When it comes to polishing gemstones, a Dremel is an excellent tool. Use it right, and you can get excellent, professional results. But just how do you do that?
We’re going to take you through everything you need to know about how to polish gemstones with a Dremel. And by the time we’ve finished, you’ll be ready to start polishing with confidence!
So step this way and get ready to craft a beautifully polished gemstone…
Tools and equipment
- Mild dishwashing soap
- Large bowl – it needs to be big enough to submerge all the stones you want to polish
- Hot water
- Old toothbrush or scouring pad
- Clean cotton towel
- Small vice clamp
- Face mask – N95 or finer
- Protective glasses – make sure they’re ANSI rated
- Protective gloves
- 600 grit sanding paper
- 800 grit sanding paper
- 1,000-1,2000 grit sanding paper
- Dremel
- Dremel sanding attachment
- Dremel polishing wheel attachment
- Rock polishing compound
- Small piece of denim, or other tough fabric
Step-by-step guide on How to Polish Gemstones with a Dremel
Step 1: Ensure your rocks are clean
The first stage of the process is to remove any dirt and debris from the surface of your unpolished rocks.
Fill your container with enough hot water to fully submerge all the rocks you’ll be polishing. Add a few drops of liquid dishwashing soap and then place the rocks inside.
Agitate the water gently with your hands. This will encourage loose dirt to leave the surface. Now leave the rocks to soak for about five minutes.
When the time’s up, take your old toothbrush and use it to scrub all over the surface of the rocks. If you don’t have a toothbrush, a nailbrush or scouring pad will work just as well. You just want something abrasive enough to get rid of the dirt.
Rinse the rocks in the soapy water every few seconds. This will ensure the dirt goes into the water, rather than just being moved across the surface of the gemstones.
Step 2: Dry your rocks
Remove your rocks from the container and give them a final rinse under running water. Now leave them to air dry on a clean cotton towel. If you want to speed things along, you can pat them dry with the towel.
When they’re completely dry, inspect them carefully. Are there any remaining specks of dirt? If so, now is the time to get rid of them. As before, use hot soapy water and a brush or scouring pad. Then leave them to dry out before moving on to the next step.
You can also sand your rocks while they’re wet. This has some advantages, as they will produce less dust.
Step 3: Prepare for sanding
There are two elements to the preparation needed for sanding. The first relates to your work surface. The second relates to you.
To begin with, find a large, flat, work surface and attach your vice clamp.
A work bench is ideal, but don’t worry if you don’t have one. You can purchase small vice clamps that can be fixed to pretty much any flat surface. Just make sure your chosen surface is stable, and the right height for you to work comfortably.
The clamp doesn’t need to be huge either – just large enough to hold your rock securely. You can pick one up very cheaply from any hardware store.
When the clamp is in place, insert your rock, ready to begin sanding. Place the sanding attachment in your Dremel.
Now put on your work gloves, protective eyewear and mask. Rock dust can be dangerous and the Dremel is sharp – so don’t skimp on this step.
Pro tip: Position your rock so that the largest surface area is facing upwards. This is the best place to start sanding.
Step 4: Sand with low grit sandpaper
You’re now ready to get to work on your rock.
For this first stage of sanding, you’ll need low grit sandpaper – 600 grit is ideal. Slide the band of sandpaper onto your Dremel. Now begin by sanding the largest face of the rock.
When you’ve ground the whole face, reposition the rock in the vice. You want to rotate it just enough that the next unsanded portion of the rock is visible. Now repeat the process.
Keep going until you’ve covered every part of the rock. Don’t worry if the sanding isn’t perfect at this stage. We’re going to refine the finish over the next few steps.
Step 5: Repeat with medium and high grit sandpaper
Now swap for a medium grit sandpaper. You want something around the 800 grit mark. Start once more by positioning the rock so that the largest surface can be sanded. Repeat the process, rotating the rock as you finish one surface, and moving on to the next.
When you’ve finished sanding the whole surface with the medium grit paper, move onto the fine grit. This can be anywhere between 1,000 and 1,200 grit. As before, start by sanding the largest surface, moving methodically over the rock until the whole surface is smooth.
Keep going until the whole surface of the rock begins to take on a shiny finish. Using the very tip of the sanding bit will help you achieve an ultra-smooth result.
Pro tip: Pay particular attention to any tight crevices or sharp angles. It’s well worth spending extra time sanding these areas with the medium grit paper before moving onto the finer grit.
Step 6: Use the polishing wheel
With sanding complete, it’s time to move onto polishing. For this, you’ll need to exchange the sandpaper attachment for the polishing one.
The polishing wheel is a small fluffy piece of felt. You’ll use this to buff the surface of the gemstone to a brighter shine.
When you’ve attached your polishing wheel to the Dremel, switch it on. Now dip it gently into a pot of rock polishing compound. Leave it there for a few seconds until the wheel is completely coated in the powder.
Now apply the compound to each part of the rock. When you’ve finished one surface, rotate the rock in the vice and repeat the process. It’s time to move to the next section once the area you’re working on is nice and shiny. This will usually take a few minutes.
Keep going until you’ve achieved the level of shine you want.
Pro tip: You can get an even brighter finish by giving your rock a final polish by hand. Use a piece of tough fabric – denim works well – and rub it across the surface of the stone. It will bring out the reflective qualities of your gemstone beautifully.
Extra tips
- Choose the right Dremel for rock polishing. You want something that has low RPM, so variable speed options are best. Models with a single speed or high-low options won’t work as well.
- There are pros and cons to battery-powered Dremels, as opposed to plug-in versions. The former are convenient to use, without having to worry about a trailing wire. But you may find that you need more than a single charge to finish polishing your rocks.
- Make sure you work in a well-ventilated area. If you can work outside, so much the better.
- Make sure your face mask will be able to trap the tiny particles of rock dust that will be generated. A standard dust mask won’t do it. You’ll need at least an N95 rated mask, or ideally a respirator that covers half your face, together with the right filters.
- When sanding tight angles, keep the bit as flat as possible to the rock surface. That will help you sand down these areas nice and evenly.
- It’s important to select the right polishing wheel for the best results. You’ll want one that’s small enough to fit into any nooks and crannies on the surface of the gemstone. Most hardware stores will have a good selection, or you can buy them online.
- Don’t press down too hard when you’re sanding or polishing. If you do, you’ll find the diamond bits wear down very quickly.
- You can add an extra stage of sanding by hand to get even finer results. For this, you’ll want to begin with sandpaper that’s 1,500 or 2,000 grit. Specialist retailers will offer sandpaper up to 5,000 grit. A maximum of 2,500 grit, however, should be enough for all but the pickiest perfectionists.
- When it comes to rock polishing compound, cerium oxide works well for most gemstones. You’ll need to mix the powder with water to form a paste, though, before you apply it.
- Move the polishing wheel in small circles as you work – it’s more effective than moving forward and back. And set your Dremel to low speed to avoid flinging the powder or paste all over the place.
Ready for perfectly polished gemstones?
We hope you’ve enjoyed our step-by-step guide to how to polish gemstones with a Dremel! Take your time and follow the instructions carefully, and you’ll get great results.
Just remember to protect yourself with the right PPE, and work in a well-ventilated area. Rock dust can be very hazardous to your health. But with a few simple steps, you can create a safe working environment.
We hope you enjoy your next gemstone polishing project!
