By continuing to use this site, you agree to our use of cookies. Find out more
Forum sponsored by:
Forum sponsored by Allendale Jan 24th

Machin guards


All Topics | Latest Posts

Search for:  in Thread Title in  
Jonathon Bywater13/06/2021 16:15:14
18 forum posts

Wondering what clear plastic to use as machine guards. Acrylic shatters I believe so something bendable ! Thanks.

Russell Eberhardt13/06/2021 16:24:05
2695 forum posts
86 photos



Jonathon Bywater13/06/2021 16:33:26
18 forum posts

Thank you Russel

Rod Renshaw13/06/2021 16:52:18
301 forum posts
2 photos

Acrylic is said to go opaque after some years of contact with cutting fluids.

Jonathon Bywater13/06/2021 18:01:52
18 forum posts

I think acrylic shatters to . Nice!

Bill Pudney13/06/2021 23:27:49
559 forum posts
24 photos

Polycarbonate a.k.a. Lexan is what you want. Acrylic a.k.a. Perspex or Plexiglass does shatter, Polycarbonate doesn't.

Polycarbonate is used on industrial machines when a cheap transparent guard is required. Armoured glass is possibly more resistant to impact but more expensive.



Jeff Dayman14/06/2021 00:05:18
2166 forum posts
45 photos

Lexan is Sabic's brand of polycarbonate ( Used to be GE Lexan, but General Electric Plastics was bought by Sabic in about 2007 as I recall)

Makrolon is Covestro's brand of polycarbonate (Used to be BASF Makrolon, but BASF became Covestro in about 2011 as I recall)

Local to me, Makrolon sheet is much cheaper to buy than Lexan. May be wise to shop a bit where you are, when buying polycarbonate sheet.

old mart14/06/2021 16:36:52
3316 forum posts
203 photos

I made some guards out of 6mm polycarbonate sheet for the museum's mills simply because it was available laying around. Slightly overkill, as 3mm would have been easier to work. The arm holding the screens is a cheap adjustable arm stand for flat screen monitors up to about 19".


Jonathon Bywater14/06/2021 23:47:41
18 forum posts

Interesting. Thank you

not done it yet15/06/2021 07:29:11
6282 forum posts
20 photos

Doesn’t it depend on what one is guarding against? Guarding against splashes, physical contact with moving parts, or prevention of projectiles escaping into the main workshop need different approaches.

David Jupp15/06/2021 08:28:14
784 forum posts
17 photos

If using Polycarbonate for guards, never use acetone for cleaning. It leads to severe stress cracking.

mgnbuk15/06/2021 08:39:14
1031 forum posts
69 photos

Doesn’t it depend on what one is guarding against?

No, not really.

The OP requirement was for a clear plastic material & for a machine tool application polycarbonate sheet covers all bases, so why consider anything else ?

The only real disadvantage to it is that it scratches if you are not careful cleaning it. Some polycarbonate is available with a scratch resistant coating & industrial machines sometimes use a safety glass / polycarbonate / safety glass sandwich to give more resistance to scratching, but the downside to that solution is that an impact from a broken tool or job coming out on a lathe cracks the glass & replacements are expensive. And heavy.

Nigel B.

noel shelley15/06/2021 10:30:31
720 forum posts
19 photos

A good cheap sorce would be to try a sign maker , I once came home with a large amount for a £5 in colours as well, some was 12mm thick. For off cuts try AMARI PLASTICS, in the UK. Good Luck, Noel.

old mart15/06/2021 14:27:29
3316 forum posts
203 photos

To bend polycarbonate, a hot air gun will do, my efforts with the 6mm were not very good, but thinner material should be easier. I tended to overheat the bend line, the picture of the guard with bent ends does not really show the poor bends. Practice with a small offcut would help a lot.

Jonathon Bywater18/06/2021 20:52:11
18 forum posts

Sorry ,had no signal for 2 days!msinly to stop oil and swarf flying at me. Most things I do a pretty small so polycarbonate would probably stop it. Never happened yet.I still wear face protection too,!

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

Latest Forum Posts
Support Our Partners
Eccentric July 5 2018
walker midge
JD Metals
rapid Direct
Eccentric Engineering
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