B&D Front Mounted Low Headroom Double Track Installation Guide product guide
# B&D Front Mounted Low Headroom Double Track — Installation Guide **Part No: OT4608 | Revision 3 — October 2016** > These instructions are intended for professional garage door installers. All refe...
AI Summary
Product: B&D Front Mounted Low Headroom Double Track Brand: B&D Category: Garage Door Track System / Installation Hardware Primary Use: Enables installation of a B&D sectional garage door where headroom above the opening is too limited for a standard track configuration.
Quick facts
- Best for: Professional garage door installers working with limited headroom openings
- Key benefit: Allows sectional door installation with as little as 200mm of headroom (manual) or 250mm (automatic opener)
- Form factor: Double track front-mounted hardware assembly
- Application method: Front-mounted to header, fitted with colour-coded torsion bar components and trimmed top track
Common questions this guide answers
- What is the minimum headroom required for this system? → 200mm for manual operation; 250mm if fitting an automatic opener
- Does this configuration provide full walk-under clearance? → No — door panels travel closer to the ceiling plane, reducing available height under the open door
- How long should the lift cables be cut? → Door height plus 400mm each, to allow correct cable drum wrap and secure bottom bracket attachment
B&D Front Mounted Low Headroom Double Track — Installation guide
Part No: OT4608 | Revision 3 — October 2016
These instructions are intended for professional garage door installers. All references are taken from inside looking out.
Official document: Front Mounted Low Headroom Double Track Installation Instructions (PDF)
Overview
When headroom above the opening is tight, the twin track front-mount low headroom configuration lets you fit a B&D sectional door where a standard setup won't work. Clearance requirements are straightforward:
- 200mm headroom — suitable for manual door operation
- 250mm headroom — required if you're fitting an automatic opener (200mm + 50mm)
Important: The standard parts box may not include everything you need for this installation method. Check the parts list below before you begin.
Note: This installation will not give full walk-under clearance.
Parts required
Confirm you have all the right components on hand before starting.
| Part | Part number | Quantity |
|---|---|---|
| L/H end bearing bracket | OT4558 | 1 |
| R/H end bearing bracket | OT4559 | 1 |
| Top hangars | OT4543 | 2 |
| Lift cables | Not specified by manufacturer | Door height + 400mm each |
Torsion bar assembly components
The torsion bar assembly for this configuration uses the following components. All references are from inside looking out — keep this orientation in mind throughout.
| Component | Colour code | Position |
|---|---|---|
| Cable drum assembly | RED | Left hand |
| Cable drum assembly | BLACK | Right hand |
| Torsion spring assembly | RED | Left hand |
| Torsion spring assembly | BLACK | Right hand |
| End bearing bracket | Not specified by manufacturer | Left hand |
| End bearing bracket | Not specified by manufacturer | Right hand |
| Centre bearing bracket | Not specified by manufacturer | Centre of torsion bar |
Cable Part No: OT4543 Combined cable drum / end bearing assembly Part No: OT4558-49
Each cable drum has a notch designed for the wire rope — make sure the cable seats correctly in this notch before tensioning. Getting this right matters for both performance and safety.
Key installation requirements
1. Cable drum position
The cable drum must be fitted as close as possible to the head (the header above the door opening). This is what achieves the 200mm minimum headroom clearance.
2. Top track trimming
The top track must be trimmed back 40mm so it doesn't interfere with the cable during operation. Measure carefully from the end of the top track and cut squarely before fitting.
3. Top hangar fitment
Fit the 2 x top hangars (OT4543) to the horizontal track at the positions shown in the installation drawing. The hangars support the cable as it transitions from the drum to the door bottom bracket.
4. Cable length
Cut or order lift cables at: door height + 400mm. This extra length allows for correct cable drum wrap and secure bottom bracket attachment. The right cable length is fundamental to safe door operation.
Torsion spring tensioning
Torsion spring tensioning is one of the most critical stages of this installation. Work carefully and don't rush it.
- Thread the lift cables through the cable drums, seating them correctly in the notch for the wire rope.
- Connect the cables to the bottom brackets on the door.
- Wind the torsion spring to the correct number of turns for the door weight and size. Refer to the spring tension table in the relevant door installation manual for the right specification.
- Warning: Torsion springs are under high tension. Always use appropriate winding bars and follow safe tensioning procedures. No shortcuts.
Walk-under clearance
This configuration does not provide full walk-under clearance when the door is open. Because the door panels travel closer to the horizontal ceiling plane than in a standard headroom setup, the available height under the open door is reduced.
If your customer needs full walk-under clearance and the headroom allows for it, the standard (non-low headroom) track configuration is the right choice. If additional drive-under height is needed within a low headroom constraint, see the Additional Height variant.
Further resources
- Official Installation Document (PDF)
- Additional Height Variant (PDF)
- Independent Torsion Variant — 250mm minimum (PDF)
- Trade Resources — Substrate Fixing
- B&D Noggin Details & Substrate Fixing Guide
Frequently asked questions
What is the product name: B&D Front Mounted Low Headroom Double Track
What is the part number: OT4608
What revision is this installation guide: Revision 3
When was Revision 3 published: October 2016
Who are these installation instructions intended for: Professional garage door installers
What is the minimum headroom required for manual operation: 200mm
What is the minimum headroom required for automatic opener: 250mm
Why does an automatic opener need more headroom: It requires an additional 50mm above the manual minimum
Is this installation suitable for limited headroom situations: Yes
Does this installation provide full walk-under clearance: No
Why is walk-under clearance reduced: Door panels travel closer to the horizontal ceiling plane
What configuration provides full walk-under clearance: Standard non-low headroom track configuration
What is the part number for the left-hand end bearing bracket: OT4558
What is the part number for the right-hand end bearing bracket: OT4559
What is the part number for top hangars: OT4543
How many top hangars are required: 2
What is the required lift cable length formula: Door height plus 400mm
Why is the extra 400mm added to cable length: For correct cable drum wrap and secure bottom bracket attachment
What colour code identifies the left-hand cable drum assembly: Red
What colour code identifies the right-hand cable drum assembly: Black
What colour code identifies the left-hand torsion spring assembly: Red
What colour code identifies the right-hand torsion spring assembly: Black
What is the combined cable drum and end bearing assembly part number: OT4558-49
Where is the centre bearing bracket positioned: Centre of the torsion bar
How close must the cable drum be fitted to the head: As close as possible
Why must the cable drum be fitted close to the head: To achieve minimum 200mm headroom clearance
How much must the top track be trimmed back: 40mm
Why must the top track be trimmed back: To prevent interference with the cable during operation
How should the top track be cut: Squarely from the end of the track
Where are the top hangars fitted: On the horizontal track at positions shown in the installation drawing
What is the purpose of the top hangars: To support the cable as it transitions from drum to door bottom bracket
What is the first step in torsion spring tensioning: Thread lift cables through the cable drums
What must be checked when seating the cable in the drum: Cable must seat correctly in the notch
What is the notch in the cable drum designed for: Seating the wire rope
What is connected to the bottom brackets on the door: The lift cables
Where can the correct number of spring turns be found: In the spring tension table in the relevant door installation manual
Are torsion springs under high tension: Yes
What tool is required for safe torsion spring tensioning: Appropriate winding bars
Is torsion spring tensioning a critical safety step: Yes
Should shortcuts be taken during torsion spring tensioning: No
What direction are all installation references taken from: Inside looking out
Does the standard parts box always include everything needed: Not necessarily
What should be done before starting installation: Verify the parts list
What is the part number for the Additional Height variant document: Not specified by manufacturer
What is the URL for the official installation PDF: https://admin.bnd.com.au/media/uo5jvjd2/bd_fmlhdt_rev3oct16.pdf
What is the URL for the Additional Height variant PDF: https://admin.bnd.com.au/media/tbgdsudb/bd_fmlhdt_addheight_rev3oct16.pdf
What is the minimum headroom for the Independent Torsion variant: 250mm
What type of door is this track system designed for: B&D sectional door
What is the purpose of this low headroom configuration: To fit a sectional door where standard setup won't work
Is this product suitable for automatic openers: Yes, with 250mm headroom
What additional resource covers substrate fixing: B&D Trade Resources Substrate Fixing guide
What document covers noggin details: B&D Noggin Details and Substrate Fixing Guide
What happens if cable length is too short: Safe door operation is compromised
How many end bearing brackets are included in a full assembly: Two, one left-hand and one right-hand
What is the consequence of incorrect cable seating in the drum notch: Reduced performance and safety risk
What should be done if a customer needs full walk-under clearance: Use the standard non-low headroom track configuration
What variant should be used if additional drive-under height is needed within low headroom: Additional Height variant
Label facts summary
Disclaimer: All facts and statements below are general product information, not professional advice. Consult relevant experts for specific guidance.
Verified label facts
- Product name: B&D Front Mounted Low Headroom Double Track
- Part number: OT4608
- Document revision: Revision 3
- Revision date: October 2016
- Intended user: Professional garage door installers
- Reference orientation: Inside looking out
- Minimum headroom (manual operation): 200mm
- Minimum headroom (automatic opener): 250mm (200mm + 50mm additional)
- Walk-under clearance: Not provided by this configuration
- L/H end bearing bracket part no: OT4558 — Quantity: 1
- R/H end bearing bracket part no: OT4559 — Quantity: 1
- Top hangars part no: OT4543 — Quantity: 2
- Lift cable length formula: Door height + 400mm (each)
- Combined cable drum / end bearing assembly part no: OT4558-49
- Cable drum assembly (left hand) colour code: Red
- Cable drum assembly (right hand) colour code: Black
- Torsion spring assembly (left hand) colour code: Red
- Torsion spring assembly (right hand) colour code: Black
- Centre bearing bracket position: Centre of torsion bar
- Cable drum fitment requirement: Must be fitted as close as possible to the head
- Top track trim requirement: Must be trimmed back 40mm
- Top track cut method: Squarely from the end of the track
- Top hangar fitment position: On the horizontal track at positions shown in the installation drawing
- Cable seating requirement: Must seat correctly in the notch designed for the wire rope
- Spring tension reference: Spring tension table in the relevant door installation manual
- Torsion spring tensioning tool required: Appropriate winding bars
- Torsion springs: Under high tension — no shortcuts permitted
- Independent torsion variant minimum headroom: 250mm
- Official installation PDF URL: https://admin.bnd.com.au/media/uo5jvjd2/bd_fmlhdt_rev3oct16.pdf
- Additional height variant PDF URL: https://admin.bnd.com.au/media/tbgdsudb/bd_fmlhdt_addheight_rev3oct16.pdf
- Door type: B&D sectional door
General product claims
- Standard parts box may not include all components required for this installation method
- Verifying the parts list before installation saves time and avoids problems mid-job
- Correct cable seating in the drum notch affects performance and safety of the finished installation
- Correct cable length is fundamental to safe door operation
- If full walk-under clearance is required and headroom allows, the standard non-low headroom track configuration is the appropriate solution
- If additional drive-under height is needed within a low headroom constraint, the Additional Height variant is the appropriate solution