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How To Use a Pasted Balsa Strop

rbscebu

Girls call me Makaluod
There’s a couple of model shops around so I’ll give those a try
Most modelers are looking for low mass balsa. We balsa "stroppers" should be looking for relatively clear straight-grained balsa, not necessarily low mass.

(For the old(er) man @Slash McCoy, "mass" for you can be considered "weight".)
 
I had to give up looking local. If I wanted some thicker pieces (3/4 or 1 inch thick) and 3 inch wide doesn't seem available. Craft stores has 3/4 and 1 inch square... but nothing 3 inches wide and thicker than about 1/4 inch. The couple hobby stores I called didn't have any thick sheets either.
 

Slash McCoy

I freehand dog rockets
I had to give up looking local. If I wanted some thicker pieces (3/4 or 1 inch thick) and 3 inch wide doesn't seem available. Craft stores has 3/4 and 1 inch square... but nothing 3 inches wide and thicker than about 1/4 inch. The couple hobby stores I called didn't have any thick sheets either.
1/4" thick is perfect. If it is thicker, then when it swells it can do so more unevenly. Staying thin keeps it under control. You mount the thin balsa on thick acrylic before lapping. The thick acrylic resists warping and flexing, and makes it easier to hold it in hand, which is superior to just flopping it down on your workbench and trying to over-control the razor with two hands. Anyway, you glue the balsa to the acrylic, then lap it, then apply the paste, then wipe the paste off so that the only abrasive on the balsa is embedded, and not rolling around on the surface. That is how you get the crazy sharp edge. If you don't want it that sharp, then just stopping at the 12k stone or 1u film is sufficient and the balsa is not needed.
 
I can get Jende Industries Poly Diamond Emulsion and their Nanocloth Ultra Strop-blok is this something I could use insteed of the balsa and is this Diamond good to use? Anyone tried it?
 

rbscebu

Girls call me Makaluod
I can get Jende Industries Poly Diamond Emulsion and their Nanocloth Ultra Strop-blok is this something I could use insteed of the balsa and is this Diamond good to use? Anyone tried it?
No substitute for balsa. Know nothing about diamond emulsion. Where is your location?
 

rbscebu

Girls call me Makaluod
I live in the Netherlands there is a website which sells these products over here
If you are having trouble sourcing balsa, try different hobby shops or on-line. You can also get balsa on AliExpress although delivery may take some time.

For diamond paste, I bought mine on Amazon in the US and had it shipped to the Philippines. With shipping it wasn't cheap at about USD 60 total for 3 x 5g tubes, one each 0.5um, 0.25um and 0.1um. Fortunately that should last me for well over 5 years.
 

Slash McCoy

I freehand dog rockets
I can get Jende Industries Poly Diamond Emulsion and their Nanocloth Ultra Strop-blok is this something I could use insteed of the balsa and is this Diamond good to use? Anyone tried it?
You can use anything you want. If you want balsa results, use balsa. If you want diamond paste results, use diamond paste. To follow The Method, you must follow The Method. Use the way that has proven itself to be easy for a beginner to use, and that has been proven to give best possible results, and that has been proven to be cost effective, is my advice. If you do not pay close attention to the details, you will fail. You may achieve a "good" edge but you will not know the sharpness of the Method edge. If you omit things that you think are unimportant, or make substitutions or additions, you are outside the method. Coloring outside the lines. You may congratulate yourself on your creativity and resourcefulness but you will not achieve honing Nirvana. If you read this thread you will see that this is a central theme. Guys ask if this or that will work. This is the wrong thread for them. Some are destined to wander in the desert for 40 years. Some are lead up the path and up the mountain. Some never cross into the promised land at all. This is the mountain. This is the stone tablets and the burning bush. "I is what I is", sez The Method.

Specifically, nanocloth was all the rage a few years ago. Among the membership here, it has gone the way of Clackers, the Hula Hoop, and Pet Rocks.

If you like to change things or improvise or experiment, cool. But be sure you have plenty of water for your sojourn in the desert. Such creativity is best left for after you master The Method.
 
At first, one is attracted to micro cloth instead of balsa, because you avoid having to lap the balsa every few or several months.

But the lapping is actually one of the advantages of balsa. Any paste medium eventually becomes clogged. When that happens with balsa, you can make it new again.

BTW trying innovations is ok. For example I have started using a sheet of 60. Faster. Do the .1 then the .25 then the .5, in that order. Then on a finer sheet, 400 or so. Also starting from .1. Then either toss the sheets or put them back in the tool shed for general use, as you can't use them for lapping balsa again.
 
Having gone into some detail when asked or prompted in many threads, I thought I should comprehensively lay out the method in a separate thread, for reference.

Thing 1. The Balsa Strop.

Buy 3" wide balsa. Best to buy a 36" length. It is cheaper. Hobby Hut, Hobby Lobby, and other brick and mortars carries it. Or purchase online, at 3x the cost. 1/2" thick works well. Cut it into 3 12" pieces. For best results, which I believe are the only results worth pursuing, glue the balsa to a heavy piece of glass, or marble tile cut to size. Not wood. Not plastic. The idea is to bond the balsa to a dimensionally stable substrate, to fight the tendency of the balsa to warp.

The balsa must be lapped, for best results, which as I already pointed out, are the only type of results worth pursuing. Even if it looks flat and smooth. try 220 or 320 grit sandpaper. Or 400. Whatevah. Or a progression. Spray the back side of the sandpaper with Loctite or 3M spray adhesive. Just a faint dusting of the adhesive works great. Carefully stick the sandpaper to a polished granite countertop or a large heavy piece of glass. The flatter, the better. Eyeball flat is not good enough. Make sure the sandpaper goes on smooth and tight with no bubbles or wrinkles. This is extremely important. Now place the balsa face down on the sandpaper and carefully rub rub rub. When you see you have created a whole new surface, obviously the balsa is now as flat as the sandpaper. So, the flatter, the better.

Thing 2. The Diamond Paste.

I have not experimented much yet with finer grits than .1u, so that is the finest I can authoritively comment on. You need .1u, and .25u, and .5u. If you made 3 pieces, that works out well. I get mine from www.tedpella.com but there are a lot of vendors. It is sold in as high as 50% diamond but there is no need to go over 10%. The reason is, less is more. You want the diamond crystals embedded into the balsa, not rolling and scooting around on top of it. You can also get 1u and 3u, both of which are handy for polishing even if you dont use them on balsa much or at all.

Thing 3. Putting it all together.

It only takes a little bit. If you think you got enough, then you probably have about 3x too much. You MUST NOT have a coating on the balsa. You want a very small amount, rubbed in to the balsa. About 1/3 of a pinto bean worth or a bit less. Spread it around and rub it in good. You can thin it down with acetone or something if you like, for better distribution. Now, this is very important. It doesn't matter if you contaminate a coarse grit with a finer one. But you must NEVER let a coarser grit contaminate a finer one. the way it works is each stage makes scratches in the steel, the size of which is determined by the grit size. Each grit must totally eliminate the coarser scratches of the previous grit, replacing it with its own finer scratches. Even a few crystals of a coarser grit basically ruin your results from the finer grit. So, always clean your hands thoroughly when going from grit to grit. Applying diamond to the balsa, start with the finer grit first. Label it by writing the grit size on the ends of the balsa. Do the .1u balsa, then the .25u balsa, then the .5u balsa, etc. Now the proper sign is μ which stands for micron, but we usually use "u" because it is right there on the keyboard.

Thing 4. Using it.

You COULD just use the balsa to touch up an edge that is failing, but I prefer to hit it after every shave, so I never experience a dull or dulling edge. At least, not often. I go 2 or 3 dozen laps on the .25u, then a like number on the .1u. Fairly light pressure. Edge trailing. Use a slight x stroke even though the balsa is wider than the razor's edge. Always wipe the blade VERY WELL after stropping on a pasted balsa or between grits. You MUST NOT contaminate the finer balsa with coarser diamond, or get any diamond on your regular leather hanging strop. You will NOT GET BEST RESULTS if that happens. And best results are the only results worth pursuing. Sometimes I skip the .25u and just go 4 dozen laps on the .1u. I finish by laying the blade on the balsa and drawing it straight across and off the balsa. This helps to remove any fin edge. Occasionally it will seem like my edge is starting to go north on me, and that is when I go with the .5u or 1u. I strop until I am satisfied with the way the razor treetops forearm hair, then I hit my finer grits as usual.

Thing 5. Improving it.

After final stropping on diamond/balsa, I like to give my razor a special treat. I keep a piece of 1/16" thick, 3"wide balsa unpasted. I rest one end on a bench or counter or table, and hold the other end in my left hand. I strop on this very flexible unpasted balsa sheet, letting it sag slightly, about like a hanging strop drawn moderately tight. This seems to remove any vestiges of fin edge much better than linen. I am still experimenting with this technique but it is definitely an improvement.

Thing 5. Maintaining it.

After a few weeks, you may find that the balsa needs a refresh of diamond. You could just add a bit more, about half of what you used when you first pasted the balsa, but for BEST POSSIBLE results, which are the only kind of results worth pursuing, go ahead and re-lap the balsa. Sure, you got it flat, but it isn't flat anymore. Flatter is better.

Thing 6.. Other abrasives.

I have been asked again and again if CrOx (Chromium Oxide) won't work. Yes, it does work. I just don't believe it works as well as diamond. First of all there is basically only one grade of CrOx. Call it .5u, or call it .3u. The particle variation is so wide that it is practically the same whichever way you call it. If you use CrOx and you want to go finer, get some FeOx, or Iron Oxide, which runs around .1u grit size. Yes, they are cheaper than diamond. But you use so little, the cost is irrelevant. I strongly recommend going with diamond. Best possible results, right? You might also take a look at CBN, Cubic Nitride Boron or something like that. The new thing.

IN CLOSING, I just want to say that this works. I basically never have to re-hone a razor that I have maintained with this method. YMMV, I am sure, but there is no reason not to try it my way. Hardly any steel is lost even in daily use. 1u is approximately equivelant to a 12k Naniwa Superstone. .1u of course is 10x finer. Some naysayers will state that this will surely cause a harsh edge. I use this method and the only kind of edges I get are sh-sh-sh-sh-SHARRRRRRRPPPPPPPP ones. Give it a go, and if you do it right you will love it.
Can I use basswood instead of balsa? Is there a difference between two? I checked our local michaels all they have is basswood.
 
The gents here have tried all sorts of different wood, and the consensus seems to be that balsa is best.

You will be able to find it. Hobby shops, amazon.
 
The gents here have tried all sorts of different wood, and the consensus seems to be that balsa is best.

You will be able to find it. Hobby shops, amazon.
Understood. I pasted suede blocks for my knives. Is balsa more appropriate for razors?
 

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Found some! I saw on your YouTube video you suggested holding up the strop block flat. Wouldn’t be better to shape this into something like a paddle strop? It’d be easier to hold. Also does 0.25 thick need backing? Can I use the whole piece as a strop and not cutting it?
 

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Yes, you need to use an acrylic plate as backing. Write each grit size on the side of the balsa that you are going to glue to the balsa. Then you can read which one is which, through the transparent acrylic. Use spray adhesive.

No need to shape it into the handle shape of a paddle strop. A rectangular 12x3 shape will feel fine in your hand.

Personally I would trim the 4 inch width down to 3 inches. Unless you have huge hands, 3 inches is more comfortable.

Trimming balsa is easy though. An exacto knife to create a deep cut, and then you can snap it over the edge of a bench.
 
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