You want to give your bicycle’s frame a new color. But the frame is made of aluminum—a soft metal that fatigues quickly—so you want to know if you can have it sandblasted or not.
Aluminum bicycle frames shouldn’t be sandblasted because silica sand can etch the metal. You can still blast them, but you will need to use a softer blasting media such as walnut shells, glass beads, or plastic beads.
Blasting metals is an abrasive process.
By using compressed air to shoot tiny particles at high speeds at the metal, you’re able to remove all foreign matter, such as paint and plastics, from its surface.
These tiny particles are called “blasting media” or “blasting agents.”
Not all blasting agents are created equal. Silica sand, for example, is hard and therefore tough on metals. Aluminum is a soft metal, so blasting it with silica sand can chip away at the surface and stress it in a way that can cause it to fatigue faster than it otherwise would.
If you want to change the color of your bike frame—and do it the right way, by stripping down all of the existing paint—the good news is that you can still get it blasted.
You just need to use softer and gentler blasting media, such as crushed walnut shells, glass beads, or plastic beads, instead of silica sand.
Can You Do It Yourself?
Especially if you’re the Do-It-Yourself kinda guy or gal, it’s tempting to go to Amazon, buy an abrasive blaster for a few hundred bucks, and try to blast your bike’s frame in your backyard or garage.
However, there’s more to abrasive blasting than loading up a tank with blast media and pointing the gun to the bike’s frame. It can take years to master the ins and outs of this process—and you’re not guaranteed to get it right the first time.
When in doubt, spare yourself the equipment, the headache, and the awkward conversation with the guys at the bike shop. Ask a car mechanic you know to point you to someone who sandblasts car parts for a living and get them to do the job.
Chances are it will be cheaper than you think, and it will cost you less than buying blasting equipment that you’ll probably never have (or want) to use again.
How Much Will It Cost to Sandblast Your Bike’s Frame?
Depending on where you live and who you work with, sandblasting costs between $50 and $75 per hour. This is the cost of labor, which usually doesn’t cover the cost of the abrasive, which you’ll have to pay extra for.
Since sandblasting is usually done by paint shops that also provide painting services, you can have your bike’s frame blasted and painted for anywhere from $100 to $250 depending on the paint and the application process.
Consider this information as a general guideline, and don’t be surprised if, after looking at Google Maps or flicking through the yellow pages, the final price ends up being slightly lower or higher than what’s indicated here.
These days, inflation is everywhere, from the paint shop’s electricity bill to the wages their pay their employees and the blast media and paint products they use, so the only way to know the cost is to get an estimate.
Is Powder Coating Aluminum Bike Frames a Good Idea?
There’s heated debate in the cycling community whether powder coating aluminum bicycle frames is a good idea or not.
Powder coating is the process of applying dry, electrostatically-charged paint to the bike frame, then baking it onto the metal to form a hard finish.
The electric charge helps the paint particles adhere to the metal. The baking process turns them into a hard, sturdy finish that doesn’t chip easily and lasts from a few years to a decade (depending on how well you look after your frame).
The baking is done in a kiln, at a temperature from 350°F (175°C) to 450°F (230°C). The melting point of the aluminum alloys used on most bikes is anywhere from 900°F (480°C) to 1,200°F (650°C).
So there’s no need to worry about “melting” your frame. But some riders are concerned that prolonged exposure to the high heat in the kiln can weaken the aluminum and cause it to fatigue faster (and fatigue leads to cracks).
Some frame manufacturers do, others advise against it. Ultimately, whether to powder-coat or wet-paint your bike’s frame a choice you’ll have to make knowing the pros and cons of each. Just remember that wet paint is nowhere near as durable as powder coating.
You shouldn’t sandblast aluminum bike frames. But, to strip off the old paint, you can blast them with softer blasting media such as walnut shells, glass beads, and plastic beads.
Once you’re done with the blasting and your frame looks as shiny as when it first came out of the factory, you need to decide whether to wet-paint or powder-coat it. Wet paint is cheaper, but peels off easily. Dry coating is pricier and may add fatigue to the frame… but the finish is amazing and lasts really long.