I love finding new uses for tools that I already own. A rotary tool -- often referred to as a Dremel, echoing one of the most popular brand names -- has a lot of attachments and potential applications. Here's an overview of the types of attachments available and some potential uses.
A Black & Decker rotary tool was one of my very first "power tool" purchases over a decade ago, and while I get more use out of my bigger more powerful tools these days -- including both a spiral saw and palm router, which are really more powerful versions of this type of tool -- I still find a surprising number of uses for my Dremel (I have an actual Dremel now) in the detail work.
We should start with the sheer number and type of attachments. This poster is the best representation I've found of what rotary tool accessories are available, although there are also many more accessories and job-specific attachments manufactured by others.
(That's not the whole poster, it's just the part I could fit in the available space. You can find the full version here.)
Here's what those accessories can do, and a few practical(ish) applications.
A rotary tool can cut with either a wheel or a straight bit. The cut-off wheels are fairly tiny, and while I've used them on occasion (mostly for detail metal work and trimming some sharp plastic edges) I feel like the real cutting power of a rotary tool is in the multipurpose straight bits.
You can use these for cutting holes in plater board various thicknesses of wood. I usually switch to a bigger tool if I want to cut cutting through any wood that's more than a centimetre thick.
I find the cutting kit which has a piece that keeps the bit square to a flat surface is necessary when making straight cuts.
A lot of small carving projects -- like decorative designs on tables, frames, and pretty much anything else constructed of wood -- can be accomplished with wood carving bits and a little practice. There are also metal bits for engraving, say, your name on your tools so that no one "borrows" them permanently. I also find a flex-shaft attachment is handy for this type of work, and much better for smaller hands than gripping the full-sized rotary tool.
The other way you can carve wood with this type of tool is by using a one of the straight multipurpose cutting bits. I've often used the edge of these bits as a kind of "power whittle" when shaping wood. (Here's an example.)
You wouldn't want to use a rotary tool to sand a large, flat surface, but it's extremely useful if you're sanding intricate details in furniture, moulding, or metal pieces. You can also use the triangular bits in tough to reach corners on flat surfaces -- these tools can take off a lot of material, so it's a good idea to practice on scrap wood first and use a light touch.
I've also heard that you can use these sanding wheels to trim a dog's nails, which I thought sounded a little crazy, but when I found the accessories poster mentioned above, I saw that Dremel actually has a manual for exactly this thing -- using the tool to cut your dog's nails. So, there's that. I don't have dogs -- I have donkeys -- so I don't know the first thing about canine nail trimming, but I thought this was interesting. If anyone has done this, I'd love to know how it worked (and if the dog was cool with a power tool being that close to its feet.)
This is one of the more handy uses for this tool, at least around my house, where I'm constantly in a state of tearing out or patching tile. Here's a video on how grout removal works with a rotary tool.
I would also recommend practising before doing this, because it is very easy to damage the tile if your hand slips.
I've heard of people using the grinding attachments to sharpen knives and other tools. I personally haven't used my rotary tool for that, but I have used it to grind down a few sharp spots on some metal roofing that I used on a chicken coop.
Listen, I'm not much one for cleaning, but you have to admit there's something appealing about tiny wire brushes. I've used a few of these from time to time, particularly when cleaning my tools. They don't last a super-long time, but we're also talking about very small bits, so that's to be expected to some degree.
There are also a number of household polishing uses you might use this for, like cleaning nooks and crannies on silver or jewellery. (Note of caution, I wouldn't recommend cleaning necklace chains with any kind of rotary tool, getting the chain wrapped around the shaft is a recipe for disaster and it can happen quick!)
I know that all the woodworking purists out there are going to die a little inside when I say this, but there was a time where I was much more comfortable using a rotary tool than a coping saw, and actually used this quite effectively to cope baseboard and crown moulding. I used a multipurpose cutting bit to shave wood off at the right angle, and while I've had plenty of practice (and prefer) a coping saw these days, right out of the gate I found the hand saw very frustrating, and this worked as an alternative. (Above, you'll find a decent video of using one of the cutting wheels to do something similar.)
This is by no means a comprehensive list of everything you can do with a rotary tool, but it may give you a few ideas about how you can purpose a tool like this in different ways.
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