Taking your dinged surfboard to a surf repair shop can become an expensive task, so why not learn to fix your surfboard yourself?
Of course, you could go with the classic sandpaper in hand technique, but this will take you hours when fixing multiple dings or reshaping a board.
Instead, a high-quality sander will get the job done in a fraction of the time with little to no effort.
Because buying a sander is likely not something you are familiar with, we have compiled a list of the best sanders for surfboard repairs, as well as what you will need to fix your board and a few bonus tips.
The Best Sanders for Surfboard Repair
Using a high-quality sander will speed along your surfboard sanding process like nothing else. However, with so many tools on the market, it can be tough to decide what you should use.
The below sander/ buffers are ideal for sanding your new surfboard or for repairing large dings.
This variable speed sander/ buffer is the perfect tool to get surfboard sanding underway.
The DEWALT sander has a soft start due to its variable speeds and 12 – amp motor. This is ideal for avoiding over-sanding sections of your surfboard.
The DWP849X weighs only 6.7 pounds making changing angles and rounding off the rails smooth and effortless.
The Makita 9237C is a sander/ buffer that makes a name for itself in the market. This variable speed, 100V, and 1200 W buffer offer a soft start and constant speed control under heavy loads.
Because the Makita 9237C is so easy to control, it makes the perfect surfboard sanding tool.
Although this sander is on the heavy side, it makes up for its stability and durability.
If you are looking for a cordless sander and buffer for fixing and creating surfboards, then the Milwaukee 2738 could be your answer.
Although it only packs 18 volts, this sander still runs up to 2,200 RPM, which is more than enough for your surfboard sanding needs.
This sander is lightweight and comes with the convenience of not needing to move a cable around your workshop.
What You Need to Sand a Surfboard
The first thing you will need is a variable speed sander with all its components.
Your sander should have speeds from 0 – 3,000 RPM, although slower speed will work just as well. However, they may take slightly longer.
Take note of the size of the thread accepted by your sander before purchasing a sanding pad.
You will also be needing some soft sanding blocks for the sensitive areas around the rails, tail, and nose of your board.
These areas can be done with the machine, but it is best to use your hand and sheets of 120 – 400 grit sandpaper when you are less experienced.
If you are planning to use cloth-backed sandpaper sheets on your machine (no self-adhesive pads), you will need to cut the sheets to the appropriate size and secure them with an adhesive spray such as 3M Super 77.
Lastly, you will need a stand to secure your surfboard while you are sanding it.
Shaping racks work well for this as they prevent the board from sliding. However, some well-placed trestle tables with towels between the board and the stands will work too.
Surfboard Sanding Equipment Summary
1. A hot-coated surfboard.
2. A variable speed sander/ buffer.
3. An array of different sandpaper disks (120 – 400 grit)
4. An array of sandpaper sheets (120 – 400 grit)
5. Adhesive spray (if the sandpaper disks are not self-adhesive).
6. A soft and hard sanding disk backing pad.
7. A soft and hard sanding block.
8. A wool or cotton buffer pad for final touches.
9. A trestle table or stand.
10. A mask and gloves.
How to Sand a Surfboard
The purpose of sanding your surfboard after your glass job is to smooth out and flatter the board.
This will remove the shiny glass finish, but as sanding progresses, the grit of the sandpaper is increased, which slowly brings back this shine.
This entire process can be done by hand, but good tools with a solid technique will provide faster and more consistent results.
Sanding Technique Tips and Advice
The technique is everything when it comes to power sanding. It is important to keep the sanding disk as flat as possible while sanding and maintain constant movement.
Leaving the sander in the same place will cause it to begin digging into the board, leaving small creators. These ditches are also known as burn-through.
A burn-through is more common while using smaller grit sandpaper as they tend to take off more material in less time.
To help keep this to a minimum, beginners can lower the speed of the sanders. The slower the RPM, the less material the sander will remove.
For the same risk of creating a burn-through or line in your board, it is important to keep the sander as level as possible. If you sand your board with the sander at an angle, then you will begin to create crevices on the board.
This is also why sanding the nose, tail, and rail can be difficult with a machine. If you are not confident, then there is no shame in doing these sections by hand.
It might take you slightly longer, but you will save the integrity of your board in the process.
- Keep the sander flat and level.
- Go slower with smaller grit sandpaper.
- Lower the RPM.
- Do the rails, tail, and nose by hand.
- Keep the sander constantly moving.
Sanding Down the Fin Boxes and Leash Plugs
Your first step of sanding should be to flatten the fin boxes and leash plug.
Using your medium/ hard sanding pad with a medium grit (60 – 80), make the fin boxes almost flush with the bottom of your surfboard.
Remember to continuously move the sander as not to over-sand a single area. You should also be aware that putting constant pressure in a single spot could overheat and distort the fin box.
Once the area is sanded just higher than the bottom of the board, you can turn your board over and do the same to the leash plug.
It is best to leave this slightly higher than flush as we will remove the last few millimeters with the finer grit paper at a later stage.
It is also important to try and remove material evenly around the area while removing the sander every 15 – 20 seconds to clean off the surface and make sure you are sanding straight and not removing too much.
Sanding the Deck and Underside of Your Board
Unlike sanding the fin boxes and leash plug, to sand the flats of your board, it is best to use your soft sanding pad with a higher grit (120 should do well).
It is here that you will discover how well your glass job is. The better your glass finish, the easier it will be to sand down the flat sides of your surfboard.
If your glassing job is poor, your board may be lumpy, making sanding time-consuming and difficult.
The smoother your glass finish, the easier it will be to sand your board.
Holding the sander flat against your board, begin at the bottom of your surfboard along the stringer.
Keep the sander on medium (around 1500 RPM) and apply medium pressure. As time goes, you will find the sweet spot of how much pressure you should be applying.
Remember to keep moving the sander with even pressure as you move over the surface of your board in order to prevent ditches.
During this phase, you can also smooth out the raised areas around the plugs and boxes.
Do this for both the underside and the deck of your surfboard.
Remember, your goal here is to remove all of the shiny areas while flattening the surface.
Sanding the Rails, Nose, and Tail
When sanding the curved areas of your surfboard, the goal is the same as when sanding the flats – to flatten the surface and remove the shine.
To do this, it’s best to start with a medium grit (120 – 150) and your soft sanding pad.
If you are a novice or are not as confident about this as you would like, this is a good time to put the sander down, pick up your sanding block, and get to work with your hands.
The first grit you use (120) will be the hardest as it removes the most material and therefore requires some extra muscle.
As the grit is raised, the task will begin to seem easier.
This is also a good time to remove any lines you have running down the rails that were formed from the tape you used during your hot coat.
To remove this, simply grab a razor or a scraper and begin taking off the thin line, starting at the nose and moving towards the tail of the board.
A nice tip for the edges of your board is to use a flexible sanding block or make do without one altogether.
Doing this allows the sandpaper to wrap around the rail, spreading out the pressure and maintaining a more consistent sanding.
You may also consider sanding down any shiny spots left on the deck and underside of your board that are in small crevices while you have your soft sander at hand.
Dealing With Over Sanded Sections
Remember how important it was to keep the sander moving and not apply too much pressure in order to avoid burn-throughs?
Well, the chances are that no matter how careful you have been, there will still be areas that you have burned through the fiberglass.
Do not worry about this, as it is normal for this to occur, even for the best sanders out there.
Fixing an over sanded area is important. If you do not patch up the exposed fiberglass before your board enters the ocean, water will be absorbed by these fibers and eventually make its way into the base of your board.
Allowing this to happen will result in your new surfboard becoming waterlogged and ultimately destroyed.
To fix areas that you have burned through, you have two options: Touch up the sections, or redo the hot coat.
If your board is covered in over sanded areas, you will probably want to redo the entire hot coat.
Although this may seem tedious as you will need to re-sand the board again, it will be faster than trying to mend each burn through individually.
On the other hand, if you are lucky enough to have only a few patches, then you can do some spot mending.
To do this, simply paint on a thin layer of epoxy to seal up the areas and then sand them flush with the rest of the board.
Start the sanding again with 120 grit paper, being careful not to over-sand the areas again.
Final Sanding (Fine Grit)
Once all the burn-throughs have been re-sealed it, I time to continue sanding with progressively higher grits.
The purpose of moving slowly through different grits is to bring back the shine to your board that you previously sanded away.
You can begin by using 150 grit sandpaper with your sander, then move to 220, 330, and 400.
You may also want to wet sand the board with the higher grits (320 and 400), which will give the board a smoother and more consistent finish.
Once again, if you are a novice, it is a good idea to do the rails, tail, and nose by hand to avoid over sanding; however, when using the higher grit papers, it is a lot harder to over sand because the paper will remove less material than the 120 grit.
During this process, there will be a lot of dust. You should pause once in a while to wipe off the board in order to make sure that you are consistent.
If you are happy with the result, you can consider your board finished. However, it may be a nice additive to put a wool buffer onto your sander to give the board one final polish.
This will leave your new surfboard shining like the ones you find in surf shops all over the world.
Commonly Asked Questions (FAQs)
Do you still have some questions about sanding your surfboard? It’s okay if you do because you are not the only one.
The questions answered below are common among new surfboard shapers and sanders and may include all the answers you have been looking for.
What Type of Sander Do Surfboard Shapers Use?
Each surfboard sander will have its go-to tools and brands. It is less the brand that is important to sanding a surfboard and more the capabilities of the product.
As a surfboard shaper, you will want to use a variable speed sander that has speeds from approximately 0 – 3,000 RPM.
A variable sander allows maximum control which is important to avoid over-sanding areas of your surfboard.
Your sander should also include a slow start which will prevent the sander from jumping forward when you pull the trigger.
Corded or battery run is entirely up to personal preference, and both have their advantages and disadvantages.
Any of the sanders mentioned at the start of this article are perfect examples of what a good surfboard shaping sander would look like.
How to Make Your Surfboard Shine Again?
It seems sort of contradictory to remove all the shine from your board only to make it shiny again; however, this is necessary to get the board smooth after your hot coat.
To get your board back to its shiny self, all you need to do is constantly raise the grit level of your sandpaper.
The higher the grit, the smaller the cuts it makes, which smooths out the rough sanding that has been done.
To get the best finish, it is good to wet sand during the final two stages of grit and use a woolen buffer for the final polish.
What Grit Sandpaper Should You Use for Surfboard Repair?
Whether you are fixing a ding in your surfboard or you are making a board from scratch, it is a good idea to use different grit sandpaper.
In the initial stages, when the hot coat or areas around a ding are rough, a 120 grit paper should do the job, but once you have taken off the top layer, you should progress to higher grits (150 – 400) to get that smooth, shiny touch that you are looking for.
The sanding of a surfboard is an extremely underrated talent that no article or Youtube video can truly teach.
It takes strong technique and practice to master sanding a surfboard, but it can be done when you apply some patience.
Although it is time-consuming and, at times, frustrating, learning how to use a power sander will speed up the process and leave your board with a consistent and professional finish.