I've got a few different style aluminum grinding burrs for my air grinder that I've been using to port aluminum cylinder heads but they just arent long enough to fully reach down into the port floors on some of the heads I do and I have leaving a bottleneck.

anyone know where I can get grinding burrs from with longer shafts on them?

also, my air regulator broke on my air compressor so my air grinder spins at full speed all the time. while I've gotten used to it and it doesnt bother me much anymore I was just curious.....can one of those craft style dremels from wal-mart cut aluminum decently or do I need to use lots of "hand pressure", etc??

like does it physically have the torque to cut at will or will it slow down, etc??

I tried one of those ebay-special die grinders and that thing was out of control lol.

 

huh?

 

I would stick to the air die grinder for now in your case. The only electric die grinder I would personally buy for porting heads is one with a foot pedal control and has the motor hanging from an above location. Thos are $200+ though.

As for bits, you could buy them through places like Summit or Jegs, or check out http://www.carbidebur.com . I've bought a few things from them.

 

eastwood also carries 6 inch carbide burrs.

http://www.eastwood.com

 

this is who i use and have had great success with them

http://ruffstuff.com/

 

I have used americancarbide.com 3 times. Fast shipping, good selection and inexpensive

 

I'm sure you could find something at Macmaster-Carr.com also...

 

Mondello

they have quite the assortment

 

thanks for the responses guys. I used that first site since it had a 9" extension arm for the burrs that way I can still use the ones I've got and not have to order longer ones yet.

I guess we'll see how that works out heh.

 

im shocked you paid 38$ for that extension. i have the same one i got for 10$. and it wont do too well with porting tight spots in heads because the chank is a lot wider than your bit. you need to get 6" porting carbides if you want to do a good job. and i have the HF electric die grinder with a variable speed adapter for routers, and an air die, and they both are needed IMO...
rockets board has a ton of thread on this same subject too.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by hybridvteceg &raquo;</TD></TR><TR><TD CLASS="quote"> i have the HF electric die grinder with a variable speed adapter for routers, </TD></TR></TABLE>

Explain the speed adapter part. I also have the HF electric dye grinder, for $40 its awsome.
And mcmaster carr does have quite a selection of carbide bits

 

i didn't read the previous posts but you can use a regular carbide burr on aluminum and summit sells some with 6" shanks, but when using on aluminum be sure to have it constantly lubed up or else it will clog the burr.

 

not all do that

 

If your grinder only spins at full speed , don't use any long shank bits in it as is very dangerous. As soon as you get the bit stuck it will bend and whip around before you can blink.

Yes heavy duty dremel works ok, that is the one that has the flex shaft with the 1/4 hand piece. It might be special order.

 

if your burrs are good you should need basically no pressure applied, just slight. i can't believe your air grinder dosen't have a variable speed on it. Go get a cheap one (inexpensive) from home depot or lowes, i got my CH straight die grinder for 20 bucks or so. Then don't worry about the regulator, or an even better idea, fix it. You really don't need much speed on the burrs, i found out it's not only easier to control but cuts much better at slower speeds

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by new2novas &raquo;</TD></TR><TR><TD CLASS="quote">if your burrs are good you should need basically no pressure applied, just slight. i can't believe your air grinder dosen't have a variable speed on it. Go get a cheap one (inexpensive) from home depot or lowes, i got my CH straight die grinder for 20 bucks or so. Then don't worry about the regulator, or an even better idea, fix it. You really don't need much speed on the burrs, i found out it's not only easier to control but cuts much better at slower speeds</TD></TR></TABLE>

it did have a variable speed but it broke somehow and I'm just too lazy to take apart the grinder and find out what is stuck or stripped on it. It sorta locked open at full throttle when I bounced off a corner inside an exhaust manifold a month ago.

I've gotten used to it now so it actually doesnt bother me much.

Oh, and I got the extension the other day and have had no problems with it so far reaching down inside the manifolds or head ports.

I've had to start taping a flashlight to the other opening so I can see what I'm doing but everything is working well *knock on wood*

heh.

On another note I did grind through a port floor on a practice head when I was getting used to the extension and trying to tig in the very middle of a port is NO fun!!

 

i would get SOMETHING fixed so you have some kind of speed control, but if its ok with you, then i guess leave it.

I think they have some kind of epoxy you can use on the port wall, have fun filling the hole with a tig