# Change two dimensions, with a volume limit

> Change several dimensions in one reviewed run and state a measurement the result must meet. If it misses, you can't accept it.

Status: Available · Level: Everyday · About 7 minutes · Canonical: https://paracrux.com/docs/change-two-dimensions-with-a-limit

## You need

- You have done Change a dimension on a copy
- A clean, saved, rebuilt part with one configuration and no equations or external references

## You'll come away with

- Propose up to 16 dimension changes at once
- Set a volume, area or mass limit with its source
- Know what happens when a limit is missed

## Step by step

1. **Capture the part.** In Worksheets, write the brief and choose Capture current part and references.
   Try saying: "Plate 10 to 12 mm thick. Separate block 6 to 8 mm. Keep both solids and their plan sizes."
2. **Propose both changes.** Enter the first change, then use Additional dimension changes (up to 16 total) for the rest. Each must be a captured driving dimension, with a new positive value that differs from the old one.
3. **Add a measurement limit.** Under Required measurement limits, tick volume, area or mass. Enter a Minimum and a Maximum, and where the requirement comes from. Each measurement can be used once.
4. **Run it and read the limit.** Choose Save proposal for review, then Accept plan and execute on copy. The limit is checked after the rebuild and again after the native reopen, and marked pass, fail or unproven.
5. **Accept only a pass.** If every limit passes and the independent STEP check agrees, write your note and choose Accept result. Anything else fails the run, and acceptance is refused.

## Walkthrough

The part, both changes and the 32,000 mm³ result are from a recorded run on 23 September 2026. The limit values and the failing case are examples, labelled as such.

- **Captured:** Body 1 = 60 × 40 mm plate, 10 mm thick; Body 2 = 20 × 20 mm block, 6 mm thick; Volume before = 26,400 mm³
- *24,000 + 2,400 = 26,400 mm³.*
- Provenance: recorded

- **Proposal:** Plate thickness = 10 → 12 mm; Block thickness = 6 → 8 mm; Expected volume = 28,800 + 3,200 = 32,000 mm³
- Provenance: calculated

- **Required measurement limit:** Volume = 31,990 to 32,010 mm³; Source = Analytic prism dimensions
- **Gate:** Save the proposal for review. Nothing runs until you accept execution.
- Provenance: illustrative

- **Run on a copy:** After rebuild = 32,000 mm³ · pass; After native reopen = 32,000 mm³ · pass; STEP check = 2 solids · 32,000 mm³; Original = unchanged
- Provenance: recorded

- **What a miss looks like:** Volume = 31,200 mm³ · fail; Run = failed; Accept result = refused
- *If the block had been left at 6 mm, the result would be 31,200 mm³. That fails the limit, the run is marked failed, and Accept result is refused: 'Verification evidence does not permit acceptance'.*
- Provenance: calculated

## What it won't do

- At most three limits, one each for volume, area and mass. Both bounds and a source are required.
- Limits are optional. Without one, the run checks the dimensions and the STEP import only.
- A limit shows the result meets a number you chose, not that the number is right.

## Covers

- Reviewed dimension changes (Available): Pick up to 16 driving dimensions, set new values, run the change on a copy and check the outputs before you accept. Where: In the app, Worksheets tab

## Next

- [Decide what the Agent can send](https://paracrux.com/docs/share-design-context.md): Design context stays on your computer until you allow it. See what goes, choose where it is processed, and switch it off again.