KOR Banshee Head Video

dksix

Member
Apr 16, 2012
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North East Tennessee

In the video you said that you set the spindle slightly off square with the bed. Could you explain this a little more? I would have thought that the bed being square with the head would be a must. I looks like this would leave a slight concave on the head instead of it being flat. Thanks for the video, having the machine unsquare is something I would have ever thought of.
 
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Its offset is .0005 from one end of the circle to the other. That’s about 1/6 of the thickness of a hair. The offset prevents the cutter from taking the same cut on both sides and back cutting. It’s a very common practice.
 
I asked in the other thread how flat a head needed to be but was nevered answered. So having the hard with a half of thousandths concave will be fine? I've seen debates on how rough the sealing surface of heads should be, some like a little texture to hold the gasket and some say the roughness promotes leaks. Like I said, my machining isn't from an engine shop. I guess a step of. 0005" would be harder to seal that a concave going from the center out. Once again, thanks for taking the time to put up videos and posting. Its good to having an expert's advice.
 
The offset is cosmetic only, and like Ken says, commonly done.
The flycutter looks to be over 8" diameter, 0.0005" offset from side to side, the head is only 3-4" wide.
Total concave from center to edge of an 8" cut will be 0.00025"
Total concave from center to edge of a 4" wide head will be less than 0.000125".

That gentlemen, is negligible! :)

The Blaster manual (pg 2-4) says 0.0012" for a Blaster head.
Composite gaskets can take up much, much more.

Nice vid!
 
Thanks, Best. That's what I didn't know. I never thought of looking in the book, lol. So even cutting one with a small cutter, like civic was doing, could easily cut the head to well within tolerance. I only have a 1.5" cutter and if i did one I'd have to make multiple passes but I know I can cut with it with less than .001 steps.
 
Yes, and the back scratches will not hurt a thing, Ken wants a professional appearance to help sell the product.
Surface finish is not too critical in my opinion. Gasket condition more important.
I've hand filed and sealed 2 stroke heads with just sealer, no gasket, on occasion.

The Blaster is super easy to check for head gasket leaks.
You can feel them with your hand while revving the engine.
Unfortunately this does not work with watercooled or shrouded engines.
Love these Blasters!

Steve

Hand filed headgasket surface:
562243_10150994303620803_1472451543_n.jpg
 
Thanks, Best. That's what I didn't know. I never thought of looking in the book, lol. So even cutting one with a small cutter, like civic was doing, could easily cut the head to well within tolerance. I only have a 1.5" cutter and if i did one I'd have to make multiple passes but I know I can cut with it with less than .001 steps.

I would like to point out that as long as you can hold it to within ±.002" you can lap that much back out.

The real advantage to a large diameter flycutter like the one in the video and "cocking" the head on the mill is that it doesn't backcut so the finished cut is ready to use. This is especially important on a larger scale than we're talking. A blaster and banshee head can both be finish lapped to flatness. It applies more to say a Jeep 4.0 I6 engine where one would search for quite some time to find a machinist stone and piece of sand paper large enough to lap that..... One would HAVE to set up the machinery to take it in one continuous swipe with no backcutting.
 
Close enough isn’t in my vocabulary. The processes we use are of professional quality and profitable at the same time. I completely agree that you can hand file a head, or mill one with imperfections and do the finish work by lapping. This is not the philosophy we use at KOR. I follow the example of the Late Great Henry Ford in his never ending endeavor to bring lean manufacturing to the automotive industry. He said “I will add no process that doesn’t add value to the product”. Pretty basic fundamentals. The goal at KOR is to constantly find ways to improve our processes without sacrificing quality. This is how we keep our customers prices down and maintain quality surpassed by no one. There are many ways to skin a cat; some leave more fur than others. Before I went full time at KOR, I ran an aircraft assembly shop with 40 employees. My people made Textron bomb triggers, cable assemblies that open the launch doors for nuclear weapons, armor for the Humvees in the Middle East, and over 300 different parts for the C130. A pilot got his wing blown off in combat in his AT- Warthog and I was so proud to see that he made it back alive using the cable and shivs that my crew built. If I seem anal with all of this grinding, filing, bird sh*t welding and sub standard machining…………………………Blame it on ISO, AS standards, and The FAA. God Bless America!!!!! I’m going to fire up the Stratocaster and rip the Star Spangled Banner for Jess. Be back soon.
 
Close enough isn’t in my vocabulary.

Ken, I meant no disrespect with the term close enough. That's why I asked my question. Tilting the head would cause a slight concave in the surface, I was just asking you to explain why. After your response, I understood you were saying the concave was preferred to the rough finish that would be left if the tool was allowed to back cut. I'm sorry if you thought I was trying to pick your work apart, that wasn't my intent.
 
Close enough isn’t in my vocabulary. The processes we use are of professional quality and profitable at the same time.

As someone selling a product, I'm damn glad you have that philosophy Ken.
Heavens knows, industry needs more of that!
We wouldn't have so many recalls and defective products and services if we did.

As someone who is not selling anything, I can afford to put innovation, expediency and unorthodoxy ahead of convention.
I am glad you stick to quality and known reliable processes.

I completely agree that you can hand file a head, or mill one with imperfections and do the finish work by lapping. This is not the philosophy we use at KOR.

Nor should it be, and good that you are here to point out how it should be done, but should you be decrying the "Backyard" way, other than you don't do it?

There are many ways to skin a cat; some leave more fur than others.

(I love this quote!) True enough! But if these guys cannot get access or afford to have a head milled to correct quench, you are not going to scare them off of hand filing are you? While you may not feel comfortable encouraging it, may never do it in your own shop, it is an expedient for a 16 year old to learn the effects of quench and the skills of filing and lapping. He may just be driven on to become a top rate machinist later in life. I was.

Before I went full time at KOR, I ran an aircraft assembly shop with 40 employees. My people made Textron bomb triggers, cable assemblies that open the launch doors for nuclear weapons, armor for the Humvees in the Middle East, and over 300 different parts for the C130.

Well, if we are spilling our CV here, I might have been a guy in the back of one of those C130s many years ago. Glad as hell they were so well made. I also got on a project back then to improve the Elcan rifle scope because I knew enough about them to modify mine with a rubber band to win national marksmanship competitions. I am a certified machinist and millwright, electrician, electronics tech and ASQ certified Quality Tech, so I do know about ISO9000 and AS9000 standards and appreciate their importance.

If I seem anal with all of this grinding, filing, bird sh*t welding and sub standard machining…………………………Blame it on ISO, AS standards, and The FAA.

I have changed jobs quite frequently over the years, but currently I am responsible for the immediate machine reliability of a factory employing over 1200. I am not an engineer, but in the past it was my job to get the engineer's projects to actually work. When the first Iraq war broke out, I was given the task of immediately modifying a machine to raise our production of armoured vehicle tires tenfold, and given a team of tradesmen and engineers to accomplish it. We did it, in part because of my ability to lead from the front, and gobby stick weld and hand file prototypes up in minutes to test an idea when it would have taken days to get a prototype done through "proper" channels, to "proper" standards. Be sure that in the end, things were tidied up to proper standards. My point is that there is a place for expediency.

If you need to change out a ring and pinion on a Dana 60, I know the right way to do it. If it needs to be done 20 miles back in the woods and the only tools you have are wrenches and a hammer and cold chisel, I can still do it. If you need to rely on a piece of machinery in a remote setting, guys with my adaptive skills, backyard/barnyard/3rd-world/outside-the-box skills are invaluable. They learn them by using their hands and their brains from an early age to accomplish things that others feel are impossible for the average mortal. These are the Henry Fords and John Brittens and Burt Munro, and untold Chinese entrepreneurs who are building factories on the fly to sell cheap to the world. They are not held back by convention.

God Bless America!!!!! I’m going to fire up the Stratocaster and rip the Star Spangled Banner for Jess. Be back soon.

I think we should also say a little prayer to encourage a bit of grinding, filing, bird sh*t welding and sub standard machining along with good old American ingenuity so that we have a generation that can think outside the box enough to get this once mighty economy going again. It starts at home.

If we all just follow the leader and try to buy our way to success, we will be following the Pied Piper into the Yangtze River. Gotta start learning to think for yourself, work to get results, not just phoney bragging rights and inflated lists of mods. Money may get you there, but brains, honesty and work are the best route. Lessons I learned hotrodding machines got me where I am today.

Ken, you are a Godsend. Thank you for your videos and your advice and just plain doing things right. From what I see (and I have a good eye) you are a top notch operator. No one starts that way. Just have a little tolerance for the guy looking to learn his way up on these Blasters.
 
I can agree there is more than one way to do this. But If you pay a "professional" to do the work you expect and should get professional results in a timely manner.

I have thought outside the box, spread the love, save a little here and there, and was dissatified with the outcome. I then had to pay more to have it fixed properly by a professional. So did I really save anything? No, cost me alot more time and a few more dollars!

For my atv work I will stay in the box. Pay the extra- and get professional quality work the first time everytime!
I don't understand why anyone would not want "professional results" when it comes to machine shop work! Saving a few dollars isn't always the best thing to do.

The real problem is most of the sh*t starters have never even had work done by Ken.
May know them personally but like to jump on the bashwagon. We know how it works, been here long enough to know this person calls this person and so on, then we have a war.
Now about the backyard mechanics (me), No doubt when your in the woods you improvise but we aren't talking about the woods here, and we all have at one point in time improvised on the trails!

Lastly, use who you want for your work, But your a fool if you don't choose KOR!

Ride hard! Drink koolaid!
 
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I can agree there is more than one way to do this. But If you pay a "professional" to do the work you expect and should get professional results in a timely manner.

I have thought outside the box, spread the love, save a little here and there, and was dissatified with the outcome. I then had to pay more to have it fixed properly by a professional. So did I really save anything? No, cost me alot more time and a few more dollars!

For my atv work I will stay in the box. Pay the extra- and get professional quality work the first time everytime!
I don't understand why anyone would not want "professional results" when it comes to machine shop work! Saving a few dollars isn't always the best thing to do.

The real problem is most of the sh*t starters have never even had work done by Ken or James! May know them personally but like to jump on the bashwagon. We know how it works, been here long enough to know this person calls this person and so on, then we have a war.
Now about the backyard mechanics (me), No doubt when your in the woods you improvise but we aren't talking about the woods here, and we all have at one point in time improvised on the trails!

Lastly, use who you want for your work, But your a fool if you don't choose KOR!

Ride hard! Drink koolaid!


I don't drink Koolaid but the quote is sig worthy.
 
Slickerthanyou, I didn't start this thread to start sh*t. Asking why he titled the head was a legitimate question. I wanted to know why. If i were going to hire engine work done, KOR is who it would be. With the same respect I asked the question. I didn't say he was doing it wrong or that he had ruined the head, I assumed he knew what he was doing and wanted to understand why. Cutting with the milling head tilted does cut a concave, not perfectly flat. He explained that the concave was insignificant and that he did it for a better surface finish, I understood. Its that simple, no sh*t was meant to be started.
 
Slickerthanyou, I didn't start this thread to start sh*t. Asking why he titled the head was a legitimate question. I wanted to know why. If i were going to hire engine work done, KOR is who it would be. With the same respect I asked the question. I didn't say he was doing it wrong or that he had ruined the head, I assumed he knew what he was doing and wanted to understand why. Cutting with the milling head tilted does cut a concave, not perfectly flat. He explained that the concave was insignificant and that he did it for a better surface finish, I understood. Its that simple, no sh*t was meant to be started.

That wasn't directed to any one person!

Blasterforum History lesson:

Way back when there was a handful of builders on this site, all had customers from different places, some did great work, others ripped guys off, some contracted out work, all wanted your money however! Then along came Ken, talked no bullshit, gave precious secrets out, made videos (still to this day), helps the DIY'rs out even though his livelyhood is made this way.

Ended up cornering the blaster market and stepping up on the banshee market already been doing 4-stroke work -due to his Professional work and the BEST outstanding support and customer service in this country and the others!

Now all the followers of those others have attitudes with any of us who use KOR, support KOR, because he put a hurting on thier wallets. But they will use the info Ken gives and turn around an bash him and his customers everytime we suggest him.

KOR is the best, In quality, price, support and friendship! I really don't care about the others! Kens work speaks for itself!


One last thing the Koolaid is Killer!
 
/\ whats with the molson twins talking bout kool-aid vs. powerade ? :)