Creating tabs for easy assembling on cnc-routed parts

[RianDeRous]

I'm working on a new project. This is a Belgian shunt locomotive in 7mm scale:

All different parts will be routed out of sheets of 2mm thick PVC. For easy assembly I add 4*2 mm tabs that will fit into a rectangular hole in the other part. Without this, assembly is a real nightmare because aligning different parts is very difficult or almost impossible. So far, in this project, I only added these tabs for the front panel of the cabin. 

My problem: i really hate it to draw them. It's very time consuming. It takes quiet a few steps to draw a tab and a matching hole:

1. Draw the tab
   1. I use tabs of 4 to 5 mm wide and 2mm thick (just the thickness of the material)
   2. Sometimes, tabs of only half material thickness are required for aesthetic reasons:
      1. tabs of only 1mm and/or holes only to half depth.
2. The corner should have a dogbone fillet so i can route it with a 1mm router bit. Otherwise it won't fit very well. 
3. Draw the corresponding square hole, just 1/10 of a mm larger in each direction for a good fit
4. Add dogbone fillets to the corresponding rectangular as well..
5. repeat this process over and over again until the whole thing is just like a puzzle that's easy to assemble
   
   
   How can fusion help me to do this faster? 

[kate.raskauskas]

@RianDeRous,

Are all the tabs/holes going to be the same size, or the same size with two different thicknesses? If so, I would try making two bodies - one for the tab and one that's in the shape of the hole. Copy and paste those bodies where you want the tabs/holes to be, then use the Combine command to add the tab and cut the hole into your parts. Do you think that might work for you?

[davebYYPCU]

You can the take the process @kate.raskauskas suggested a little further with proper planning, by using, Linear or Rectangular Patterns, and the Mirror command, where appropriate.

I would avoid drawing them into sketches, 

Might help...

[RianDeRous]

To get something that's really like a puzzle, 4 different tabs (and matching holes) are required. 

1. 4*2*2mm (like in the picture above), full tab
2. 4*2*1mm (tab half material thickness)
3. 4*1*2mm (matching hole half material thickness depth)
4. 4*1*1mm (combination of 3 and 2)

The first one and the second type are most important to simplify the assembly process. Where (1) is used, i also can use 2, but not the other way around. The left and right cabin plate needs a tab of type 2, because otherwise, the tab would be visible from the side. Type three and four are not important. The parts that need a tab of type 3 and 4 are not the most important parts (normally i don't use them, those parts are most of the time parts that can be glued on when other parts are already assembled using the tabs that guarantee that walls are perpendicular and things like that.

(example: the plate at the very front of the shunter can be glued on the chassis when the chassis is glued onto the base plate, but aligning the chassis to that base plate is not easy when there are no tabs and matching holes....) 

I will try your suggestion! thanks!