Calibration how-to

This article shows you how to fit Quotometry’s estimates to your own machines, using parts you have already made. Some numbers in a pricing model cannot be known from outside your shop: how much of a print is travel rather than extrusion, how densely your nesting really packs a build, how much resin actually cures inside a support. Quotometry marks those settings calibratable, gives them honest defaults, and lets you replace the defaults with your own data.

Before you begin

You need three or more parts you have actually made on the machine you are calibrating, and for each one at least one of:

• the real machine time, as the machine or slicer reported it, in minutes. Leave out bed heating, queueing and the twenty minutes it sat waiting for someone to collect it;
• the real mass of the printed part, in grams, from a scale.

Three is the minimum. Five to eight is better, and variety matters more than number: a tall part, a flat one, a dense one and a hollow one constrain the model far more than eight versions of the same bracket.

Calibrate a machine

1. Open the configuration and go to its Calibration section.
2. Choose the machine.
3. Add each reference part (Add a part), with how many you made, its machine time in minutes and its mass in grams.
4. Choose See what it would change. Quotometry adjusts the calibratable coefficients within their allowed range and shows the typical error before and after, as a percentage.
5. Check what it wants to change: every coefficient, with its current value and its fitted one.
6. If you are happy, choose Apply to the draft.

Read the result

The error shown is the typical relative error: roughly, “how far out we are, usually”. Most shops start somewhere between 15 % and 25 % and end in single digits.

The fit works on relative error on purpose, so a two-minute part and a two-day part count equally. A model that is right about long jobs and wrong about short ones loses money on the jobs you get most of.

If the fit barely improves

Two causes account for nearly all of it.

Your reference parts are too similar. Three near-identical parts tell the fit almost nothing. Add something shaped differently.

Your recorded times include something the model does not. If the “print time” in your notes includes warm-up or waiting, the fit absorbs it into a coefficient and makes everything else slightly wrong. Use the machine’s own number.

If it refuses or warns

Message	What it means	What to do
Not enough references	Fewer parts or measurements than a fit needs.	Add parts until you have at least three with a time or a mass.
Nothing to calibrate	This machine’s process has no calibratable settings.	Nothing: the defaults are all there is to adjust.
Cannot estimate	The draft does not compile, the machine does not exist, or it cannot make one of the reference parts.	Fix the draft’s errors, or remove a part that does not fit the machine.
A coefficient is pinned at its limit	Your measurements disagree with the model in a way calibration cannot fix.	Check for a wrong figure, such as grams typed as kilograms, or a time that includes waiting.
No improvement	The best fit is no better than your current settings.	Nothing to apply: your settings already match these parts.

When to calibrate again

Whenever your shop changes: new firmware, new slicer settings, a different filament brand, a new machine. It takes minutes because the data is your own job history, and it is the single biggest improvement available to most shops’ quoting accuracy.

What calibration never touches

Anything you know exactly. The price of your filament, your hourly rate and your margin are facts about your business, not uncertainties about your machine, and the fit is not allowed near them.

Next steps

• Simulator and golden parts: check the result against prices you know are right.
• Drafts, versions and publishing: publish the calibrated draft.
• Your first configuration: the settings worth getting right first.