[VitalikButerin]

Interesting they only charge £43

https://cosmetic-testing.com/product/microbiological-specifications-test/

[VitalikButerin]

@Bill_Toge do you know whether a chemist is required to write out a toxicology report? Or can data from a microbiology test be used 

FYI here’s a decent lab: Oxford Biosciences offers cosmetic product challenge testing for £150 per product.  The tests are commonly referred to as Microbial Challenge Test (Challenge) and Preservative Efficacy Test (PET) but they are the same test.

https://oxfordbiosciences.com/testing/

[VitalikButerin]

Hi mate 

Not bad price for a lab homogenizer, search on eBay too 

[VitalikButerin]

yes such large companies have exclusive distributors 

[VitalikButerin]

for a home business any reputable scale should be fine they give the +/- on the scale. business is expected to be 4% within the given range.

many people use chinese lab scales which work fine for them too. 

[VitalikButerin]

Is there a chance the client finds out? If so how? 

Also formulas unless are really unique are not that special 

[VitalikButerin]

Dtdang said:

I have question:
1) all ingredients that are water soluble are mixed well with stirrer
2) all ingredients that are oil soluble are mixed well with stirrer.

 Now 1) and 2) are put together for emulsion 
Question: should I use stirrer or homogenizer?

thanks in advance 

Homogenizer of course 

[VitalikButerin]

Stirrer just stirs. 

Homogenizers like emulsifyers aim to combine the two difference molecules into one mixture. Like powders and oils, it really breaks them down a lot more whilst spinning them, not only just by stirring them 

[VitalikButerin]

Dtdang said:

Southwest science has sos20 digital mixer costs 390 usd but it can handle up to 20 liters and the shaft diameter from 0.02 to 0.375 inch

that’s just a stirrer and not a homogenizer - i would rather DIY a stirrer 

[VitalikButerin]

marinda0070 said:

How many watts should a decent lab mixer have? 

2980 rpm 

Depends on how many liters you want to mix 

[VitalikButerin]

Hi belassi 

I actually found a number of suppliers, I can probably send it to you. 

Please inbox me 

[VitalikButerin]

Hi belassi,

This is because it is a drug, I doubt you can use it in formulas

[VitalikButerin]

My advice is, if you buy machinery from China make sure you understand how the machine works to know how to fix it 

Also you don’t always have to go expensive, the best is to go simple

[VitalikButerin]

If you have a company set up, it’s not hard to request samples. 

You shouldn’t expect any credit though so everything you’d have to pay for up front of they request money - on samples not sure if they give 1 litre maybe 100ml 

[VitalikButerin]

In truth, you need to audit the supplier from AliBaba first 

They can send you anything and you won’t be able to verify it 

[VitalikButerin]

There are auction websites, Ive even seen silverson second hand with all the parts for £800

I understand this is not homogenizer, but this is a used auction website ; but let me tell you, eBay auctions are always cheaper! 

https://www.equipnet.com/ika-rw-20-digital-lab-mixer-listid-609987/

[VitalikButerin]

That’s very expensive £600 you can buy second hand one for that price of   good brand 

I’m guessing this is a lab one?

[VitalikButerin]

How much 

[VitalikButerin]

chemicalmatt said:

The rotor/stator head on the left most closely matches the industrial scale units we have in general use. Silverson carries different shear-head combos for these. Missing from this thread is scale-up speed. Virtually all powered industrial homogenizers run at 3500 rpm, and that is with a 15hp/460V/3phase motor. A scant few may go to 6000 rpm. I’ve had to school many a bench chemist on this when they say “Wheee, look how well it worked at 15,000 rpm!” If you cannot scale-up then why bother unless it is for home use?

Do you use Chinese made ones or silverson ones? 

[VitalikButerin]

Anyone? 

[VitalikButerin]

MarkBroussard said:

@angelz:

I use both of these types of homogenizers.  The homogenizer on the right is really good for making small samples … 300 grams or so.  But, I had to have a machinist build a custom “emulsification cage” for it because that homogenizer head, as designed, pulls lots of air into your emulsions.

So, basically, I had a machinist make a “Silverson Workhead” with an emulsor screen (just like the homogenizer on the left) that fit onto the homogenizer on the right.  Solved the problem.

How much did this cost to reverse engineer,? 

[VitalikButerin]

Find a manual and follow it 

[VitalikButerin]

Herbnerd said:

You have to be sure of the company before buying - it really is buyer beware in China unless you have someone on the ground who knows what they are doing and the best companies to deal with. There is rarely any come back if there is a problem.

A company I worked for bought an in-line homogeniser for light work (incorporationg aloe powder into water), in which there was a hopper to pour the powder into. It didn’t do the job. The only way they could get it to work was to put another pump in-line to pump the liquid through the homogeniser first - which defeated the point of buying one in the first place.

The other thing to watch out for is the bolts - they tend to be mild steel and will shear off quickly. Best thing to do is replace all bolts beofre you start using it.

Thankyou for that, but I’m interested in the basic homogenizer, for example: 
https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F382053593170

Ebay /paypal should gurantee.. 

However I’m wondering if they’re good enough to make creams? 

[VitalikButerin]

@Perry  thanks

@Bill_Toge  Do you offer this service ?

[VitalikButerin]

It’s a scam site 

https://uk.trustpilot.com/review/pearsandpeaches.com