Printing a batch: how many fit and how long it takes

By Tiehl Roberto Matías · 7 min read · Updated 26 October 2026

Leer en español

Printing twenty pieces at once does not save a gram of filament, but it completely changes what it costs you: one setup, one pause and one go at peeling the plate. In exchange there is a condition almost nobody sees coming, and breaking it ruins the whole batch.

How many pieces fit

This table counts how many pieces fit leaving 5 mm between pieces and 5 mm of margin against the edge of the bed, which is the prudent amount: packed together they peel each other off, and against the edge you risk the head not reaching. The pieces count at their real size, not the code's: the 40 mm keychain is 48 long with its tab, and the 90 mm plate is 95 with the strip holding the hole.

Before a big batch it is worth knowing your printer's real limit, not the one from the general rule. That is what the test kit is for: six pieces, thirty-five grams and one afternoon less of guessing.

Piece	A1 mini (180)	Ender 3 / MK4 (220)	A1 / P1S (256)	300 bed
Keychain 40 mm	9	16	20	30
Card 85 × 55 mm	2	6	8	12
Desk stand 70 mm	8	10	18	21
Plate 90 mm	1	4	4	6
Plate 120 mm	1	1	2	4

Look at the jump between beds: from an A1 mini to an A1 there is not 40 % more room, there is more than twice the pieces, because area grows with the square of the side. And look at the large plates too: on a 256 mm bed only two 120 mm plates fit, because two rows of 124 mm no longer go in. A batch of plates is always going to be a short one.

What a plate weighs and how long it takes

With the weights this site's own engine calculates, a full plate on a 256 mm bed comes out like this:

Batch	Units	Filament	Approximate time
Keychain 40 mm	20	122 g	~6 h
Plate 90 mm	4	110 g	~5 h
Desk stand 70 mm	18	587 g	~27 h

The times come from the same sum as the cost guide (in Spanish): about 6 mm³ a second, which is a cautious figure for a 0.4 nozzle. Your slicer will give you another number and its number is the one that counts.

What matters in this table is not the total, it is the comparison: printing 20 keychains together takes the same time as printing them one by one, because the plastic is the same. What changes is your time. One at a time means 20 setups, 20 colour-change pauses and 20 goes at peeling the plate. Together, one of each.

The pause: one for all of them

Here is the real reason batches pay off with these pieces.

If you print in two colours with a single extruder, the trick is to stop the print at the height where the base ends and change filament. It is explained step by step in the colour change guide.

And the machine prints layer by layer, the whole plate at once. That means that when it reaches the change height, it is at that height on all 20 pieces at the same time. One pause, one spool change, and all 20 come out in two colours.

One at a time, the same work is 20 pauses spread over several days, each one forcing you to be near the machine at a particular moment. That is the real difference, and it is enormous.

The condition you have to meet

For that single pause to work, every piece on the plate has to have its colour change at exactly the same height. And that is not automatic.

The change happens where the base ends and the relief begins. If you mix pieces with different bases on the plate, the pause will only be right for some and the rest come out in one colour or with the code half done. It is a failure you do not see until the batch is finished.

The two rules that prevent it:

• One base height per plate. If the generator gives you 3 mm of base for all of them, perfect. If you change the base thickness on one, that one goes in another batch.
• Careful mixing piece types. The desk stand is angled and has a foot, so its code does not start at the same height as a flat plate's. Plates with plates, keychains with keychains, stands with stands.

There is a second trap, on the slicer side: do not turn on sequential object printing. That option, which in Bambu Studio and Orca appears as printing «by object», finishes each piece completely before starting the next. It sounds good, but it breaks the single-pause trick — it is 20 pauses again — and it also forces the head to pass over finished pieces, with the risk of catching them. For batches of these pieces, layer by layer.

When every piece carries a different code

This is the case with table numbers in a restaurant, or a run of keychains with one link per customer. Here duplicating a piece in the slicer will not do: each code is a different object.

The route that works:

1. Generate and download one file per code, with a name you will recognise later: table-01, table-02. It is worth being tidy here, because on the plate all the pieces look very alike.
2. Import them all together into the slicer and let them arrange themselves with the auto-arrange function.
3. Check in the preview that each piece's number is what you think. This is the moment to catch a repeated file or a missing one.
4. Separate them as you collect them. Twenty nearly identical pieces get mixed up in thirty seconds on a table.

Before any of this, and it sounds obvious but it is where people come unstuck: scan one of the generated codes, not all of them, but one. If you got the link pattern wrong, the mistake is in all twenty. The full protocol is in the testing guide.

The risk of putting everything on one plate

A big batch concentrates the risk. If at hour five one piece comes loose, the head drags it and can knock over the ones next to it, or end up with a blob stuck to the nozzle. What on a single piece is twenty minutes lost, on a full plate is the afternoon and the material.

Three things that reduce it a lot:

• The first batch, half a plate. The first time you make a new piece, put six on instead of twenty. If something goes wrong you lose little; if it goes well, you know the configuration holds.
• A brim on small pieces. A keychain has little area stuck to the bed and is the one that comes loose most. A few millimetres of extra edge hold it down and come off with a fingernail.
• Leave the purge area clear. Nearly every machine cleans the nozzle at a fixed spot on the bed. Put a piece there and the batch starts badly.

And a recommendation about handing them out: when the batch comes off, scan two or three pieces at random, not just the first. Pieces at the edge of the plate do not always come out the same as the ones in the middle, and it is better that you find out than the customer.