Questions answered – chisels and quality

Getting off the conveyor belt post

Re getting off the conveyor belt I posted earlier. It’s unrealistic to think that everyone can follow a vocational calling whereby they earn there living full time from craft work. If the 13 million people that enjoy woodworking in the USA all became woodworkers earning their living from it they would soon find themselves broke, on the dole and homeless. On the other hand you can enjoy the challenges of making your own furniture, building your canoe or boat, violin, guitar or build yourself a timber-framed home, garden shed or anything you choose by following a foundational training in woodworking and then diverting into any specific channel or channels you choose to. Build a shed, a workbench and follow my foundational course from cover to cover and in about 20 days, with about 20 hand tools, you can make a handmade guitar following instructions from another book. That should take you about 2 months total in evenings and weekends without neglecting your families.

If you work with just my book you can have enough to equip yourself for a lifetime of lifestyle Working Wood. How about that for a strategy?

Now then, one of my students emailed a question he thought that you all might be helped by if I answer publicly. Here is his email:

Hi Paul,

Hope all is well back with your family in the UK.

Just had a question you may want to answer on your blog sometime.

I have been working on my dovetails and, after about a half dozen good looking ones in Pine, I decided to try my luck with a small piece of quarter-sawn oak I had. What I noticed right away is that my chisels, while continuing to chop crisp lines, began very quickly to fracture and create a burr on the flat side of the cutting edge. I resharpened, went back to it, and found relatively quickly the same problem. I eased up on the chopping and they came out well, but nonetheless I feel like I shouldn’t have to resharpen two or three times per corner. What’s wrong here? Is it my motion? The wood? Are my chisels just poor quality? Just wondering your thoughts.

 

Side note: I’ve also noticed a tendency on the smaller chisels to skew to my right. Some are pretty significant. I can fix them, but I assume this is just uneven pressure. Correct?

 

Thanks Paul.

Answer:

The issue could be steel quality or type or something else, so lets consider steel type first. Without getting into technicalities of alloys, harder steel can of course be brittle and can readily fracture because though hard it may not be tough. Certain tool steels can have good edge tool qualities that have hardness and toughness in the same alloy. That’s what many toolmakers aim for. A problem with this is that they often require mechanical methods for sharpening, which in and of itself is generally overkill for something that needs only regular sharpening with the quick, simple, efficient hand methods I use and encourage others to use. For a more easily sharpenable cutting edge it’s better to use a softer alloy, but you cannot use steel that is too soft as the edge buckles under pressure whereas the harder edges actually fracture, creating small craters along the edge. This is not what you seem to have. The end result of course is that neither tool will cut well in either condition.

As you know, in general I advise the single- convex-bevel method for all edge tools. Having determined that both steel types have advantages, we should look at wood. Under certain conditions using chisels, as in your case, conditions arise that adversely affect cutting edges. Some pines for instance are even textured throughout the annual rings. The eastern white pine for instance is superbly even textured and has very minimal difference in density and hardness across the growth rings or within each growth ring. With softwoods from Eastern Europe there is often great variance in hardness and density. This can be because of the nature of the species, growth region, weather changes and season changes. Some years, the growth cycle has good levels of water and nutrition resulting in good growth across the seasons. When the weather is less extreme between the seasons, the result is more even texture across the two apparent periods usually associated with softwood growth. In other areas and seasons depending on the year, the growth ring has two extremes of soft and hardness, especially in softwoods. In hardwoods, on the other hand ,the extremes of seasons are much less, and oftentimes the two seasons of early and late growth are indistinguishable—fruit  and nut trees for instance; woods such as cherry or walnut for instance, and dozens of others.

Steel hard and soft – brittle or malleable

This then brings me to the real point. Seeing that hard tool steel is harder to sharpen because of hardness and softer tool steels bend unevenly along the cutting edge, we need to adjust our thinking in both cases. Assuming we have decent steel in either case, because both steel types can indeed produce practical edges, when we shift from paring pressure or slicing along or with the grain using hand pressure or light malleting pressure, we have no problem, but denser hard-grained wood such as oak often require a slight shift in strategy. Your problem may have nothing to do with steel quality or choice at all. It often requires nothing more than creating a steeper bevel right at the cutting edge. Remember that the shallower the angle of a cutting bevel does not mean that the edge is sharper than a steeper bevel, but that it takes a little more effort to counter the resistance created by a steeper bevel pitch. In your case it seems you have more malleable steel that may well be tough, but with a shallow angle the steel buckles. This is often especially true when using mallet blows. Paring pressure may be around 20-30-lbs pressure. Using a mallet blow may increase this to 80+lbs. Under such pressure the edge will either fracture or buckle depending on the alloy and the quality of the materials used. Try altering the pitch by as much as 5-degrees or even more and see if this helps. If it does, most likely it will, you are set. If it doesn’t you may need to invest in different chisels.

Once you have chopped, you can re-establish the 30-degree bevel over two or three sharpenings and need not go all the way back to 30-degrees at once unless of course you need to or don’t mind wasting steel and time.

Re  Buying replacement chisels

My experience proves to me that this has little to do with cost. I have used Marples’ (definitely not UK Irwin) blue-chip chisels since 1965. I am on my third set, but not because of weakness or failure but because I use them more than anyone I ever met and I love them. At the school in the UK I use chisels made for Aldi, the supermarket chain, they are about some of the best I ever used and we really use them heavily, probably more excessively than anyone else. They cost £8.00, $12 usd, for a set of four and a sharpening stone that’s pretty useless. I have so far, after three years of use, been unable to find any fault with them. Now the stuff Irwin makes, and Stanley, with steel tips and ergonomic plastic/rubberised handles, I have no time for because they are extremely uncomfortable, feel really bad in the hand and they encourage a throwaway mentality in tools. These companies are especially bad for craftsmanship and should wherever possible be boycotted until they get their act together.

3 comments

  1. John says:

    I purchased some Marples Blue Chip chisels off of ebay. They were pricy @ about $75 US. I think that I didn’t get hurt too badly on price since I’d been watching them before and since. I’ve seen them go for much more and not much less in unused condition.
    They are very nice chisels though and I’m happy with their performance and the purchase.
    Fairly inexpensive chisels that I’ve heard good things about but can’t confirm woud be the Narex line. Highland woodworking (I just bought an Eclipse coping saw from them, nice lil saw!) and several other woodworking sites carry them.
    I wish we had a viable solution for $12 US here in the states! If someone knows of some than I’d be willing to give them a try.

  2. rpriceca says:

    Paul, when you say, “I have used Marples’ (definitely not UK Irwin) blue-chip chisels since 1965.”; do you mean that one should buy the “Marples” stamped blue handle chisel and not the “Irwin” stamped blue handle chisels. I only ask because some sellers call them “Irwin Marples” even though they only have Marples on the handle. I’m confused…

    • Yes, these sellers know people are looking for the original Marples brand which were Sheffield UK made and not the inferior models now made in Asia. I have contacted some of these sellers who mostly say the same lame lies like “We haven’t changed the old image out.” They know people don’t like the imports but that’s not so much what bothers me. What concerns me is these huge companies charge even more for their products,have them made in countries exploited for low cost yet sell at high profits on the same brand. This global export import exchange of consumerism ruins local businesses and economies and controls what we can or cannot buy.

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