Roof Cane Supports

One of the biggest problems with our greenhouse was supporting the cucumber and tomato plants when they became top-heavy. Bamboo canes in the pots worked well but sometimes the sheer weight of fruit made the whole thing topple.

A simple roof anchor for the canes was needed. Over the years I tried several ideas with varying degrees of success, but fixing to the greenhouse frame, especially at the meeting of the gables and roof, without damaging or weakening the aluminium extrusion was a problem, as was making something that could be easily (re)positioned or removed for cleaning.

With the arrival of the 3D printer, a little experimentation eventually resulted in this solution. Some simple 3D printed parts attach firmly to the roof and provide anchors to support 12 mm dowels or canes to which vertical canes can be attached.

The end clips and joiner have printed M6 threads for bolts or screws, however, some further experimentation showed that attaching the end clips to the greenhouse frame worked most reliably with finger-tightened printed thumbscrews.

When I created the threaded parts I was still new to Fusion 360 and hadn’t learned about offsetting techniques to ease threads at the design stage, so it was necessary to clean up with taps and dies. When I get time I shall probably “tweak” the designs for a better fit.

My preferred solution…

There are two versions of the intermediate guides. My preferred solution uses an M5 screw and hammerhead nut. The second version uses long M6 cropped head greenhouse bolts and nuts. Both work equally well.

The joiner came later in the “design process” when it eventually dawned on me that there was no way of inserting the dowel through the clips along the entire side of the greenhouse without removing some of the glass first – Doh!

The prototypes (pictured above) were printed using PLA and appear to be standing up to the rigours of temperature and sunshine well. If they fail I will probably reprint them using PETG.

Click to open the Fusion 360 Viewer
Click the image to open the Fusion 360 Viewer

All the parts can be printed as illustrated. The only part that needs support when printing is the end clip because it has a cutaway section to allow a reasonable fit around the aluminium extrusion it attaches to.

 When installing the clips I cut an old piece of bamboo cane to a suitable length to use as a “measuring stick” between the top of the side wall and the clips to quickly align them. Obvious really, but sometimes I overlook the obvious…