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Hey guys,

I would appreciate your tips on getting chisel edges to last in spruce - especially paring end grain spruce - for example shaving/fitting brace ends...

For as "soft" as spruce seems - paring end grain spruce sure eats chisel edges... It is tearing up my chisel edges in ways that cherry, maple, and oak just don't do....

This seems to be a duty which requires contradictions.... Spruce end grain needs a super keen, sharp edge to cut - yet that super keen edge wants to roll or chip... Which would point to perhaps a microbevel - which has a higher angle that doesn't want to cut as readily because of the long fibers...

What are you guys doing here for chisel edges? Is there some particular chisel which seems to do this duty better than others?

My fave is a japan woodworker #2 thin gouge it/s a short blade with a long wood (ho) handle buffed out it is super sharp, I reground some old usa chisels to abt a 20 deg bevel and they are super sharp for creating a knife edge on the top bracing and carving braces down at the ends, Furthermore I have 2, double bevel number 1 carving chisels swiss made one is 1 in wide and 46 yrs old the other 3/4in one is 10 yrs old. I reground these carving chisels to a 15 deg bevel and buffed them out with jewellers rouge .They are also excellent for carving spruce . cedar . fir etc.

Rolling is too soft and chipping too hard? I like and use the Veritas PVM-ll for my bench chisels and a couple lovely Blue Spruce paring chisels for carving spruce bracing, no issues with either. The Veritas have the edge, on holding an edge

Hmmm... I’ve never worked with cherry or oak. Not much end grain carving except on Spanish cedar heels. I don’t seem to have much issues with spruce endgrain. I use a blue steel Japanese chisel (koyamaichi) ground to a 30 degree angle, which seems to be a nice compromise between finesse and edge retention. Works for me.

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one day I was sharpening chisels I was using for mortising face pulls so that they were very slightly proud of pocket doors...problem was that the doors were laminate over engineered plywood...e.g. the chisels were taking a heavy beating on every door and I found it necessary to have multiple available to last a day's work...

during this sharpening session I had a sort of epiphany...I correlated how Katanas are so deadly with the procedure I was doing...Katanas (samurai swords) have a convex edge (the opposite of hollow ground) which along with their curved bodies make them a deadly slicing instrument...

that aside, what came into my mind was using a double micro bevel for durability of the edge (kind of simulating the convex edges of Katanas)...I sharpen my chisels using a WorkSharp 3000 with a primary bevel of 25*...micro bevel was at 30*...the addition of a tertiary bevel at 35* made the edges last at least 2x as long.

admittedly my use of this procedure is oriented more towards abuse of an edge, but I've found that the edge also lasts much longer under general use also...

as with all concepts YMMV

edited to reflect correct terminology as Chris Pile pointed ouit

Since when is concave the opposite of hollow ground? I used to grind a hollow ground concavity in the cutting edge of end mills, etc. when sharpening tools back in my tool & die shop days.

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"Act your age, not your shoe size" - Prince

rmmmm....since:

1: I'm being an idiot
2: wife has stage 3a breast cancer Her2+
3: took her to chemo today and had my alternator fry in the process and thankfully made it there and back
4: was taking a slight break before I went out and replaced the thing

e.g. I'm rather distracted right now...but hey, thanks (no sarcasm) for pointing out my error in terms...

convex is the right term (as I described it per sharpening technique), neh?

All the best wishes for you AND her!

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"Act your age, not your shoe size" - Prince

+1

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Keep in mind that newer steel is just what it used to be. I use quite a few Stanley everlasting chisels from the 20's and 30's and these just keep an edge like forever. I've used a bunch of newer style chisels and that just don't hold an edge for the long term.

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I visited a renowned luthier's shop a few months ago--he was busy sharpening his chisels when I arrived--close to two dozen Stanley's. He said that he owns all kinds including super expensive ones, but cheap and lots of them seemed to fit the bill for him. Happened to be batching nearly 30 guitars at that time.

Not all steel is the same. The heat treat process is very important. If not done well your chisel is just pretty metal. I have many chisels all good steel. Few cheap chisels are worth picking up. A good tool is an investment cheap tools a cost.

Learning to sharpen is also key , how you send that edge and grind can make or break a good chisel.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

You are right end grain spruce does eat chisels. As people have said some steels are better than others but it is still an issue. A slightly higher honing angle can help but if you go too far they won't cut very well.

I do two things, as someone above said I have a number of chisels of similar sizes so can swap to a new one as one goes blunt. I then do mass sharpening sessions. The other thing is I try to do the shaping of the brace ends off the guitar before glueing, using a bobbin sander. Getting reasonably close and leaving just the last bit to do with a chisel makes life easier. It also reduces the chance of damage - I really don't like waving sharp chisels round my soundboard!

Dave

Somebody needs to invent a chisel sharpener that works like those automatic pencil sharpeners where you stick the tip in, wait a second, and it comes out sharp.

Dave thanks for the tip . I usually carve braces in situ. i will try your method .Here we call a bobbin sander a spindle sander in the usa

I sure would love to try out some better chisels... I really want to give the PM-V11 chisels a go... So far - the ones that hold up the best are Woodcraft green handle 52100 alloy import chisels and my rehardened Buck Brothers chisels... Aldi chisels, new production Buck Brothers, current production Stanley hardware store chisels are next. The Aldi chisels were a surprise for how well they seem to hold up... Dead last is my new Pfeil chisel - which is a huge disappointment for the price I paid. It is all but useless because it is too soft.

Sounds like perhaps the next thing for me to try is a very slight micro bevel.... And send the Pfeil chisel back because something is wrong with it.

I think the Work Sharp 3000 is probably as close as you can realistically get to that level of convenience. I probably lose all street cred (like I had any) for not sticking with oil or water stones, but I need something that works fast and tolerates fumbling hacks like me.

Get lots of extra glass wheels, buy a bunch of different grits of super fine sanding discs, and have them at the ready to run through the grits. Start low if you have a serious nick in the tool's edge; start high if you just need a touch up.

I love my Worksharp.... I got it after watching one of Eric's tutorial videos here on OLF..

Yikes though.. I am not sure I could get excited about 10 or 20 of the same chisel for paring brace ends - just chew through them and then sharpen them all back up.... I mean I really don't like sharpening that much.. It's a means to an end....

if you find you need to sharpen your chisels often you either have poor chisels or poor sharpening or abusing the things.

I can use chisels for a while without issues. A sharp chisel is almost effortless , a dull one is a good way to get hurt. If it doesn't shave it isn't a chisel it is just a piece of metal.

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

I always have a bare spot on my left arm where I test my chisels.

"that super keen edge wants to roll or chip"

In over 50 years of woodworking the only time I have chipped a chisel edge is when I hit metal, like a screw or nail (or a bench dog dammit). If your edge is chipping, could it be that you are sharpening at too low an angle? try 25° for paring and see if that helps.

If the edge is rolling, it is a sign that it is soft. Could you have burned the edge while grinding - this will sometimes take the temper out of that area enough to soften it. If it always rolls in the same place, could be it.

Or it could be a defective piece of steel

heat is the enemy

if you heat the edge , and it can happen fast if you use a motorized grinder you over heat the edge , and this often shows signs of heat . That makes the edge very brittle.
if it is soft , it will roll. As far as end grain dulling a chisel that is a red flag that something is wrong with your chisel. I can shave end grain and when I can't a light sharpening will bring it right back.
Old chisels often had steel welded to the chisel body and over time you can sharpen right through that. DO NOT LET THE EDGE GET HOT. I use a wet stone like the tormek system also this is an affordable method to sharpen. It is in the details too sharp and angle is also not a good thing .
Hope this helps
https://www.youtube.com/watch?v=A_OZI_8k7h4&t=5s

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

What chisels are you using and how are you sharpening them? Every time I've had paring issues in non-abrasive woods, the issue has been my own poor sharpening job or a decaying edge I've ignored for too long.

In terms of advice: It really helps to find and cultivate a relationship with someone that can be your mentor for sharpening and tool setup. Standards are very uneven, even for shops that turn out nice instruments... find the shop that tends to use edges in preference to sandpaper, and it's likely you'll find someone that has a good understanding of sharpness and how to get there. I really did not understand what sharp meant until I started working with the luthiers here, and did not have a clue as to how to grind or hone tools for specific tasks until I had been walked through the process a couple times.

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For the times they are a changin'

- Bob Dylan

If you have not invested in power grinding technology, consider an 8" CBN wheel on a low speed (1725 rpm) grinder. It's too big a topic to get into on this thread, but it is one of two technologies we've introduced to the shop over the past two years that the boss considers game changers (the other is the Oscillating Drum Sander). Our CBN wheels are an 8" radiused face wheel from Tools for Working Wood and a radiused edge wheel from another vendor intended for turning tools. With CBN, there is no dressing, and the heat generated is passed largely to the steel or aluminum wheel.

_________________
For the times they are a changin'

- Bob Dylan