Acrylic vs. Non-Acrylic Finishers?

[superpacker]

Been reading anything I can get my hands on about the dyeing process, and working on improving my own dyeing abilities, but the finishing step (pun intended), has me curious. There seems to be two clear camps - acrylic versus non-acrylic. The acrylic camp says that crocking and dye rub off is just a fact - it will happen, so an acrylic finish is necessary as most non-acrylic finishes are only partial waterproof. So if the item will see any moisture, e.g., holsters and tack, a permanent moisture barrier is needed, and that means acrylic, plain and simple. The non-acrylic camp asserts that dyes today are much more color fast, so only a temporary or wax-based finish is needed, and acrylic finishes either ruin the look and feel of the leather up front, or will eventually crack and ruin the leather later by taking some of the top layer with it. I know this is certainly a "to each his own" thing, but I'd love to hear thoughts and opinions and experiences. If anything as a repository of anecdotes for those new to dying. 

[Northmount]

Also consider lacquer based.  They are longer lasting and more waterproof than wax and oil based finishes, which really aren't a finish, but are instead treatments to keep leather soft and pliable, reducing the tendency to dry out over the years. 

So maybe the poll should differentiate between lacquer and wax/oil treatments instead of just stating non-acrylic as the 2nd option.

Tom

[superpacker]

Good point. Doesn’t appear that I can edit the poll now. Bummer. Thgouhts are still welcome!

[fredk]

I use both on the same items.

I've never heard those reasons you quote. I wouldn't agree with any of them

[superpacker]

that’s good to hear because I’ve thought of trying a layer of waxed based conditioner before laying down an acrylic finisher but wasn’t sure how well it would adhere 

[fredk]

I do it other way round; I seal with some coats of diluted resolene then burnish in a beeswax/neetsfoot oil mixture

[YinTx]

On 7/27/2018 at 10:59 AM, superpacker said:

that’s good to hear because I’ve thought of trying a layer of waxed based conditioner before laying down an acrylic finisher but wasn’t sure how well it would adhere 

I've done this, it seems to work ok.  But the conditioner has to basically soak all into the leather, and not be sitting on top, so for example laying a heavy layer of beeswax and expecting an acrylic finisher to adhere on top of that is kinda silly.

I have wondered about putting a conditioner on top of acrylic:  how does it help the leather?  Is it able to get through the acrylic and into the leather?  Or does it just tone down the plastic-y look of the acrylic?

I also like the clear-lac finish, but it is pretty harsh stuff, so lots of ventilation, and in my experience it will streak antique like no tomorrow if you don't spray it on.

I need an "all the above" button to vote.  Just depends on what I am making and how I want it to look.

YinTx

[fredk]

1 hour ago, YinTx said:

... I have wondered about putting a conditioner on top of acrylic:  how does it help the leather?  Is it able to get through the acrylic and into the leather?  Or does it just tone down the plastic-y look of the acrylic?

Science lessons time.

Leather is made of lots of fibres, criss-crossing every which way. There are packed together in layers, looser on the flesh side getting tighter on the grain side. When you apply dye the dye attaches to the surface of the individual fibres. Dye applied to the flesh side soaks in quickly as it can penetrate the gaps between the fibres; put enough on and it'll dye the grain side eventually. The compactness of the fibres on the grain side doesn't leave any space for the dye to run into. Wetting or dampening the leather opens up the fibre structure and allows the dye to flow.

'Acylic' is used as short hand for the dyes or sealant. The colour or sealer is an acrylic resin in a carrier, usually for us its either alcohol or water. When the carrier evaporates off the resin hardens. There is actually very little resin in the mix. After dyeing, when we put on thinned coats of acrylic sealer, it attaches to the fibres like the dye and hopefully it locks the dye onto the fibres. But there is still gaps between the fibres. Room enough for beeswax and neetsfoot oil mix to be rubbed it. Putting on the BwNFO first I think fills in too much of the gaps not allowing the acrylic sealer to get to the fibres

Did you do science at school? Did a teacher ever do the 'Is the bucket full' bit?

First he puts a load of golf balls into bucket. Is it full ? Yes we say, Then he pours a load of ball bearings into the bucket. These fill the gaps. Is it full? Yes. Then he pours in a load of sand, which fills more spaces. Is it full? Yes. Then he pours in water till its up to the brim. Is it full now ? he asks .....um, not sure now.

Thus with leather; theres lots of room for more liquids to be added.

[superpacker]

Fredk, great comments. So it sounds like it’s possible to condition a leather item post resolene finish? Is there any benefits? Also, if I use neats foot oil after dye (not beeswax), to condition and even dye spreading, then use resolene on top, will that still allow for a conditioner to go on top? Say something like Skidmores which is a beeswax based with a lotion consistency? 

[YinTx]

10 hours ago, fredk said:

'Acylic' is used as short hand for the dyes or sealant.

Sealant is the keyword for me.  I look at it this way:  if the acrylic seals out small molecules like water, it is sealing out larger molecules like beeswax also.  I can put drops of water on the acrylic sealed leather, it just sits on top.  I suspect the large molecules of NFO/Beeswax mixture is sitting on top as well. When I put water on leather treated with NFO/Beeswax, it still soaks in pretty fast.  Tells me I still have room to put the acrylic on top if I need it and it will set into the leather as needed. NFO/Beeswax and other conditioners are just that, conditioners, not sealers.  At least this is my view and experience.  Again, the joy of leather work is you do what works best for you, on the types of leather projects you make!

YinTx