Lathe Tool HEight Gauge

In issue 102 p.42 Ted Wale described his optical height gauge which, to me, seems to be an excellent idea for an oldie.

Has anyone made this for a Myford S7?

And. can anyone tell me where I can can buy the necessary perspex and the small mirror for the job?

Perspex about 1/2"/12mm thick and 3/12" x 2"

The mirror 2" x 1".

Many thanks for any info.

Regards

Richard.

I would've said check your D.I.Y shop for perspex people use it for greenhouses.

But given how thick it is, i doubt they'd sell it so, i do know an engineering plastics firm called Anglia Plastics, they will sell to small users and i once bought a 2" square block of clear acrylic from them for a jig. The website appears to be down but you can find their phone no online.

Rgds,

Michael W

If you can find an old computer laser printer, they have excellent small front-coated mirrors in together with lots of other useful junk.

Alternatively it is about £2.55 for a small front coated mirror here:

www.astromediashop.co.uk/Components.html

Neil

Edited By Neil Wyatt on 07/03/2016 09:56:42

The spirit level type sold by the usual suspects are cheap and effective. It is nice to make your own kit though.

If you have an old hard drive that is scrap you can dismantle it and use the disk as a front coated mirror. The disk is aluminium and cuts easily with a junior hacksaw.

**LINK** for acrylic sheet

Martin

An excellent device. Within reason the thicker the perspex the better but I made mine from 1/4" as that was what I had in in the box intending to replace it once I got something thicker. Not ideal but workable so yet another temporary job becomes more permanent than the proper one.

I used a 1 1/4" square mirror and 1 1/4" cube base block, a little smaller than Teds original. Works fine with my Smart & Brown 1024. On a Myford I'd be tempted to go down to a 1" mirror and 1" cube base. I gave mine extra lines so it can be used standing on cross slide, saddle and bed which can be very helpful if tool resetting is needed with a job in place. The mirror is attached via a nice knurled thumbscrew so it can be easily moved as required. Sometimes its just as easy to use it as a simple line gauge bringing the tool tip up so it almost touches the perspex.

You do need plenty of light, preferably from a source with a reasonable range of adjustment so that things are illuminated from best angles. With simple flat overall lighting the contrast between tool, background and lines can be somewhat lacking. Especially for older eyes like mine. A really good, clean mirror makes visibility far better too. Make a cover so it doesn't get dirty. My mirror was adequate rather than excellent and I didn't make a cover trusting that carefully putting away would suffice when backed up by an annual clean with Isopropyl Alcohol. It doesn't really. Sans cover its amazing how grubby it gets. Slow performance drop off means its easy its easy to forget how good the image is when clean and get in the habit of struggling on with a poor view.

Clive.

Many thanks everyone (particularly Clive)

All the information that I needed - as always you

fellow enthusiasts are wonderful.

••••••••••Regards Richard.

For those without access to the article, this device is basically a piece of thick-ish perspex mounted vertically on a base block. It has lines scribed on each side at centre height. A mirror on on a holder allows you to easily view the lines from above. When both lines and an object are lined up, the object is at centre height.

Neil

Neil, is the purpose of the mirror to save you leaning over the lathe and viewing the tool tip from above ?

Is the mirror holder fixed to a rod as per an inspection mirror ?

Emgee

Edited By Emgee on 08/03/2016 09:42:30

See this thread for pictures of the tool.

**LINK**

Martin

Some so-so pictures of mine from my Optical Height Gauge Album.

.

.

No, it's to save you having to rest your head on the lathe be to look.

Clive, Neil, as usual one picture speaks a thousand words. Thanks for the link Martin.

Emgee

Edited By Emgee on 08/03/2016 11:14:43