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Aluminum Boat Transom Reinforcement – A Simple Tutorial

Written by Anthony Roberts / Fact checked by Jonathan Larson

aluminum boat transom reinforcement

Having an aluminum vessel is great if boaters wish to cruise for a long time without too much maintenance. Still, the boat’s antioxidants may loosen over time, especially those located in the transoms. Hence, it is important to search for an effective aluminum boat transom reinforcement.

This leads us to the question, “How to reinforce a transom on an aluminum boat?” There are many methods to strengthen transom on aluminum boat sterns or bows, but the best way to reinforce transom on vessels is to use simple materials like plyboard, PVC, etc to support plate transoms and the aluminum boat hull.

In this post, we will provide all the necessary information regarding equipment and materials used in the transom reinforcement process, like transom strengthening plate or jon boat transom plate. The article will also include an efficient tutorial on reinforcing a boat transom and present other tips.

Continue reading to learn more about our suggestions on boat transom maintenance!

What Should Be Prepared in an Aluminum Boat Transom Repair Kit?


In this part, we will provide a list of what you should include in your aluminum boat reinforcement kit box:

  • Equipment:
  • Rivets
  • Welding set
  • Lock nuts
  • Paints
  • Washers
  • Adhesives
  • Sealants: marine-grade 3M M5200, etc.
  • Tools: You should also prepare these basic tools:
  • Discs
  • Hand drills
  • Grinding
  • Hammer
  • Open-socket wrench

A Method to Reinforce Your Aluminum Boat Transom—the Easiest Tutorial


Now that you have all the essential equipment and materials for reinforcing your aluminum boat transom, it’s time for you to start the process. Although there are many other ways to strengthen the transom plate, the following steps are the basis and the easiest to proceed with. Read our instructions carefully and practice with your boat!

Step 1: Prepare the proper materials

Before you start to reinforce your boat transom, the first step is to prepare all the essential tools, equipment, and materials required for the strengthening process. You may encounter certain difficulties if your aluminum boat transom repair kit is not well-equipped.

Hence, the list below presents the types of materials that are needed for the reinforcement procedure. Follow the list and purchase wisely!

  • Materials: You can choose either one or many materials from the list to use as another layer of transom plate to reinforce your aluminum boat hull.
  • Hardwood
  • Plywood
  • Fiberglass
  • PVC
  • Polycarbonate
  • Plastic
  • Aluminum plate

The preparation may sound simple, yet it requires great care and consideration. We suggest boaters select materials and tools that suit their vessels. For instance, if you expect to add more strength to your aluminum transom, it will be better to use the same type of extra transom plate.

Step 2: Clear Up the Transom and Hull Area

Now, you need to examine the section to be repaired or replaced and take measurements of the transom area. You can place your new material in the particular section to confirm that it fits the size.

Then, start to remove and polish rotten or broken transom sections, or discard the whole weakened component for complete strengthening. Then, drill guiding holes in the specified transom positions for simple bolt and rivet placement or sealing.

These holes that consist of indicator marks will also assist you in determining whether your boat’s size specifications are sufficient for the engine and stern installations.

Step 3: Polish the new reinforcement transom component

Before sanding, bonding, or sealing, remove the transom plate and clean it well. For maximum effectiveness, use appropriate sandpaper for cleaning or strengthening transom surfaces, as well as the rear of the reinforcement material.

When all parts of the transom’s surfaces have been cleaned, add the sealant liquid or the adhesive tape.

All mounting textures are suitable for 3M M5200 sticky tape or other similar marine epoxy sealants. Before strengthening or reconstructing the boat transom, spread the sealant uniformly over the area, including the rear of your strengthening material.

Step 4: Assemble the new reinforcement transom

Now, you can assemble the transom strengthening component to its allocated location by following the guiding holes marked in the first step. Compress the reinforcement part then begin bolting it with rivets or stainless lock nuts.

Fasten all of the bolts and leave the reinforcement secured for a week so it can completely solidify. Examine it frequently to detect any hair-like gaps while utilizing polycarbonate, fiberglass or PVC, as well as plyboards for additional sealant coatings. Finally, tidy up all of the leftover areas.

Step 5: Insert the additional layer of transom reinforcement

Assess the extra parts, especially while welding and riveting transom reinforcements. If you did it correctly, transom modifications, such as rope hooks, stepboards, outboard plugs, or other fasteners can improve the stern of your boat.

Put wedges into their position to reduce porpoising and mild bowing for a simpler stride. Another useful addition is connections for a transom diverter. It will protect your vessel’s transom, motor, and hull against damage. An aluminum bottom plate helps you to install your engine while also protecting your transom or stern beam from cracking.

And that is the last step in the process of reinforcing your aluminum boat transom. After this, you can decorate the new reinforcement layer using paint and a brush. Also, to increase the capability of the transom strengthening component, use anti rust and high-temperature resistant paints.

For more details, please check out this video: 

Aluminum Boat Transom Maintenance Tips

Aside from reinforcing the transom, protecting and maintaining its quality and outlook are important tasks that boaters should pay attention to. A frequent maintenance schedule can help you detect leaks and rusty spots in time and save you a bunch of money!

Hence, here are some of our suggestions to keep your transom in a good shape:

1. Understanding the purpose of your boat

Understand your plans for your aluminum watercraft in advance so you can examine, repair, or reinforce a dependable transom arrangement. Boat transoms play an important function in reinforcing the structure of a vessel’s stern, which you should be aware of.

Decide what sort of outboard engine you will use for your power-driven watercraft in order to create the appropriate transom height. When building a fast vessel, the transom length will affect the productivity of your engine propeller. Hauling and camouflaging your craft will become easier when you install a transom on the trailer and then go hunting.

Evaluate the function of the boat, as well as the appropriate materials, gears, and gadgets for your transom restoration kit. Knowing your boat’s purposes contributes to safety and extended boat travel time. Hence, it’s essential to provide your vessel’s stern with a sturdy beam that can withstand external forces, intense weather, and turbulent waves.

2. Maintaining your boat’s transom

  • Regularly wash and polish your watercraft after each ride to remove any seawater or marine residue.
  • Repair or remove any damage that might lead to corrosion or oxidation on the aluminum boat.
  • On an aluminum watercraft, avoid combining aluminum with other metallic materials or corrosive liquids.
  • Do not use an automatic battery charger on your vessel.

3. Protecting your transom from harmful external factors

If your aluminum jon boat is used to travel in the ocean or across rough waters, it may encounter many hazardous external elements. Take into account these tips to protect your jon boat transom plate:

  • Get a portable boat lift to dry-dock your boat. The longer your aluminum vessel remains out of the water while it is not used, the better it is for your boat transom.
  • Use paints and varnishes made for metal surfaces. To avoid fractures or cracks that may weaken the transom, the base and anode plates should not be painted or coated.
  • Learn and follow other boat maintenance suggestions from expert boaters.


Installing an aluminum boat transom reinforcement is not difficult once you follow our tutorial mentioned in previous parts. Boaters will successfully reinforce their boat transom if they are aware of its function and have a well-prepared repair kit. Also, it’s important to maintain the transom and keep it away from harmful substances.

I hope that this post was helpful to your boating experience! Did you enjoy the article? Do you want to add anything else? Please let me know and leave a comment below.

Read more: Tips to mount a transducer on an aluminum boat.

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