X-Head Porting....

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Well, you are doing it for a living and I'm not. If it takes me a little longer, so be it. My old worn out air grinder has less torque at part throttle than my electric setup. I will never be the porter a lot of you guys are, but I will keep trying.

I am about to try and save a set of procomp heads that a previous owner went wild with a grinder on. I should send them to the scrap yard, but they are all I have to work with. So, I will do what I can.

I meant no offense , was just sharing what my experience was. It takes what it takes-no matter who you are-ROI has many variables. J.Rob
 
Hooked it up, doesn't really go variable; but by being able to quickly turn it on and off with the foot pedal will allow me to dictate the speed of the bur better, kind of like my dental handpiece

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I meant no offense , was just sharing what my experience was. It takes what it takes-no matter who you are-ROI has many variables. J.Rob
This is the truth, I used air for years and got sick of the hassle and now use a makita wide open all the time, it just works for me. I will "finish" with a air grinder if need be.
 
Hooked it up, doesn't really go variable; but by being able to quickly turn it on and off with the foot pedal will allow me to dictate the speed of the bur better, kind of like my dental handpiece

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Your work is looking very good. Better than I can do. I've never had any skill porting.
 
The first......”porting”.......I did was on some 906 heads.
I had no idea about what I was doing .......at all.
This was in the mid-80’s.
I used an air grinder powered by a 1hp craftsman compressor.
Yeh......... the grinder speed wasn’t very fast.
And I was using “stones”.

I barely even scratched the surface on those heads....... I don’t think I hurt them any, but in hindsight....... what I did was a waste of time(other than to get my feet wet with doing that type of work).

Since that time I’ve learned that on most stock heads........ knowing where to do the first grinding can pay nice dividends for fairly minimal work....... and that after the initial first work is done, the flow vs time spent porting is a pretty steep curve of diminishing returns.
 
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The first......”porting”.......I did was on some 906 heads.
I had no idea about what I was doing .......at all.
This was in the mid-80’s.
I used an air grinder powered by a 1hp craftsman compressor.
Yeh......... the grinder speed wasn’t very fast.
And I was using “stones”.

I barely even scratched the surface on those heads....... I don’t think I hurt them any, but in hindsight....... what I did was a waste of time(other than to get my feet wet with doing that type of work).


LOL...sounds like how I got my start. Funny thing is, I quickly realized that porting is like racing. If you race long enough you WILL break parts, you WILL crash and you WILL spend money. The statistics say that all will happen.

If you want to port heads, you WILL make mistakes, you WILL put holes in heads and intakes and there ain’t a thing you can do about that, unless you are some guru who gets a pallet of castings to work with and you can cut up the heads and see that water and such and you WILL spend money.

That’s the way it works. I know a guy who is much better at porting than I am, but he was so afraid of putting a hole in something he compromised too much. And if he did put a hole in something, it was literally DAYS of depression, self doubt and mentally beating himself into the ground to the point he would want to quit doing it.

I was driving truck in 1997, because the boss we had decided I was a bad employee and fired my *** so I had to work. And I needed my new tunnel ram ported. So I asked him to do it as I was too busy. He called me several days later fully depressed because he put a hole in the manifold. It wasn’t big, so I filled it it, added some weld in the rest of the places where he would blow a hole in it and it was no big deal.

But for him, it was like he trashed the intake. Some guys never get around that thinking and it makes them not as effective doing port work.
 
I'm going to try and work on an intake tomorrow. Probably right after I shampoo the carpets and temporarily fix the door striker on the drivers side...
 
Ok. Now I'm starting to get pissed... these burrs are 15-20 dollars each... bent one last week, one broke last week. Today put one in the grinder and it instantly bent when I first pressed the foot pedal, tried again and same thing to the 2nd one. Thats 4 burrs and roughly 60 bucks down the drain. I tried to shorten one and its still not spinning straight in the regular hand drill...

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Not to be too blunt........ but that’s part of the learning curve.
Knowing what approach/tactic will end up with those results.
That happens a lot less with shorter shanks.

You should try the air again, and turn down the regulator on the compressor pretty low(tank pressure high, line pressure low), which will help stabilze the speed fluctuations.

Many years ago I bought a cheap single stage “5hp” compressor($399 from Harbor Freight in 1993).
Maxed out it would go 115psi.
I put a regulator on the outlet and set it at about 50psi.
When I was doing the heavy material removal....... it would run non-stop.
I ported a lot of heads that way.
I still have it in the shop as my back-up compressor

At 50psi, the grinders generally don’t have enough torque to bend the shanks. They just stall out.
 
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Not to be too blunt........ but that’s part of the learning curve.
Knowing what approach/tactic will end up with those results.
That happens a lot less with shorter shanks.

You should try the air again, and turn down the regulator on the compressor pretty low(tank pressure high, line pressure low), which will help stabilze the speed fluctuations.

Many years ago I bought a cheap single stage “5hp” compressor($399 from Harbor Freight in 1993).
Maxed out it would go 115psi.
I put a regulator on the outlet and set it at about 50psi.
When I was doing the heavy material removal....... it would run non-stop.
I ported a lot of heads that way.
I still have it in the shop as my back-up compressor

At 50psi, the grinders generally don’t have enough torque to bend the shanks. They just stall out.

Thanks, I'm just frustrated.

This is with the electric grinder hooked up to the foot pedal. Ill look into a pressure regulator and shorter air hose.
 
Thanks, I'm just frustrated.

This is with the electric grinder hooked up to the foot pedal. Ill look into a pressure regulator and shorter air hose.
See now, my theory of operation is just the opposite. Those bits are meant to be run at high RPM. High RPM and little bites, always moving in the same direction as the bit rotation. Sure I slow down but thats when the thing bites and does the wallowing bounce act. I don't have much experience with the long bits or even porting for that matter, but I have put a lot of miles on die grinders working in the collision repair industry. I bet they told you the same thing about grinding on teeth. In the end it's whatever works for you and failure is just another word for experience. Gotta keep a mindful eye on that grip too.
 
See now, my theory of operation is just the opposite. Those bits are meant to be run at high RPM. High RPM and little bites, always moving in the same direction as the bit rotation. Sure I slow down but thats when the thing bites and does the wallowing bounce act. I don't have much experience with the long bits or even porting for that matter, but I have put a lot of miles on die grinders working in the collision repair industry. I bet they told you the same thing about grinding on teeth. In the end it's whatever works for you and failure is just another word for experience. Gotta keep a mindful eye on that grip too.

Yea I dont know if its the bits or the grinder. All of the bits bent without me even touching the head. Literally within a millisecond of me turning the grinder on by pressing the pedal the long shank burrs bent... I know if the bits are even a fraction off balance or fraction not straight it could cause them to bend but for 15-20 bucks a burr bit from the industrial store i would assume they'd be good bits... maybe not.

I'm ordering some 1/8 short shank bits to try with just the electric grinder. 15 bucks for 6 from Amazon, whats the worst that can happen lol... otherwise my porting days may be :icon_fU:

As for grinding teeth, my burrs can run at what ever speed i want them too, for smoothing walls and floors I usually run them at low speeds between 1500-15000 rpms, for taking a lot of material away I go at 200k rpms.
 
I think 20 bucks is cheap material. I've never bent a bit but I buy high dollar stuff. The material should be so hard that it breaks before it bends. They must be friction welding carbide tips onto a cheaper shaft material is my guess. Don't get frustrated. Time for a break though.
EDIT: I guess 20 bucks is the going rate for a good bit. It's been a while since I have needed a new one.
 
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I only have one burr that’s solid carbide.
It’s a 1/4” short tree shape.

Every other one I’ve ever bought was a carbide attached to what appears to be a stainless shaft.

If they’re bending just by hitting the switch...... perhaps there is some runout in the collet.
 
I only have one burr that’s solid carbide.
It’s a 1/4” short tree shape.

Every other one I’ve ever bought was a carbide attached to what appears to be a stainless shaft.

If they’re bending just by hitting the switch...... perhaps there is some runout in the collet.

Possibly there is some runout in the collet from when the larger bur got stuck and broke a bit. Its weird though because I ran 2 other bits in the drill and those spin just fine.

Let's just chalk it up to my luck. I'll see how my cheap 1/8 shank burs do tomorrow.
 
I’ve heard of people breaking/damaging burrs using electric grinders when the burr gets pushed into, or sucked into an area of the port where it wedges itself in tight....... and the inertia of the heavy(compared to an air grinder) armature just won’t stop as fast as the burr does.
Then, you often get broken teeth, a bent shaft, or the burr itself just snaps off the shaft.

The only time I’ve ever used the typical
“Electric die grinder” is if I’m tweaking something at someone else’s shop.
To me, they’re very difficult to use for porting.

If I happen to get a burr stuck in a crevice in a port somewhere with an air grinder....... it just stops turning, and there is no drama.
 
Frankly, the bent one doesn’t look like there would be enough mass in the burr to be able to bend the shank like that...... unless it was soft.

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All the burrs that have bent have bent exactly the same as that one on the left.


That is uncontrolled RPM and it’s why I don’t use an electric grinder because you can helicopter a burr right quick, just like that.

I found the same thing you did, in that the foot control doesn’t have enough control. It’s like trying to grind with a toggle switch.

Air is a PITA, but once you get a way to control air speed it’s easier. And I can use an electric grinder, I just don’t like it as well.

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You can see the little lever that controls air speed. I had a round one, but it wore out and that was all I could find. If I’m not careful I bump it and either **** the air off or it goes WOT. So I have to be careful.

Regardless of air or electric, you need some way to control speed that isn’t a toggle switch.
 
That is uncontrolled RPM and it’s why I don’t use an electric grinder because you can helicopter a burr right quick, just like that.

I found the same thing you did, in that the foot control doesn’t have enough control. It’s like trying to grind with a toggle switch.

Air is a PITA, but once you get a way to control air speed it’s easier. And I can use an electric grinder, I just don’t like it as well.

View attachment 1715676216

You can see the little lever that controls air speed. I had a round one, but it wore out and that was all I could find. If I’m not careful I bump it and either **** the air off or it goes WOT. So I have to be careful.

Regardless of air or electric, you need some way to control speed that isn’t a toggle switch.

I have 2 air die grinders that look just like that, easy to control speed but again not enough air to run them a long time...
 
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