How To Use a Pasted Balsa Strop

[Tomo]

I thought I’d add a few photos of how I prep my strops. I do this once a month if it needs it or not.

1. First lap the strop to create a new clean surface. I now use the sandpaper on glass substrate shown above. 240 grit for the grunt work followed by 600 grit to refine the surface. I find it useful to frequently brush the balsa and sandpaper clean of sawdust. This keeps the paper from clogging which can create raised bumps of debris that scour the surface. A disused boar brush comes in handy for this. Full sheets are better than rolls, again the bigger surface resists clogging better than thin strips.

2. Now I cut some diamond paste with a little mineral oil on a ziplock bag. I mix it up into a smooth consistency with my fingers. This makes the oil based paste easier to spread evenly. It also breaks up any clumps that may exist in the paste.

3. Next I dot the surface all over with the mixture.

4. Then I spread out the dots with a synthetic bristle makeup brush for a flawless finish. A foundation brush is great for this purpose. It’s super soft and gets right into all the grain smoothing everything out nicely.

5. After a minute or so I gently wipe everything off with a soft cloth. You won’t get everything off but you want to get rid of any excess rolling around on the surface. If you hang onto the cloth they make an excellent polishing rag.

6. After a few hours I gentle rub the surface in with my fingers and again wipe the surface with a clean soft cloth. I think the strops come out pretty good.

The strops are bonded to a think piece of acrylic with two part epoxy. They are never coming off so you need to line them up well while gluing if you want your strop to look decent.

The current balsa is admittedly a bit thick and could be subject to uneven swelling. Thinner balsa is better but mine gets a bit thinner every month. It works really well.

 

[rbscebu]

Thanks @Tomo, a very good explanation. You have given me some ideas to try and improve my balsa strop pasting.

 

[rbscebu]

To solve the balsa alignment problem when glueing it to the substrate, I cut my balsa a little bigger (about 2mm to 3mm) all round. Once the glue is set (I use rubber glue), it's very easy to just sand the balsa down to size to match the substrate.

 

[Tomo]

To solve the balsa alignment problem when glueing it to the substrate, I cut my balsa a little bigger (about 2mm to 3mm) all round. Once the glue is set (I use rubber glue), it's very easy to just sand the balsa down to size to match the substrate.

I’ve got the hang of it now but it took a few go’s. I order the acrylic to the exact width of the stock balsa and one third of the length. Then I simply cut the balsa to length at home and get exactly three strops out of a length of balsa. 75x305mm is a great size. It should have been easy to line it up but I’m prone to a school boy error every now and again. Lesson learnt.

I like the epoxy because it’s incredibly strong, bonds well to smooth surfaces, goes off fairly quickly, cures crystal clear (which looks cool on acrylic) and doesn’t stay tacky when cured. Plus I already had some at hand so it was good to use it up. The only downside is that epoxy is a one time deal. Once it’s on it’s on for good. Unless you cut or sand the balsa off (which would be an option at the end I guess). At any rate I don’t think that I’m going to see the end of this balsa block for a few years yet.

There are probably a range of adhesives that are be suitable for this application so it’s good for people to hear which ones have worked well for others. Epoxy is expensive to buy, a hassle to mix, it’s probably overkill for the application but man-oh-man does it stick!

 

[kohalajohn]

I like the idea of a brush to spread the paste evenly, and a cloth to wipe away excess.

But do you have three brushes and cloths? Do you have a concern about cross contamination with the brush and cloth, the next month, containing particles of all three sizes?

 

[Slash McCoy]

Cloth can be an old tshirt. Throw it in the wash. Me, I don't use a brush... fingertips and the palm of the hand, both of which get washed now and then. Especially between grits.

 

[kohalajohn]

I like the idea of a brush to spread the paste evenly, and a cloth to wipe away excess.

But do you have three brushes and cloths? Do you have a concern about cross contamination with the brush and cloth, the next month, containing particles of all three sizes?

 

[rbscebu]

Of course it depends on how often you use them, but I find that I am relapping and pasting my balsa strops about every two to three months.

I SR shave daily and bring a new SR on line averaging about once per week.

 

[Biltong & Boerewors]

I thought I’d add a few photos of how I prep my strops. I do this once a month if it needs it or not.

1. First lap the strop to create a new clean surface. I now use the sandpaper on glass substrate shown above. 240 grit for the grunt work followed by 600 grit to refine the surface. I find it useful to frequently brush the balsa and sandpaper clean of sawdust. This keeps the paper from clogging which can create raised bumps of debris that scour the surface. A disused boar brush comes in handy for this. Full sheets are better than rolls, again the bigger surface resists clogging better than thin strips.
View attachment 1163328

2. Now I cut some diamond paste with a little mineral oil on a ziplock bag. I mix it up into a smooth consistency with my fingers. This makes the oil based paste easier to spread evenly. It also breaks up any clumps that may exist in the paste.
View attachment 1163331

3. Next I dot the surface all over with the mixture.
View attachment 1163332

4. Then I spread out the dots with a synthetic bristle makeup brush for a flawless finish. A foundation brush is great for this purpose. It’s super soft and gets right into all the grain smoothing everything out nicely.
View attachment 1163333

5. After a minute or so I gently wipe everything off with a soft cloth. You won’t get everything off but you want to get rid of any excess rolling around on the surface. If you hang onto the cloth they make an excellent polishing rag.
View attachment 1163334

6. After a few hours I gentle rub the surface in with my fingers and again wipe the surface with a clean soft cloth. I think the strops come out pretty good.
View attachment 1163335


The strops are bonded to a think piece of acrylic with two part epoxy. They are never coming off so you need to line them up well while gluing if you want your strop to look decent.

The current balsa is admittedly a bit thick and could be subject to uneven swelling. Thinner balsa is better but mine gets a bit thinner every month. It works really well.

Nice tutorial! German precision at work
Rightly or wrongly I believe that rubbing the paste with my hand with a fair amount of pressure embeds the particles into the wood, before I clean the excess of with a clean cloth.

 

[Tomo]

I like the idea of a brush to spread the paste evenly, and a cloth to wipe away excess.

But do you have three brushes and cloths? Do you have a concern about cross contamination with the brush and cloth, the next month, containing particles of all three sizes?

The 0.1u strop sees 99.9% of the action for me. I only use the 0.25u and 0.5u strops when setting up a new razor which is rarely. I just use my fingers and a T-shirt rag on the rare occasion that I refinish those strops. It works almost as well.

I lavish a bit more attention on the 0.1u which sees daily action and monthly lapping. You are allowed to contaminate course grits with fine ones but not the other way round. Once you use sandpaper, brush or cloth on a course diamond grit it is spoiled for use anything finer.

By the end of the month my 0.1u strop darkens with swarf and I notice a slight drop in performance. Balsa is very soft so regular lapping can’t hurt to keep it flat. Others get away with less but monthly works for me. I’m also trying to get my balsa thickness down.

 

[rbscebu]

I have three balsa strops, one each for 0.5um, 0.25um and 0.1um. The 0.1um gets the most work as it is used daily after each shave. Because of this I decided to make a fourth balsa strop, just for post-shave maintenance.

This morning I started finishing off my fourth balsa strop. Suitable acrylic is not readily available for me so I made this strop out of composite materials.

​

Top layer is 8mm thick balsawood. This is glued to part of a 6mm thick smooth ceramic tile (middle) using rubber glue. The bottom layer is 20mm thick PVC closed-cell foam (blue), glued to the underside of the tile using structural epoxy glue.

The tile was cut to size (300mm x 75mm). The balsa and foam were each cut to about 305mm x 80mm before glueing everything together. Once the glue had set, it was only a matter of sanding the balsa and foam (easy) down to the size of the tile.

Now all I have to do is give the foam surfaces three coats of acrylic paint, lap the balsa flat and apply the 0.1um diamond paste.

The finished balsa strop has a mass of 324g (S.G. = 0.45). That makes it about half the mass of a balsa strop with acrylic substrate, thus being even better when used as a hanging balsa strop.

Total material cost was under USD 6 but it took some time and effort to make. Acrylic substrate would have been easier to make.

 

[kohalajohn]

Nicely done.

I also made a fourth balsa, being my daily .1u


Sent from my iPhone using Tapatalk

 

[kohalajohn]

RB,

Like you, I realized that the .1u was doing all the work, so I made another.

But then I came across another reason. I tried a variation of The Method. I don't use the balsa at all, during the week. Then on Saturday morning I catch up. Now, just using the 1.u would take forever, and that's why we use the .1u after every shave.

But what I do is strop on the .5u, .25u and 1.u progression on Saturday morning. fifty laps on each.

That seems to bring it back fine.

Then Saturday to the next Friday I just strop on leather and shave.

I could probably go longer without the balsa. As we know, a SR can go for months between honing. but then it would take an annoying long time to bring it back. I'd likely have to start with a nani12 or even coarser. The Saturday way seems to work ok so far.

 

[Tomo]

I’d like to retract my previous comment about epoxy. After making a few more strops, I believe that spray contact adhesive is the way to go in line with the previous advise.

The trouble with epoxy is that it is prone to large bubbles that don’t bond. It also likes to slip around until it sets. Sometimes it works really well, sometimes not so well.

A contact spray adhesive goes down evenly and gives a flawless finish right to the edge of the stop with no bubbles. It’s designed for use on large flat surfaces. See below. The top strop was prepared with spray adhesive the bottom two are epoxy.

 

[Tomo]

For my latest set of strops I’ve tried to follow the instructions exactly. 0.25” balsa glued to 0.75” acrylic with Selley’s Kwik Fix spray contact adhesive. Clamped two strops overnight as glue set with balsa side in and acrylic side out. Lapped with a 180-360-600 sandpaper progression glued to a granite surface plate. These are my best strops yet. Lesson learnt. Follow the instructions exactly.

 

[rbscebu]

RB,

Like you, I realized that the .1u was doing all the work, so I made another.

But then I came across another reason. I tried a variation of The Method. I don't use the balsa at all, during the week. Then on Saturday morning I catch up. Now, just using the 1.u would take forever, and that's why we use the .1u after every shave.

But what I do is strop on the .5u, .25u and 1.u progression on Saturday morning. fifty laps on each.

That seems to bring it back fine.

Then Saturday to the next Friday I just strop on leather and shave.

I could probably go longer without the balsa. As we know, a SR can go for months between honing. but then it would take an annoying long time to bring it back. I'd likely have to start with a nani12 or even coarser. The Saturday way seems to work ok so far.

That is were a matching seven-day set comes into play. It's like using the same SR all week but you only need to 0.1um balsa strop all seven once a week.

Besides, it looks and feels good to have a M7DS .

 

[rbscebu]

.... Lesson learnt. Follow the instructions exactly.
....

You're a slow learner but you do learn.

 

[Slash McCoy]

@Tomo well done. Maybe you will inspire others to stay on the path of righteous honing, and not stray astray. We kinda got this all worked out. If there was something amiss in the method, we would have found it and corrected it by now. Good Shewwww!!!!!!!!

 

[Tomo]

You're a slow learner but you do learn.

That’s the difference between me and you @rbscebu. It’s about time that you got on board with the acrylic. It’s the way to go. Heaps better than foam and tiles. Give it a try. I think you will be pleasantly surprised.

 

[kohalajohn]

That is were a matching seven-day set comes into play. It's like using the same SR all week but you only need to 0.1um balsa strop all seven once a week.

Besides, it looks and feels good to have a M7DS .

What set do you have? I don't have a set yet, but have always been interested