The OTHER kind of planer----sharpening DW675 carbide blade inserts

I was planing some wood the other day (surprised?) and it felt too much like work. How sharp are these blades, anyway? It turns out, not very. The DeWalt DW675 3-1/4" planner uses a double sided solid carbide blade, and while I seem to remember flipping them a few years back, there has been a lot of harsh use since then.

Carbide inserts are great! Long lasting and, at least if you have some diamond hones, easy to sharpen. REALLY easy compared to HSS or D2 tool steel, and since carbide won't get all that sharp ANYWAY..... you don't have to feel like a slacker for only going up to a #600 grit or so. Yes, I actually sharpen disposable inserts. In less time than it takes to go to the store and back, I can hone the inserts to good-as-new sharpness. The store doesn't have these inserts anyway...... this is WAY faster than waiting for Amazon.

Old/new

2 blades 180 degrees apart, 3 gib screws per.

 I just used the skinny little wrench that comes with the planer. I think that it's a 10mm. I guess this would be lefty-loosey (that saying still doesn't make sense). My hone is a double sided Smith's diamond hone from the Walmart fishing department. I think that I paid $7.95 about 10 years ago and the damn thing still works fine. Not very precise, but good for this type of thing.

I do one blade at a time.

The retainer is a 2 piece arrangement with  the carbide blade sandwiched in between. There are registration grooves that ensure proper alignment, and it seems like a practical design. Simple, but effective. There are also 2 set screws to adjust the height. I just leave those alone, as we're only removing the tiiiiiniest amount of metal, not trying to grind out big chips.

This is the carbide insert, bevel side up, right at the edge of the workbench. Right behind that is a piece of plywood that I use to hold the blade down. The plywood is also beveled, but that is just to give clearance, NOT to act as some kind of jig. This is WAY to easy to need a jig, just squint and free-hand it. 

Here is the blade, clamped down and already honed. It is sticking out maybe 2mm, just enough to work on. The hone is a coarse (#240 'ish?) and fine (#600?). I do both.

Don't forget to hone the back, too. Then put it back together.

When I reset the blade, I let the insert protrude just the smallest amount, about 1/64.

That's it. Maybe 15 minutes to do both inserts, all 4 edges. Really.

We are surrounded by soooo much discarded waste, much of it originally bought out of "convenience". Being able to maintain and actually improve your tools, make them as sharp as you could wish for, learn how to actually DO something..... That make the concept of "convenience" laughable. If I were to give one piece of advice to a woodworker, it would be "Learn how to sharpen your tools". Dull sucks.


Now....... Time to tune up the Japanese plane....

Diamonds are a carpenter's best friend

Looking at those horrible photos of my unfinished workbench kinda reminded me that I had intended to actually build some drawers for the thing. Which means that I've got a lot of stock to machine up (I am in no way a hand tool purist) , but before that happens, I've got a secret to tell. I have never replaced the planer blades in my old Delta planer.

Good old Blue/Gray

And it shows, big time. Just like not washing the car until it turns green, I was able to put off buying new knives and enduring minor tear-out, for a long time. Then I bought a bunch of Port Orford Cedar (POC). This wood is beautiful and when perfectly planed, leaves a shimmering almost iridescent surface.

Port Orford beauty

This is from Merriam-Webster;

cha·toy·ant

adjective \shə-ˈtȯi-ənt\

Definition of CHATOYANT

: having a changeable luster or color with an undulating narrow band of white light <a chatoyant gem>

Origin of CHATOYANT

French, from present participle of chatoyer to shine like a cat's eyes

First Known Use: 1816

REALLY nice stuff, but rather prone to tear-out when planing. Old Blue/Gray could still handle mahogany (amazingly well after 20 years and possibly 1000ft linear with only minor honing) with no problem, but POC? No way. So this last winter, I took a few days and sharpened (hahahahah) the knives with very underwhelming results. Made a jig and and burned through about $10 in wet/dry paper and maybe ever made them more dull. Hard to tell.

So what's different this time? First of all, someone's watching (you) and secondly, I bought some diamond stones.

cheap

The first set is a cheap three set no name import special that I got at a local store for $7.95, but you can get them from Amazon for around $12 (2013) delivered. Oh yeah, 2x6 inches and slightly bowed along their length, very flat in width. Those little dot looking spots are actually holes in the metal plate that allow lubrication fluid and metal swarf to get out of the way.  The colored part is thin plastic. Not so good for chisels or things with pointy parts or small surfaces, though. All and all, they are rather durable, very aggressive at 150, 300 and 400 grits and I use them for lots of different things that would ruin my real stones.

Hold it!

Mount them on some blocks of wood and they flatten right out. Use a good quality spray adhesive like 3M super 77 (16 oz for $10-12) or 90(16 oz for $18). Kinda spendy for glue in a can, but you'll find plenty of uses for it. I can't find a good price with free shipping, so check locally. If you intend to use these stones for precision work like this (hahaha) you might want to check them for uniform thickness along their length and adjust accordingly. I am going to re-do this set, they work that good. A bargain at twice the price.

Not as cheap

The second is an 8" DMT Duosharp that I got off Ebay for about $50. It is  a Fine/Extra-fine 600/1200, is also slightly bowed along it's length and flat in width. These little dots are hard plastic that is flush with the diamond coated surface. Still not too great for chisels, though. Really nice when you knock down the high spots (all diamond stones need to be broken in a bit), this stone is a lot more refined than the others. Heavy and stiff means that there is no easy way to flatten it and honestly, if I was paying retail, I would return it to see if the second one that they sent was REALLY as flat as they say it should be. As it was, it was a close decision as to whether or not I should just re-sell the thing, but after I used it for a bit, it grew on me. I guess that I like it well enough to consider spending  $100 on a diamond coated sliver of metal taped to a piece of aluminum (Tsuboman Atoma diamond flattening plate) , so make of it what you will. I hope that Amazon decides to carry them soon. I would love to try one out. One thing is certain, though. I will NEVER go back to wet/dry paper, I'll tell you that.

OK, reference surface.

Birchwood-Casey Perma-Blue gel takes about 1 minute to apply and turns the metal black which gives you a good reference surface that tells you when you've missed a spot.

You're an adult, make your own choices

In the this photo, you can see the tripod stand that I made for planer knives. It's just a block of wood with a tight fitting slot that the blade slips into, attached to a stick about 10" long or so.

Fancy, no? No.

In use

So as you can see, the jig merely holds the blade at a more or less constant angle that is adjusted by using a variety of spacers underneath the leg. Trial and error, with a bit of measurement, will get you what you need. I would lean more heavily towards the measurement side. You may also notice that the DMT stone sits on a piece of $store shelf liner, which is on a piece of 1/4" float glass, which also sits on more shelf liner. Now that I think about it, there is no reason for the glass really, is there. It must be some sort of permanent muscle memory kind of thing left over from my "Scary Sharp" days. And in case you were wondering, yes the liner material keeps things from sliding around, yes it does introduce slop and contributes towards inaccuracy, and no I am not missing the first joint of my thumb (yet). You can also see a couple of pieces of slate in the background that I use for polishing up the finished edge.

I'll write up a new and improved version one of these days, but for now this is pretty ghetto, but it works. Or you could just buy new ones. Knives, that is. Or a new planer, I suppose.

Photo intentionally blurred to hide scratches. Actually my camera hates me.