# Treadle Expander

### What It Does

Treadle Expander is the opposite of Treadle Reducer. It eliminates double-press treadle combinations by giving each unique shaft pattern its own dedicated treadle. After expanding, every pick in your treadling uses exactly one treadle — no more pressing two at once.

This is useful when you've been working with a reduced treadle set (using double-presses) and now want to move to a loom with more treadles, or when you simply prefer the simplicity of one treadle per pick.

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### Opening Treadle Expander

* **Ribbon**: Tools tab > Treadle Expander button

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### The Treadle Expander Dialog

#### Analysis (Left Panel)

When the dialog opens, it automatically analyzes your draft and shows:

**Current Treadles** How many treadles your draft currently uses.

**Multi-Treadle Picks** How many picks in your treadling currently require pressing more than one treadle simultaneously. If this is zero, there's nothing to expand — every pick already uses a single treadle.

**Unique Lift Patterns** The total number of distinct shaft combinations across all your picks. This is how many treadles you'll need after expanding — one for each unique pattern.

**Max Treadles** The maximum number of treadles allowed (up to 128). If your unique lift patterns exceed this, you won't be able to expand. In practice, this is rarely a concern.

#### Preview (Right Panel)

Shows your original tie-up and the expanded tie-up side by side. The expanded tie-up will have one column per unique shaft combination. This updates after you click Expand.

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### How to Use It

1. Go to **Tools tab > Treadle Expander**
2. Review the analysis — check how many multi-treadle picks exist and how many unique lift patterns there are
3. Click **Expand Treadles**
4. Review the result and the preview
5. Click **Apply** if you're happy with it

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### Understanding the Results

After clicking Expand, you'll see one of these outcomes:

**Expanded (more treadles)** — The most common result. Your treadle count increases to accommodate all the unique shaft patterns, and every pick now uses a single treadle. For example, "8 → 12 treadles."

**Expanded (same count)** — Your treadle count stayed the same, but multi-treadle picks were eliminated. This happens when the double-press combinations happened to match existing treadle patterns.

**Optimized (fewer treadles)** — Occasionally, expanding actually reduces your treadle count. This can happen when your original draft had redundant treadles — different treadles that raised the same shaft combinations.

**Exceeds maximum** — The pattern requires more treadles than the maximum allows. This is rare, but it means the draft has too many unique shaft combinations to fit in single-treadle mode.

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### Step-by-Step Example: Preparing for a Larger Loom

You've been weaving a pattern on an 8-treadle loom using double-presses. Now you're moving to a 16-treadle loom and want to simplify the treadling:

1. Open **Treadle Expander** from the Tools tab
2. You see "Current Treadles: 8" and "Multi-Treadle Picks: 45" and "Unique Lift Patterns: 12"
3. Click **Expand Treadles**
4. The result shows "Expanded: 8 → 12 treadles (all multi-treadle picks eliminated)"
5. Your 16-treadle loom can handle 12, so click **Apply**

Every pick now uses a single treadle. The treadling is easier to follow and you never have to press two at once.

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### What Changes in Your Draft

When you apply an expansion:

* **Tie-up** — Each unique shaft combination gets its own treadle column. The tie-up may have more columns than before, but each one maps to exactly one lift pattern.
* **Treadling** — Switches from multi-treadle mode to single-treadle mode. Every pick shows exactly one treadle.
* **The cloth** — Unchanged. The same shafts rise on the same picks, producing identical fabric.

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### Limitations

* **Tie-up mode only** — Treadle Expander is not available in liftplan mode. Convert to tie-up first (Tools tab > To Tie-up).
* **Requires multi-treadle picks** — If your draft already uses single treadles for every pick, there's nothing to expand. The dialog will let you know.

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### Tips

* **Undo works** — Ctrl+Z (Cmd+Z) reverts the expansion in one step.
* **Check the count first** — The "Unique Lift Patterns" number tells you exactly how many treadles you'll need. Make sure your loom can accommodate that many before expanding.
* **Pairs with Treadle Reducer** — Reducer and Expander are complementary tools. Reduce when you need fewer treadles (accepting double-presses), expand when you have enough treadles and prefer single presses. You can go back and forth freely.
* **After importing** — Some imported WIF files use multi-treadle notation. If you prefer single-treadle picks, Treadle Expander is a quick way to convert them.

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### Quick Reference

| Detail        | Info                                                          |
| ------------- | ------------------------------------------------------------- |
| Location      | Tools tab > Treadle Expander                                  |
| Works in      | Tie-up mode only (not liftplan)                               |
| Input         | Draft with multi-treadle picks (double-presses)               |
| Output        | One treadle per unique shaft combination, single presses only |
| Treadle count | May increase, stay the same, or occasionally decrease         |
| Cloth         | Unchanged — identical before and after                        |