Simple bench

For this third consegna i tried to do a simple bench from similar parts. The idea was that I create wooden profiles and connect them with steel pole.

1. I created profile with extrusion - all asigned parameters are Type parameters, except for height parameter, which is an instance parameter, so I am able to generate different profiles:

2. Also the thickness of the profile was asigned as a Type parameter:

3. I created now holes inside my profile - at both starts of the profile and in the middle, so I am able to rotate and connect the profiles in different positions. And with all that, I created different Types of my profile:

4. Lastly I asigned my profile a material - wood_oak. This parameter is shared paramater:

5. I also created a pole family, which will connect my profiles:

6. With all that, I imported all the things into main family, turning the profiles as i wanted them to be and constructing a model of the bench:

7. But when it comes to creating schedule for my model, I didn't know how to do it... So i decided, I will create another bench, which would be more simple, by using just the pole and one of my profiles, which will be rotaded differently, to give the bench the stability. To create that, i used array tool:

8. And now, with setting my familys to shared, i was able to create this simple schedule:

But somehow, I cannot change the length of my bench. The length is set as Type parameter, so I cannot put more benches into project and change each one of them. But I also cannot change the parameter to instance, because it is used in a formula for another parameter. Any soultions?