dremel carbide bits grade/quality?

[sarepairman2]

So, I got the a few of the official dremel carbide bits (from home depot and sears), and they kick a fair amount of ass despite being pricey (8-10$ each).

I see bits on ebay that go for about 1$ a piece (in kits).

What is the top, low and midrange of small high speed tungsten carbide cutters?

i.e. this is what I have (10$)
https://www.dremel.com/en-us/Accessories/Pages/ProductDetail.aspx?pid=9901

this is what I can get for 10%  of the price on eBay (~1.5$ each)
http://www.ebay.com/itm/New-20pcs-Tungsten-steel-Solid-Carbide-Burrs-For-Dremel-Rotary-Tool-Drill-Bit-/171352723454

I am willing to pay more for good quality tools, but is there a difference? cheaper ones use a different alloy (mystery meat) or something (tolerances, internal stress,?)?

[PTR_1275]

Can't say for certain about the carbide bits, but the wire brush attachments from dremel are expensive (~$10 each) and I was quite dissapointed how quickly they would lose theirs bristles. I ended up buying 20 eBay ones for less than $5 delivered. They don't last quite as long as the dremel ones, but considering how many I got, I don't care.

I have bought some of the dremel toothed cutting bits before and had mixed results, some last, some don't.

[sarepairman2]

I imagine you used the brush wheel at a much lower velocity then the dremel is capable of right?

I was thinking about this too (I got the dremel accessory kit). My dremel can go up to like 25k RPM (battery powered).

A bench grinder that a wheel is typically attached to goes to like, 1800 or 3600 RPM). Even an angle grinder is only like 5k.

I imagine running a brush wheel at 30,000 RPM is maybe not the best idea and that the brushes should be used at the lowest speed setting.

[PTR_1275]

My battery dremel goes to 10,000 rpm and most of the time I use it on about 7 or 8,000. My mains powered dremel a don't get used much, but I don't take the brushes above 10,000rpm. Running them at 30,000 rpm would be asking for trouble for sure.

[Muttley Snickers]

I have a collection of Sutton carbide burrs and a couple of other cheaper sets from overseas mainly larger sets for the die grinders and milling machine, can’t say that I have ever bought Dremel branded bits simply because they are rather expensive down here and Sutton is known quality for not much more.

The other night I was drilling out some rivets and was trying to drill with the smallest possible drill bit I could get away with so as not to mark or damage the metal enclosure, anyway the rivets wouldn’t let go and I didn’t want to use a lever and couldn’t find the tool box with all the Sutton and other burr sets so resorted to some other shitty bits that come in a 110 piece variety set.

My normal routine in this scenario is to use a Dremel with a ball nose burr and route out the inside of the rivet in a circular motion just below the height of the enclosure lid, I went through 3 cheap burrs just on these 8 aluminium rivets as you can see in the picture below, some of the sets from overseas can be very good value but the ones in those lucky dip kits are utter garbage.

I'm currently getting a list together for stuff I want to order from Bang Good and these listed below will be included, never dealt with them before so I hope everything will be ok.

Burrs
http://www.banggood.com/10pcs-18inch-Tungsten-Carbide-Cutter-Rotary-Burr-Set-Cnc-Engraving-p-934871.html
Blades
http://www.banggood.com/6pcs-HSS-Circular-Saw-Blade-Cutting-Disc-Set-For-Rotary-Tool-p-934464.html

[robrenz]

IMO don't waste any money on anything but Tungsten carbide. "Tungsten steel solid carbide" does not make any sense. I think it is Chinese for crap steel. If what is pictured is carbide I will eat my hat.

These are all good links to carbide burs. From my experience Dremel are overpriced for average quality.
https://www.zoro.com/search?q=&categoryl2=Carbide+Burs&categoryl1=Knobs%2C+Handles%2C+Workholding+%26+Machine+Tool+Accessories
http://www.mcmaster.com/#burs/=11ivyt3

http://www.use-enco.com/CGI/INSRAR?PMSECT=0000000547
http://www.gesswein.com/c-80-carbide-burs.aspx

[IanB]

I imagine you used the brush wheel at a much lower velocity then the dremel is capable of right?

I was thinking about this too (I got the dremel accessory kit). My dremel can go up to like 25k RPM (battery powered).

A bench grinder that a wheel is typically attached to goes to like, 1800 or 3600 RPM). Even an angle grinder is only like 5k.

I imagine running a brush wheel at 30,000 RPM is maybe not the best idea and that the brushes should be used at the lowest speed setting.

I suspect the important factor is the linear speed of the bristles contacting the work.

Suppose a bench grinder is running at 3600 RPM and the brush wheel has a diameter of 4 inches, then the outer edge of the wheel will be traveling at a certain speed, call it V. This speed will determine how effective the brush is.

Now imagine a small brush wheel on a hand tool like a Dremel. Perhaps it has a diameter of 1/2 inch, which is 1/8 of the big wheel. If we want the outer edge of the small wheel to be traveling at the same speed as the big wheel, the small wheel will have to be spinning eight times as fast, or 8 x 3600 = 29,000 RPM. So in fact, running it at 30,000 RPM is not necessarily a bad thing.

Of course, if you want the action of the brush to be less aggressive and more controllable, then it doesn't hurt to slow it down.

The other thing to note, of course, is that if the contact speed is the same on the small wheel and the big wheel, then the wear rate of the bristles will be the same. Since the big wheel has much longer bristles it can absorb much more wear than the small wheel before it starts to get noticed.

[Rick Law]

I was at a high-school robotics workshop as adult monitor and I ended up helping.  We used the Dremel brand carbide cutting wheel to cut some 3/8" steel bolts.  The cutting wheel is just a bit over an inch in diameter.

We put on a new wheel when we got started but I had to change wheels right after we started the 3rd bolt.  I know the carbide wheel was suppose to rub away as it cuts, but I was amazed at how fast the wheel was grinding away!  I remember that well since it was late, stores were closed, and I was very concerned that we can't get all 8 bolts cut before I used up all 4 cutting wheels. 

Those were expensive and (fast consuming) consumables.

[senso]

I have 3 boxes of varied size/format of those ebay special tungsten, and its much, much better at grinding aluminium and cast iron than the Dremel branded bits/burrs are, a long long time ago(about 6-7 years), I could go around a cylinder(two stroke cylinder) with on original dremel burr and do what I wanted to do, then the burrs started to be of less and less quality and I couldn't even finish an exhaust port, tried the ebay tungsten bits, and I still have the first box that I bought, infact, only one burr is missing(lost it).
They are not pro grade tools, thats for sure, but for home use they put dremel branded ones to shame.

[staze]

Harbor Freight sells packages of the tungsten carbide drill bits. I'm pretty happy with them...

[KL27x]

IMO don't waste any money on anything but Tungsten carbide. "Tungsten steel solid carbide" does not make any sense. I think it is Chinese for crap steel. If what is pictured is carbide I will eat my hat.

Thanks. You know I was thinking the same thing. But I was too lazy to look it up.

I just buy stuff on Ebay or Amazon. I have no brand loyalty. But I have noticed a big difference is the sharpness of different brands of carbide endmills. My Niagara endmill could probably draw blood just handling it, if you're careless. I haven't used it much, yet, so I can't say if it's going to actually last.

I was at a high-school robotics workshop as adult monitor and I ended up helping.  We used the Dremel brand carbide cutting wheel to cut some 3/8" steel bolts.  The cutting wheel is just a bit over an inch in diameter.

We put on a new wheel when we got started but I had to change wheels right after we started the 3rd bolt.  I know the carbide wheel was suppose to rub away as it cuts, but I was amazed at how fast the wheel was grinding away!  I remember that well since it was late, stores were closed, and I was very concerned that we can't get all 8 bolts cut before I used up all 4 cutting wheels. 

Those were expensive and (fast consuming) consumables.

I think you're talking about something else. Carbide bits do not wear away, even cutting hardened steel, unless you're doing it wrong. Sound like you're describing an abrasive cutting disc. Yeah, if you need these things (I find them very handy), you can buy them in bulk packs. 

[Rick Law]

...
...

I was at a high-school robotics workshop as adult monitor and I ended up helping.  We used the Dremel brand carbide cutting wheel to cut some 3/8" steel bolts.  The cutting wheel is just a bit over an inch in diameter.

We put on a new wheel when we got started but I had to change wheels right after we started the 3rd bolt.  I know the carbide wheel was suppose to rub away as it cuts, but I was amazed at how fast the wheel was grinding away!  I remember that well since it was late, stores were closed, and I was very concerned that we can't get all 8 bolts cut before I used up all 4 cutting wheels. 

Those were expensive and (fast consuming) consumables.

I think you're talking about something else. Carbide bits do not wear away, even cutting hardened steel, unless you're doing it wrong. Sound like you're describing an abrasive cutting disc. Yeah, if you need these things (I find them very handy), you can buy them in bulk packs.

Possible that I misread the disks.  It is also possible it was a fake, I didn't buy them so I don't know if it was a $2/100 bag from somewhere.

[TheJay]

Whilst I realise this is an old thread, it still has value. What are people's experiences now of tungsten carbide burrs from eBay and is it worth looking at Titanium Aluminium Nitride Coated Carbide for cast iron and stainless steel?