Running Candle for Different CNC Routers

Written By Graham Bland. You can find me on the Facebook group SainSmart Genmitsu CNC Users Group. All comments, suggestions, and corrections are welcome.

I have 6 different routers! There are also different spindle motors (Brushless and GSM 20K) which I sometimes change around between them.

Each router and motor combination has different settings in Candle, including spindle speeds, bed size, and Z-probe thickness. It would be nice if Candle had a machine database, but it doesn’t, so I had to change the settings frequently.

I am using Candle version 1.1.7, the latest full release.

All the Candle settings are contained in a single file, settings.ini, located in the main Candle directory. I considered creating a startup file that would create a symbolic link to the settings file, but that would only allow me to run a single instance of Candle. Sometimes I want to run more than one instance to control multiple routers simultaneously.

So I came up with the following simple solution.

As Candle is a small program (72.7MB, only 202 5¼” floppies and 4 times the size of the hard disk on my first IBM PC!) and does not create or rely on any registry settings or use directories outside the single installation directory, multiple instances can be installed. Just create a directory, unpack the files, and run the .exe. Installing multiple copies is easy.

You can change the locations and directory names as you like.

Create a directory on your PC; I put programs like this in my “C:\Other Program Files” directory, so I am using “C:\Other Program Files\Candle”.

Create a subdirectory for each router, using a naming convention of Candle-.

So I ended up with:

“C:\Other Program Files\Candle\Candle-Default”
“C:\Other Program Files\Candle\Candle-6050”
“C:\Other Program Files\Candle\Candle-4040”
“C:\Other Program Files\Candle\Candle-4040Brushless”
“C:\Other Program Files\Candle\Candle-3020”
…….

Install Candle into the Candle-Default directory by extracting the contents of the Candle directory in the .zip file into that directory.

Start Candle by running Candle-Default\candle.exe, and change any settings to your preference.

Ignore machine-specific settings; leave the machine information alone. Change the probe and safe position commands to the generic ones you want to use, ignoring things like Z movements and probe base thickness. Save the settings and exit Candle.

Now copy all files and directories from the Candle-Default directory to the other Candle-... directories.

For each Candle-... directory (e.g., “C:\Other Program Files\Candle\Candle-6050”), rename the Candle.exe file. This name will be shown in the top left of the Candle window and identifies the instance you are using.

For example, rename C:\Other Program Files\Candle\Candle.exe to C:\Other Program Files\Candle\Candle-6050.exe.

Create a shortcut to the .exe file and add it to your start menu, renaming the shortcut if you wish!

Start the specific instance and change any settings for that specific router. These settings will be saved under that instance and will not affect others. This includes any settings, colors, and fonts; they will apply only to that instance.

How many instances you can run depends on your computer's power and the available USB ports (including any hubs). I have no problem running three instances simultaneously.

I am fairly certain that this approach will not work with UGS or Openbuilds, as they both use other directories outside the main installation directory. Both UGS and Openbuilds will only run a single instance, but I may be wrong; I just don’t have the time to investigate fully.

Be careful to connect the correct instance to the correct router, but that is fairly simple if you are methodical.

Even if you do not want to control more than one router at the same time, this technique is still useful for maintaining separate settings for different routers.