# Treadle Reducer ### What It Does Treadle Reducer decreases the number of treadles your draft requires by finding places where pressing two treadles at the same time (a "double-press") can replace a single dedicated treadle. The cloth structure stays exactly the same — you're just using fewer treadles to achieve it. This is especially useful when a draft calls for more treadles than your loom physically has. For example, a pattern that requires 12 treadles might be reduced to 8 by using double-press combinations for some picks.

Treadle Reducer after clicking Run Reduction

*** ### Opening Treadle Reducer * **Ribbon**: Tools tab > Treadle Reducer button *** ### The Treadle Reducer Dialog #### Settings (Left Panel) **Current Treadles** Shows how many treadles your draft currently uses. This is your starting point. **Target Treadles** The maximum number of treadles you want to end up with. Set this to match your loom — if you have 8 treadles, set the target to 8. TempoWeave will try to find a solution that fits within this limit. **Time Limit** How long to let the search run (0.5 to 60 minutes, default 2 minutes). Simple reductions finish quickly, but complex patterns with many treadles may need more time. If the search times out, you can try again with a longer limit or a higher treadle target. **Prefer Single Treadles** When checked (default), the search favors solutions that use single treadle presses where possible, only resorting to double-presses when needed. This produces a more comfortable treadling sequence — fewer picks require pressing two treadles at once. **Use Frequency Weighting** When checked (default), the search gives priority to shaft combinations that appear most often in your treadling. This tends to assign single treadles to the most common picks and double-presses to the rare ones. #### Preview (Right Panel) Shows your original tie-up on the left and the reduced tie-up on the right, side by side. Each cell shows which shafts are connected to which treadle. This updates after the search completes so you can compare before applying. #### Show Mapping After a successful reduction, this button opens a detail view showing exactly how each original shaft combination maps to the new treadles — which picks use a single treadle and which use a double-press. *** ### How to Use It 1. Go to **Tools tab > Treadle Reducer** 2. Set your **Target Treadles** to the number your loom has 3. Adjust the time limit if needed (2 minutes is usually enough) 4. Click **Run Reduction** 5. Wait for the search to complete — a progress indicator shows it's working 6. Review the result message and the preview 7. Click **Apply** if you're happy with the result *** ### Understanding the Results After the search runs, you'll see one of these outcomes: **Success** — The reduction worked. The message shows how many treadles you went from and to (e.g., "12 → 8 treadles"). The preview shows the new tie-up. Click Apply to use it. **No Reduction Possible** — Your draft already uses the minimum number of treadles for its shaft combinations. Every treadle is unique and no double-press combinations can replace any of them. **Timed Out** — The search ran out of time before finding a complete solution. You can: * Increase the time limit and try again * Raise the target treadle count (a less aggressive reduction is easier to find) * Accept a partial result if one was found **Impossible** — The pattern cannot be achieved with your target number of treadles, even with double-presses. You'll need to increase the target. *** ### Step-by-Step Example: Fitting a Draft to Your Loom You have a Summer & Winter draft that uses 14 treadles, but your loom only has 10: 1. Open **Treadle Reducer** from the Tools tab 2. You see "Current Treadles: 14" 3. Set **Target Treadles** to 10 4. Leave the other settings at their defaults 5. Click **Run Reduction** 6. The result shows "Success: 14 → 9 treadles" — even fewer than your target 7. Check the preview to see the new tie-up 8. Click **Apply** Your draft now uses 9 treadles. Some picks will require pressing two treadles at once, but the cloth is identical. *** ### What Changes in Your Draft When you apply a reduction: * **Tie-up** — The columns are reorganized. You'll have fewer treadle columns, and each column represents a "building block" that can be used alone or combined with another. * **Treadling** — Switches to multi-treadle mode. Most picks still use a single treadle, but some picks will show two treadles activated (a double-press). The treadling display reflects this. * **The cloth** — Unchanged. Every pick raises exactly the same shafts as before. *** ### Limitations * **Tie-up mode only** — Treadle Reducer is not available in liftplan mode. Convert to tie-up first (Tools tab > To Tie-up). * **Requires at least 2 treadles** — A draft with a single treadle can't be reduced further. * **Double-press maximum** — The reducer uses combinations of at most two treadles per pick. It won't ask you to press three or more simultaneously. *** ### Tips * **Undo works** — Ctrl+Z (Cmd+Z) reverts the entire reduction in one step. * **Start with the default settings** — The defaults (prefer singles, use frequency weighting) produce the most comfortable treadling for most patterns. Only change them if the default search doesn't find a solution. * **Try a generous target first** — If you're not sure how far the pattern can be reduced, start with a target slightly below your current count. You can always run it again with a lower target. * **Check the mapping** — Use the Show Mapping button to see exactly which picks will need double-presses. If there are too many, try a slightly higher target. * **Pairs well with Treadle Expander** — If you later want to undo a reduction and go back to single-treadle picks, use Treadle Expander to convert double-presses back into dedicated treadles. *** ### Quick Reference | Setting | Default | Range | | ----------------------- | -------------------------- | -------------- | | Target Treadles | Min of current count or 12 | 1–128 | | Time Limit | 2 minutes | 0.5–60 minutes | | Prefer Single Treadles | On | On / Off | | Use Frequency Weighting | On | On / Off |