Frequently Asked Questions
Why VARIPROP?
The SPW feathering propeller VARIPROP offers excellent sailing, ahead, and astern performance. Each propeller comes standard with external pitch adjustment screws. This allows you to independently optimize the propeller pitch for ahead and/or astern, according to your vessel's performance and engine characteristics.
For which vessels is VARIPROP suitable / in which versions is it available?
VARIPROP is available in 2, 3, 4, or 5-blade versions and is designed for engines ranging from 12 to 750 horsepower. VARIPROP is a robust propeller, featuring few components, stronger gearing, and additionally integrating mechanical soft stop shock absorption.
How do I install VARIPROP on my boat?
Installing VARIPROP is remarkably simple as it does not need to be disassembled. The pitch is set for your sailing yacht, so you only need to unpack your VARIPROP from the box and enjoy sailing after easy installation.
How do I know which sailing propeller is right for my sailing yacht?
The optimal number of blades is determined by the technical specifications of the boat and the engine, as well as the drive system design. Each propeller is individually calculated and manufactured. SPW GmbH has decades of experience specifically in the calculation and design of ship propellers. Just send us a propeller request for a free quote!
What materials are VARIPROP and VARIFOLD made of?
All propellers in the SPW Vari family are made of high-strength nickel-aluminium-bronze (AB2) for durability. They are Ice-Class materials.
Where can I view SPW propellers and get advice?
You can find us at many trade fairs in Germany and Europe. Check our website for trade fair dates or visit us at our SPW showroom in Bremerhaven. We look forward to your visit. Additionally, our products are available through our international dealers.
Are SPW propellers ready in stock?
Each propeller is made to order and individually for you. The required parts are readily available.
What is the delivery time?
Usually between 3-5 working days.
How often do I need to change the anode?
We recommend changing the anode once per season or according to its condition. Only use genuine SPW anodes to ensure the safety of your propeller.
What service does a VARIPROP feathering propeller need?
An SPW feathering propeller should be greased with SPW-EP/SAL special grease at least once per season, and the propeller anode and pitch settings should be visually checked. These service tasks only take a few minutes. After 5-6 years, we recommend sending the feathering propeller to the factory for inspection.
Are there dealers outside of Germany who distribute SPW products?
SPW GmbH has a global dealer network. For more information, visit our website under "Dealers."
Are feathering propellers also suitable for sailboats with electric propulsion?
Yes, VARIPROP is individually designed for the performance of the electric motor and is therefore very suitable for yachts with electric propulsion.
Does VARIPROP fit under long keels?
VARIPROP is significantly shorter than any folding propeller and fits even under long keels into small well openings, as well as boats with rudder skegs.
What is a DNV GL type approval?
VARIPROP, including VARIPROP XLS for superyachts, has received series approval from the certification company "DNV GL." This certificate represents the qualitative review of the product by an independent organization, guaranteeing reliable use, similar to "TÜV" certification for cars. Thus, they are the only feathering propellers worldwide with DNV approval.
Can VARIPROP be mounted underwater?
Yes, however, we recommend mounting it dry.
How do I clean my VARIPROP?
Remove fouling with a brush and lime deposits with lime remover or vinegar.
How do I protect my propeller from fouling?
To protect against fouling, you can use antifouling with primer.
What are the effects of changing the pitch of my VARIPROP?
You have the option to change the pitch for ahead and astern independently. For example, adjusting the pitch by half a turn (180°) at the adjustment screws corresponds to a pitch change of approximately 1" for VARIPROP GP 107. This means that the engine speed is reduced by approximately 200 rpm when increasing the pitch by 1" and accordingly increased when reducing the pitch. You can find the approximate change in engine speed for your VARIPROP model in the manual.
I want to have a prop walk effect in reverse when docking. How should I adjust the VARIPROP?
To achieve a stronger prop walk effect, increase the pitch in reverse.
Where can I get spare parts and accessories for my propeller?
You can get accessories from our dealers.
I want to convert my boat to electric propulsion – is that possible with my propeller?
Please contact us for a calculation of the installation.
How do I find the boat data for calculating my propeller?
Nameplates of the engine and gearbox.
How do I put the VARIPROP in the sailing position?
The VARIPROP automatically turns to the sailing position when the shaft stops. When engaging the gear, the blades automatically turn to the working position for ahead or astern.
Maintain a forward speed of 3 to 4 knots.
For a mechanical gearbox, shift to neutral, turn off the engine, and briefly engage reverse gear with the engine stopped to stop the shaft. Then shift back to neutral.
For a hydraulic gearbox, stop the engine while the gearbox remains in forward gear. The resulting residual oil pressure in the gearbox is usually sufficient to resist the shaft, causing the propeller to immediately turn to the sailing position.
What do I need to consider when shifting the VARIPROP?
When shifting from "ahead" to "astern" or vice versa, do so at a maximum engine speed of 1200 rpm to ensure gentle shifting of the propeller. This speed range should only be exceeded for necessary manoeuvres.
Why does VARIPROP need to be greased?
The VARIPROP housing is filled with grease, protecting the gears from wear. Regular greasing of the VARIPROP increases its lifespan.
Which grease does VARIPROP need?
The propeller housing must always be filled with seawater-resistant grease. We recommend our special grease with high viscosity and adhesion resistance. This helps to prevent rapid washing out.
How is VARIPROP removed from the shaft?
To remove VARIPROP from the shaft, a puller is required. Detailed instructions are included in the manual, available for download.
How is VARIPROP removed from the saildrive?
VARIPROP can be pulled off the saildrive without a puller after releasing the prop nut.