How interchangeable are brick types?

[Khasen]

I am collecting parts to build a very big MOC, and it will be expensive to source all of them.  The plans call for a number of 1 x 2 technic bricks, part number 3004.  Since these parts will be in the internal structure and not visible in the completed model, I want to use some of my spare parts.  I have a bunch of 1 x 2 technic bricks with hole, part number 3700.  The pegs on top of the 3004 bricks are solid, but the pegs on top of the 3700 bricks have a hole in the middle (in addition to the hole through the side of the brick.)  Are the 3700 brick pegs structurally strong enough to be used in place of the 3004 bricks?  The pegs seem to hold as tight as the ones on the 3004 bricks when I test them myself, but over time I don't know.  These bricks are part of the structure inside the MOC, which is why I'm asking if anyone knows or has any experience or ideas on substituting bricks like this, and are the 3700 bricks are okay to use. 

Thank you in advance.

[Toastie]

Hi @Khasen,

and welcome to EB!

Others may know much better, but have never ever had any issue with the hole-pegs. I believe some of the technic beams I used for my "structures" here are dating all the way back to 1996 (Control Center II / set 8485) and they don't have any issue, nor are they structurally weaker than solid peg beams.

But as said, the technic gurus here know better.

Best
Thorsten

[Khasen]

Thanks for the information, and the benefit of your experience. I will go ahead and use them in my MOC.

[MAB]

I frequently buy technic bricks as cheap replacements for standard bricks. Even if you are using them on an exterior facing wall, ones like this

can be a very cheap replacement if you cannot see the other side. For internal structure (in any colour) they can also be connected with technic beams to span a structure to make it strong but light.

[62Bricks]

If anything, I would assume the Technic bricks can withstand more stress from weight over time than regular 1x2 bricks, as the long sides are connected inside by the walls of the pin hole. That makes them less flexible, however, which, may make them more susceptible to crack over time from the clutch stress from studs.

[Johnny1360]

7 hours ago, MAB said:

They can also be connected with technic beams to span a structure to make it strong but light.

Very good point and crucial for making large shell like structures more robust and appear more substantial, definitely saves on weight and overall number of pieces to make a solid structure.

[Khasen]

Good idea using tecnic beams to reinforce a structure, when it is on the inside and not visible.  I have seen MOCs that fell apart easily, and using such bricks would be a big help.  Thanks for that tip!