By continuing to use this site, you agree to our use of cookies. Find out more
Forum sponsored by:
Forum sponsored by Forum House Ad Zone

Something to ponder 02

All Topics | Latest Posts

Search for:  in Thread Title in  
<< First < Prev 1 2
Michael Gilligan14/07/2011 23:39:50
avatar
23121 forum posts
1360 photos
Richard,

Oops! ... I hadn't realised the scale of the planer you are building.
Given that this thread started as a discussion about a microscope stage, I foolishly presumed you were making a miniature, for watchmaking! [hence my concerns about contamination of the bearings].

It sounds like a very interesting project.
Do please keep us informed.

MichaelG.


P.S.
You said "I just cut and pasted the name on your post."
... Just for clarity; Michael, or MichaelG. is fine.
... it's short-forms such as Mike that I don't use.
alan frost15/07/2011 01:22:53
137 forum posts
3 photos
Ah,thanks for inputs on piezo. The one I vaguely remembered was long travel and as I remember it the piezo gave a small twitch which was then" anchored" in some way ,then another small twitch ,anchor again and so on.
Using stepper type waveforms one could presumably fairly quickly do quite a long traverse. Maybe two piezo crystals were involved , twitching and "anchoring " in turn. Problem is it would lose precision with many" twitch and anchor" sequences as any error per step would be accumulative although the error as a percentage of travel would remain constant.
Anyway I feel quite a warm glow knowing ,thanks to your inputs, piezo materials are used for precision movement of microscope stages.
As a matter of interest one of those gadgets that cuts microscopically thin slivers of specimens for microscope viewing ( I can never remember the somewhat illogical name of the damned things,its a sort of precision bacon slicer-you know what I mean ah-its coming back to me a microtome ? ) also has a very precise and small incremental movement ,
The one I salvaged from the local university's skip achieves this with a very fine and precise screw thread with zero or very little backlash ). One of these days I'm going to convert it to a device for slicing quarks off hadrons ,or at least electrons off atoms. Then I'll be famous and as I intend to start with a fairly beefy atom, slicing one proton and one electron off the one up from gold, quite rich too.
. Regards

Edited By alan frost on 15/07/2011 01:37:43

Edited By alan frost on 15/07/2011 01:40:05

Michael Gilligan15/07/2011 08:08:44
avatar
23121 forum posts
1360 photos
Alan,

( I can never remember the somewhat illogical name of the damned things,its a sort of precision bacon slicer-you know what I mean ah-its coming back to me a microtome ? )

That's a lovely functional description of a Microtome!
... and, evidently I don't dive the right skips.

You are probably right about the "Twitch and Anchor" [*] mechanism; but I confess that I have not seen one.
The folks that fabricate Integrate Circuits on on Silicon wafers use some amazing electro-mechanisms.
Also, some camera lenses use Piezo-drive for focus.

Must investigate further.
... I will report back if I find anything of interest.

MichaelG.


[*] The Twitch and Anchor sounds like a good Pub name.
Michael Gilligan15/07/2011 08:20:01
avatar
23121 forum posts
1360 photos
I have just found this catalogue:
http://www.labhoo.com/brochures/B9006_Microscopy_Stage_CatalogV79b_C.pdf

Sixty pages, but downloaded very quickly.

Some very interesting kit, and good sketches.

MichaelG.
Michael Gilligan15/07/2011 08:33:22
avatar
23121 forum posts
1360 photos
See also:
http://www.physikinstrumente.com/en/products/linear_actuator/piline.php

alan frost15/07/2011 20:48:49
137 forum posts
3 photos
Michael
 
You'd be amazed at what the local university throws into skips. . Hospitals, the military and educational establishments all buy top quality stuff and bin it at the slightest excuse (well, its only taxpayers money after all). A while back my skip diving partner (he enters the skips with a rope round his ankle and I stand by with my engine crane in case he needs to be hauled to safety ) and I could have had an electron microscope and at about the same time we rescued about 10 Oertling precision balances. We would have walked the Nobel prize for weighing had we entered..Top quality benches and chrome plated storage racks on wheels are common fare,
Mind you its not all easy work -the university is very disorganised and often throw out beautiful benches but do not always bother to keep matching legs and bench tops together. Disgraceful!! Do they think that as pensioners we have all day to sort this stuff?A while ago I rescued a double beam oscilloscope , thinking I'd have to do a few repairs. I was right I had to put a plug on it. It had failed the Elfin pastry electrical tests. Well I come from Bill Bryson's indestructible generation (grew up in solid smoke , did n't have a little safety seat or crash helmet ,swam in polio infested swimming pools etc. etc ) and its fine for me. Selfishly the University tends to hang on to the higher bandwidth models.
 Other rescued items include lots of electric motors, about 200 metres of stainless steel (8 ton breaking strain) cable etc. My friend when he built his house extension pretty well obtained all his building materials from the University skips. He has some of the most intelligent walls and ceilings in the country.
Regarding the indestructibles ,like all of my generation , my house and everyone else's were filled with smoke , while the local cinemas had difficulty projecting the film through smoke clouds resembling intergalactic dust clouds. How many kids did I know with asthma, hayfever , allergies , or respiratory diseases ? One or two over my entire school life of 15 years. Nowadays half of any class suffer-no immunity-a slight smoke haze lays them low -we could cope with large viscous lumps of tobacco smoke.
Anyway , enuff elderly ravings -must check out your email references given in last postings. Regards

Edited By alan frost on 15/07/2011 20:57:15

<< First < Prev 1 2

All Topics | Latest Posts

Please login to post a reply.

Magazine Locator

Want the latest issue of Model Engineer or Model Engineers' Workshop? Use our magazine locator links to find your nearest stockist!

Find Model Engineer & Model Engineers' Workshop

Sign up to our Newsletter

Sign up to our newsletter and get a free digital issue.

You can unsubscribe at anytime. View our privacy policy at www.mortons.co.uk/privacy

Latest Forum Posts
Support Our Partners
cowells
Sarik
MERIDIENNE EXHIBITIONS LTD
Shopping Partners
Subscription Offer

Latest "For Sale" Ads
Latest "Wanted" Ads
Get In Touch!

Do you want to contact the Model Engineer and Model Engineers' Workshop team?

You can contact us by phone, mail or email about the magazines including becoming a contributor, submitting reader's letters or making queries about articles. You can also get in touch about this website, advertising or other general issues.

Click THIS LINK for full contact details.

For subscription issues please see THIS LINK.

Digital Back Issues

Social Media online

'Like' us on Facebook
Follow us on Facebook

Follow us on Twitter
 Twitter Logo

Pin us on Pinterest

 

Donate

donate