Edge finishing chrome-tanned leather

[SUP]

I recently finished a bag of chrome tanned leather and over some frustrating weeks, learnt first-hand how edge-finishing chrome-tanned edges is different from edge-finishing veg-tanned leathers.

This is what I experienced: 

I had to stitch 4 layers of chrome-tanned leather together. It is evidently a split with synthetic coating. No matter how hard I tried, the edges of the 4 layers could not be cut exactly level to provide a single smooth, level edge. I had to edge finish.

Not being veg-tanned leather, I could not use Tokonole or gum trag and burnish it, so  edge paint it had to be. But that paint looked ugly and rough, so I had to sand it down.

But sanding damaged the synthetic material and leather giving an even rougher texture, so I realized I needed a primer.

The primer, a single thin coat, did not do much. It was still very rough and sanding still made a mess.

So I applied another thin layer, and another and then sanded. By now, the primer layer was sufficient to coat the edges of all the 4 layers well and I could sand down until I reached the leather in the edges of all 4 layers that were the highest and left the remaining sections of all the edges untouched.  I applied primer again. And repeated. By now, the lower sections of the edges of all 4 layers had built up to be more or less level. When I sanded next, they were level.

I painted, sanded lightly and painted again, and got a reasonably nice edge. I could have continued to get a really shiny beautiful finish but stopped there.

Through the process, I learnt this about chrome-tanned leather edge finishing.

I need to build up the edge to the highest level using a primer and then paint the edges, so that it is smooth. This is the opposite of what we usually do with edge-finishing veg-tanned leather, where we flatten the leather using  beeswax or other agents. 

Now peeling can be a real issue when building up layers of primer and paint – it is after all only acrylic something. That is why I kept sanding as much as possible only until the lower layers built up. As sanding roughens the surface, that also helps a bit to hold the paint in place. I’m still not sure whether thicker coats of primer and paint are better or thinner ones since there are proponents of both. My primer is a bit thick so I could not make a very thin layer. I made it as thin as possible. Now only time will tell how it works out.

All this is surely known to experienced leatherworkers. I could not find it anywhere - probably more an oversight on my part since I am sure there will be some kind souls out there who will have explained it much better.

For me, knowing why I do something helps me do it better. That is why, once I understood the principle behind using those primers and paints, I thought I would share it here.

I would love to hear more about this from all who have been using this for years.

 

 

 

 

[NatesLeatherGds]

Good info. I frankly just never do it - maybe a bit of tokonole and then leave it be. So much trouble! Thanks for the data on how you did it. 

[bruce johnson]

There are a few commercial edge treatments that do OK on chrome tan - Martin's Mix and the one Sara Hagel sells. My wife uses Sara's version. I used this procedure. I applied a thin coat of acrylic finish (LeatherSheen, SuperSheen, or Mop-N-Glo). Let it dry and apply another light coat and dry. Then run some fine sandpaper over the edge until smooth. If I edge painted, then this made a nice base. If I wanted a more natural edge then I used wax (you pick - beeswax, paraffin, or Yankee wax). You can rub-rag the wax or heat it with an edge iron. 

[SUP]

@NatesLeatherGds, thank you.

@bruce johnson I've not tried wax as yet. I needed a bright matching color for the leather. Mixing  colors to get a match was a pain and acrylics look different when wet and dry. I will try wax next. A gentle burnish would be nice. 

I used Uniter's primer and I am happy with it. I will try Martin's mix and Sarah Hagel's product too though. It is good to have a choice.

Only thing is, this leather is of a firm temper, so the stiffening of the edge with the primer and acrylic paint worked. I'm not sure how to keep the edge soft on softer leathers and yet have it edge finished as well.

Edited February 28 by SUP

[Danne]

Now this isn't pure chrome tanned (exterior: Vegetable tanned, interior combination tanned) but this is how I do my edges.

And the second link a wallet that have been used for six years and edges still look nice.

 

[SUP]

@Danne, I saw that earlier. you have shown it so well.  

However, mine was multiple layers of about 4-5oz  chrome-tanned leather, with curves and whatnot, and the leather has synthetic layers on both surfaces. I dare not apply any heat. Sanding directly was not an option, in fact sanding was not an option until it had a good layer of primer on it. Furthermore, with 4 layers, at least for me, the edges were not even and needed to be evened out before I could think of creasing or anything else. The edges could not be evened out by cutting so it had to be by building up the uneven sections. After the edges were leveled out, creasing etc. would have been possible.

[SUP]

I found this video while looking for something else. It shows more or less what I do, although I use a primer at first. I got something from the same place earlier via Etsy.

how to burnish leather edgeseasy&fastبه راحتی رنگ لبه بزن_سریع و آسان - YouTube

 

Edited March 15 by SUP