CAM Calculations for single overhead cam.

[marshengnz]

We are limited here in NZ to existing CAM profiles from a few cam grinders. No CNC chaps here for Honda's !!!!

Does someone have the maths skills to calculate the valve movement transferred from the CAM through the rockers ? It's not rocket science but I'm getting too old for this now.  

I would like to design my own cams cause I have a spare CNC lathe that I can convert to a CAM grinder.  

Cheers Wallace

[hans_o_man]

Hi Wallace,
more than ten years ago I findished my very first PC-programming projects: Designing jerk-free valve lift curves by a quite simple mathematic model,(Bensinger/Kurz of Daimler Benz) and a different program, to convert those curves into the shape of the a camlobe, depending on the head-geometry, or flat tappet cams. I used "Borland Turbo Pascal 6.0" on MS-DOS 6.22... Outputfile is a textfile which my 21 year old CNC-mill understands, so I can mill single camlobes, which I assemble to camshafts, or, made of aluminium, as a grinding gauge for a professional cam grinder. I designed several different cams for XT500/600, a 125ccm Minarelli-2valve single, and for different very old brit bikes in race use. There may be more modern calculating processes for harmonic or jerk-free valve lifts, but my one works good for me.. If no one can help you, I can try to make my programs' outputfiles fit to your CNC. But you should first have the exact actual curves.

Cheers,
Hans

>
> We are limited here in NZ to existing CAM profiles from a few cam grinders. No CNC chaps here for Honda's !!!!
>
> Does someone have the maths skills to calculate the valve movement transferred from the CAM through the rockers ? It's not rocket science but I'm getting too old for this now.  
>
> I would like to design my own cams cause I have a spare CNC lathe that I can convert to a CAM grinder.  
>
> Cheers Wallace
>

[Michael Moore-3]

Hans sent me a couple of his lobe output files a few months back and it
wasn't too hard to convert the g-code text files into point files that I
imported into Rhino and then snapped a smooth curve through the
points.  I think I fiddled with the g-code files in Excel to eliminate the
data that I didn't need for the point cloud.

Hans' file was probably just fine, but I felt it would be easier to work
direct with a curve in Visual Mill to generate code with the post-
processor for my mill's control.  It also let me change the part zero
locations.

Once  a drawing existed it also gives the possiblity of scaling the lobe
up/down as needed.

Hans, you should post the link to your website with the photos of the XT
and other parts.  I think people would enjoy looking at them.  I certainly
found them both interesting and informative.

cheers,
Michael

[Ava Pxia]

Although I see nothing wrong with what you use that does your job, any modern spreadsheet program can be arranged to have the output you want.
If you send me a copy of one of your output files I can maybe help you create a report file for excel that will have the right output.
It is most likely comma delimited csv or something similar
1,2,3,45
2,3,4,65
4,3,2,43

The first CNC I worked with back in 81 had tape reading, you typed the codes into a special typewriter and fed the tape, an other had cards.  Then disks and stuff were invented :)  



--- In mc-engine@..., "hans_o_man" <der_hiha@...> wrote:
>
> Hi Wallace,
> I used "Borland Turbo Pascal 6.0" on MS-DOS 6.22... Outputfile
> is a textfile which my 21 year old CNC-mill understands, so I can
> mill single camlobes, which I assemble to camshafts, or, made of >
> Cheers,
> Hans

[Michael Moore-3]

I just put the patent by Bensinger, a patent they referenced, and one
referenced in the second patent on my website in:

http://www.eurospares.com/graphics/engine/

They are the three pdf files that start "CamUS" followed by the patent
number.

cheers,
Michael

[Michael Moore-3]

I found two more patents by Deschler and Vogel and added those with
the others.

cheers,
Michael

[Jim Schneider-4]

I have an excel file that I would like to enable to display
graphs/shapes for data input.  Can you help me with set up?
 
Swiss
 
-----Original Message-----
From: mc-engine@... [mailto:mc-engine@...] On
Behalf Of zerogara
 Subject: Re: CAM Calculations for single overhead cam.


Although I see nothing wrong with what you use that does your job, any
modern spreadsheet program can be arranged to have the output you want.
If you send me a copy of one of your output files I can maybe help you
create a report file for excel that will have the right output.
It is most likely comma delimited csv or something similar
1,2,3,45
2,3,4,65
4,3,2,43

The first CNC I worked with back in 81 had tape reading, you typed the
codes into a special typewriter and fed the tape, an other had cards.
Then disks and stuff were invented :)

--- In mc-engine@yahoogrou <mailto:mc-engine%40yahoogroups.com> ps.com,
"hans_o_man" <der_hiha@...> wrote:
>
> Hi Wallace,
> I used "Borland Turbo Pascal 6.0" on MS-DOS 6.22... Outputfile
> is a textfile which my 21 year old CNC-mill understands, so I can
> mill single camlobes, which I assemble to camshafts, or, made of >
> Cheers,
> Hans