Concentricity gauge - made in my home workshop. 

Thank you - I find great satisfaction in using stuff I've made from scratch myself.

Thanks Damien - Only happy if I've got a new project bubbling round my head. :)

Thank you Jamie - I will eventually get around to making another small batch of these.

that's what I thought it was / is !

Thank you David - They come in all shapes and sizes and not too expensive.

We use them for all sorts of things from holding job sheets to boards, right through to temporary mounting of gauges on machines.

I think they open up a whole new world of design. What about using opposing magnets as recoil springs/buffers in semi-auto .22's or in place of springs in trigger systems or magazine catches.

Thank you Glen. I looked at several different bearings and eventually settled on Zen bearings, good quality manufactured in Germany. I tested the gauge with parallel pin gauges and find there's no detectable indicated runout. I also tried the more traditional hardened balls to eliminate this perceived problem but the low friction of the bearings make it much "nicer" to use and no less accurate.

Thank you Neal - Unfortunately I can't be much help. This is all handmade, the individual parts all machined from solid blocks of aluminium, the wooden base was cut from a bread board. The small bearing the cartridge rolls on were from Ebay. There are no plans, every one I make is different and I make it up as I go along.

Thank you Vomact - I certainly will.

Thanks for the interest Robin - Unfortunately I machined it myself out of 50 or 60mm Delrin, then I machined a groove to take a 3mm "O" ring.

Thanks for the interest Dale - I've made 8 or 9 of these gauges, all slightly different - I never draw up plans, just make it up as I go along. Here's another in progress at the moment: imgur.com/7sjqxMx

Unfortunately not Rod... But I will (eventually) :) If I make another batch I'll certainly hold one back for you.. Allan

Tnks alan theyre beautifully crafted

Hi Rod - Sorry, not got round to another batch of these yet. Working on several other projects - I'll post a video of new stuff when they are up and running. Most of my time is taken up making the Targetmaster auto-tricklers.

Thanks for the interest, but no unfortunately not yet, they are on my "to do" list though - I'm working on another couple of projects at the moment and hope to get another video up shortly.

@@Targetmaster1066 Keep up the good work! Love your videos!

Really appreciate the encouragement - I'll try to improve quality and content...Too many projects - too little time. :)

Thank you Rod. I made just five of these - all sold before I'd finished them. I'm doing a dozen different things at the moment but if I get chance I'll do another small batch.

Tnks for getting back to me I would be happy to buy one looks like really good quality. Do let me know pls. Thank you:)