I’ve been building and modifying a motorcycle (the metaltechs have been hugely helpful already), and by solving one problem I’ve created a new one
I needed to make some space for a frame bar to tidy up the lines, and the massive airbox was in the way.
so I cut it.
The problem is I now need to seal it, with the cut out piece con-caved inward to be air tight. I’ve tried a quick 3D scan/model to start with, but I’m not sure this is will be adequate.
Basically, I was thinking of creating an insert that can be glued/rivited, or even shape some fibreglass. There are examples of 3D printed full airboxes, although thats a fair bit.
Does anyone have any suggestions to sealing this now large gap? Its about 20cm long.
Fibreglass screams at me as the right choice there.
Just to be the devil’s advocate here, have you considered how changing the shape and volume of the airbox could affect the engine air intake and, therefore, the performance?
I don’t know in your specific case, but for high-performance sports bikes, the volume and internal shape are designed to very strict boundaries, with very careful consideration to internal fluid dynamics, turbulences and resonances.
As I said, this is probably not the case, but worth thinking about.
Back on how to “seal” the gap, a thin 3d print with fibreglass lamination is probably what I would choose if I were in your shoes. Or maybe a piece af ABS and a plastic welding machine? (expensive unless you can borrow one from someone).
@stefanoromano, yeah I’m in agreement - I’ve ordered a sheet of 4mm Polypropylene - I dont know enough about plastics to know which is the best - but I think I just want to prototype some.
Regarding the flow - yeah, there will be a slight volume decrease, but the important bit is leaving the inner tubes alone as they are what gives the motor torque. A lot of after market replacements dont have them, and the peak HP increases (as usual with shorter stacks) but torque suffers. This is not a race bike, so want to keep it as is as much as possible.
I think we’re coming at the problem from 2 different angles. I was thinking you dont want the fibreglass to stick to it, ultimately it stands on its own once moulded?
The other options I wanted to see if I can simply create an insert out of the plastic that can be glued/platic welded in.
