Magic Probe Thickness Gauge - Input Needed

**lsnyman** · Jul-24-2012, 11:34am

Members here have been great in the past offerring advice in the development of the MAG-ic Probe. I am producing a universal tip and need some input. Right now the probe is available with Flat and Rounded tips as seen below #1 and #2 to accomodate Mandolins and violin makers.
There is a lot to be said for a flat surface on the probe as it gives a little positive "feel" when measuring.
I am proposing to use a tip that has a very small flat surface and be small enough to fit into most recurves to satisfy everyone. If the user has a tighter recurve or specifically wants a more rounded profile, the edges of the tip can easily be shaped with a sanding block as shown in the diagram by the black dotted lines.
I feel this would give the best of both worlds and simplify production a whole lot. LMI and Stewmac would also have an easier task of inventory etc.

Any comments?
Thanks

Liam

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**Mike Black** · Jul-24-2012, 11:43am

Liam,

I think that new probe would be great. I agree that a small flat surface would give that "positive feel" that you mentioned. I was actually thinking about asking you how it would effect my roundtip probe if I did flatten a small surface area.

**lsnyman** · Jul-24-2012, 1:10pm

Hi Mike
Thanks for the reply. Flattening the tip will cause calibration issues. There is an auto calibration on startup but I dont think it will compensate for as much as you would need to remove to achieve a flat surface.
What is the typical recurve radius that you use?
Appreciate the info.
Regards
Liam

**Dale Ludewig** · Jul-24-2012, 2:31pm

Liam,
Is it calibrating to the middle of the probe tip? If it is, would it be possible to have a series of tips, all the same length with different shaped bottoms, that could screw in? Kind of like a pressure washer has different tips. Then a person could buy the probe and choose the appropriate tip for the job at hand. I don't know what the probe tip material is, but neoprene screws are useful here in my shop. By the way, I show people (even non-luthier types) how cool the probe is often. Perhaps too often!

**dunwell** · Jul-24-2012, 5:25pm

Originally Posted by lsnyman

I feel this would give the best of both worlds and simplify production a whole lot. LMI and Stewmac would also have an easier task of inventory etc.

Any comments?
Thanks

Liam

Liam, how critical is it to have the tip integral to the rest of the probe tube? I'm assuming that there is some magnetic component to it so maybe each probe has to be calibrated individually, dunno. I'm wondering if you can make a single probe tube/core onto which individual tips, maybe made of UHMW plastic, could be attached. Maybe with a twist lock type connect. That way you could ship it with multiple tips at a relatively low cost or sell the tips separate as folks needed again at relatively low cost. Just a thought. Maybe this doesn't work with the calibration or maybe include a way to calibrate with the tip pressed to the magnet??? Just WAGing here.

That aside, I like the idea of the RNFP (round nose flat point) type tip. Can I get that in .45 caliber?

Alan D.

**lsnyman** · Jul-24-2012, 6:52pm

Thanks Alan and Dale
Yes, great idea that I wish was possible. There is a sensor in the tip and the inside measurements are critical to 1000th inch. It may be possible someday but not with current sensors. I think the one tip is a first step toward this and then do a changable tip for the smaller balls.

**Marty Jacobson** · Jul-24-2012, 7:06pm

Liam, looks like a great product. I was not aware of its existence, looks much more useful to me than a Hacklinger gauge. Where are they sold? I didn't see them in the Stew-Mac catalog, at least not under the MAG-ic Probe name... Clever use of Hall sensors (I presume).

**lsnyman** · Jul-24-2012, 9:50pm

Hi Martin
Stewmac have them but not yet in the catalog. LMI has them on the website. Both unfortunately only have the flat tip. You can also buy at my website.
Thanks
Liam

**Mike Black** · Jul-25-2012, 9:21am

Originally Posted by lsnyman

Hi Mike,
What is the typical recurve radius that you use?
Appreciate the info.
Regards
Liam

Liam,
I'm not sure what the recurve radius is. Here is a picture of a couple different recurves that I use. Hopefully that will help.

**lsnyman** · Jul-25-2012, 9:36am

Hi Mike
Thank you for that. I overlaid the tip onto your pic and it looks like it would work great. As I said the user can always round the edge slightly if in doubt.