How do I adjust pile height, reset my tufting machine to factory settings, or diagnose a problem?

octubre 03, 2026

Pile height controls how far the needle pushes through the cloth, which decides how tall your pile will be. It's one of the most common adjustments, and it's often behind other issues too, like a needle that doesn't seem to be working.

To tuft properly, all parts of your machine must stay in sync so the needle and nozzle push the cloth open to create a tuft. Even a few millimeters of misadjustment can throw the machine out of sync. If that happens, an incorrect pile height adjustment is the most likely cause. The good news is that tufting machines are durable, and you can often fix this simply by returning the upper and lower machine bars to their factory settings.

This article covers pile height adjustment, factory settings by model, and a quick diagnosis guide for common machine issues.

Quick Diagnosis Reference

Use this as your first step when diagnosing any machine issue. Find your symptom, try the first check, then see the related article.

• Machine not cutting yarn: Check yarn type, scissors condition and opener adjustment. See Scissors & Cutting Issues.
• Yarn trapped in scissors: Tighten the set screw under the scissors. See Scissors & Cutting Issues.
• Scissors rusty or stiff: Apply 3-in-1 oil to the scissor joints. See Scissors & Cutting Issues.
• High-pitched noise, and oil fixes it: Oil the metal bars around the white/pink bearings straight away. See Sounds & Vibration.
• High-pitched noise, yarn visible in the gear: Remove yarn from the white/pink gear or square bearings. See Sounds & Vibration.
• High-pitched noise, and oil plus the jam check don't fix it: This is likely an electrical issue. Contact support or send the machine in. See Send-In Repair.
• Grinding or rattling sound: Oil the machine and tighten the white cover nuts. See Sounds & Vibration.
• Motor slowing or stopped: Oil first, then check the adapter, then check the cord. See Motor & Power Issues.
• AK-5 power issue: Confirm you're using the original AK-5 adapter only. See Motor & Power Issues.
• Needle bent or broken: Replace the needle and check the pile height gear. See Needle Issues.
• Machine not tufting at all: Check that the pile height gear position is 13–14. See Needle Issues.
• Yarn falling out of the needle: The shutter strip is too far back, so move it forward. See Yarn Tension.
• Yarn breaking at the needle eye: The shutter strip is too far forward, so move it back. See Yarn Tension.
• Cloth showing through the front of the rug: The foot and needle are misaligned. Raise the foot until the needle hole is even with the foot. See Yarn Tension.
• Yarn not staying in the cloth: Push harder against the cloth, and check yarn density and cloth type. See Yarn Tension.
• White gear stuck: Power off, locate the obstruction and oil generously. See White Gear Issues.
• Bolt fell off the machine: Retrieve the nut inside and re-attach it using the gear access procedure. See White Gear Issues.
• Need the factory pile height setting: Duo 52/43mm, AK-I 55/45mm, AK-II 54/53mm. See the factory settings section below.
• Pile height wrong after adjusting: Check the gear hole, and see the pile height sections below.

Machine won't run or feels stuck: the hand-rotation test

If your machine has stopped working, start with this quick test to find out whether the problem is mechanical or electrical:

1. Turn OFF and UNPLUG the machine.
2. Slowly rotate the mechanism by hand through a full 360 degrees.

If it rotates smoothly: the problem is likely electrical. Contact support@tufttheworld.com and we can assess and fix it.

If it is hard to rotate or stops: something is blocking the moving parts. This is not an internal or electrical problem. Keep turning slowly and look for what the moving parts are hitting. Common culprits are bent scissors or a part that has shifted out of place. This is usually an easy fix and often happens with normal use.

Remember to oil your machine every couple of hours of use. If you can't find the obstruction, contact us and we can look at the machine.

Tufting pattern suddenly looks different: check the foot

If your machine suddenly starts producing an uneven or irregular tufting pattern, inspect the foot, as it may be bent. Compare the two sides of the foot. If one is bent, gently bend it back with a pair of pliers so it matches the other. Also check that the machine is cutting cleanly, as poor cutting can cause a similar change.

Before You Adjust: Record Your Machine As It Is

Before you change pile height, swap scissors or make any other adjustment, take lots of photos and measurements of your machine. We also recommend filming yourself as you make the changes. Incorrect changes can stop the machine from tufting correctly, and this record lets you put it back the way it was.

If you'd rather not make the change yourself, we can do it for you or help you over a video call. If you've made several adjustments beyond what the video shows, it's usually best to send the machine in so we can return it to factory settings.

Which DUO Pile Height Version Do You Have?

The DUO comes in low, medium and high pile versions, and the adjustment steps differ by version. To identify yours:

• Gear color: Low pile DUO machines have a pink gear and gear cover.
• Large round gear: Look at the gear at the bottom of the machine. The threaded bar attaches to a numbered hole. If the factory setting is 14mm or 15mm, it's a low pile machine. Medium pile machines are set at 30mm and high pile machines at 40mm.

Not sure? Email a photo of your machine to support@tufttheworld.com, or contact us with your order number or email, and we'll identify it for you.

Changing Pile Height on the DUO

Stay on the side of the gear your machine shipped on

Which side of the gear you use depends on how your machine shipped:

• Shipped at 14mm (even-numbered side): New DUO machines, and all new low-pile models, ship at 14mm. Stay on the even side: 8mm, 10mm, 12mm, 14mm and 16mm. For example, a machine set at 14mm should go down to 8mm, not 9mm.
• Shipped at 15mm (odd-numbered side): Stay on the odd side: 9mm, 11mm, 13mm and 15mm.

If you adjust pile height but the machine behaves the same, check that the bar hasn't been moved to the other side of the gear from the one it shipped on.

Some older quick-start and pile height videos show the change being made on the odd-numbered side. Apart from which side of the gear you use, every step is exactly the same, so follow the video using the positions for your machine. Moving the pivot point to the other side is possible but much more challenging, and it isn't necessary. The machine works across its full range of pile heights, including the lowest setting (8mm).

Videos and manual

Always use the DUO-specific pile height video, not the AK-I version, and pick the video for your specific DUO version. You'll find it, along with the threading and cut/loop switching videos, in our DUO Vimeo showcase. The showcase link and User Manual are emailed to whoever placed the order, and the User Manual also covers pile height. If you received your DUO as a gift, or it arrived without a manual, email support@tufttheworld.com with your machine model and we'll send you the manual and video links.

Don't Adjust the Top Bar Nuts

The nuts on the top bar of your machine should never need adjusting. Don't use pliers on them, because that chews up the nuts and can strip the threads. Make pile height changes with the slider mechanism only, following the video guides shared with your machine. If you're unsure, contact support@tufttheworld.com before adjusting anything.

Replacement slider parts are available in several sizes, so tell us your machine model when you order one.

Factory Settings by Model

If you've changed your pile height and can't remember where you started, these measurements return your machine to its out-of-box setup. Each one is the distance between the two nuts on the upper and lower bars of the pile height mechanism.

Duo machine

• Upper machine bar: 52mm
• Lower machine bar: 43mm

This is the mid-range pile height. The factory setting should not be moved on the Duo.

Medium Pile Duo (2026 machines)

• Upper machine bar: 65mm
• Lower machine bar: 65mm

The 52mm/43mm Duo figures above don't apply to current Medium Pile Duo machines. Older Medium Pile Duo machines may have different factory settings. If you're not sure which you have, measure and photograph both bars before changing anything, then email support@tufttheworld.com for help.

AK-I Cut-pile Machine

• Upper machine bar: 55mm
• Lower machine bar: 45mm

The factory setting is also the tallest pile height on the AK-I, and the tallest factory pile of any model.

AK-II Loop-pile Machine

• Upper machine bar: 54mm
• Lower machine bar: 53mm

The factory setting is also the shortest pile height on the AK-II, and the shortest factory pile of any model.

If your pile height seems extreme, double-check which model you have before adjusting. For step-by-step guidance on adjusting pile height on the AK-I or AK-II, contact us at support@tufttheworld.com or check the video collection that came with your machine.

KRD-I

To change the pile height on the KRD-I, you'll need to extend or shorten the upper machine bar. Contact us at support@tufttheworld.com for step-by-step instructions.

Troubleshooting Pile Height

Pile height measured with a ruler: approximately 20mm (medium pile) off the backing cloth.

• Pile too short or not forming properly: The needle isn't protruding far enough. Adjust the pile height gear upward toward position 14, using the pile height video.
• Pile too tall or floppy: The needle is protruding too far. Adjust the gear downward, and check that your backing cloth is tightly stretched.
• Adjusted pile height but nothing changed: The bar was likely moved to the other side of the gear. Stay on the side your machine shipped on: even (8–16mm) if it shipped at 14mm, odd (9–15mm) if it shipped at 15mm.
• Loose back rows on a low-pile Duo: Low pile settings put more stress on the backing. Make sure the cloth is stretched very tight, and review the pile height section of the manual.
• Pile height pin or bolt came out of position: This can happen from vibration, or if it wasn't fully secured after the last adjustment. Re-seat the bolt in the correct hole using the 'Duo Pile Height' video.

Machine Fires On Its Own (Auto-Firing)

The grounding bars on the sides of the machine are related to your pile height settings. They tell the machine when to stop and return to its home position, so they affect how it behaves after you release the trigger. If your machine keeps running after you let go, or starts firing by itself, the grounding bars have most likely slid out of position.

1. Turn OFF and UNPLUG the machine.
2. Open the grounding bar adjustment video in the Vimeo showcase shared with your purchase.
3. Rotate the grounding bars back to their normal position.
4. Tighten the bolt securely with the Allen key included with your machine.
5. Test the machine and make small adjustments again if needed. It can take a few tries to get the position right.

If the machine still fires on its own after several adjustments, contact support@tufttheworld.com. We can have you send it in and set the grounding bars for you.

Ver artículo completo