Chat about Novel Coronavirus - 2019-nCoV - COVID-19

We're making reusable visors that can be sterilised using 3D printers at work:

I think they're using different definitions of sterilised. I dont consider alcohol wipes or immersion in alcohol to be sterilisation. The reason for this is that 3d printed parts made from filament have countless tiny bubbles and seams in the finish which can both harbour nasties and shelter them from sterilising fluid. The QMUL ones will have the same problem. Although clearly in the context of usage in this situation they arent worried.

The other problem is that 3d printed PLA and ABS plastics tend to have a plasticity point of around 60 to 80 degrees which is well below what is needed for a full sterilisation. In other words, put 3d printed parts in a steriliser and they'll melt unless you use a high temp plastic like Nylon which provides it's own sterilisation challenges.

Its the nature of the structure of 3d printed items thays the issue rather than the design that is printed

EDIT: this is a good read. Tldr, you cant really sterilise parts unless printed with specialist plastics https://blog.gotopac.com/2017/05/22/sterile-materials-and-outcomes-for-3d-printing-sterile-parts/

EDIT 2: Yes, design is certified by Czech health service. No certification in UK but NHS trusts still seem to want them.

We had just one new case in South Australia.

It could happen quite simply with a cluster that gets out of hand after restrictions are lifted. Unsure of the idea we can lift restrictions and keep spread controlled. Guess at some point the will of the economy will overpower the lockdown regardless, sadly.

idk how people can be so thick. Is staying at home really that fucking hard.

I, along with my team of 5, have been furloughed.
My manager is still working.
I spoke with him yesterday.
"Never been busier" were his words.
Amongst other things, we have four CNC machines, each capable of handling sheet material in excess of 8' x 4'.
They're currently in use around the clock, churning out visors.

Bonkers, eh? I guess we were lucky to be a couple of weeks behind everyone else so didn't make the same mistakes...

How come you've all been furloughed then? And where do you work that's got such tasty equipment? Was eyeing buying a cnc kit the other day... lack of good workspace though.

We produce large format digital print for the retail industry, we also do events, we also distribute film to cinemas.
Do you want a seamless print which is 5m wide and 50m long?
We can do that for you.
All of which has (unsurprisingly) fallen off a cliff.
I'm told we're the biggest outfit in Europe that do this.
We're not short of space. Of the two sites I work at, one is 6 acres, the other is 25 acres.
We have our own snow-plough and gritter.
It's good to see that the kit has been put to good alternative use.
And to see that there's a modicom of a chance that I'll have a job to go back to.

Because the company have worked out a way to have almost same productivity with 5 wages less.

It’s obviously not sustainable but if you’re a small business. Same income but with circa 150k less overheads over a three month period... no brainier.

My housemate has a 3D printer.

I don’t really know; a/ what the need is, b/ where to start.

[I’ve just been furloughed this morning and my vehicle (a furniture van) commandeered (to become a non-emergency ambulance In the Birmingham area). This is disappointing, as I expected to be redeployed and help more directly. I will volunteer but that’s not fully sorted yet and if I can do some useful printing in the meantime ... why not.]

How come you've all been furloughed then?

I work for one of the High St charities with Emergency Teams and plans for disasters (somewhat) like this. I think the idea is furlough most of the staff so the gov helps cover wages, keep most at home, bring certain younger ones back as volunteers (with strict adherence to what they can do - no overlap with the usual job). All Disaster Relief, Logistics, Medical and Services teams have been working non-stop since early March (mostly involved in NHS support and eventually building hospitals, but overseas stuff too).

I think they're using different definitions of sterilised. I dont consider alcohol wipes or immersion in alcohol to be sterilisation. The reason for this is that 3d printed parts made from filament have countless tiny bubbles and seams in the finish which can both harbour nasties and shelter them from sterilising fluid. The QMUL ones will have the same problem.

Barts is one of the country's leading teaching hospitals and centres of medical research excellence, so I'm sure they've given this some thought! Also the sixth prototype was to pass infection control rules, so it seems they must have this sorted:
https://www.standard.co.uk/news/health/visors-dentists-3d-printers-front-line-a4409141.html

That said, the School of Dentistry were very clear that they're doing this because they didn't feel the kit that was available was up to scratch. So this is better, but nobody is pretending that 3D printing your own masks is anything close to ideal.

.

Have we had this yet?
https://www.theguardian.com/world/2020/apr/08/police-chiefs-call-on-no-10-to-tighten-uk-lockdown

Fortunately it suggests that police chiefs are more interesting in cracking down on motorists on unnecessary journeys than cyclists or other people genuinely doing exercise.

I was out doing some fruit and veg shopping just now and this was the thing I noticed the most, lots of single occupancy car drivers driving around. A lot more than earlier in the lock down although car drivers love a nice sunny day don't they?

A lot more than earlier in the lock down although car drivers love a nice sunny day don't they?

The literal second I'm reading this sentence, I can hear some boy racer howling round the corner.

I think single occupancy car drivers aren't necessarily a problem. It's the ones that are have mum, dad, 2 kids, grandma, a dog and some beach towels that are perhaps troublesome.

I probably should have also mentioned that almost without exception they were clearly speeding. And it was pretty obvious that a lot of them were not making essential journeys. This was c.3pm on a Thursday afternoon.

There does seem to be a lot of speeding about but then it's been obvious for a long time that many drivers only don't speed because they can't. In the days past I used to drive to swim early on a Sunday morning and was always overtaken on the 20mph stretches.

I'm not sure the 3pm on a Thursday means it isn't an allowed journey though. I've been doing our family weekly shop in the middle of the day because I can and the shop is perhaps quieter (I don't actually know since I haven't been at other times).

Priti surfaces

And it was pretty obvious that a lot of them were not making essential journeys

How can you tell?
I don't drive but I sympathise with those doing so more now, seems an obvious way to minimise contact.

How can you tell?

Barts is one of the country's leading teaching hospitals and centres of medical research excellence, so I'm sure they've given this some thought!

That maybe, but there is a difference between deciding that a product meets requirements in a particular moment of desperate need as opposed to a product actually meeting standards. I'm not sure what "pass infection control rules" means as it varies so much for what object you are assessing and how it is used.

What I do know, from a consultancy piece I did for a sex toy manufacturer where we made things and had them lab tested (in know, i know), is that freshly printed objects are pretty much sterile due to their printing temperature (200 degrees+), its what happens to that object afterwards that is problematic. Most 3d printing plastics and certainly the ones most people use at home denature on contact with various solvents and cannot be heat treated due to their low plasticity point. This is why I am so sceptical that a 3d printed visor could be reused without lowering hygiene standards. I freely admit that inserting an object into a bodily cavity for pleasure purposes is a different use case than hanging an object off your face for infection control :D

On the subject of what Barts and QMUL are currently doing, I understand that they have reached an agreement with Halma who are going to produce their design using injection moulding so they can get away from the problems introduced by 3d printing. EDIT: Being slow production speeds, fragility, infection control.

Slightly devil’s advocate here but what’s the problem with driving? Other than all the usual problems with driving.

https://www.bmj.com/content/bmj/369/bmj.m1435.full.pdf

Finally an article arguing that the precautionary principle should be applied to mask wearing guidance for the public