So GR-55 work only like a interface... you cannot use the internal sound.. right?

You can use the internal sounds on the BASS mode side but there aren't as many patch options as the Guitar side. The Guitar side has patch options like piano, saxophone, flute, harp, trumpet section, etc. Many of the really good patch effects are not available on the Bass side, but as an interface you can get as many instrument effects as you want. If you download the GR-55 manual and go to the appendix, you will see the patch lists for both the Guitar side and BASS side. https://static.roland.com/assets/media/pdf/GR-55_OM.pdf

By definition, Bass has less Patches and fewer/different types of modeling instruments, but I cannot entirely agree that its possibilities are significantly smaller. The number and type of PCM tones from which you build the Bass patch are the same as in the Guitar version. There is nothing stopping you from playing the Guitar Patch on Bass (without modeling). The manufacturer only prepared fewer of them for bassists. However, the ability to create synth sounds is similar. In theory. In practice, for example, Synth Fretless on Guitar will never sound as good as the same PCM tones on Bass. Other sounds will play better on Guitar. At past I used to use two GR55s. One for each side.

The scale is a real problem. I wouldn't demonize her though. There are many other elements that make it difficult to properly set up Stick with GR. One extra is no problem. Sometimes it's worth a bit of effort to be able to use full guitar modeling.

I understand what you are saying. I'll give it a try.
The Stick scale calibration works properly in BASS mode.

It never occurred to me to try importing saved Guitar patches
into BASS mode. It should work as you have described.
My Railboard GK pickup is on the Melody side,
so BASS patches don't interest me.

I've downloaded the GR-55 PCM tone list.
910 individual tone models to choose from.
I'm hoping that these are all available
in both Guitar and BASS mode.

so, if a buy GR 55, the correct setup is to set bass mode and that give the change to use the guitar patchs. Right?

In order to calibrate the Stick scale length, you need to be in BASS mode. Guitar mode is limited in scale length, so the Stick will not track accurately in this mode.

As for the guitar patches, I haven't tested that yet. What the other poster was implying, was that you should be able to create your own patches with the internal options of the GR-55 whether in BASS mode or Guitar mode. I haven't tried this yet either.

I'm busy at the moment building a custom torsion box to use as a stable platform for my OneFinity CNC wood carving machine. I should be able to make my own Sticks with this machine. https://www.onefinitycnc.com/

WOW!! custom sticks!!!

I will only be making a few Sticks for my own personal use.
My main focus is on other products such as 3D CNC art.
https://www.google.com/search?q=3d+cnc+art

I've also designed a briefcase that turns into a stand
for the Chinese cobbler sewing machines.
Millions of these machines were made without a quality stand
or storage system, so I've decided to provide a solution.
https://www.google.com/search?q=chinese ... ng+machine