Balsa vs Leather? Big confusion on my part!

[stitchawl]

I keep reading these threads and I keep seeing comments that the balsa is more firm than the leather... And I'm getting pretty confused!

What kind of balsa are you using?!? In my mind, it's the blocks or sheets of balsa used for model making. But that stuff is MUCH softer than any leather strop should be! I can easily score that balsa with light pressure from a fingernail. I'd have to really bear down with a fingernail to do that to a good leather strop. What am I missing here? Are you using some special type of balsa?

I've seen several strops being sold in knife sharpening threads that were just plain cowhide glued to a fancy paddle. The leather wasn't treated in any special fashion, but that fancy paddle and block of compound certainly raised the prices. Is THAT what you are thinking of when you say that the leather will curl around the edge? Obviously, it will. Most of them don't use compressed leather. (Note that I say 'most,'... not all.) But just as obviously, those things shouldn't be called 'strops!' They are just soft substrates for compound. Might as well use a copy of National Geographic (which, by the way, works really well as a finishing strop due to the clay used to make the shiny coated pages!)

If you can press your blade down into your strop so that the leather is able to curl up over the edge, get/make a better strop! But first, please tell me about this extra firm balsa!



Stitchawl

 

[yoda4561]

Same stuff. The balsa is actually more rigid than leather is, it is however a bit easier to damage as it doesn't have any elasticity to it. It's light, low maintenence, and cheap to make a strop in whatever shape you want out of locally sourced material. This comes in handy with odd blade shapes or wood carving tools. You use it in the same fashion as a leather strop, when you need to resurface you can just sand the surface down or glue a new piece on. With a wide contact area like a knife or chisel you won't deform the surface like your fingernail does, and it's also less prone to rounding off edges from using too much pressure on the strop.

 

[stitchawl]

and it's also less prone to rounding off edges from using too much pressure on the strop.

Then again I'll say that if you can round the edge off with your leather strop, the leather has not been properly processed to BE a strop! It's much easier to press an edge into balsa than a 'properly made' leather strop.



Stitchawl

 

[hoxhunbe]

Some insight: http://www.youtube.com/watch?v=DP2gYS_8IeI&feature=youtube_gdata_player

I think it's partly a preference thing, but the argument that I can find so far is that the balsa, when used ever so lightly, is a bit more rigid than most available and inexpensive (and perhaps by your definition, incorrect) leather strops. I don't have any experience with stropping in general, but I've had the same question and this is all I found so far. Hopefully some of our more practiced balsa stroppers will chime in.

 

[stitchawl]

Good video, thanks! I've been using horsehide strops on my EdgePro for several years now, and love the results I get.

Certainly more rigid, that for sure, as the grain of the balsa is probably running parallel to the length of the strop.
But certainly SOFTER that properly compressed leather, which might also explain why the ancient Romans made their body armor out of boiled and compressed leather rather than balsa wood.

I guess it should be said that a larger blade is going to have less pressure per square inch against the substrate than a small blade, and with that in mind, a small blade might be more damaging to either stropping surface...

I just took an 1/8" piece of modeling balsa and virtually cut it in half with my thumbnail. I took one side and compressed it between my thumb and index finger to half its thickness. I am not able to do either with my 'stropping' leather. I CAN compress a piece of plain cowhide that hasn't been processed, and certainly CAN dig a groove in it with my nail. But that leather is NOT ready to be used for stropping. It's just a piece of leather being used AS a strop. Big difference between the two. One is leather that can be used for any purpose. The other is leather that has already been processed to use for a 'specific' purpose.

So then... does this lead me to suppose that balsa is better than unprocessed leather as a substrate for compound, but not as good (or perhaps is it) equal to properly processed leather, but must be used with compound?



Stitchawl

 

[singularity35]

So then... does this lead me to suppose that balsa is better than unprocessed leather as a substrate for compound, but not as good (or perhaps is it) equal to properly processed leather, but must be used with compound?



Stitchawl

I'd agree that balsa is better than a lot of leather out there but when you get good quality leather suitable for strops, the leather seems to do better.

 

[capid1]

Stitchawl,

You may want to look into trying #30-40 weight balsa. Most modeling balsa in hobby stores is in the #8-12 weight range. You'll have a heck of a time compressing the denser balsa and it is "equal" to a properly compressed leather substrate. That is just my experience though.

 

[Rapt_up]

As Capid has said, there is balsa and balsa....

Balsa is actually a hardwood. The stuff in most hobby/modeling stores is the softest there is. Find some used in boat buidling cores...

Stitchawl,

You may want to look into trying #30-40 weight balsa. Most modeling balsa in hobby stores is in the #8-12 weight range. You'll have a heck of a time compressing the denser balsa and it is "equal" to a properly compressed leather substrate. That is just my experience though.

 

[HoosierQ]

Dude I know where you're at. Balsa is firmer as the blade is pulled edge training that a soft strop. Balsa is not going to compress and then curve back up rounding off the edge. Now a lot of strops hard and won't spring back like that. Balsa is a very soft wood for sure. What it's going to do over time is dent, and chip and break...the kind of stuff leather won't do.

Try both. I am really liking the feel of the edge trailing motion on my balsa strop, green compound. Provides some feedback "road feel" if you will. I have a homemade leather strop that I've been using. It is good but it's not flat. I am quite able to make a strop but I may just buy one to get nice even leather thinkness etc. I think the best strops from the old days were made of horse-hide which is very hard to get because of all the horse lovers for one and because nobody's eating horses so there's fewer hides to start with.

 

[Obsessed with Edges]

I'd characterize balsa as a 'different kind of soft'. It is easily prone to denting, such as from a fingernail or the blade edge pressed a little too firmly into it. But it's different from most common leather, in that it's not 'spongy', so it seems less prone to roll/form itself around an edge. It also gives a different kind of feedback; somewhat 'slicker' feeling than the grabby/grippy feeling of a leather strop. Depending purely on preference, that alone might be a good thing or not. And the one thing I noticed the most with balsa is, when used with compound, the compound seems much, much more aggressive on steel. Balsa strops load up with the black stuff from the blade very quickly. This is most of the reason why I'd consider balsa to be 'harder' or 'firmer' than leather, because of the way the compound seems to firmly embed in it, and really scrub steel from an edge.

 

[BluntCut MetalWorks]

Balsa grain is very long, while leather has short-weaved grain. Which corresponding to surface tension relief length (curling up), so ppl labeled balsa as a firmer substrate than leather because effectively it has lower/less edge convexing.

I've 1 hard balsa, the rest are cheap soft stuff (1/4 & 1/8 thickness) - all worked fine. I use 1/8" thick balsa as a disposable strop for polishing bevel.

 

[stitchawl]

Thanks for all the responses, guys. I think I'm seeing a very definite thread throughout the replies which is making me realize where my problem is with this balsa vs leather concept... I'll get to that in a minute.

Stitchawl,
You may want to look into trying #30-40 weight balsa. Most modeling balsa in hobby stores is in the #8-12 weight range. You'll have a heck of a time compressing the denser balsa and it is "equal" to a properly compressed leather substrate. That is just my experience though.

THAT would make a very big difference! I'll have to see if I can get some splits of that heavier weight balsa. But then... how would that differ from a softer wood such as basswood as a substrate? It seems as if both would have about the same 'spring' to them.

I think the best strops from the old days were made of horse-hide which is very hard to get because of all the horse lovers for one and because nobody's eating horses so there's fewer hides to start with.

Thanks. I'll have to look into the history of strop making...

I'd characterize balsa as a 'different kind of soft'. It is easily prone to denting, such as from a fingernail or the blade edge pressed a little too firmly into it. But it's different from most common leather, in that it's not 'spongy',

THERE!!!! It's that term 'spongy' that is spiking the soup! Strop leather shouldn't be spongy or soft. It should be hard! Really hard. Not the hardness of a cement floor but more like the hard resilience of an old oak kitchen floor. (Did that make any sense?!? LOL!) It doesn't dent when you kick your heels into it, but it doesn't tire out your legs when standing on it. Damn... I wish I had a piece of Horween's shell cordavan to send to you... You'd see the difference in the very first stroke. The most I can say is take a piece of 7-8oz veg tanned cowhide, wet it down, let it sit for an hour or two to dry a bit, then roll the hell out of it with a very heavy rolling pin for a half hour. Let it dry overnight and you'll 'begin' to get the idea of the firmness that good strop leather should have. Then imagine what a piece of Russian Red strop that was 'worked' for several days would feel like. No way in hell that the leather will curl over your edge (on a bench strop rather than hanging strop) unless you intentionally dig the edge in first.

And the one thing I noticed the most with balsa is, when used with compound, the compound seems much, much more aggressive on steel. Balsa strops load up with the black stuff from the blade very quickly.

That's an interesting point... If you're putting a layer of compound over the balsa, and we know that the blade is only contacting the compound, how does that softer substrate make it become more aggressive? Damn, I wish I had one of those CSI labs just to get some definitive answers rather than the subjective ones I come up with! Anecdotal evidence is fine for a Friday night, but not worth much come Monday morning...

This is most of the reason why I'd consider balsa to be 'harder' or 'firmer' than leather, because of the way the compound seems to firmly embed in it, and really scrub steel from an edge.

Now here's a thought... maybe the grit in the compound is able to dig in and 'stick up' rather than 'lay flat' because of the balsa, giving it a more aggressive advantage? I wonder what 'shape' the grit is? Does it have 'points' and 'edges' that make it work? Hmmmmm..... To 'me,' that would explain why the softer surface of the balsa could 'position' the grit to be more effective...

But... one thing is clear to me about the general use of leather for stropping. The leather is NOT being compressed first by most people, and hence the repeated references to the 'leather curling around the edge.' That just isn't going to happen with leather that has been compressed properly. To date, I've only seen two vendors (to knife sharpeners) who states that their leather has been properly processed. The rest spend more time talking about the fancy woods of the mounting paddles and the free compound that comes with it. "Pretty" is nice. "Effective" is nicer. And the only way leather is going to 'really effective' (that is to say, more effective than a compounded and hardened substrate,) is if it is properly processed.

The search goes on. The truth is out there...


Stitchawl

 

[Obsessed with Edges]

That's an interesting point... If you're putting a layer of compound over the balsa, and we know that the blade is only contacting the compound, how does that softer substrate make it become more aggressive? Damn, I wish I had one of those CSI labs just to get some definitive answers rather than the subjective ones I come up with! Anecdotal evidence is fine for a Friday night, but not worth much come Monday morning...

Now here's a thought... maybe the grit in the compound is able to dig in and 'stick up' rather than 'lay flat' because of the balsa, giving it a more aggressive advantage? I wonder what 'shape' the grit is? Does it have 'points' and 'edges' that make it work? Hmmmmm..... To 'me,' that would explain why the softer surface of the balsa could 'position' the grit to be more effective...

It was an eye-opener for me, in seeing how fast the balsa blackens up when used with compound. I also wondered what's so different about how the compound embeds into it; perhaps that's a big reason behind the popularity of using balsa, versus other materials, not to mention the sheer simplicity of making & using balsa strops.

BTW, I've tried diamond paste (1 mic), green compound and even Simichrome polish on balsa. They are all noticeably more aggressive, used this way, than when used on veg-tanned leather. Interestingly (and this hadn't really occurred to me until now), I also used the same above compounds applied to some printer paper, then wrapped over the very same balsa block. Not as aggressive as when used on the bare balsa alone. That's something to ponder about, and does seem to suggest something very unique & different about the embedding of the compound in the wood, versus how it embeds in the paper.

 

[capid1]

Hi Stitchawl,

I'm not sure if you are referencing me about the pretty wood strops w/ free compounds but I think I fall into that category Back when I first started making my own strops I read and read and read some more. I came across your post about "casing" the leather. I tried your method with the rolling pin a few times (even killed the handles from downward pressure). I didn't like the result or better yet the draw of the leather. It took away the feedback I need when stropping. I tried casing tooling, latigo, skirting, bridle and cordovan and none seemed improved in my honest opinion. I have a Walking Horse "horse butt" strop I bought to get a feel for a highly rated strop. It's boxed up as I can't stand the thing

Thanks for all the responses, guys. I think I'm seeing a very definite thread throughout the replies which is making me realize where my problem is with this balsa vs leather concept... I'll get to that in a minute.



THAT would make a very big difference! I'll have to see if I can get some splits of that heavier weight balsa. But then... how would that differ from a softer wood such as basswood as a substrate? It seems as if both would have about the same 'spring' to them.



Thanks. I'll have to look into the history of strop making...



THERE!!!! It's that term 'spongy' that is spiking the soup! Strop leather shouldn't be spongy or soft. It should be hard! Really hard. Not the hardness of a cement floor but more like the hard resilience of an old oak kitchen floor. (Did that make any sense?!? LOL!) It doesn't dent when you kick your heels into it, but it doesn't tire out your legs when standing on it. Damn... I wish I had a piece of Horween's shell cordavan to send to you... You'd see the difference in the very first stroke. The most I can say is take a piece of 7-8oz veg tanned cowhide, wet it down, let it sit for an hour or two to dry a bit, then roll the hell out of it with a very heavy rolling pin for a half hour. Let it dry overnight and you'll 'begin' to get the idea of the firmness that good strop leather should have. Then imagine what a piece of Russian Red strop that was 'worked' for several days would feel like. No way in hell that the leather will curl over your edge (on a bench strop rather than hanging strop) unless you intentionally dig the edge in first.



That's an interesting point... If you're putting a layer of compound over the balsa, and we know that the blade is only contacting the compound, how does that softer substrate make it become more aggressive? Damn, I wish I had one of those CSI labs just to get some definitive answers rather than the subjective ones I come up with! Anecdotal evidence is fine for a Friday night, but not worth much come Monday morning...



Now here's a thought... maybe the grit in the compound is able to dig in and 'stick up' rather than 'lay flat' because of the balsa, giving it a more aggressive advantage? I wonder what 'shape' the grit is? Does it have 'points' and 'edges' that make it work? Hmmmmm..... To 'me,' that would explain why the softer surface of the balsa could 'position' the grit to be more effective...

But... one thing is clear to me about the general use of leather for stropping. The leather is NOT being compressed first by most people, and hence the repeated references to the 'leather curling around the edge.' That just isn't going to happen with leather that has been compressed properly. To date, I've only seen two vendors (to knife sharpeners) who states that their leather has been properly processed. The rest spend more time talking about the fancy woods of the mounting paddles and the free compound that comes with it. "Pretty" is nice. "Effective" is nicer. And the only way leather is going to 'really effective' (that is to say, more effective than a compounded and hardened substrate,) is if it is properly processed.

The search goes on. The truth is out there...


Stitchawl

 

[stitchawl]

Hi Stitchawl,

I'm not sure if you are referencing me about the pretty wood strops w/ free compounds but I think I fall into that category

LOL! No... not thinking of anyone in particular, just remembering websites I've seen along the way, and some of the strops I've bought from them. I've seen some beautiful woodworking with an ordinary piece of $3 veg tanned leather glued on and sold for high prices. I'm sure that the folks who bought them were happy with what they got.

Back when I first started making my own strops I read and read and read some more. I came across your post about "casing" the leather. I tried your method with the rolling pin a few times (even killed the handles from downward pressure). I didn't like the result

Probably explains why there are eight or nine different choices in a horse race! We all have our own preferences.

I tried casing tooling, latigo, skirting, bridle and cordovan and none seemed improved in my honest opinion.

That's understandable... It's not possible to case latigo, bridal, nor cordovan. Latigo is alum and oil-treated, bridal leather is grease treated, and cordovan has already been compressed. I bought every different strop (unfortunately) that Hand American sold going back 15+ years. (Not to imply that they were in any way inferior, only that they didn't do what "I" wanted them to do.) As you said, latigo, black diamond leather, red diamond leather, bridle, tooling, etc., etc., etc.! Some with magnetic backs, others mounted on Corian blanks... Single sided, double sided... I think some of them are still hanging around the back recesses of my sharpening closet... Haven't bothered with them in years.

I have a Walking Horse "horse butt" strop I bought to get a feel for a highly rated strop. It's boxed up as I can't stand the thing

Now THAT is interesting... however, 'Walking Horse' does use butt leather rather than shell cordovan leather (both horsehide, of course,) and there is a difference, even if both are being produced by the "Horween Co." The butt leather doesn't get processed the same way that the shell cordavan does, which is similar to (but modernized) methodology of the old 'Russian Red Leather' hand process that was the standard for barber strops in the 1700's-1800's and into the very early 1900's. I'd love to hear your opinion after using a strop made from shell cordovan.

But sharpening and stropping are subjective, and we all have our own preferences. None are more right or wrong than any others. And we'll keep on experimenting with new and different ways to spend our evenings, be it horsehide, cowhide, MDF, Balsa, or stropping on the thighs of Virgins.


Stitchawl

 

[stitchawl]

Not as aggressive as when used on the bare balsa alone.

Does bare balsa (with no compound) give you any noticeable results? There are natural silicates found in all plant life so there should be some in balsa.


Stitchawl

 

[Obsessed with Edges]

Does bare balsa (with no compound) give you any noticeable results? There are natural silicates found in all plant life so there should be some in balsa.


Stitchawl

Assuming there are any silicates in balsa, I'm inclined to think it's not much. The wood by itself doesn't seem very abrasive at all (or, at least the balsa I'm using; the earlier comments about different weights/hardnesses of balsa have me somewhat intrigued).

 

[Obsessed with Edges]

(...) But sharpening and stropping are subjective, and we all have our own preferences. None are more right or wrong than any others. And we'll keep on experimenting with new and different ways to spend our evenings, be it horsehide, cowhide, MDF, Balsa, or stropping on the thighs of Virgins.


Stitchawl

:thumbup:
This is what continues to amaze me about stropping in particular. The more and more options I try, the more it seems there are likely an infinite number of ways to 'do it right'. As many have said, technique is really what matters, the vast majority of the time. A little applied creativity, along with a good grasp of the fundamentals of angle and pressure and understanding the steel and the abrasives, can yield great, sometimes even amazing results.

 

[tjiscooler]

I have two strops that were custom made for me. Red latigo. Horse leather. they are both for straight razors but the bench version I use on knives. the leather on them is very stiff. not very flexible, I know exactly what you are talking about! Its not like "regular" leather jacket leather or scraps you get locally, its like a whole new product.

 

[sqchram]

or stropping on the thighs of Virgins.

Hee hee