What's a good tool for chopping and grinding on bikes?
Up until this point I've been using an electric drill, but a drill is too large and bulky to get into tight spaces and still be precise. Quite a few frames have been doomed to the junk pile because of drill slip ups. I've looked into getting a dremel, but from what I read they aren't meant for heavy use. Anyone know of a heavier duty dremel or a similar tool that can fit into tighter spaces and yet still hold up to moderately heavy use?
A die grinder may be the tool you are looking for:
That's exactly what I'm looking for. I must have been living in a box to have never seen one of these before. Thanks.
No prob! You can get them in air-powered versions too, but cheap ones are horribly weak.
Not to be a smart-a**, but how exactly do you "chop" on anything with a drill?... Good grief, you're giving Bob Vila a headache.
Originally Posted by Bioflamingo
Now then: on to the help.
Dremels are small, but you could cut the Queen Elizabeth II in half with a Dremel and enough cutting disks.
I am not a fan of the lowest-end Dremel.
The "good" Dremel is the 4000 XPR that sells for around $80 or so, with a small kit of accessories.
For steel you will definitely want the cutoff wheel mandrels, and the variety of cutoff disks: there's fiber-reinforced disks, and two thicknesses of aluminum oxide disks (looks like red sand). Dremel part #'s 409, 420 and 426. Get them all, you're gonna need them. Also make sure you get a couple bigger silicon-carbide grinding stones (these are the "green sand" ones).
The other Dremel bits are not real useful for working with steel. The diamond-coated bits cut way too slow, and Dremels don't spin concentric enough for them to last long anyway. The sintered-carbide bits snag way too much. The helical tungsten-carbide bits throw off millions of tiny steel splinters all over you that will sting, and that you will be picking out of your skin for the next two weeks. The wire brushes are too soft to remove rust at any decent rate. The buffing wheels are only useful for cleaning up jewelry.
Get a full-face shield if you buy a Dremel, not just goggles. The little cutoff disks will bind and snap off, and send pieces flying--sometimes so fast that you don't even know it happened. You get done grinding, and when you turn the Dremel off, you see that only half the cutoff wheel is still on there.
Don't buy any cordless Dremel (or any other brand for that matter), they're very weak.
For bigger jobs there are electric die grinders, as noted. Die grinders only come with one size collet, a quarter-inch.
You will need a variable-speed die grinder to get the most use out of it because most electric die grinders are one-speed only, 25,000 RPMs, which is way too fast for many accessories. There's a couple expensive $240+ models (Makita and Bosch, I think) that have their own speed control built in, but you can do it way cheaper than that.
Go to Harbor Freight, buy their $40 electric die grinder with long shaft (part# 44141-0VGA) and also buy their $20 router speed controller (part #43060-1VGA). The speed controller will not work on any electric motor, there are some things it will not work on--bit it does work with the die grinder. So then you have a variable-speed setup, for only $60.
You can also get a 4-1/2" angle grinder at HF for $30. With thin cutoff disks, it will easily blaze through bicycle parts with a spray of pretty sparks. Even parts you didn't mean to blaze through. The "grinding" disks are a quarter-inch thick, the cutoff wheels are a sixteenth-inch thick, and each only costs a couple bucks.
(the HF speed controller works perfect with the routers and the above HF die grinder. It may work with other motorized tools, depending on exactly what kind of motor they have. I do not know if it will work with the HF 4.5 angle grinder, as I don't have one to try. I have a older Craftsman angle grinder, and the HF router controller won't work with that. You just have to try it on the other tools you have and see)
Last edited by Doug5150; 12-12-09 at 01:54 PM.
Honestly, a Dremel 300 series would work. We still have a 20 year old 395 that would work just fine...
Actually with homemade arbor it cuts nicely with angle grinder cut off wheels. Only reason I don't like it is because of the occasional odd angle, and using the wire brush attachments with a drill can sometimes be a bit awkward.
Originally Posted by Doug5150
After doing some checking around I believe I'll get a nice dremel for the hard-to-reach spots and keep using my drill for the bulk of the work. I'll be sure to mail Bob Vila some aspirin
Thanks for all the replies.