The Problem:
I am using some cherry scrap pieces to practice since this is the wood I’ll be using and I am having a hard time paring away the wood between the pins. What I did was I used a coping saw to take away a lot of the waste and then I tried chiseling down to remove the rest. I am going across the wood fibers and at this point I was not sure if I was doing this correctly – I was pounding away with the chisel and it just did not seem right – I tried pounding the chisel close to the scribed line and then turning the chisel horizontal to lift up the fibers – but that did not work well because I already removed a lot of the wood so there was nothing to rest the chisel on while going horizontal – I think my chisels are sharp. My chisels worked well on the tail board – but maybe trying to chop the waste going across grain on cherry wood requires a different technique – I do not know – I just know it should not look like this. I thought maybe I just need to pound away with the chisel – it seemed like that was not working nice either – I cannot find a decent video on the technique involved in removing waste between pins with a chisel – the one I did see used a soft wood. Any suggestions?
Replies
Tom,
You're right that it shouldn't look like that...
There have been so many articles and discussions about dovetails that it seems you could take your pick. So I'm not gonna use your question as another opportunity to wax lyrical on how I do them. Just to the point you raise -
1. Your chisels must be sharp and relatively low angle.
2. Forget the coping saw, it only make things more difficult.
3. Cherry is soft enough that it will smash if you use too much force. Ease up a bit.
4. Make the vertical strike along your scribe line, then use the chisel horizontally to pop out the whole chip. Take small bites. Make sure the piece is solidly supported by the bench - there should be no bounce when you strike.
5. If you do this from both sides of the board you will eventually meet somewhere in the middle with an unlovely portion, but that should be quite small.
keep trying...
David Ring
http://www.touchwood.co.il/?id=1&lang=e
Thank you David - I was thinking of trying the non-cope saw method of chiseling down the scribe line and then horizontally popping out the chips - I have seen videos of that. I had seen the cope saw method and it looked easy - I did not get the cope saw close enough to the scribed line - I was rushing it. I tried using my body weight to put pressure on the chisel to slice off the waste but with the ridges already created that did not work well either - I can't wait to try your suggestions tomorrow. I noticed in all the videos/articles I read - most of the attention is paid to the geometry and sawing aspects of making the joint and not enough emphasis is given on the chisel work required. In fact in one book about joinery on the section for hand cut dovetails - the instruction is given to pare the waste between the pins and not so much as an illustration or even some in depth explanation is given. I think most people who are learning to do dovetails are also new at using a chisel but the articles/videos assume knowledge of that skill. I am adding this comment for anyone who is an author who may be looking for tips on how to put together a more informative article on hand cut dovetails. Removing the waste is something that is a challenge for me - I am happy with my saw cuts but they need fine tuning as well. Also I made a 1/4 inch pin and I do not have a thin enough chisel so when I scribed the lines for the pin the pin came out a little too thin so when I forced the two boards together it snapped off - which is what you see missing in the picture.thanks for the comments-suggestions.
Tom,
A few ideas came to mind,but then I read most of them in David's reply!
A couple of things struck me....The repeated reference to 'pounding' the chisel seems a bit excessive.If the chisel is truly sharp,and by the look of the photos,it might not be, more of a sharp 'tap' should do the job,[or taps if necessary].
Using a jewellers saw in place of the coping saw very often gives [me] good results.The blade is VERY fine,as are the teeth,and I find almost all of the waste can be removed with quite a degree of accuracy,leaving only a very small amount to be trimmed out with your chisel.
You may find that clamping a small piece of waste with its straight edge alinged along the bottom of the pin,acting as a flat 'guide' will help you keep the chisel perpendicular.
BUT...the chisel MUST be SCARY sharp!! Try it, Good luck, Robin
Your photographs point to three possible causes of the problem:
If your chisels are sharp then the problem is almost certainly 2. There is, as David pointed out, more than one approach to removing the waste, and he suggested one.
I take a different approach to him and mostly use the method you described, ie, remove the bulk of the waste with a coping saw between both the pins and the tails of through dovetails, or between the tails of lap dovetails. I frequently use another tool as well; the router with a small diameter cutter and a side fence-- it works very well to remove most of the waste.
Anyway, back to your chiselling problems. Let us say the gap between you pins is 18 mm (3/4"), which is not unusual in carcass dovetailing, or even some drawer front lap dovetails. Just because you can get a 3/4" wide chisel in the space to pare to the shoulder line, it doesn't mean you should use one immediately after sawing out the waste with a coping saw. Consider starting with a very sharp 1/4" chisel. Pare a slot in the waste down to the shoulder line using no more than your hands and shoulder to push the cutting edge of the chisel through the wood. Drop that chisel, pick up a 1/2" chisel and widen the slot using the same method. Drop that one and finish paring to the line with your 3/4" chisel.
You'll find a method that works for you with practice. Try both the methods suggested so far and I'd guess your technique will soon improve; but don't make me come round to your place and demonstrate how to mark and cut 'five minute dovetails' in the rear corner of typical drawer boxes, ha, ha. Slainte.
Richard Jones Furniture
Edited 10/5/2008 9:23 am by SgianDubh
Hello Tom,
I must agree with Dave and the others, judging from all of the crushed wood fibers shown in the photos, I would start by checking the grind and keenness of your chisel edge and go from there. Can you post some pictures of your chisels business end?
Bob, Tupper lake, NY
Two things:
1) From looking at your photos, your chisels are most definately NOT sharp. If you coped first, you should be able to pare down to your line without tearing out the end grain. The waste should just peel off, with no need to go at it horizontally. (In fact, that's one way to test for sharpness -- if you get tear-out like your pic shows, you need to go back to the stone.) BTW, I prefer to use butt chisels for DTs -- easier to control the angle of the tool.
2) I respectfully disagree with David on coping. When doing dovetails in hardwood, I find the coping saw to be a major time saver. I cope the waste to about 1/16 - 1/32 away from the line and pare it in one, or maybe two, cuts, doing 1/2 the depth of the board from each side.
With pine or poplar, the wood is soft enough to skip the coping saw, but with harder woods, the coping saw is a time saver for me. (I always cope joints in oak, e.g.)
FWIW, there's what looks like a nice article on RX for messy dovetails in this month's mag. Haven't had a chance to read it in depth yet, but you might find it helpful.
Mike Hennessy
Pittsburgh, PA
Mike Hennessy,>With pine or poplar, the wood is soft enough to skip the coping saw, but with harder woods, the coping saw is a time saver for me. (I always cope joints in oak, e.g.)Thanks ! You made the light bulb go on for me. I , duh, never got it why Frank Klausz chisel only method could differ so much with Ian Kirby's cope saw method which seemed like a wasted step. The English used oak for the secondary wood and the Americans used the softer wood.I get it now ! Saw the hard stuff chisel the soft stuff. I nearly always work with very hard woods banging away when I should be sawing. I did saw quite a bit but always thought I "SHOULD" be able to just chisel and I did not like the sawing; left too much wood on to pare off. But now I have rethunk the whole approach.Reading over this it sounds like I am being a smart alick but seriously, I never got it until this moment.Thanks
Use a bit of camilia oil on the chisel and or wet the end grain as you pare off layers
Geometry of the cutting edge plays some part. I used to think the steel in my Swiss army knife was poor because it would dull quickly and would not cut easily when sharp. Since I got into wood working I have put on a shallower angle and used the blade with more awareness and the blade stays sharp longer and cuts much easier. This sounds counter intuitive I know.
The angle I have on it now will easily cut through a good size plastic wire tie. Try that with the angle that comes on a Swiss army knife and you will see what I mean.
Through sloppy sharpening it is too easy to round over an edge or get a wire edge and not hone it off properly; many people wind up breaking it off and thinking they did it right only to find under magnification a jagged, blunt or folded over wire edge.
As I often say, if under magnification you can shave a curl off a single arm hair you are getting close and when a bunch of hair on your arm jumps off your arm and runs away when they see the blade approaching that is sharp enough.
The challenge is now how to keep from damaging that edge; balance this with a steep enough sharpening angle that the edge does not get dinged just from the wood grain balanced again with how hard you hit the chisel.
For trimming the last bit after chipping or sawing the bulk out of the way switch to a parring chisel with a shallower sharpening angle and push the chisel rather than bang at it with a hammer or mallet.
Do you see? If you use one chisel and do not sharpen before the last bit how the chisel has gotten dull from all the heavy work and now for the critical last stage it needs to be fresh and sharp ( and preferably a shallower angle ). How do you like that! You now have an "excuse" to buy more tools!
For the final parring Ian Kirby locks the chisel in a two handed death grip and forces the chisel down vertically with his chin. Other people, myself included, stand the board upright in the vise and pare across the grain using the strength of our legs and an elbow locked at our side. Easy to blow out the back side if you slip. I do pair from both sides if it is a through dovetail.
No criticism of Mr Kirby what I am trying to illustrate is how to generate enough force without a hammer.
Can change technique to compensate for fatigue or joint type etc.
Practice, Practice, Practice, Practice, Practice, Practice, Practice, Practice . . . . etc., etc., etc.,
The photos you've taken strongly suggest that your chisels are not sharp. As the others on this thread stated, crushed end grain is a symptom of a dull chisel, and while some crushing is really hard to avoid in really soft wood like eastern white pine, cherry should not look like that.
So - here is a practical test for your chisels. Examine the edge under a magnifying glass. You should not be able to see anything other than a straight line of bright metal. If you can see any chips, honing furrows (the way a chisel looks when you get it straight from the manufacturer - lots of parallel lines), or rolled edges, it's dull. At least the microbevel (if you've used one) should be a mirror with no visible scratches. At least 1/4" of the back of the chisel should also be a mirror that you can see yourself in.
If this is the case, skip the arm-shaving trick (I've seen someone shave off a slice of skin doing that!), and get a piece of medium-weight printer paper. Holding the piece of paper vertically between your thumb and forefinger, you should be able to slice a wedge off of the side of the sheet with just the weight of the chisel alone. If the paper tears at all, the chisel isn't sharp.
>Arm hair test
I agree is not practical, could be dangerous, and pretty soon your arms look quite ridiculous. Though I would wager you will slice a hunk of skin off only once. : )
If I am testing a semi dull blade I touch it to the flat of a finger nail. Works well for twist drills, saw blades router bits etc. If it bites it is sharp enough to keep going, maybe. If it slides and hardly bites it is too dull to continue. A properly sharpened blade to the standards we are shooting for here will not only bite the surface but will have that added indescribable little extra micro penetration of the nail that makes you say oh s**t . It is disconcerting every time but have no fear you won't cut your arm off.
I no longer test the edges when I sharpen. My system, if I follow it step by step, produces the ability to shave a curl off a single hair every time without fail and, I must emphasize, still maintain the flat back and intended sharpening angle. Something that stropping may not accomplish
Once you get to this level of sharpness you begin to look at single edge razor blades and exacto knife blades as only "fairly sharp".
PS: paper has a lot of grit in it from the material source. If we want to split hairs, as it were, you may be taking that keen edge down a peg by using paper test. At least don't keep going slice after slice no matter how fun it is.
Edited 10/5/2008 8:37 pm by roc
Today I tried the method David suggested and here is a photo of the pin board - still getting the smashed fibers but at least I was able to get the face fairly vertical with none of those fibers really protruding out to the point they interferred with the fit. The second pic is the completion of my attempt - so not only do I have to learn to clean up the walls between the tails or pins, I also need to work on maintaining a straight line across the board and also to take is slower with the chisels. I agree my chisels are not sharp enough - I am using Narnex chisels straight out of the box - they looked sharp enough but I guess not sharp enough to cut cherry cross grain. Like hand cut dovetails, sharpening chisels is another thing I will have to learn.I would sure like to cope out the waste - the chopping took forever but I sure got better results than my first attempt. Thanks for the feedback - suggestions - Tom.
Tom,OK, it's getting better. I'd say that now you need to concentrate on 2 different things:1. Get those chisels really sharp.2. Refine your system for making dovetails. What I mean by that is to find a series of steps that works for you and that you refine systematically. There are many little steps in making the joint that will determine all together how it turns out - How to scribe the lines? With what saw do you cut? Do you cut the line or to one side? Undercut the chisel lines? Etc. etc.
I don't want to take issue with any of the methods described here, including the coping saw proponents. There are lots of ways to get an excellent end result. The point is to become thoroughly systematic in whatever way you do it, consider every step you make and how to refine it so that the whole thing gets better all the time. Your learning curve is shooting way up now...keep at it.best,
David Ring
http://www.touchwood.co.il/?id=1&lang=e
Actually I am impressed. My first attempts were not as good but I was having saw issues. To pare to the line on the half pin areas you will need a sharp fresh chisel. Usually by the time you get to cutting dovetails one has been doing some planing and has learned to sharpen. You are getting a bit ahead of your self.By the way the only chisels I have come across that are sharp enough out of the box are the Japanese chisels. Every body else is just playing around. Don't assume the angle on the chisel is the best for what you are working on. Sorry if this is frustrating and overwhelming. One wants to just make things rather than spend allot of time doing research and remaking the tools but wood working takes a lot of preparation and skill, much more than people realize. But it is fun so learn to enjoy all of it not just the results.
"By the way the only chisels I have come across that are sharp enough out of the box".....
I have not found any like that. Tom said his were Narnex (think he means Narex). Now these are no longer made in Chzeckoslovakia (spelling?) when they were very nice-the last I saw were sorry items made in India and Oh My GoodnessGraciousMeMan they were not goodatallman...Better to leave them in the box. (;)Philip Marcou
You're getting close. FWIW, I never worry too much about the end grain tear-out you show in your pic. You don't get much (if any) strength from this part of the joint anyway. From the pics, I would say you need to work on getting your cuts lined up a bit better -- things don't look real crisp in the pic of the assembled joint. You may also be rounding the edges over when you pry the waste out with your chisel.
Practice getting your saw cuts dead on. Hog out the waste just short of the scribed line, and take final paring cuts to sneak up to the line. Otherwise, your chisel bashing will push the cut back over the line. I like to undercut this just a hair. (Meaning the chisel is angled away from the line about 1 degree or less, so the cut is just a tad deeper in the center of the joint.)
You might want to make some practice joints in pine or poplar. It's easier and faster, so you can get more practice quicker without wasting a lot of cherry. And take your time. Since, I would guess, you're not making your living doing this, accuracy is more important than speed -- that'll come later as your skills develop.
Mike HennessyPittsburgh, PA
I just wanted to once again thank everyone for their comments. I have a lot of practice ahead of me and I need to also work on sharpening my chisels - Tom
Tom,Before you walk away from those dovetails and start all over..hit them with a smoothing plane. I think you might be surprised how they clean up.
Tom,
I'd like to add a couple of pointers that work for me. I use a fret saw instead of a coping saw. It has a thinner blade and I find that I can cut quite close to the line without crossing it.
The other thing is that you need to sneak up on the final fit. Expect to pare the sides of the joint a bit after making the initial cuts. If you try to get it dead on from the first saw cuts, Rob Cosman notwithstanding, you're bound to ruin some of the dovetails. When paring to the final fit, take very thin cuts with a very sharp chisel rather than hammering away. Resharpen the chisels when they no longer slice cleanly through the wood. Take your time...this isn't about speed.
You could read a newspaper through the gaps in the first dovetails I tried to make. I decided to practice every day until I got better at it. Eventually I started to identify the things that were causing the joint to not fit together and was able to correct them. There are a lot of good sources out there to show you how to do it, but if you practice and are patient, you'll get it.
Jim
Tom - From your comments and pictures, there a couple of things going wrong that will prevent success no matter how much practice you get.
One of them is the sharpness issue (which everyone else has noted already) - no chisel is sharp enough out of the box to use for dovetailing. Again, you need to see a mirror image of yourself in the back of the chisel, and at least a small bevel on the front that's equally well polished.
The second is driving the chisel down all the way through the joint - that's the cause of the chips out of the flat face of the back side of the board. That's why you'll often see a dovetail teacher chop or pare halfway down into the joint, then flip it over and finish from the other side - you want the fibers you're slicing off well supported. It's not that it's absolutely impossible to go all the way through with a chisel (the knifed guage line helps here), but it takes a degree of finesse not recommended for a beginner's first attempt. Going halfway and flipping the stock over solves the problem, little finesse required.
Finally, you need your scribe line to be deep - a little scratch may be OK for Franz Klaus, but not for most of us. And, you want that last slice where you put the chisel in that scribe line to be micro-thin - if you've any substantial slice to take, the chisel will be forced down below that scribe line (especially with a mallet), and the pins won't fit flush on the bottom.
Hi, sorry to be a latecomer in this discussion but... your chisels are not sharp. It has taken me years to appreciate what is sharp and what just seems sharp. My chisels, which I know are sharp, cut wood fibers cleanly (the pictures I saw showed wood fibers that were crushed). A sharp chisel can be seen by eye: both sides should be like a mirror! Really! The "sharp" blade that you get from the box is not sharp at all. You can grind and whet all day long but even "razor sharp" is not enough. I'm sure there are others who will back me up. A really sharp tool will "sing" when it cuts wood! Whether it be a chisel or a plane blade.
Tom,
Apart from the critical necessity for sharpness of chisels I would suggest the following two items to help if you prefer to hand saw, chop chisel and pare the waste:-
1)You need a firm base on which to chop i.e use a mallet on a chisel- I use either a piece of chip board or mdf around 3/4 inch thick.Chisel musn't go bouncey bouncey....
2) Break up the waste with several saw cuts apart from the two that define the tails or pins-I assume you are doing these joints by hand . I just use my bandsaw for this (making the extra cuts) and the purists can freak out but I always get clean doves quickly in either wood or steel -I believe.
3)Make sure that you have well incised with a cutting gauge or marking knife the limits to which you chop so that your chisels easily register on these base lines. Your extra saw cuts will ofcourse stop short of these lines and this is not too hard to do. When you want to chop out the waste don't go straight into the cut lines come out a bit and angle the chisel slightly away -after this you can either pare or chop using the incised line as reference.
Keep at it, but sharp chisels are needed first.
Can you let us see the business ends of the chisels you are using?
tom,
Have a piece of hardwood placed across the joint and lined up with the scribed knife line. Start by driving the chisel down on the line vertical with the back of the blade lined up and flat to the hardwood. Then move the chisel out away from the hardwood about 2mm, push the chisel handle away at the top until the chisel is at about 45 degrees to the timber being cut and drive down. This produces a shanfer like 'V' cut. Then drive the chisel in the first step vertical again, then at 45 degrees and continue moving away by 2mm each time until you are half way through the timber.This produces a wide 'V' cut with a vertical face at the scribed line.
Turn the timber over and start the stages again until you cut throug the timber.
If cutting the tail parts donot force the waste timber out of the joint.
This method is taugh by Frank Klauss and I have used it for 20 years or more teaching furniture craft students all with sucess.
good luck and regards keith33
Ok with out starting a fight may I’ll offer what I show new carpenters who are looking to sharpen there tools. Regardless of what system you decide on from oilstones, water stones, diamond stones et et keeping a content angle is the first step in sharpening. As your skills grow we can discuss different angles on chisels and you can find your own happy medium. When I was taught to sharpen (no, it wasn’t putting a edge on bronze tools) the hardness part was to maintain that content angle. It doesn’t matter what grit or type of sharpening system, if you can’t maintain a content angle you’ll never be able to consistently produce a sharp edge.
Ok here’s the part where I admit that I’ve got a sharpening fetish and own a huge collect of stones, and jigs. The one that I reach for when its time to sharpen (not touch ups) is http://www.woodcraft.com/images/products/833173_230.jpg the Veritas MK II. Simple to set up and easy to use. Fits all sharpening systems and even better can handle chisels, blade irons and spoke shave blades.[img]http://www.woodcraft.com/images/products/833173_230.jpg%5B/img]Edited 10/6/2008 9:45 am ET by IHammerI
Edited 10/6/2008 9:46 am ET by IHammerI
A good part of my first day as a Timber Framer was spent trying to sharpen a 2" chisel. The job got easier as my sharpening skills grew. I would suggest practicing your sharpening skills before you worry about your woodworking skills. The task at hand will get much easier with the tool in hand at it's best. After learning how to shave Oak with a 2" chisel I can't imagine needing a mallet for anything as small as a Dovetail.
Good Luck Dave
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