I’m just starting out and was looking at this U Pol S2025 primer sheet
https://u-pol.com/wp-content/uploads/S2025B1-TDS-EN.pdf
I’m confused by the mixing ratio on the sheet saying 4:1, then saying in grams 200g:29g (2032 Hardener).

How is 4:1 not 100g:25g (or 200g:50g)?

I’m puzzled!

TIA

The specific gravity of one of those components is not = 1.0

OldFatBald wrote:The specific gravity of one of those components is not = 1.0

Thanks.

So is it that if you aren't mixing by weight, then you must purely go by volume?

Conversely if you are mixing by weight you must really have the spec sheet info? Or are there "rules of thumb" on using weight/scales through experience?

Silver50 wrote:if you are mixing by weight you must really have the spec sheet info? Or are there "rules of thumb" on using weight/scales through experience?

Correct. Specific gravities vary, even amongst similar products from the same manufacturer, let alone different manufacturers.

Mixing by weight is much more accurate, essential when mixing colours. Not quite so important when mixing clear/hardener/reducer when using volumes (i.e. a measuring cup) is sufficient. That said, I like to measure by weight and do so for all products that show the weights on the TDS. Where weights/volume are not shown I measure out, as accurately as possible, say 100ml of each component, and record the weights so I can repeat later on the scales.

just get an assortment of mixing cups then use the oz markings, this is oz by volume thats all you need. 4-1, fill the cup to the 4 oz mark and ad 1 oz of activator. if you want 8 oz of paint then it needs 2 oz of activator. if it needs reducer say 4-1-1 then 4 oz of paint 1 oz of activator and 1 oz of reducer, you can build from there. if you can still get them a smart stick works relitivly good. a have used inches before, 4" of paint and 1" of activator. inches are handy when mixing an unknown amount of paint in a gallon can.
Jay D.

https://u-pol.com/wp-content/uploads/S2025B1-TDS-EN.pdf say under preparation no abrasion required with E-Coat, i'm not buying that!!!
Jay D.

Thanks for the guidance

Someone I know has given me some practical tuition but other than that. been soaking up a info on youtube. But measuring tuition/guidance has been a little bit thin on the ground.

I'm glad I came across the above because I have some scales I was going to use and I probably would've got the ratio wrong while thinking I was being clever/more accurate!

Silver50 wrote:Thanks for the guidance

Someone I know has given me some practical tuition but other than that. been soaking up a info on youtube. But measuring tuition/guidance has been a little bit thin on the ground.

I'm glad I came across the above because I have some scales I was going to use and I probably would've got the ratio wrong while thinking I was being clever/more accurate!

A few things that I have learned as a non-pro weekender hack:
A) Stay off of YouTube - ask the pros here. These guys have YEARS of real world knowledge that they will share with you if you just ask. You may not like some of the answers, but they will not BS you.
B) Get some mixing cups as mentioned above https://www.amazon.com/gp/product/B0B31 ... =UTF8&th=1
Mixing by weight is great if they give you the weight ratios like in your example
C) Just start doing it, take notes, take photos, post mistakes and questions.
D) Have fun - I have learned quite a lot from this forum

OldFatBald wrote:

Silver50 wrote:Thanks for the guidance

Someone I know has given me some practical tuition but other than that. been soaking up a info on youtube. But measuring tuition/guidance has been a little bit thin on the ground.

I'm glad I came across the above because I have some scales I was going to use and I probably would've got the ratio wrong while thinking I was being clever/more accurate!

A few things that I have learned as a non-pro weekender hack:
A) Stay off of YouTube - ask the pros here. These guys have YEARS of real world knowledge that they will share with you if you just ask. You may not like some of the answers, but they will not BS you.
B) Get some mixing cups as mentioned above https://www.amazon.com/gp/product/B0B31 ... =UTF8&th=1
Mixing by weight is great if they give you the weight ratios like in your example
C) Just start doing it, take notes, take photos, post mistakes and questions.
D) Have fun - I have learned quite a lot from this forum

Thanks will do. Got some mixing cups but they’re a bit small!!

Admittedly some YouTube is better than others. I would say I’ve taken quite a lot from it as a whole rather than taking particular note from any one channel.