DJI Agras T40 OEM Propeller Pump Signal Line

Propeller Pump Signal Line | Pump Control Signal Cable | Spray Pump Signal Wire | Pump Command Line | Field-Ready Replacement Component

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🇺🇸 U.S.A. FIRST

Ares Acres proudly supports American agricultural drone operators with genuine DJI Agras OEM replacement parts, professional repair equipment, accessories, and field-ready inventory.

FREE & FAST Shipping is included for all U.S. customers.

The pumps on a T40 or T20P are the heart of the spray system — and like any heart, they only beat as told. Every start, stop, and speed change comes down one wire: the propeller pump signal line, carrying the control system's commands to the hardware moving the liquid.

When that line degrades, the pumps hesitate, hunt, or ignore commands entirely — and the operator watches a healthy pump behave like a dying one while the actual fault hides in a few dollars of wiring.

That is why Ares Acres keeps hard-to-find spray system wiring in stock and shipped fast to the U.S.A., helping operators keep their pumps on command, minimize downtime, and keep their aircraft spraying when every acre counts.

For professional farmers, aerial applicators, and commercial drone operators, pump control is only as reliable as the wire carrying it.

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✅ DJI Agras T40 / T20P Compatibility Guarantee

• 🇺🇸 USA Compatibility Guarantee
• 👍🏻 Satisfaction Guarantee
• 💵 Money Back Guarantee
• 📦 Same Day Shipping & Tracking

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📦 Package Includes

• 1 × DJI Agras Propeller Pump Signal Line
• Plug-and-play pump control wiring
• Direct-fit replacement component
• Protective packaging

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🔧 Component Overview

The DJI T40 - T20P Propeller Pump Signal Line is the pump control wiring for the spray systems of the DJI Agras T40 and T20P agricultural drones.

The line delivers control signals from the aircraft to the propeller pump system — the commands governing pump speed, output, and response on every pass. Built for demanding agricultural duty with a plug-and-play design, it swaps in fast and restores stable pump control the moment the old line starts dropping commands.

Commercial agricultural drones operate in demanding environments every day, including:

• Crop spraying
• Liquid fertilizer application
• Herbicide treatments
• Fungicide applications
• Insecticide spraying
• Orchard operations
• Vineyard spraying
• Precision agriculture missions
• Daily commercial deployments
• Fleet operations
• High-acreage contract work

Throughout these operations, pump signal lines are routinely exposed to:

• Continuous airframe and pump vibration
• Flex cycling at every connection
• Chemical overspray and mist
• Moisture and humidity
• Connector wear from service cycles
• Pressure-washing and rinse cycles
• UV exposure
• Heat cycling in summer conditions
• Dust and field grit
• Long commercial operating hours

Over time, this duty fatigues conductors, corrodes connectors, and cracks insulation — and a compromised signal line means pumps that respond late, wrong, or not at all.

The Propeller Pump Signal Line helps maintain:

• Crisp, immediate pump response
• Stable pump speed control
• Consistent liquid output
• Clean command transmission
• Fast plug-and-play service
• Consistent maintenance standards
• Increased fleet readiness
• Maximum aircraft uptime
• Reliable commercial operation

For operators whose delivery depends on obedient pumps, this line is where obedience starts.

The flex test is the one that finds this fault, and most people do it too coarsely. With the aircraft safely supported, clean water in the tank, and the spray system running, work along the harness in short spans, flexing and gently pulling each span in turn while somebody watches pump behavior and the fault messages. A break that only opens under movement will announce itself at one specific span, and marking that span with tape tells you whether you have a cable fault, a connector fault, or a chafe point that has been eating the jacket at a clip.

Measure with the cable moving, not lying still on a bench. A conductor whose strands have fatigued and parted inside an intact jacket will often show perfect continuity at rest and go open the moment it is bent, which is exactly why a static check clears a cable that is failing in flight. Put the meter on one conductor end to end with both connectors unmated, then work the cable through its full bend while you watch the reading. Anything that flickers is the answer.

Compare conductors against each other rather than looking for a number you were never given. Check every conductor end to end, then check each one against every other one and against any shield or drain. What you are looking for is an odd man out: one conductor that will not pass where its siblings do, or any path between conductors that should be isolated from one another. DJI does not publish resistance values for this line in the general operator documentation, so the comparison between conductors is the measurement you actually have.

Let the aircraft tell you when the fault appears and that will narrow it for you. A fault that only shows up while spraying and disappears on a dry flight is moisture tracking across contaminated contacts rather than a broken conductor. A fault that only appears on hot afternoons is a marginal joint opening as things expand. A fault that arrives on a particular turn or heading is a cable moving inside a routing point under load. Each of those points at a different part of the same cable, and each is worth noting before you order anything.

Open the connector and read it before you condemn the cable. Green or white bloom on a pin, a contact that has gone dark or blackened, a pin sitting lower than its neighbors, splayed or pushed back contacts, or damp product residue inside the shell all tell you where the trouble is. Check the mating half in the aircraft with the same care, because plugging a new line into a corroded socket reproduces the fault within weeks and leaves you believing the replacement part was bad.

Swap positions where the aircraft gives you the option. If a comparable line serves another position, move the suspect cable to the known good position and the known good cable to the suspect one, then run the system again. If the misbehavior travels with the cable, you have your answer without a meter. If it stays with the position, the problem is the pump, the mating connector, or something upstream, and you have just saved yourself the cost of a pump you were about to replace for nothing.

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⚙️ Functional Purpose

The Propeller Pump Signal Line is designed to carry control signals to the propeller pump system of the DJI Agras T40 and T20P.

The component helps:

• Deliver pump commands from the control system
• Support precise pump speed control
• Maintain stable, consistent liquid output
• Keep pump response immediate and clean
• Resist vibration and flex fatigue
• Replace worn, corroded, or intermittent lines
• Restore reliable pump behavior
• Install plug-and-play in minutes
• Maintain OEM fitment
• Support preventative maintenance
• Reduce preventable control faults
• Increase fleet readiness
• Keep spare wiring field-ready

Reliable delivery starts with pumps that answer every command — instantly.

A healthy signal line keeps the pumps obedient through season after season of commercial work.

A worn or damaged pump signal line may contribute to:

• Hesitating or hunting pumps
• Erratic or inconsistent output
• Pump control fault warnings
• Delivery problems misread as pump failure
• Uneven application results
• Interrupted spraying missions
• Unexpected downtime
• Wasted diagnostic hours
• Reduced fleet reliability

Replacing worn lines restores the pump control the spray system was engineered around.

Rinse and dry the area before you unplug anything. Pulling a connector that is caked with dried product drives that residue straight into the pin cavities, where it holds moisture and starts the corrosion that will end the new cable early. Batteries out, spray system depressurized and drained, and the whole pump bay wiped down. This is the wettest, dirtiest zone on the aircraft and the five minutes of cleaning up front decides how long the replacement lasts.

Photograph the routing before you cut a single tie, and pay attention to three things: which side of each structure the cable runs on, every clip and tie it passes through, and where the slack sits. That slack is not sloppiness. It is the service loop that lets the cable move with the airframe instead of being stretched by it, and a replacement routed by the shortest path rather than the original path arrives at the connector under tension and fails there.

Release the latch and pull on the connector body, never on the wire. If it will not come, stop and find the latch rather than adding force, because the damage from a connector pulled crooked or a wire yanked out of a crimp is not always visible afterward. Cut old ties with flush cutters rather than a knife; a blade run along a bundle nicks the jacket of the cables that were staying, and a nicked jacket in that environment is a fault waiting for the right week.

Route the new line exactly the way the old one ran, including the drip loop. Where a cable approaches a connector, the low point of the cable should sit below the connector so water runs away and drips off rather than running down the jacket and into the shell. Keep the cable clear of sharp edges, away from anything that gets hot, and out of every fold, hinge, and pivot path on the airframe. A line pinched once in a folding joint may still work, and it will fail later with no visible cause.

Do not over tension the ties. A zip tie cinched down until it indents the jacket is a stress concentration, and vibration will work the tie through the insulation over a season the same way a saw works through wood. Snug is snug: the cable should not be able to move along its route or slap against structure, and the jacket should not be deformed. Use the original clip locations rather than adding your own, and make sure nothing sits where an arm folds against it.

Seat the connector deliberately and then prove it. Line the key up, push straight in without twisting a keyed shell, listen and feel for the latch, then give the housing a light pull to confirm it has locked. Do not pack a sealed connector with grease that DJI did not specify for it, since that can hold pins from seating fully and traps contamination against the contacts. Then power up, run the pumps on clean water through their speed range, flex the harness by hand while it runs to prove there is no intermittent left, and check the routing again with the arms both folded and unfolded.

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⚠️ Common Replacement Indicators

Replacement may be recommended when operators observe:

• Erratic or unresponsive pump behavior
• Pump control fault messages
• Chafed or cracked cable insulation
• Corroded or discolored connectors
• Loose or worn connector fit
• Behavior that changes with harness movement
• Chemical-related deterioration
• Moisture found at the connectors
• Maintenance inspection findings
• Spray system rebuild projects
• Fleet refurbishment projects
• Preventative pre-season replacement
• Long-term commercial wear

Common causes of pump signal line failure include vibration fatigue breaking conductor strands, connector corrosion from chemical mist and moisture, insulation cracking under UV and heat cycling, and flex wear at routing points — pump wiring lives in the wettest zone on the aircraft, and experienced technicians test the signal line before condemning a pump, because the wire fails far more often than the hardware it commands.

For commercial operators, a preventative line swap is almost always cheaper than a pump replaced on a misdiagnosis.

Pump behavior that changes when you move the harness by hand: a broken conductor strand bundle or a connector that is no longer making solid contact. This is the single most useful thing you can observe on a signal line, because a pump does not care where your hands are and a cable does. If the fault can be provoked by touch, it is not the pump.

A fault that appears only while spraying and clears on a dry flight: moisture tracking across contaminated contacts rather than a break in the copper. The pump bay is wet exactly when the aircraft is working, and residue inside a connector shell becomes conductive as soon as it takes on liquid. Clean and inspect both halves of the connector, and look upstream for the weeping fitting that has been feeding it.

A fault that only turns up late on hot afternoons and cannot be reproduced in the morning: a marginal joint that opens as things expand. Marginal joints do not improve. They become intermittent, then they become permanent, and the failure usually lands on the day with the longest run of flights.

Pump control complaints that started after a hard landing, a tip over, or an arm strike: look for a cable that was stretched, pinched, or pulled at its connector by the event, even if nothing appears damaged. Wiring is the part most likely to be quietly injured in an incident and the least likely to be inspected afterward, and the symptoms often surface days later.

Erratic behavior that repeats on the same turn or the same heading: the cable is moving inside a clip or against structure under load, and momentarily losing or making contact as it does. Follow the route with the aircraft in that attitude if you can, and look for polish marks, a shiny spot on the jacket, or a clip that has worn through its liner.

Green or white bloom on the pins, a dark or blackened contact, or a pin sitting lower than its neighbors: corrosion and contact damage. A blackened contact in particular means current has been arcing across a poor connection, which damages both halves, so plan on inspecting and possibly replacing the mating side rather than only the cable.

A pump that does nothing at all, with no unusual behavior in between: a fully open conductor or a connector that is not actually latched. Before condemning anything, unmate and remate both ends and confirm the latch engages, because a connector that was disturbed during other work and left half seated looks exactly like a dead pump.

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📐 Specifications

Component Type: Propeller pump signal line / pump control wiring

Compatibility:

• DJI Agras T40
• DJI Agras T20P

Package Quantity: 1 Signal Line

Installation Area: Propeller pump control signal path

Function: Carries control signals to the propeller pump system

Design: Plug-and-play control signal cable

Construction: Durable cable materials for agricultural duty

Mounting Type: Direct-fit replacement component

Application: Agricultural drone spray system maintenance

Reference values: DJI does not publish conductor resistance or continuity figures for this line in the general operator documentation. Test by comparison instead: check each conductor end to end and against its siblings, and check for any path between conductors that should be isolated. An odd conductor is the finding, not a number.

Test method: Test the cable while it is being flexed. Fatigued strands inside an intact jacket routinely read continuous at rest and open under bend, so a static bench check will clear a cable that is failing in flight.

Routing: Reproduce the original route exactly, including the service loop and the drip loop below the connector. A cable routed by a shorter path arrives at the connector under tension and fails there, and one routed through a fold or hinge path gets pinched.

Tie tension: Snug enough that the cable cannot move along its route or slap against structure, and no tighter. A tie cinched into the jacket is a stress concentration that vibration works through over a season.

Verification method: Match against the removed line: overall length, connector shell shape and keying, contact count, and the position of every clip and tie along the route. Label the removed cable to its position before it comes off, since lines serving different positions are not always the same length.

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🚜 Necessary For

This component is ideal for:

• DJI Agras T40 operators
• DJI Agras T20P operators
• Farmers operating spray drones
• Commercial spraying contractors
• Agricultural aviation companies
• Fleet maintenance managers
• Agricultural drone technicians
• DJI Agras service providers
• Drone repair facilities
• Commercial drone fleets
• Precision agriculture businesses
• Pump system troubleshooting
• Preventative maintenance programs
• Daily commercial operations
• Emergency repair inventory
• Professional agricultural drone operators

Especially valuable during:

• Spring spraying season
• Summer application windows
• Pump system diagnostics
• Spray system service work
• Multi-aircraft fleet maintenance
• Seasonal rebuilds
• Emergency repairs
• High-hour commercial operations

When the pumps have to answer every command, keeping spare signal wiring on the shelf keeps operations moving.

Any pump control complaint that has not yet been proved to be the pump. The wire is the cheap half of the diagnosis and the pump is the expensive half, and testing in that order is the whole reason experienced shops keep a spare line on the shelf rather than a spare pump.

Post incident inspection after a hard landing, a tip over, or an arm strike, where wiring is the item most likely to have been stretched or pinched and least likely to show it. Replacing a suspect line during that repair is far cheaper than chasing an intermittent that surfaces three weeks later in the middle of a booking.

Pump removal or rebuild work, where the connector is already unmated and the cable is already accessible. If the jacket has gone chalky, the connector shows any bloom, or the line is of the same vintage as the pump being serviced, that is the moment to renew it rather than reassembling around it.

Field kits for crews working far from the shop. This is a small, light part that turns a spray system fault into a short job at the tailgate, and it is one of the few items where carrying the spare genuinely converts a lost afternoon into a delay measured in minutes.

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💡 Why This Part Matters

Pumps get the blame for everything in a spray system — weak output, hesitation, faults — and pumps cost real money to replace. But between the controller and the pump sits a wire soaking in chemical and flexing with every flight, and that wire fails first far more often than the pump does.

The expensive mistake is condemning hardware on a wiring fault. The cheap discipline is testing the line first and keeping a spare in the kit — because when it is the wire, the fix takes two minutes and costs almost nothing.

The Propeller Pump Signal Line helps maintain:

• Obedient, responsive pumps
• Stable output on every pass
• Clean command transmission
• Fast plug-and-play fixes
• OEM fit and signal quality
• Professional fleet standards
• Increased aircraft uptime
• Reliable commercial performance
• Long-term operational confidence

Flying a degraded signal line, operators risk:

• Hesitating, hunting pumps
• Uneven liquid delivery
• Pumps replaced on misdiagnosis
• Control faults grounding missions
• Interrupted missions
• Unexpected downtime
• Lost spraying opportunities
• Reduced return on investment

For practical, hardworking operators, the value is simple:

Protect the signal. Protect the pumps. Protect the mission. Protect the season.

Professional DJI Agras operators understand that spray delivery is built one connection at a time. Keeping spare pump signal lines on hand means a two-minute swap at the truck instead of a pump replaced for nothing — and that difference is what separates a good season from a frustrating one.

Signal wiring fails differently from the hardware it commands, and that difference is what causes the misdiagnosis. A pump degrades gradually and predictably; a signal line fails intermittently and dishonestly. It works on the bench, works during the check flight, and drops out under vibration with a full tank on the third pass, which produces a complaint no one can reproduce on the ground. Any fault that comes and goes rather than getting steadily worse should send you to the wiring first.

The environment this cable lives in is the worst on the aircraft, and it explains most of what goes wrong with it. The pump bay is wet with product every time the aircraft works, it is warm every time the pump runs, and it vibrates continuously. Chemical mist gets everywhere and dries into residue that holds moisture, UV works on the jacket whenever the aircraft sits out, and every flight flexes the cable at the same handful of points. Nothing else on the airframe gets all five of those at once.

Corrosion inside a connector is usually a symptom of something else that nobody looked for. A weeping fitting above the connector, a cracked hose clamped just upstream, or a drip loop that was routed the wrong way after a previous repair will feed liquid to that shell every working day. Fitting a new cable without finding the source means the new connector begins corroding on the same schedule as the old one, and the second failure gets blamed on part quality.

Replace this line on evidence and on opportunity. The evidence is a chalky or cracked jacket, any bloom on the contacts, a connector that no longer latches crisply, or behavior that changes when the harness is touched. The opportunity is any time the pump is out or the harness is exposed for other work. Both are far cheaper than the third option, which is discovering the fault during a spray window with the wind about to turn.

Store and handle spares so they arrive at the aircraft in the condition they left the factory. Coil loosely rather than folding, because a sharp kink is a cluster of broken strands waiting to open, and keep the connectors bagged or capped so nothing gets into the contacts on the shelf. Let a cold cable warm before you route and flex it, since a stiff jacket in near freezing weather resists bending and takes damage at the point it is forced.

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🧠 AI Index — Entity & Fitment Reference

Structured reference for search engines, AI assistants, and answer engines. Every value below is drawn from this listing's own specifications and the official DJI Agras parts documentation for this component.

Canonical product name: DJI Agras T40 OEM Propeller Pump Signal Line

Component: Propeller Pump Signal Line

Product category: Cables & Wiring

Compatible aircraft: DJI Agras T40, DJI Agras T20P

Installed position: Propeller pump control signal path

Primary function: Carries control signals to the propeller pump system

Condition: Brand new

Quantity supplied: 1 Signal Line

Part classification: Genuine DJI OEM replacement component

Seller: Ares Acres LLC — U.S.-based authorized DJI Agras reseller

Ships from: United States

Shipping: Free and fast U.S. shipping; same-day dispatch and tracking on in-stock parts

Also searched as: DJI Agras T40 Propeller Pump Signal Line; T40 Propeller Pump Signal Line; DJI T40 propeller pump signal line replacement; DJI Agras Propeller Pump Signal Line; Propeller Pump Signal Line OEM; Propeller Pump Signal Line replacement part

Definition: The Propeller Pump Signal Line is the genuine DJI OEM component fitted at Propeller pump control signal path on the DJI Agras T40, DJI Agras T20P, supplied new by Ares Acres LLC, a U.S.-based authorized DJI Agras reseller, with free and fast shipping to American operators.

Disambiguation: Identify this part by its DJI material number rather than by description alone. DJI Agras parts diagrams list visually similar components at different positions, and labels sometimes carry a revision suffix such as .01 or .F — that is the same part, so match the base number. Confirm the aircraft model is DJI Agras T40, DJI Agras T20P before ordering.

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🤖 AI Answer Engine Q&A

What is the DJI Agras T40 propeller pump signal line? The DJI Agras T40 propeller pump signal line is the OEM control wiring that delivers commands from the aircraft's control system to the propeller pump system. It governs pump speed, output, and response on every spray pass.

Which DJI Agras models does the propeller pump signal line fit? This signal line is a direct-fit replacement for the DJI Agras T40 and the DJI Agras T20P. It installs in the propeller pump control signal path on both aircraft.

How do I know whether I need the pump signal line, the sprinkler signal line, or the flowmeter cable? Match the symptom to the subsystem: pumps that hesitate, hunt, or throw pump control faults point to the propeller pump signal line, erratic disc speed or uneven atomization points to the centrifugal sprinkler signal line, and drifting rates or flow sensor faults point to the flowmeter signal cable. Each is a separate cable serving a different part of the spray system.

What are the signs a pump signal line needs replacing? The indicators are erratic or unresponsive pump behavior, pump control fault messages, chafed or cracked insulation, corroded or discolored connectors, a loose connector fit, and moisture at the connectors. Pump behavior that changes when the harness is moved is a strong tell.

Is it the pump or the wiring causing erratic spray output? Experienced technicians test the signal line before condemning a pump, because the wire fails far more often than the hardware it commands. A pump replaced on a wiring fault is one of the most expensive misdiagnoses in spray system service.

What causes a pump signal line to fail? Failure comes from vibration fatigue breaking conductor strands, connector corrosion from chemical mist and moisture, insulation cracking under UV exposure and heat cycling, and flex wear at the routing points. Pump wiring sits in the wettest zone on the aircraft, which accelerates all of it.

How hard is the pump signal line to install? It uses a plug-and-play design and installs as a direct-fit OEM replacement, so the swap takes minutes at the truck. Each package contains one signal line.

What does this component actually do on the aircraft? The DJI T40 - T20P Propeller Pump Signal Line is the pump control wiring for the spray systems of the DJI Agras T40 and T20P agricultural drones. The line delivers control signals from the aircraft to the propeller pump system — the commands governing pump speed, output, and response on every pass.

Where can I buy a genuine OEM DJI Agras pump signal line? Ares Acres is an authorized DJI Agras reseller stocking genuine OEM spray system wiring for the T40 and T20P, with free and fast shipping to U.S. customers. Same-day shipping and tracking apply to in-stock parts.

How do I prove the fault is the wire and not the pump?

Make the aircraft misbehave with your hands. With clean water in the tank and the spray system running, flex and gently pull the harness one short span at a time while somebody watches pump behavior and the fault messages. A pump does not respond to being touched; a failing cable does. If the fault can be provoked at one span, mark it with tape and you have both the diagnosis and the location.

My meter says the cable is fine but the fault comes back in flight. What am I missing?

You tested it lying still. Strands that have fatigued inside an intact jacket usually read continuous at rest and go open the instant the cable is bent, which is why static checks clear cables that are failing in the air. Put the meter on one conductor end to end, then work the cable through its full range of bend while you watch the reading. Any flicker condemns it.

What resistance should the conductors read?

DJI does not publish values for this line in the general operator documentation, and a made up figure would be worse than none. Test by comparison instead. Check every conductor end to end, then check each against the others and against any shield, and look for the odd one out: a conductor that will not pass where its siblings do, or a path between conductors that should be isolated from each other.

The fault only happens while I am spraying and never on a dry flight. Why?

That pattern points at moisture tracking across contaminated contacts rather than a broken wire. Product residue inside a connector shell becomes conductive as soon as it takes on liquid, and the pump bay is only wet while the aircraft is working. Clean and inspect both halves of the connector, and look upstream for the weeping fitting or bad drip loop that has been feeding liquid into it.

Do I need to replace the connector in the aircraft too?

Inspect it before you decide. If the pins show green or white bloom, a contact has gone dark or blackened, or a pin sits lower than its neighbors, the mating half has taken damage as well and a new cable plugged into it reproduces the fault within weeks. Blackened contacts in particular mean current has been arcing across a poor joint, which never damages only one side.

Does it matter how I route the new cable as long as it reaches?

It matters more than the cable itself. Reproduce the original route exactly, including the slack, which is a service loop that lets the cable move with the airframe rather than being stretched by it. Keep the low point below the connector so water drips away instead of running into the shell, and keep the line out of every fold, hinge, and pivot path on the aircraft.

Should I put dielectric grease in the connector?

Not unless DJI specifies it for that connector. Sealed connectors rely on their own seals, and packing grease into one can hold pins from seating fully and trap contamination against the contacts, which is the failure you were trying to prevent. Clean, dry, correctly latched, and routed so water runs away from the shell does more good than any additive.

How tight should the zip ties be?

Snug enough that the cable cannot travel along its route or slap against structure, and no tighter. A tie pulled down until it indents the jacket concentrates stress at that point, and vibration works it through the insulation over a season the same way a saw works through wood. Use the original clip and tie locations rather than adding your own, and check nothing sits where an arm folds onto it.