Fixing Finish Problems

You can get 0000 stainless steel wool which has the advantage of not embedding rusting threads of metal in your finish. I’ve seen furniture restoration specialists use it on french polished surfaces to prep them for spot repairs.

The non ferrous ones contain nickel and won’t stick to your pickups either.

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You can also use FFF grade pumice (FFF dental pumice or FFF indutrial abrasive pumice). While it would be a pain in the cunning linguals to use to wear down an existing finish, it’s great for prepping a porous wood surface for finishing. You dust it onto the wood and then use soft cloths to rub shellac or thin varnish into the wood. The shellac soaks into the wood, raises loose fibersand the pumice grinds them away (like wet sanding). When the shellac sets, it seals pores in the wood with the pumice and ground own wood fibres leaving a smooth surface with very visible grain. I used this on a refinished cigar box for a friend, except I used fine diatomaceous earth and not pumice (It’s what I had, though pumice is better).

Here is a great example of how to do this. Mark is a retired Aussie shop teacher who makes absolutely wonderful stuff on the ThouPipe. Here, he’s finishing the chassis of a wooden clock.

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Oh that’s interesting.

I have never thought to use this on wood but for very fine knife and razor honing there’s a method used with natural sharpening stones, where you rub two of them together while wet to form a slurry of very fine abrasive suspension. It’s in the 8000-10000 grit range. I wonder how well that would work on finished wood.

The technique developed independently in Europe and Japan so it’s pretty much an old worldwide thing; my guess is someone would have tried this on other stuff by now, so it probably doesn’t work well.

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This process is called lapping and is how you keep your stones flat.

Something along the same lines would be automotive rubbing compound.
Works great for restoring car headlight lenses.
I wonder if anyone has tried that on a guitar finish? :thinking:

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I have , on a pink squier strat that had fine sand paper scuff marks in the thick poly finish after a dodgy relic job it took them right out and left a satin finish that felt like nitro I used t cut original formula

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Can you please explain what you mean by this?

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Brad Angove uses cutting compounds (basically a colloidal suspension of very fine grit) to polish guitars. That’s pretty much the same thing. He’s got an amazing channel about building “gitters” and finishing them.

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No, this is very, very different from lapping. I’m familiar with lapping.

The european version of this involves belgian stones called Coticules. You use the base stone to hone on, and the small companion stone to raise the slurry on the base stone.

Here’s an example where he has raised the slurry on the main stone with the smaller companion stone and is honing the knife in the slurry (the white fluid on top of the yellow stone):

image

process described here:

With Japanese sharpening stones, it’s different. There’s a whole progression of finer and finer companion stones, called nagura, with a final companion stone made of the same composition as the main stone, called a tomonagura.

They aren’t used for lapping, but to raise the fine slurry to sharpen in.

I’ve owned both, both are great for results on knives; razors work better with the Japanese stones.

And that’s your advanced knife honing technique trivia for the day :slight_smile:

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I misunderstood what you were saying.
So he is only using one stone to raise a slurry to sharpen a knife, chisel etc.
This is a smart idea and should cut down on the number of times you need to lap stones.
Thank you for the clarification.

Next we’ll cover the Scary Sharp system :joy:

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Yeah. With Japanese stones it’s a little different; the base stone is usually ridiculously hard and the nagura are softer, so the slurry is like 80%/20% from the nagura. So you use progressively finer nagura - there are four main types - until the last stage, where you use a stone similar to (or ideally, a fragment of) the base stone to raise the slurry, which is then 100% super fine particles from the base, which end up >= 10k grit or so.

Works great. Edges like mirrors. Time consuming but nothing else comes close.

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I use a similar Canadian process in my carpentry finish work @howard. I use the knife until it’s dull and then I snap off the blade and use the next sharp portion :wink:
olfl-2_1

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Yeah! The American way too! I still do that for everything but the kitchen knives, lol.

I quit shaving with straight razors after a couple years. Was a fun diversion, and kind of macho-cool and anachronistic, but a big hassle. Sold all my honing stuff except for one Shapton 1k grit I kept for the kitchen.

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I do hand sharpen all my finishing chisels. I use a Lee Valley jig as a honing guide to set the right bevel angle.
I actually find it relaxing as odd as that may seem to some.
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https://www.leevalley.com/en-ca/shop/tools/sets/102435-cabinetmakers-sharpening-sets-with-mk-ii-honing-guide-stone?item=05D0503

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I totally get it. It is relaxing. That was the main reason I did it, actually.

Plus you end up with nice sharp stuff.

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And plane blades.
I use box cutters to cut up boxes, as the name implies, :slightly_smiling_face:although I have used them for dovetail layout work.

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This is one thing I admire about Japan. You can do one thing, do it well, and will be respected for it. Doesn’t matter if you’re a cook or the guy who sharpens blades.

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So, @JustTim, when do we get to see some pictures?

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Yep, my Shapton 2k is the one that lives under my kitchen sink.

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I use Olfa knives for EVERYTHING. They’re great for scribing (metals, plastics, woods), rough dovetailing, installing door hardware, trimming, etc. etc. I have three, and they’re absolutely essential.

I learned all the benefits of these things when I worked construction installing highrise windows.

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What also works is tooth paste. Most toothpaste has very fine abrasive stuff in it which works great for polishing.
I used it once to give a painting job on a guitar the last bit of polish. Another advantage of this: The guitar smells minty afterwards.

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