When to oil?

[mcguyver42]

FredK also mentioned putting a little hot water in the mix.  So if I put say a pint of oil in a pot, how much soap and water?  and we are discussing regular dish washing liquid here?  I feel that I've oiled this leather enough, and that any more would be too much.  Actually it's becoming tan on the back side, and I hope I don't run into any glue stick issues.  Still, I wish there was some kind of test, (A moisture meter on wood for example).  I  compared my dyed and oiled pieces to the untreated portion of the side to try to discern some differences that I could call "tests":  examining the cellular structure of the edges with a magnifying glass, trying to note different sounds when rubbing the back side with my fingers and fingernails.  I couldn't pinpoint any notable differences. The grain does appear to be thinner and more defined on the oiled pieces, but that could just be the dye.  I think the expected weight when you pick up similar sized pieces is a little different.  The oiled pieces do make more of a satisfying smack sound when I drop them onto the workbench.  A thumbnail impression is definitely more self healing on the non oiled pieces.  I know that I'm over analyzing, and should just let experience take it's course, but I bought quite a lot of leather in the beginning.  It wasn't top quality to begin with and it's been in storage for 3-4 years.  I'm concerned with losing the whole lot of it if I don't learn how to take care of it.  When I say storage, I mean in the house under heat and air and out of the light.  I'll try all of your suggestions, definitely oil with soap before I cut out and dye the rest of the pieces.  At least it reassuring to know the curling is normal,  I appreciate the experience and encouragement.      

[mcguyver42]

If I understand Burkhardt, are you saying that you oil leather that is already in good condition before dyeing as a sort of damage control, and then again after?  Mine was dry to start with.  It sucked the dye right out of the sheep's wool as soon as it touched, I couldn't control it.  I used so much light brown dye that it ended up chocolate.  But going back to that water thing, I didn't know how much soap to use and didn't want to overdo it, so I just cased it real good with water.  You and Chuck both said that the surface tension would be reIeased during normal handling over the course of the build.  But,  I worked it through folding the edges back gently, and not being overly forceful as you said.  I cupped my hand over the interior portions and used my fingers to push up some from the bottom.  I could see a pull up effect on the leather when I was doing that and could feel the leather relaxing.  lo and behold, it lays nice and flat.  I let it dry overnight with a cutting board laying on top of it for good measure.  The picture is from the next morning.  Problem solved!   I'm looking forward to finding a recipe for the oil, dye and water if anyone has one.

[mcguyver42]

Update for what it's worth.  I'm a beginner so verify anything that I say.  For me,  I think I found my test to see if my veg tan leather needs to be oiled  Find a waste spot on the leather and scratch a  short line.  It should emboss a line instead of just scratching through the top of the grain.  oil if needed without being too heavy handed as Fredk cautions, wait the requisite 24 hours and retest.  I did that on the side under discussion, and my knife slices right through in one light to medium effort pass with maybe a fiber or two hanging on. 

[dikman]

Good stuff! But the reason it finally worked is because the cat put in an appearance. Everyone knows that cats are magical/mystical creatures.

[Burkhardt]

12 hours ago, mcguyver42 said:

If I understand Burkhardt, are you saying that you oil leather that is already in good condition before dyeing as a sort of damage control, and then again after?  Mine was dry to start with.  It sucked the dye right out of the sheep's wool as soon as it touched, I couldn't control it.  I used so much light brown dye that it ended up chocolate.  But going back to that water thing, I didn't know how much soap to use and didn't want to overdo it, so I just cased it real good with water.  You and Chuck both said that the surface tension would be reIeased during normal handling over the course of the build.  But,  I worked it through folding the edges back gently, and not being overly forceful as you said.  I cupped my hand over the interior portions and used my fingers to push up some from the bottom.  I could see a pull up effect on the leather when I was doing that and could feel the leather relaxing.  lo and behold, it lays nice and flat.  I let it dry overnight with a cutting board laying on top of it for good measure.  The picture is from the next morning.  Problem solved!   I'm looking forward to finding a recipe for the oil, dye and water if anyone has one.

Veg tanned is a raw unfinished leather so some people add a little soap in the water for stamping and also carving, the soap works as a lubricant. Yes, oil the leather before you dye it so the alcohol in the dye doesn't make it stiffer and the dye will absorb more evenly. Any veg tanned leather should be oiled at some point to prevent cracking and falling apart.  

[mcguyver42]

I gotta try to design some gusset's now, I better up the cat treats

[Northmount]

@mcguyver42

I'm a little late to this discussion. 

If your leather curls too much for your comfort when laying out and cutting, moisten the leather enough that it doesn't curl.  Lay it out so the curl is facing down.  You might need to place something on top to help flatten.  Let it dry flat.  Leather will tend to curl while drying.  Be careful what is against the grain side of the leather as it may transfer a pattern to the leather.  Even paper towel will leave a pattern, so your surface needs to be really smooth.

I use a pencil or pen to lay out my cutting lines.  Make sure the lines are not going to be seen in the finished product.

Moistening or oiling before applying dye helps to get a more even coat of dye.  To me, it is better to have the dye absorbed more slowly so you don't have dark patches where your sponge or sheep wool touched down.  Then it is much easier to get a more even dye job.  It may take a couple additional dye applications to get it completely even.  If you want the finished dye job to be light, dilute it a lot first.  Each time you add dye, the leather gets darker.  Hard to make it lighter when it's already too dark. It is also wise to dye all pieces (of the same batch of leather) at the same time to reduce the variance between parts when assembled.

I like to dip dye.  But it is hard to get a light dye job when doing that.

Another option for applying dye is to use an air brush.  There are cheap ones around that do adequately for applying dye to a large area, not trying to do fine detail like some fellows do.  My skills are just for broad coverage.  Don't have the coordination for detail.

Make sure your cutting blade is really sharp.  The angle of the blade edge needs to be quite shallow so it doesn't act like a thick wedge.  It's not like cutting meat where the meat is soft and deforms easily letting the knife through.  There are lots of posts about sharpening knives.  Pay attention to "scary sharp"!

[mcguyver42]

Sounds like diluted dye applied with an airbrush might be thriftier too.  At $25 - $30 a quart this stuff gets pricey in a hurry.   And not all bottles are full by the way, some up to the cap, and some 1 1/2" down the neck.  We are talking fluid oz. here, so I don't know?  I've seen powdered dyes offered by some suppliers that you mix up with denatured alcohol.  Denatured alcohol is out of control now though, mostly methyl alcohol, and who knows what else.  Woodworkers don't want to use it in their shellac anymore, and are resorting to Everclear if they can get it.  The same applies to us.  Between that and the alcohol drying out the leather, it's making me want to take a hard look at water based dyes.  Or other ways to dye leather?  Any input on that?