What considerations apply to material selection for cartridge mounting bolts?

@mylogic 

My Garrard 301 was given to me by my Dad, as it happens the last time I saw him.

It included the SME plinth, which I have very extensively modified inside (you probably cannot see any differences from the outside).  I've done a fair bit of work on the Garrard, replacing the main bearing and most of the service parts like springs and idler.  

I've not done anything to the SME except mount and dismount it and resolder a connector.  Maybe that's where I came across nylon bolts.  Clearly SME did everthing possible to get the effective mass down.

I could buy a complete Audio Technica VM540ML cartridge cheaper than a Jico SAS/B stylus for the Shure.  With the Audio Technica, the Garrard / SME sounds broadly as good as CDs to me.

@lewm suggested vinyl could be much better, and I did buy the Jico but never got the chance to fit it.  Then Holbo came up with their direct sales model and I could not resist the combination of air platter bearing, air tone arm bearing, tangential tracking and ridiculously low price!

My Shure was lying around so in went the Jico and eventually it got bolted to the Holbo.  I did have some washers, and fitted the bolts upside down with washers top and bottom.  The Jico stylus picks up a lot less surface noise (groove wear?) with its micro-line diamond compared with the elliptical Shure stylus.  I still have it, and it would be a very easy swap.

I have bought an expensive cable for the SME arm - no joins in between the cartridge and the pre-amplifier, and balanced.  When I get the Holbo singing, I'll be pulling wires through the SME.

For what it is worth, I removed most of the hardboard bottom of the SME plinth, reinforced the corners with Aussie ironbark gussets, and filled the interior with three thick MDF slabs, cut out where necessary. The slabs are separated with constrained layer damping, and the motor board sits on the top slab.  The slabs in turn sit on three IsoAcoustics OREA Bordeaux isolators.  The outer plinth is air gapped from this inner structure.  I have designed the changes so the motor-board can be sprung from the outer plinth, but I have yet to feel the need to do this.

@lewm 

I cannot discuss T without risking a cardiac death

Nowt wrong with that provided it is T's and soon!

I’d like to find nylon screws and nuts, but the ones I’ve seen on Amazon and eBay have standard hex nuts. It’d be nice if there was a set out there with circular nuts. It’d make it easier with some carts.

Soundsmith sells some. https://www.sound-smith.com/accessories/ez-mount-cartridge-screws

@audphile1 

"I really like the Riverstone Audio gauge. You should check it out."

I've seen good reports about it previously elsewhere I'm sure but if I was going spring for "digital" I'd probably go with the Rega Atlas and get it right the first time.

@lewm 

"In my several decades of experience with it, the SFG was imprecise and results were often not repeatable. Plus it could damage a cantilever if one were not careful. These days it makes no sense not to use a digital scale, just making sure that the one you choose has its weigh pan in the plane of the LP surface."

Well maybe you're rather fumble fingered and just don't have the touch but I've found the SFGII to be exactly how I described it upthread. If it ain't broke...

If any of you lived nearby and had the privilege of hearing my systems playback I seriously doubt, if you evaluated it honestly and unbiased that you could be critical of the sonics in any way! 

It should be obvious which coast I live on if you consider reaching out.