, and the cart and checkout price it from the same slice. Checkout never swaps a colour order for one colour.

Placing the order#

Under the price, choose where it is going (United States or International), the shipping speed, and the print speed. Print & Ship then goes straight to Stripe checkout for that one file. Add to Cart holds it so you can order several files together, and the cart re-prices every print server-side before checkout — the number stored in your browser is never trusted. Either way you get a confirmation email, the order appears on /orders, and it moves through placed, queued, printed, packed, shipped, delivered, with an email at each step after placed.

Troubleshooting#