Technical Specifications
- Types
- Solid (heavy duty) / Hollow (standard)
- Thread OD
- 38mm ACME thread
- Adjustment Range
- 150mm – 600mm (1000mm extended)
- Base Plate
- 150x150x6mm steel with anti-slip pattern
- Material
- Q235B / S235JR structural steel
- Surface Treatment
- Hot dip galvanized to ISO 1461
Base Jacks & Top Jacks
Ringlock base jacks and top jacks are essential height-adjustable components that provide both leveling capability and load transfer in ringlock scaffolding systems. Base jacks are installed at the bottom of vertical standards to compensate for uneven ground surfaces and transfer the scaffold load safely to the foundation. Top jacks are installed at the top of standards to support formwork beams, timber bearers, steel beams, or scaffold planks in shoring applications.
As a professional scaffold jack manufacturer based in Nanjing, China, LuckyScaffolding produces both solid and hollow type jacks. Solid base jacks are machined from solid round steel bar, offering maximum load capacity and durability for heavy-duty shoring towers. Hollow base jacks are made from threaded steel tube, providing a lighter and more economical solution for standard access scaffolding where ultimate load capacity is less critical.
Our jacks feature high-strength ACME threads for smooth adjustment and self-cleaning action, even when coated with concrete or dirt. The base plate measures 150mm x 150mm x 6mm and includes an anti-slip pattern for secure footing on concrete, timber, or steel surfaces. All jacks are hot dip galvanized for corrosion protection.
We supply adjustable scaffold jacks to construction contractors, formwork companies, scaffold rental firms, and industrial maintenance providers worldwide. Our jacks are compatible with all major ringlock systems using 48.3mm diameter vertical standards.
Key Features
- Solid type: Machined from solid round bar, 80kN axial load capacity
- Hollow type: Threaded steel tube, 60kN axial load, lighter and cost-effective
- Adjustment range: 150mm to 600mm depending on model; 1000mm extended models available
- Thread size: 38mm diameter ACME thread for smooth, self-cleaning adjustment
- Base plate: 150x150x6mm steel with anti-slip pattern
- Swivel base option available for sloped or uneven ground conditions
Base Jacks & Top Jacks Specification Table
Detailed product codes, dimensions, materials, weights with metric and imperial units.
| Code | Item | Outer Diameter × Wall Thickness | Length | Weight | ||
|---|---|---|---|---|---|---|
| Metric | Imperial | KG | LBS | |||
| LS-BJS001 | Solid Base Jack 38x600mm | Solid 38mm | 600mm | 1'11" | 5.2KG | 11.5LBS |
| LS-BJS002 | Solid Base Jack 38x1000mm | Solid 38mm | 1000mm | 3'3" | 7.8KG | 17.2LBS |
| LS-BJH001 | Hollow Base Jack 38x600mm | Hollow 38mm | 600mm | 1'11" | 4.1KG | 9.0LBS |
| LS-BJH002 | Hollow Base Jack 38x1000mm | Hollow 38mm | 1000mm | 3'3" | 6.2KG | 13.7LBS |
| LS-UHS001 | Solid Top Jack 38x600mm | Solid 38mm | 600mm | 1'11" | 5.5KG | 12.1LBS |
| LS-UHH001 | Hollow Top Jack 38x600mm | Hollow 38mm | 600mm | 1'11" | 4.4KG | 9.7LBS |
* Weights are approximate and may vary slightly due to galvanizing thickness. Custom sizes and models available on request.
Frequently Asked Questions
When should I use solid base jacks versus hollow base jacks?
Use solid base jacks for heavy-duty shoring towers, formwork support, and applications where axial loads exceed 60kN per leg. Use hollow base jacks for standard access scaffolding, facade work, and light-duty platforms where weight savings and cost efficiency are more important than maximum load capacity.
What is the safe working load of your base jacks?
Our solid base jacks are rated for 80kN axial working load with a safety factor of 2.0. Hollow base jacks are rated for 60kN axial working load. Both ratings assume the jack is properly seated on a firm, level foundation. On soft ground, additional sole boards or base plates may be required.
Can I get base jacks with swivel bases for sloped ground?
Yes, swivel base jacks are available for projects with sloped or irregular ground conditions. The swivel mechanism allows the base plate to sit flat while the threaded stem remains vertical. Please specify swivel base when ordering.
What is the difference between a base jack and a top jack?
A base jack has a flat square base plate and is used at the bottom of standards to level the scaffold and transfer load to the ground. A top jack has a U-shaped top cradle and is used at the top of standards to support horizontal beams, formwork, or timber bearers in shoring applications.
How do I calculate how many base jacks I need?
You need one base jack for every vertical standard in your scaffold. For a typical access platform with standards at 2.5m x 2.0m centers, you need 4 base jacks per bay. For shoring towers, count the number of standard legs and add 10% spares.
Can base jacks be used on uneven ground?
Base jacks are designed to compensate for minor ground irregularities up to their maximum adjustment range. For significantly uneven ground, use swivel base jacks or place timber sole boards under the base plates to distribute the load. Never use base jacks to compensate for large height differences — use longer or shorter standards instead.
Do you supply base jack extensions or couplers?
Yes, we supply base jack extension tubes that can be fitted between the jack and the standard to achieve greater adjustment ranges. We also supply jack couplers for connecting two jacks in series for special applications.
Need a Quote for Base Jacks & Top Jacks?
Send us the models and quantities you need. We reply within 12 hours.