Dremel bit education

Posted by: Chisel

Dremel bit education - 08/09/12 08:54 AM

I recently bought a 200-piece dremel bit kit. I only needed the cutting disc but couldn't find it separately and bought the whole kit of accessories and bits.

When I opened it, there was no paper showing what is used for what kind of job. There were discs, brushes , bits of every shape , material, and color. So, here is my question: Is there an online guide to educate me which piece is used for what ? For example, which disc I can use to cut metal and which I should use for plastic ?

pdf files are prefferred for saving and future off-line reference.

Posted by: Chisel

Re: Dremel bit education - 08/09/12 08:22 PM

Thanks Izzy. That was informative indeed.

From your link I learned most basic stuff, and on that page a further link to Dremel website gave more details.

Posted by: Chisel

Re: Dremel bit education - 08/09/12 10:06 PM

Great. I would appreciate if you can teach me a few more things about these bits.

First, even from the Dremel site, I could not figure out which discs are cutting discs ( where it stated : only the thin edge should be used for cutting, but the flat surface should not be used for sanding - may break under pressure) and there are sanding discs. They look alike from the photos. My only possible method of differentiatin is to use the thin discs for cutting and the thick ones for sanding.

Is this correct ??

Second question , all those bits ( cutting bits, sanding bits ..etc. ) come in different colors like pink, white and grey.

What does every color indicate ?

Thanks again.
Posted by: Alex

Re: Dremel bit education - 08/09/12 11:08 PM

That disk-like looking sanding "wheels" on the chart are actually round pieces of sanding paper. Thick disks (which are usually attached to the mandrel permanently) are for grinding, not sanding.

The color of grinding stones is different because of different abrasive material used. Meaning? I'm usually just trying different stones on my projects and see how they behave at different speeds. Some are too soft, some - too coarse, you will see that at once. The strongest and sharpest grinders are greenish colored. Pink seems to be the softest. Not sure about white stones.
Posted by: RayW

Re: Dremel bit education - 08/10/12 12:01 AM

The sanding wheels are usually abrasive on one side and not on the other. The cut off wheels are uniform in texture and color on both sides. Be very careful with the cut off wheels they break easily and fly in all directions when shattered in use, so sure to wear at least eye protection if not a full face shield.
Posted by: Alex

Re: Dremel bit education - 08/10/12 12:32 AM

Yep, full face one works great! Even without shuttering they produce a lot of high flying dust and debris on high cutting speeds.
Posted by: chaosmagnet

Re: Dremel bit education - 08/10/12 12:48 AM

The white grinding stones I've had have been finer than the others.
Posted by: Chisel

Re: Dremel bit education - 08/10/12 06:14 AM

Thanks everyone. Appreciate it

I did have a few drill attachments similar to these Dremel bits but larger. Not te cutting wheell though. I have used some for sanding on some projects ( uneven edges of metals that I have cut by metal snips) but the metal object ate away the sanding stones. The metal sheet worked like a knife on the stone. LOL. Maybe I did not know the best way/position to use them.

Anyway, thanks for alerting me to use full face shield. I have one in my dad's house. I am going to bring it here first time I go there. I'll use dust mask too.

Oh, one more thing related to safety.
I have storage room fitted with ceiling-high metal shelves. Their stands are 3.0 meter (10 feet) high and I want to cut them in half. All 4 walls have these shelves but 2 walls alreasy have half-height shelf racks. In the past, when I cut the shelf stand for one wall , I had to empty the shelves on that wall, disassemble the shleves , then cut the stands in half using a hacksaw, re-assemble the lower halves and fix them to the wall. Then refill the shelves with stuff. That was a lot of work.

This time I am thinking to empty the upper shelves only ( which are almost empty anyway), remove them from the stand (leave the lower shelves intact), then cut the stands with Dremel while my son - on a ladder - holds the upper half of the stand in his hand so it does not fall on me.

My concern in this case is that maybe the cutting will produce lots of sparks and an ember may form and settle in some of the material on the shelves ( pillows, nylon bags .. etc. ) and then start a fire when we are away. This is a storage room and we do not stay there much of the time.

So, do you think that Dremel-cutting the shelves is safe enough with all that stuff on the lower parts , or do we have to empty the shelves anyway ???

Posted by: Alex

Re: Dremel bit education - 08/14/12 06:05 PM

I think you can just cover the shelves below with some fireproof tarp, as the really dangerous hot sparks from a dremel tool will fly away for no more than 3 feet in my experience. In some gentle projects I've been using a plastic bottle cut to the proper shape and attached to the Dremel thread to collect most of the dust right away.

Use large fiberglass reinforced cutting wheels if you need to cut steel for more than an inch long around especially in an awkward spot. Another option - very thin carbide wheels - they are cutting really fast at high speeds, however they are most brittle ones and can not go deep enough sometimes.

Also I would rather spend some time additionally securing stands by anchoring them to the ceiling, placing something under, or tie/clamp it down to a long enough splint to hold pieces together... as cutting with the Dremel may take quite a while, so your son may loose attention/caution. He could hold a vacuum cleaner hose collecting the produced dust instead.
Posted by: Alex

Re: Dremel bit education - 08/14/12 06:15 PM

Originally Posted By: Chisel
but the metal object ate away the sanding stones. The metal sheet worked like a knife on the stone. LOL. Maybe I did not know the best way/position to use them.

The most important parameters under you control are pressure and rotation speed. For hard metals it's better to use high speed and light pressure, cutting not through and out, but removing layer after layer.
Posted by: blueroofdesigns

Re: Dremel bit education - 08/19/12 02:11 PM

I'm so glad you like my blog post!

It took a long time to write, but I felt that the topic was worthwhile. My plan is to compile all of my Dremel-related blog posts into an eBook, but that's a while down the road.

Posted by: chaosmagnet

Re: Dremel bit education - 08/19/12 04:02 PM

Welcome to ETS!