Cantilever Grafting

A DIY option of how to effect a repair of a sheared cantilever using a cactus thorn as a splint.
I picked this method up from a member of a vinyl forum, tried it and it certainly can work.

A cactus thorn is pretty much the ideal splint - small, light, strong and easily formed.

Here's the donor

Form into a spike at both ends and ensure a perfect fit into both sides of the broken cantilever.
I used nail clippers to trim and fine sandpaper to finish, holding the thorn with tweezers.

The below pic was a work in progress, not yet glued in place, just checking the stylus side fitment.

When the thorn is finished and a perfect fit confirmed, glue into the stylus end of the cantilever (I used UHU for this).
Set up the cart in some form of holder such as a small vice, it must be secure.

Apply a dab of glue to the exposed thorn and insert.
Use a pocket scope (or naked eye if you're up to it) to set it square then leave to dry.

In this case I ended up using Super Glue as I only had a very small amount of cantilever stub to play with, I had to move quickly to get Azimuth correct before the glue set.

You do need a fairly steady hand, but generally you don't have much to lose in these circumstances so always worth a shot.

The end result in action

There's a little bit more to this particular grafting application - in this case the diamond/cantilever is applied to a different carrier.

Bit of a long story but the stylus used here is a nice nude 8MR, but I was not happy with the suspension.
The treble had started to deteriorate following some potting exploits - Part of the beauty of keeping recordings of all of my carts.

My mate Bammer sent me a busted G2 stylus body, snapped off towards the base, so I had a go at mating the pair to fit to one of my HO Grado bodies.
So it ended up as a truly Frankengrado combo (Z+/G2/8MR).

How it sounded? - First reaction was Wow!- Really dynamic and alive, retaining the bottom end punch and extension that I was used to.
But, it became clear that the top end had become accentuated and a little too hot for my tastes (sort of AT territory).

I believe the driver for this is a slight mismatch in delivered overall cantilever length.
The stub of the donor carrier is a little longer than the 8MR and also, there's a slight gap between the two.
Upshot is that the cantilever in this case is approx 1/16" too long - I think it is this that is driving the hotter top end.

But - Once again resistive loading came to my aid. Dropping down tamed it nicely.
Perfectly acceptable and for me more than a match for a Grado Gold.

I'm pretty convinced that if you mated the same two halves back together then you won't have lost too much.
The key lesson I learned here though was, for future applications, to make sure the original cantilever length is maintained (pretty obvious really).

Iíve uploaded some sound clips HERE

1: Z+ motor with good 8MR stylus at 47k Ohms
2: Z+ motor with grafted 8MR/G2 stylus at 47k Ohms
3: Z+ motor with grafted 8MR/G2 stylus at 10k Ohms
4: Gold motor with Gold Stylus at 47k Ohms

I popped in the Gold as a bit of a comparator.

Subsequently to making these recordings I dropped the Frankengrado resistive load down to nearer 6k Ohms, but these clips will give a good enough flavour.

So there you go Ė donít just throw away that snapped cantilever - there is a DIY repair option.

Created by Mail To: November 2011