Question about Dremels

[Dukhat]

I need to buy a Dremel tool for some model kit work, and I have no idea which one to get, as there are several different models out there. I would basically need it to finely cut styrene but not mangle it, obviously. Also, if there are any "must-have" accessories for it, please let me know.

 

[Ar-Pharazon]

The bits are as/more important than the tool, depending on your needs.

If you want to invest more into it, I'd suggest the one where the motor is separate from the tool & connected by a cable.

It's lighter & easier to use than the motor-in-tool ones. It's more of a professional grade.

Beyond that, there is a huge selection of bits, both Dremel brand and other brands. Sounds like you'd be after the cutting type bits rather than the grinding ones.

Whatever you get, practice on some scrap plastic, to get an idea of what speed you need to use. Too fast and it'll go crazy.

 

[Ziz]

Speed and plastic is a bit of a double-edge sword (bit?) Depending on the thickness of the plastic, high speed can melt it. At the same time though, low speed may cause the bit or cutting wheel to clog up and jam halfway through the process.

One thing I would suggest is getting two Dremels - one AC powered one (the flex shaft is available separately also) for "big" work and one of the battery powered handheld ones for finer work. The battery ones run generally slower even at their highest speed than the AC units.

 

[Albertese]

Ideally, you want something with multiple speeds to choose from. When I use a rotary tool on plastic, my strategy is to go a head and let it eat up the material. Yeah, it's messy, but, with a little bit of practice, it's not so hard to figure out how to flare out the material just the way you want where the raggedy edge can easily be broken off with your thumb and finished up nicely with some sharp blade or judicious use of sand paper or the right shaped little file.

Normally I'll use those little brown cut-off discs. I don't know what their made of, but it looks like basically compressed grit, almost like a thin, fragile ceramic. If you need to cut a wider trench with it, you can stack a few together. These little bastards break if you look at them wrong, but that's okay as they usually come in packs of 30 to 100. They're meant to be pretty disposable. This really is my "go to" tool when working plastic. Don't bother with carbide burrs or diamond bits or ceramic stones or any of that stuff. They're great for other materials, like soft metals or ceramics but they area mess with plastic.

(I'm actually a dental technician by trade and I spend all day every day using a rotary tool on gold and porcelain, plus I've been rearranging Star Trek model kit parts since I was about 12 years old, so I have a little experience with this stuff. )

--Alex

 

[Ziz]

Normally I'll use those little brown cut-off discs. I don't know what their made of, but it looks like basically compressed grit, almost like a thin, fragile ceramic. If you need to cut a wider trench with it, you can stack a few together. These little bastards break if you look at them wrong, but that's okay as they usually come in packs of 30 to 100. They're meant to be pretty disposable. This really is my "go to" tool when working plastic. Don't bother with carbide burrs or diamond bits or ceramic stones or any of that stuff. They're great for other materials, like soft metals or ceramics but they area mess with plastic.

Oh, right - the cutoff discs. Yeah, the thin ones can break easy so get some eye protection. They also make heavy duty cutoff wheels so depending on the cut, you might want to go with one of those.

 

[Patrickivan]

It boils down to this.

Buy one that plugs into the wall.
Buy one with variable speeds (with low RPMs).
Buy a flex shaft attachment that allows you to place your heavy dremel down. I don't care how small they are, they're all too heavy and the flex shaft attachment gives you SOOOO much more control because it's so light.
And don't skimp out on bits, sanding discs and cylinders. You'll go through the sanding bits fast.
As for the make, like any tool, money talks. Buy name brand and don't be cheap.

 

[Ar-Pharazon]

There are some off-brand circular saw type blades that are about 1", same as the cut off wheels, maybe a little bigger.

They might require a different mandrel than Dremel makes.

 

[Albertese]

There are some off-brand circular saw type blades that are about 1", same as the cut off wheels, maybe a little bigger.

They might require a different mandrel than Dremel makes.

Here's why it's a good idea to stick to one brand as much as possible. If you get an off-brand mandrel with a weird sized shank it might not fit the collet right. If it's a bit too tight you could potentially damage your collet, but if it's too loose you could potentially throw your bit. If it's going fast enough, you might get into more trouble than you bargained for. Of course, you could also check to see if the manufacturer of the off-brand bit also makes a collet that fits your handpiece.

Now, this stuff is usually pretty standardized across brands, so there probably won't be too many difficulties, but I've had some weird stuff happen with off-brand stuff, so just be watchful when you experiment with something new.

--Alex

 

[Dukhat]

Thanks for all your helpful replies!

Basically, I'm building some models (Kitbash replicas of the DS9 Frankenstein fleet), and there's some cutting that is a little more involved than just using a knife or hand saw. Specifically, I'm currently building the U.S.S. Yeager, and it turns out that it's a bit more complicated than just gluing the Voyager saucer top onto the Maquis Raider. Apparently the underside of the saucer (where Voyager's secondary hull would have been glued) was cut out a bit so the top of the Maquis raider actually goes inside the saucer. The plastic is big and pretty much impossible to cut with my hand saw in vaguely the shape of the raider.

Anyway, here's what I found on Amazon:

http://www.amazon.com/Dremel-4000-6-50-120-Volt-Variable-Speed/dp/B002L3RUW0/ref=pd_cp_hi_0

This model (the 4000-6/50...whatever those numbers mean) is a plug-in, variable speed model with lots of accessories, plus the flex shaft attachment. Would this be a good buy for what I need?

Also, there's a workstation to plug the tool into so it's easier to use the flex shaft attachment while it holds the main tool in place. Is it worth getting too, or just an unnecessary extra?

http://www.amazon.com/gp/product/B0...pf_rd_t=101&pf_rd_p=1389517282&pf_rd_i=507846

 

[Gepard]

It boils down to this.

Buy one that plugs into the wall.
Buy one with variable speeds (with low RPMs).
Buy a flex shaft attachment that allows you to place your heavy dremel down. I don't care how small they are, they're all too heavy and the flex shaft attachment gives you SOOOO much more control because it's so light.
And don't skimp out on bits, sanding discs and cylinders. You'll go through the sanding bits fast.
As for the make, like any tool, money talks. Buy name brand and don't be cheap.

This is all good advice, and I'll add one thing:

If you're buying Dremel, buy an older American-made model.

Dremel used to be built in the USA and their stuff was fantastic; I have a ten-year-old plug-in model and it still runs great. A few years back, they shifted their production to China and all reports I've read are that the new units have shitty torque and burn out after a couple years of use.

If you just want a good, solid rotary tool and don't care what brand, I've heard really good things about Proxxon for hand-held rotary tools, and Foredom Electric for larger, bench-mounted applications. The Proxxon especially are competitive with Dremel on price and I believe the bits are cross-compatible; they're also better for drilling and boring, tasks where Dremel falls a bit flat. I haven't used them myself, but I know a lot of pros do and they're supposedly great.

 

[Albertese]

...

If you just want a good, solid rotary tool and don't care what brand, I've heard really good things about Proxxon for hand-held rotary tools, and Foredom Electric for larger, bench-mounted applications. The Proxxon especially are competitive with Dremel on price and I believe the bits are cross-compatible; they're also better for drilling and boring, tasks where Dremel falls a bit flat. I haven't used them myself, but I know a lot of pros do and they're supposedly great.

I have all three of these brands. Proxxon is not normally compatible with Dremel, because Dremel is SAE while Proxxon is metric (1/8" does not equal 3mm... you will spin your collet if your are miss-matching the bits; make sure your collet matches your shank). I have a Foredom that's pretty heavy duty and is fantastic for power carving wood, but is enormous overkill for plastic.

For what you're doing that Dremel you linked to on Amazon is all you'll ever need and then some. And you won't need the holder contraption. That's really for if you are gonna do more precision milling type stuff and/or drill press type stuff... but for what you're doing, you'll want to hold the handpiece anyway... this tool mount jobbie will just get in your way.

--Alex