Filament Support For Dual Extruders

Don’t know if anyone else has this problem with their dual extruder but when one of my head’s filament is idle for a long time the point where the filament enters the extruder becomes weak from bending back and forth when the X axis moves and it eventfully breaks. Maybe the issue is because of where my spools are on top of the enclosure my TAZ5 is in. In any case I fixed the problem by adding a simple support bracket to my dual head. I no longer have broken idle filament.

Before the bracket

With the 3D printed bracket installed (yes it clears the top of the TAZ frame). The OEM screw was replaced with a M3x30 screw and the bracket is held on with a wing nut. The bracket does not have to be removed to change filament. The holes in the bracket have to be large enough so the guide tube can move freely at all Z axis heights and X axis positions.

Very nice! I had the same problem, and did something similar:

https://forum.lulzbot.com/t/dual-extruder-v2-filament-guide-bracket/2861/1

One thing I like better about yours is that you left more clearance so that you don’t have to remove the bracket to change the filaments. That’s especially important because more pressure and flexing of the head during filament changes means an increased likelihood of having to re-level everything.

My design actually holds the ends of the filament guide tubes; they are an interference fit.

I also can’t tell from the pictures if there is a radius on the inside corner of the bracket. It kinda looks like there isn’t. Having a radius there will greatly increase the strength of that corner.

The is no radius on the inside of the bracket. The top holes are larger than they appear in the picture so the guides easily side within the bracket so there is no up and down movement of the bracket. I didn’t design the bracket. It was a right angle bracket that I found on Thingiverse and messed with the dimensions so it worked.