Several Months ago I started a thread on Home Model Engine Machinist forum (HMEM) named "Grinding Cams - will this work"
Grinding Cams - Will this Work? - Home Model Engine Machinist
For those of you who are CNC mill equipped and have a tool post grinder and a rotary table, we now have a properly working program that will generate Gcode to produce a cam lobe. All you need to do is make a mount for your toolpost grinder to the mill and you're on your way.
We named the program Gcam and it is free to use. It's is a web-based application so you don't need to install anything. You enter your specs into the program on-line and it creates the Gcode in a file you can download to your machine. We hope it will become more popular than CamCalc especially since GCAM creates a perfectly ground Cam automatically. No clumsy spreadsheets full of numbers and no facets to file off at the end.
It works like this:
You set up your camshaft or cam pair blank in a rotary table horizontally along the X-axis on your mill table and mount a grinding wheel fixed to the back of the machine. The Gcode drives the Y-axis into and away from the grinding wheel and turns the rotary table to control the shape. This gives you a finish ground cam exactly to the specs you choose.
(Optionally you can use a ball nose milling cutter and rough out a cam and file it like with CamCalc and/or finish grind it with GCam in another operation. In any case the Gcode takes care of all of it.)
What we're looking for is some people to try the program. If you already have a CNC mill with a rotary table and you have a toolpost grinder then all you'll need to build is a mount to hold the grinder solid to the mill and you're on your way to perfectly ground cam lobes.
I've created a Yahoo group for the program at
Yahoo! Groups
If the link above doesn't work the group name is Gcam_CNC
The reason for the Yahoo group is that it's easier for me to manage the pictures and users manual changes with direct access as moderator.
If you already have a Yahoo account then please join that group. I've posted a full users guide and a lot of pictures of the setup in the files and pictures section to help you out.
We already have on board Mike Rehmus from Model Engine Builder magazine and Carl Wilson who has written several articles for that magazine on grinding cams.
If all you want to do is have a look at the program and generate some Gcode to look at, then the program is available at the website for the Toronto Society of Model Engineers at TSME.CA
Look in the "Resources" tab on the left side. In there you'll find a link to GCAM.
You should really download the users manual from the Yahoo group since there are a things that need to be explained about the program.
All we want is to get the program out there for comments and to see if it will be useful to you people that are equipped with CNC mills.
I've ground several cams with it and have done some checking at 16x magnification and it appears to generate cams with a nice ground finish but we need to get more people grinding so we can see what other issues the program has. We've already improved it considerably in the last few months thanks to some feedback from users.
We'd appreciate some further testing and comments.
I'd hate to have to duplicate the effort on two forums but if you want, you can comment here as well.
Thanks
Dave Sage
John L. (programmer)
Grinding Cams - Will this Work? - Home Model Engine Machinist
For those of you who are CNC mill equipped and have a tool post grinder and a rotary table, we now have a properly working program that will generate Gcode to produce a cam lobe. All you need to do is make a mount for your toolpost grinder to the mill and you're on your way.
We named the program Gcam and it is free to use. It's is a web-based application so you don't need to install anything. You enter your specs into the program on-line and it creates the Gcode in a file you can download to your machine. We hope it will become more popular than CamCalc especially since GCAM creates a perfectly ground Cam automatically. No clumsy spreadsheets full of numbers and no facets to file off at the end.
It works like this:
You set up your camshaft or cam pair blank in a rotary table horizontally along the X-axis on your mill table and mount a grinding wheel fixed to the back of the machine. The Gcode drives the Y-axis into and away from the grinding wheel and turns the rotary table to control the shape. This gives you a finish ground cam exactly to the specs you choose.
(Optionally you can use a ball nose milling cutter and rough out a cam and file it like with CamCalc and/or finish grind it with GCam in another operation. In any case the Gcode takes care of all of it.)
What we're looking for is some people to try the program. If you already have a CNC mill with a rotary table and you have a toolpost grinder then all you'll need to build is a mount to hold the grinder solid to the mill and you're on your way to perfectly ground cam lobes.
I've created a Yahoo group for the program at
Yahoo! Groups
If the link above doesn't work the group name is Gcam_CNC
The reason for the Yahoo group is that it's easier for me to manage the pictures and users manual changes with direct access as moderator.
If you already have a Yahoo account then please join that group. I've posted a full users guide and a lot of pictures of the setup in the files and pictures section to help you out.
We already have on board Mike Rehmus from Model Engine Builder magazine and Carl Wilson who has written several articles for that magazine on grinding cams.
If all you want to do is have a look at the program and generate some Gcode to look at, then the program is available at the website for the Toronto Society of Model Engineers at TSME.CA
Look in the "Resources" tab on the left side. In there you'll find a link to GCAM.
You should really download the users manual from the Yahoo group since there are a things that need to be explained about the program.
All we want is to get the program out there for comments and to see if it will be useful to you people that are equipped with CNC mills.
I've ground several cams with it and have done some checking at 16x magnification and it appears to generate cams with a nice ground finish but we need to get more people grinding so we can see what other issues the program has. We've already improved it considerably in the last few months thanks to some feedback from users.
We'd appreciate some further testing and comments.
I'd hate to have to duplicate the effort on two forums but if you want, you can comment here as well.
Thanks
Dave Sage
John L. (programmer)