Saving a Lady

Tappet cover wing nut, early-50s Bullet

Being poor and mean, I prefer to scavenge or else home-brew wherever possible so you can readily imagine my recoiling in miserly horror at the thought of shelling out five quid for something which cost pence (or rupees) to make.

Such a thing is the little gewgaw which holds the tappet cover in place on a Royal Enfield Bullet. It looks cool, mirrors the original Redditch set-up and is actually rather useful if you want access in a hurry or at times of stress. Of course if you're found wanting for lack of spanners, being able to remove the cover will be of little use – but that's to over-think the problem.

Chennai Bullets ship with a domed nut which is not unattractive but doesn't have quite the charm of the original wing nut or the repop version available from the usual sources.

Chennai Bullets ship with a domed nut

Aftermarket repop wing nut

The aftermarket nut is a casting, drilled and tapped through the fat part (much like, I imagine, Kim Kardashian). I don't have a furnace but I do have a lathe though I don't have a ball turning attachment (that's something else I need to make). What all this equates to is I can't cast my own wing nut but I can turn something approximating it in use if not in aesthetics but which won't have the attractive ball-end on the wing.

Clear as mud?

Scrabbling about the workshop for some scrap I lit upon a length of 13mm hex bar. I have a number of these waiting for future projects but for this particular one, the limelight had arrived. Once chucked, I cut off the threaded end, faced it and put on a slight chamfer.

Scrap 13mm hex bar

First steps…

The stud for the cover has an M8 thread (at least, for those Bullets made after 1999). I selected a 6mm drill as a pilot and drilled a suitable hole. Next I used a 6.9 tapping drill for tapping M8. Then I tapped the hole taking care not to snap the tap (I wanted a blind hole). That done, I used a 10mm drill bit to put a little chamfer on the thread.

Drilling the nut…

…and tapping it M8

Setting aside the body of the wing nut I rummaged up a bit of 8mm steel rod, measured a length I deemed suitable to make the 'wing' and set to on the lathe, turning it to a diameter just below 6mm and then threading it M6. I left the other end slightly larger in lieu of a ball.

Turning the 'wing'

Threading the wing M6

Back to the body, I used a centre drill bit on my pillar drill to make a pilot hole, a 5.2mm tapping drill to take it to the required diameter and an M6 tap. I cut off the body at a suitable length put it back in the lathe to face and chamfer it, put a drop of thread locker on the wing, screwed it into the nut and the job was done.

With the thread cut…

…it's time to part off the wing
(I don't like parting off in the lathe)

The finished wing nut in situ

It isn't as pretty as the original but it does have an old-world charm that I think is rather appealing plus I saved a satisfying £5. Now I just have to figure the best way to grind the fins off the cover itself for a ’50s-like appearance.

What's that? Oh, cockney rhyming slang for a 'fiver'. Lady Godiva…