Is it considered rude to join two different organisations?

I belong to one Federation and love my club, however, it only meets once a week and other clubs in the same federation aren't too close by, meaning it would be a bit of a hassle to train more regularly. Also, it only seems to have one course and grading all year in Scotland. After some research, it appears there is another Federation's club near me that practises 3 times a week and offers courses more regularly. This looks like it would be more convienient.

I wouldn't want to leave my club or offend anyone and was wondering if any of the more learned or experienced members could offer some advice on my predicament please? As I say, I really enjoy my club and have the utmost respect for my Sensei and I'm sure he would be most helpful. I just simply wouldn't want to rub anyone up the wrong way.

The best thing to do is to speak with your Sensei about it, and tell him how you feel and what you are thinking. Once you've done that, go to the other club and do the same with the other Sensei. That way, there are no misunderstandings and you won't get caught up the politics of the situation.

Ditto what Nafis said above. Open communication and open intentions are the best path to take.

Why is it necessary to tell your sensei that you've decided
to join another dojo? I understand you don't want to hurt anybody's feelings but their egos should be at a stage where being hurt in that way in moot. Go where you want to go.

OSU

At the risk of imposing my own values, if someone is your sensei I believe you owe him/her some amount of resect, which requires some amount of openness, honesty, and communication of intention, whether implied or specified. I think it is common courtesy to let someone in your life know whether you're coming or going. I'm a bit old fashioned and idealistic, but I do believe in loyalty.

also training in another club will have a direct impact on the direction your aikido develops. As one charged with the development of that Aikido the sensei has a right to know imo. If he decides to say you can't train at both and you decide that is unreasonable, no reason you can't leave.

It's always better to be open than hide stuff.

Definitely speak with your sensei. If, after some classes at the other dojo you find out the style, people, sensei or whatever, isn't what you thought it would be or doesn't feel right, it is much easier to return fulltime to your first dojo. Without any funny feelings or glances.
Every dojo has its own vibe and it has to agree with you otherwise the study of aikido will become much less enjoyable

Does the other club "fit" you? Will it help your budo? Does the other club train at a level of intensity that suits you?

I believe you should be up front about it, in case either instructor has a problem with it. Remember that people can take offense, even if you didn't intend to give it, so the value system of others is involved. But the decision is yours, so you must make it with the best intentions you can, and be prepared to accept the negatives, if any. I think a lot will depend on how complimentary the two "styles", if you will, are to one another. I think it would be more difficult to differentiate two very different methodologies, as you are not supposed to be thinking about it as you practice.

And this is very important: Do not let the words "This is how we do it up the street..." come from your lips unless you are first invited to do so by your instructor. To do otherwise would be very bad manners.

And don't forget that you'll be training more with the new club so your aikido will more than likely take on whatever "shape" the new sensei teaches. You will also be grading under that sensei and progressing in rank faster than the students at your current dojo. If all this happens you have, in fact, changed who your main sensei is and have relegated your first sensei to "the place you train once a week for more practice".

You could try the new place, but if you like it you should formally switch your main affiliation. If you take rank under the new sensei you are his student.

Just my opinion,

Bronson