Milling Camshafts

[NC Cams]

Note to MCGYVER re 1.5cm cam grinder:

I don't have one but there are plans published and readily available for one - there is/was a feature article in Home Shop Machinist not long ago wherein a guy MADE a bench top cam grinder for grinding model cam engines. Essentially, it is a scaled down version of a "real" rocking table cam grinder. Depending on the integrity of the profile that is concieved/designed, it would/should grind a pretty good cam - it is doing pretty much EXACTLY what our "real" grinder does albeit on a much smaller scale.

The real "secret" to grinding cams is found in how well and how accurately one generates the valve inducing motion shape. Yes, a "faceted" cam is readily makeable - we did that. When you figure out how to remove the facets so the thing does not sound like a machine gun while its running, you've LEARNED part of the secret to making a cam. As in "generate a SMOOTH, continuous shape WITHOUT steps and or faets - after all, "all you have to do is remove the facets". Really???.

Anyone who's developed a stepper based drive and who can make a smooth continuous curve should be able to do it - as in remove the facets. How we do it is/was based on the machines we used and developed our processess to work with (all servos). It was NOT easy. It took custom G and M code writing and we literatlly pay a royalty for each and every profile we cut with the software - and gladly we do so. IT was a piece of "you can't do that software" that a guy did "for grins". He grinned as much as we did when the damn program did what "experts" said could not be done.

Our cam business is essentially a boutique business that pays the bills - we have fun and we make parts. We do it for the fun of it as much as for the profit but, mostly, I do it because I wanted to learn how and I set about to do it. And did it under some prettty stressful circumstances at times and literally paid for it with my "real career" - I used to work in the auto industry until my side business became my prime goal rather than a 9 to 5 paycheck.

There are days when we'd all like to do something else. There are days when you can do NOTHING finer. When you send a cam to a client and you KNOW it is/was YOUR cam that helped them do what they did with their car, there is a sense of pride and accomplishement that is literally priceless. That sort of process hard to instill in an employee but those in whom the trust is placed and takes hold, have a similar sense of pride and accomplishment. They are and become as much of the process as any part of the operation - in fact, without them, the whole deal would fold.

Learning how to cut/make cams is just like any other technical effort. There is a well documented science behind it that has been highly published - specific references cited previously and in other postings I've made on the Zone. The question is not one of "will this guy tell us what to do" but rather how much research is a person willing to do to learn from the REAL experts exactly how to do it???

The only reason I know what I know is becasue I took the time to learn from the REAL experts who were brilliant and kind enough to write their papers and publish them so many years ago. The laws of physics and dynamics don't change - hence, the "ancient" papers are as relevant today as they ever were.

You'd be amazed at where the words "polydyne" and "Stoddard" when simultaneously Googled will take you.....

for example: http://www.audietech.com/Newsletter/CAMBiblio.htm

When you take the time to study the above bibliography, you too can take on the mantle of self proclaimed expert - every cam designer I know has or at least claims that as a level of expertise at some point in their career - and if they have made or designed a cam that works, they deserve the title....

[mikemill]

Hi Steve
Your Bugatti is a fine piece of work, did you scale and draw the parts yourself? I am interested as I am attempting to design a scale DOHC V8, hence the cam tests.

The Royal Collage of Art in London had a Bugatti exhibition about 1978, on one weekend 40 Bugatti's from a Royall to type 57 and many other examples were on display, most with engines on show, deffining good engineering as art.

Re the pics could you let me know how to load them as in my last post.

A word to NC Cams, if those with little knowledge did not attempt to learn how, without the arrogance and destain of the knowledgable it would be poor world. All your ranting and complaing ads nothing to the enlightenment and pleasure to those who paticipate in this forum,

Thanks

Mike

[stevehuckss396]

Hi Steve

1 - Did you scale and draw the parts yourself? I am interested as I am attempting to design a scale DOHC V8, hence the cam tests.


2 - Re the pics could you let me know how to load them as in my last post.

3 - A word to NC Cams, if those with little knowledge did not attempt to learn how, without the arrogance and destain of the knowledgable it would be poor world. All your ranting and complaing ads nothing to the enlightenment and pleasure to those who paticipate in this forum,

Thanks

Mike

1 - Yes I drew up the plans myself based on some photos and a 1/8 scale Pocher model.

2 - If you don't mind giving me your E-mail address, I will send some mail's with an explaination and some screen shots. This is not the place but i will help you elsewhere.

3 - Sometimes it's hard to ignore those who like to tell you they can and you cant. Try to ignore those who wont help and focus on those who want to help. That is after all why we are here.

[mikemill]

Steve
email : michaelpalmer[at]tiscali.co.uk

Thanks

Mike

[Mcgyver]

Note to MCGYVER re 1.5cm cam grinder:

...

I meant the $1.5 million dollar cam grinder reference as per the other recent diy cam making thread

Cam Grinder

[mikemill]

Further to origional post here are pics of first test cuts

Thanks

Mike

[NC Cams]

O,K. So you want to learn how to design and grind cams??? Here's how.

First it helps to understand HOW the profiles are developed. Being of an engineering background and discipline, I was able to take advantage of the math as put forth in the Machine Design articles written by Stoddard and Engemann back in 1953. The articles outlined the "polydyne" concept wherein by polynomials and dynamanics were combined to create a profile. The basic math needed to do tool paths, figure out forces and pretty much EVERTYTHING else was developed in the Stoddard articles. The articles are the foundation for most if not ALL of the computer programs EVER written for doing cams.

Too much math for you???. Spend your own money and buy canned design programs from Andrews Products.

ONce you spend you hard earned $$$ (the Andrews stuff ain't free) and get your fill of that process, get hold of the Don Hubbard manual (see prior bibilography). Don is now retired and lives in Florida. The manual is/was about $125 and worth 1000 times that in "how to" as far aa camshaft making goes. Too cheap to buy the manual??? Figure it out yourself for a lot more.

Profile creation is somewhat intutive and or hack and slash unless you have a math/dynamics background. If you have one, it can be relatively easy to "figure out" as in "engineer" valve motion. Otherwise, you can simply throw stuff around which is pretty much what the pioneers did and some guys still do today as they hunt and peck their way into camshaft history/oblivion.

Too bad you can't buy Cam Doctor's anymore but you can buy Ezcams - only about $20,000 per copy- a mandatory option when it comes to measuring/inspecting cams. These devices are to camshaft makers as "flow benches" and milling machines are/were to head porters. I bought one of these too as I was figuring out how to make cams. Some of the best money I ever spent on the process. BTW we offer the inspection service if you want your cam precisely measured and don't have the cash to buy your own device.

The 'rules" behind cam design are pretty simple. Hit stuff as hard as you can and don't break it. Make cams big in lift and duration for high RPM power and short in duration and high in lift for low RPM torque. Use low lift to reduce stress and high lift to get high flow areas and high power. The fact the the goals are mutually exclusive tends to complicate things but that's the fun part you get to work out. If you can measure other folks cams (buy or make an Ezcam), it really helps the learning process as in "seeing" what other guys do/get away with on/with their cams.

Everything inbetween is a lot of PERSONAL work and study. It is also EXPENSIVE when/if you are NOT adept at writing your own software code and/or computer programs. Frankly, if you don't know or learn the math, why bother???? It is also a bit tougher if you do not have a good math or science background. Why? because the science of cam design is just that - a science that is math and dynamics based. Without a basic understanding of it, it is like expecting your dog to type. Sort of like playing with electronincs and not knowing Ohms law....

The guys who I learned cam stuff from told me NOTHING. I had to hunt, peck and look for it in archives and manuals BEFORE the internet existed. I also had to BUY a lot of EXPENSIVE stuff to get/learn it. THis included trips to libraries, universities and basements of some pretty seedy places. Why? To figure out/learn the "secrets" of cams.

Eventually, I stumbled across a 'holy grail'. I found a guy willing to SELL me programs that would do most of the math. I eventually got him to customize some of the programs for me. These programs are still in proprietary use today - these and others that we PAID to have written and PAY regular royalties to continue their use. Aftyer all, this is my business - it is NOT my hobby. What more do you want me to convey in the way of a "how to"???? Perhaps leave the front door open to the shop after I draw you a map to the front door???? Get real guys....

Today, you can go to the internet, google "polydyne cam design" and get nearly 5 years worth of the research that I slaved thru and get it while sitting at your PC in your underwear. Nice work if you can get it. What are you waiting for???

The rest of the work - as in how to mill and machine and heat treat - I literally BOUGHT a company and PAID to learn that part of the process. I don't see anybody from Bridgeport Machines or Haas GIVING away the sourcre code to their trade secrets, do you? Should I as a cam arttisan do likewise? Perhaps when Bill Gates makes his source codes public but don't hold your breadth.

I've published the Hubbard bibliography in an earlier post. The amount of source info in this bibliography dwarfs any, no ALL of the info that I ever located in the years of searching for cam design and mfg technology. If you go to/thru the trouble to secure the articles listed in the bibliography - exactly what I did to learn the process - you too can acquire the expertise and do so in a lot less time and with less toil than I spent.

With this posting, I've showed EVERYONE where to find the info and in EXACTLY the same places I looked/learned so many years ago.

YCDBBSOYA (you can't do better by sitting you your asses) so get going and start looking for the "expertise". I've showed you WHERE and HOW to learn, now it is up to YOU if you REALLY want to GOYA and Learn. If you want PERSONAL training, that too can be arranged but at a much higher price. PM me only if seriously interested.

It is hardly a "rant" when you show people where to find info on "how to" find the answer but a good rant does not necessitate that the ranter drag someone to the answer and then rub their noses into it although that may be easier to affect. I hope that the camshaft devoltee who take the time to READ and absorb this will read between the lines - there is a LOT of VALUABLE information contained in this rant.....

[NC Cams]

MIKEMILL's efforts as pictured clearly shows that he knows what's going on. Even the profile looks like a "real" cam lobe one as opposed to a kluged up shape...

From the shapes that he's made, it appears that he's got the basics well in hand. Clearly not the effort of an inept person, rather quite the contrary.

Goes to show that you don't have to be taken by the hand and escorted to/thru the process, not in todays world with internet access to the WORLD of information.

[mikemill]

Dear NC Cams
I am flabergasted, a compliment from you re cams is praise indeed. At the risk of upsetting you any further, you are in danger of contradicting yourself.
I am just a lowly model maker, not an hard earned expert such as yourself, and I promise not to set up a cam making business next door to you !

Best Wishes
Mike

[NC Cams]

There is a fine line between offering "help" and "turing over the keys to the store". Where that line is is/can be hard to fathom - especially when you're on the other side of the line.

I too longed to have the "sectets" of camshasfts conveyed to me in "revelations". I was fortunate enough to have worked for a company where that sort of technology - cam indued valve motion - was endemic to the use of the products they were supplying. Hence, I had access to the support techonology that further enabled a devotee to learn/study camshafts. The 'revelations" came slowly and over YEARS of study thru pages of obscure and hard to find research papers.

Frankiy, the technology is well but obscurely documented in SAE and other venues. IF you know where and how to look for it, you can find the technology as well as very feww "experts" who know how to affect it. However, the "experts" are few and far between. THose who best practice the technology run their own businessess or work for the OEM's and HARDLY are in the mood so share, let alone "give" up their expertise.

The fewer still who are/were willing to "share" the information did so ONLY after applying considereable CASH therapy. They GAVE nothing!!! - they sold it and not inexpensively!!!. It is one thing to "help" a hobbyist - it is something TOTALLY different to GIVE UP the secrets to your PROFE$$ION. Literally, milling cam lobes PROPERLY out of billet is not the easist thing to do and/or master. Ask anyone who's mastered the process.

I'm sort of amazed at the attitude displayed by some of the respondants. Where is the respect for a persons trade secrets? Am I supposed to "give them up" solely to help a hobbyist??? NOBODY helped me in my quest for BUSINESS knowledge - I had to dig and pay DEARLY for it myself. It is literally one thing to "help" - it is another entirely to "spill the whole pot of beans" out in front of someone who's too lazy or perhaps inept to do the RESEARCH needed to LEARN or PAY for the the tecnology on their own.

Learning the tconology involves a LOT more than reading a paper or two and writing a few lines of code and plugging some CNC stuff together. It often takes an INVESTMENT in time and money. Guys who INVEST in their futures turn their dreams into viable businesses and success stories. Guys who dream sometimes do just that and tinker their lives and dreams away. I turned a hobby into dream into a business. The experience was priceless and what a rush. .

Whether it be for REAL or model engines, the INVESTMENT remains the same. I just took it farther and to a higher level of intensity. The effort you or anyone puts into studying the technology will turn into successful implementation of same when and if you choose to implement it. The day you turn your dream into a reality is the day you go from being involved to becomming committed.

As the efforts of MILKEMILL show, a cam shape can be milled by a neophyte. Now the real question is "will the cam generate viable valve motion???"". I've seen some pretty impressive cam lobes that do nothing more than make noise and break parts due poor dynamics.

Now that MILKEMILL has cut metal, the real FUN begins. Now he gets to see if the machining efforts created or broke any laws of physics or dynamics when it comes to moving valves. However, if you can "read" the profile and determine the dynamic signature, you should not have any "surprises" when it comes to actually running the engine.

Cutting the shape is easy - getting it to live now becomes the objective....

MIKEMILL: if you can set up a shop next door and mill cams cheaper than I, I'll pay you to mill mine. IN the mean time, there are not too many people beating down the door looking for the service nor wanting to buy the business from me. I guess we'll just have to go back to whittling on billets for the few who do want/need the service.

In the mean time, did anybody "learn" anything from any of the references posted in the thread or from any self genereated research???? Or didn't I "give up" enough information in my any of my rants???

[mikemill]

NC Cams
Thanks for enroling me into a religious order, no wonder you have no work, if you blast your customers with the same retoric as you do here.

It has been very enjoyable to exchange ideas with you, but I think we should call it quits, and get back to 'creating' cams
Regards

Mike

[Mcgyver]

I'm sort of amazed at the attitude displayed by some of the respondants. Where is the respect for a persons trade secrets? Am I supposed to "give them up" solely to help a hobbyist??? NOBODY helped me

Personally, it wouldn't much matter one way or the other whether you revealed your trade secrets, we all have limited bandwidth and cams aren't up there for me at this point in time, maybe one day but now. If you did reveal all, i don't know that I'd get it, retain it or have a use for it. My point was more, if you're just going to rant about how tough it is to learn and that you've paid your dues paragraph after paragraph why post it? imo it tends to belittle the excellent efforts put forth by some of these guys.

reread what you posted here:

Cam Grinder

you dumped all over the guy, calling what makes a 'toy', talking about how many wins you have and that you have a 'real' cam grinder.....but did you help him out or give any tips or value add? whether you want to share info/knowledge is your call, peace, but the combo of not sharing while dumping all over them as to why you know so much more is only going to discourage guys like this from posting, and think that would be a shame as i think they've got a lot to contribute.