Just realised I never actually posted an update on our rebuilt/reinforced flush lever here.
I wasn’t able to weld the aluminium, it was going to be too difficult. So I went with JB Weld in the end.
The square aluminium tube is 20mm OD and approx 1mm thick.
The round aluminium tube is 20mm OD and also approx 1mm thick.
I modeled them in FreeCAD, then designed a cutting template for the square tube:
I 3D printed it, drilled lots of holes, then filed it smooth until I got a clean fit.
To actually join the two pieces together and increase the amount of surface area for the JB Weld to attach to, I designed this insert piece for the square tube:
It supports having two long bolts which run through holes into the round tube:
The round tube end cap holds two captive nuts for the bolts to screw into so I can get a tight fit:
So we basically now have this part fully assembled:
The next step is covering the square printed piece with JB Weld and sliding it into the square tubing, and pouring some more down the inside to try to get good coverage between the tube walls and the two bolts (we’re aiming for metal to metal contact). The rectangular slots in the printed piece allow the JB Weld to make contact with the metal tube better.
Then I apply some more JB Weld to the outside wherever the two tubes make contact:
The final two printed parts are the round endcap (which also gets filled/covered in JB Weld before being installed), and the square endcap (which is a tight pressure fit and can be removed if needed):
After letting it dry I sanded the whole thing smooth and drilled the hole for the lever bolt (using the broken wooden handle for reference):
I primed it, but this revealed some defects I wasn’t happy with, so I sanded it and repaired them before priming again:
I don’t think you’d ever know that the endcap is 3D printed!
Two coats of Rustoleum Apple Red paint and we’re done!
Since this was finished, we’ve run multiple events without any issues. The paint hasn’t even cracked at the join, so it’s definitely not flexing. A lot of kids (and even a few adults) have been VERY rough with the handle (despite our instructions to “pull the handle gently”) and it’s held up fine so far.
If this was still made of wood it would most likely have broken again by now. Or worse, if it was 3D printed we’d probably be replacing it 2-3 times each event :lol:
We’ve talked about making an identical handle to keep in the spare parts box but so far it hasn’t seemed too urgent. I should probably do it anyway just in case. You never know when someone’s going to try recreating Frozen Empire :lol:
