Started practicing on some bad housings... I need a flex shaft for the dremel and a ton more practice.....

Hardest part is keeping it consistant, and I cannot keep the thing in the shape of an oval! Oh and beveling is so hard...

Get the NEW flex shaft!!!! has a comfort grip on it! very nice to work with.

Thats what I was using. I did 90% with the cylindrical one and that does not work at all on the sides...

I always wondered what it would look like if you let a special ed class practice porting a motor...heh...now i know...





Elliot have you seen my baseball?

I did get some more toys to play with https://www.nopistons.com/forums/pub...IR#>/smile.png

practice makes perfect!

That sure is a funny looking contraption.

I think it might be an awful lot easier if you got larger diameter bits. https://www.nopistons.com/forums/pub...IR#>/smile.png

you know what that might help. When I went from the cylindrical one to the cone shape it was a ton easier. I was using the wider base of the cone...

I gave up on those metal bits a long time ago. I almost exclusively used cutting disks. I did use a couple stones here and there though. I also use the sanding drums to create a nice bevel. 2mm @ 45º.

Yeah, what Tyson said.



I use an air powered die-grinder with much larger bits. Mine is 8-10 mm diameter. Goes through the housing like a hot knife thru butter. Takes less than 10 mins per exhaust port, including sanding/finishing. I use a dremel with the flexi for the final sand finish, but the die grinder I just attack it from both sides without any probs. Practice, practice, practice! Have fun https://www.nopistons.com/forums/pub...#>/biggrin.png

hahaha you newbie! https://www.nopistons.com/forums/pub...IR#>/bigok.gif

#1 sentance you don't want to hear the guy working on your motor say.....

Dremels suck for porting. I use a 1/4" die grinder with carbide bits for rough porting, and an 1/8" pencil die grinder for the detail work. 70K rpm, it doesnt overheat, and its small and easy to control.

I love using a dremel and won't waste any time trying to use a die grinder the next time I port anything. The dremel allows better control and precision and the die grinder I had was very clumsy.

Agreed, the dremel gives me all the control I want. No real need to rush it, and besides I wouldn't want to.



Sanding drums are awesome, its also a lot easier to stay even throughout the port.

With enough practice, nothing is clumsy or too fast. Ive got some new bits I need to try on the rotor housings. Those take WAY too long when you start doing exhaust ports like this.

I am porting a f-ed up throttle body and it is a bit harder than I thought, but I am starting to get the hang of it.

If your just taking away massive amounts of metal then I guess a die grinder would do the job. But in no way would I ever use it for any sorts of detail work, one mistake and you got yourself a big gouge.

Exactly!

The reason your having such a hard time is because your using the wrong tools.



You need a pneumatic die grinder and carbide burrs.

I have never even heard of a shop porting with a dremel.

rx7_re, There is a right and wrong way and the dremel is the wrong way.



Here are the links so that you can buy the right tools.

Die grinders for sale



Carbide Burrs





One good link to an idex of the different burrs. You need double cut burs for the housings and a single cut burr for the exhaust ports.

http://www.sculpt.com/catalog_98/burrs/solid/

I disagree with the dremel being bad. I use it all the time at home. When I have access to air I do use a die grinder. Both are good but both need practise and using the right bit for differant metals helps.

chuck

I ordered some burrs from enco. I have an angled die grinder that should work well.

Last night, I had my first STAB at the primary intake ports. And they turned out great. I used a 1/4" Die Grinder with cross-cut carbide bits made by Ingersoll-Rand to shape the port. I was able to work 90% of all angles with great precision. The dremel was also useful because of it's size. I was able to squeeze in the tight places to sand/polish the corners.



The two tips I can offer, which I found very effective:



#1 Control your cutting speed, to a nice slow speed. Almost to the point where you bog out the cutter when you get on it. I found doing this with a 1/4" die grinder is a bitch, On-Off-On-Off, so I used a piece of rubber coolant line to put on the underside of the lever. This gave me great control over the variable speed, and will avoid a lot of 'OH ****'s' where the cutter gets away from you. You can't get a 3 speed dremel low enough in the RPM's to cut with carbide easily. So if you buy one, the variable speed cordless dremels are awesome, but then you are stuck with the tiny bits...



#2 Shape the port at exact angles, not like you are cutting hair.. I drew the template and cut to the outer edge at a 15-20deg angle. Then I shaved down at greater angles each pass until it looked like a machine made the cuts. I found this helped a lot with port matching and precision.



If you ask me, I'd say the exhaust ports are the easiest to port. I'd keep practicing on those with better tools. Then go to the intake ports. Good Luck!



-Brad

I got to use a friends electric die grinder with a flex shaft and foot speed control. That is Super nice! Having the right bits helps a ton also. 2" bits just don't work well at all. 4-6" would be optimal.

why not adjust the air pressure going into the tool to control the

speed of the die grinder and prevent any over revving?



revvin- you can get long carbide bits for the die grinder