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View Full Version : The wheels on the bus go...



irving2008
21-10-2009, 02:09 PM
...round and round... but how fast?

To find out I got myself one of these (http://cgi.ebay.co.uk/New-Digital-Photo-Tachometer-for-Motor-Milling-Machine_W0QQitemZ280412695431) laser photo rev counters off ebay for 95p plus £11.50 postage, £12.49 total (which sounds a lot but when you consider that UPS, Parcelforce, etc, would charge over £20 to ship its 300gram weight, its a bargain).

A quick search before purchase didnt reveal a cheaper UK source (the equivalent Clarkes one is £57) although I did later find an even cheaper ebay source (http://cgi.ebay.co.uk/Digital-Laser-Photo-Tachometer-Non-Contact-RPM-Tach_W0QQitemZ350256858308)for £10 all in.

Now my Jaguar inverter reads out the actual revs of the lathe within 1 or 2 rpm, and I know the mill is 5% faster than the speeds marked on the cover (not that it matters because I have a VFD to be installed for that too)...

tumutbound
22-10-2009, 08:06 AM
I bought one of these eBay cheapies for about the same price ($A24).
It seems to work pretty well although I've no other reference to compare it to.
I've run out of rotating things to stick the reflector tape on.

[The price for mine was actually $A4 and $A20 shipping. If you request a refund, you only get the $4 back. I think the actual postage according to the post office stamp was in the order of $5]

irving2008
22-10-2009, 09:56 AM
I bought one of these eBay cheapies for about the same price ($A24).
It seems to work pretty well although I've no other reference to compare it to.
I've run out of rotating things to stick the reflector tape on.

[The price for mine was actually $A4 and $A20 shipping. If you request a refund, you only get the $4 back. I think the actual postage according to the post office stamp was in the order of $5]
I work on the basis that refunding anything less than £20 from outside the UK isn't worth worrying about. Nice laser diode in there, very bright!

Robin Hewitt
22-10-2009, 12:16 PM
I did later find an even cheaper ebay source (http://cgi.ebay.co.uk/Digital-Laser-Photo-Tachometer-Non-Contact-RPM-Tach_W0QQitemZ350256858308)for £10 all in.

At £9.65 I could not resist, can't exactly think why I need one but looks like fun :whistling: