Edge Coat 4. Using Primary

BAEL LEATHER SCHOOL
Sep 4, 2018 · 3 min read

Have you ever had difficulties to apply edge coat neatly due to the section difference of the leather? When you combine several leathers, grooves can be made or it can be uneven even if boding is done properly.

Well applied edge coat is the condition in which solutions are applied evenly and the surface is smooth. So if there is groove or grains, outcomes of edge coat will not be good.

After all, we need to perform cutting and right angle cutting very neatly from the beginning and make sure not to make section difference after bonding to make edge coat work will be easily.

There are two ways to cover the grooves and grains that can be made.

1) Remove the section difference by grinding the cross section with strong sandpaper

2) Remove the section difference by filling the groove with specific solution

The first method is to grind all the leather and flatten the cross section. In this case, the original shape may be deformed.

The second method is to apply specific solution before edge coat. If you apply this thick and colored solution that doesn’t have color when dried before edge coat, you can fill the groove or grains to make the cross section flat. This is called as primary or base coat.

For reference, there is a solution called Top Coat that can be applied to adjust the gloss or protect the color after applying edge coat.

The photo shows the primary of Fenice. Every company produces edge coat also produces the primary. Italian product has a urethane features, so it looks thick when applied. On the other hand, Japanese product which I couldn’t use yet is a little thinner than Italian one. I think if the product has more features of urethane, the effect will be larger. But if you don’t like the work that looks like an industrial product with thick edge coat, Japanese products will be ok.

I’ve used primary in fact, but I threw all of them away since I didn’t like it.

For reference, edge coat solution itself includes the features of base coat. So it is considerably thick. French L Company uses this product.

The use method is very simple.

Apply the primary first on the cross section you want. The color becomes colorless over time.

When you apply it, be careful to use sticks or rods like awl rather than magic block.

Unlike the watery edge coat, this thick ingredient just permeates into the magic block and will not come out.

Then, you need to dry it enough. This is because the thick ingredients are not easily hardened unlike the edge coat. You can apply it several times if necessary. If the groove is deep, you need to fill it up and dry repeatedly.

After that, you can apply and clean it in the same way as applying ordinary edge coat.

Lastly, primary is used to make thick cross section from the very beginning in addition to its function to fill the grooves.

But if you use too much, if can be easily torn out.

Or if the edge coat to be applied on the primary is too thin, the color is not clear and the primary may be exposed. In this case, the product is not good.

The best thing is that the cross section of the leather and the solution is tightly attached so that the cross section is not easily exposed to the friction in everyday life.

In that sense, please be aware that if you don’t use the primary well, it may deteriorate the quality of the product.

BAEL LEATHER SCHOOL

Written by

Participating in the work of leather crafts, writing and lecturing at BAEL Leather School after completing 'La Scuola Del Cuoio' in Italy.

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