Wednesday, 15 July 2020

Gland's too small!

When I designed and machined the housing for the 4th axis, I hadn't chosen a cable conduit / gland system for the umbilical. Given that uncertainty, The Stupid Fat Bloke made an executive decision and simply machined a larger bore than would likely be needed. It's perhaps easier to fill a larger hole than have to open out a smaller one, particularly when we are talking about something most likely in the region of 25mm or so.

Naturally, when I ordered the cheapo conduit kit from CPC, it turned out to require a mere 20mm hole. If anything, that conduit's still rather oversized given the minimal cable content. However you look at it, my gland is too small to fill the hole on offer, fnnaaarrr. Sausage in an alleyway etc.

Obviously the only solution is to make up some sort of bushing assembly to fill the gap(s). I need something to stop the whole gland body disappearing into the front of the assembly as well as something out back to tighten the nut against. In general terms these will be "top hat bush" type compts, with dimensions coming from the gland body (M20 thread) and the premachined hole in the assembly (27.5mm for some reason only known to The Stupid Fat Bloke).

It's hardly rocket science. Luckily I have some 32mm mystery loominum stock on the shelf, so there's your starting point - and your outside diameter.

A bit of PencilCAD:

....and off we go:

That's the main bush. Now for the front washer: 

Seems to fit.

It's pretty neat. Not a bad recovery.

Seem to have done a reasonable job and avoided any obvious fuckup:

Hungry dog!

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