I cannot seem to make a through mortis without tear-out. I am working with walnut and have tried on my bench mortiser and using a forstner bit and chisel. What technique is best for a beginner? Any link to instructions or suggestions for books would be appreciated. (This seems to me to be one of those, “No question too basic” kinda things but I am most frustrated.) 🙂
Discussion Forum
Get It All!
UNLIMITED Membership is like taking a master class in woodworking for less than $10 a month.
Start Your Free TrialCategories
Discussion Forum
Digital Plans Library
Member exclusive! – Plans for everyone – from beginners to experts – right at your fingertips.
Highlights
-
Shape Your Skills
when you sign up for our emails
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply. -
Shop Talk Live Podcast -
Our favorite articles and videos -
E-Learning Courses from Fine Woodworking
-
-
Replies
O.K let's look at the bench mortiser first:-
Assuming the chisel and augur are set up correctly you can get a clean exit by a) using your mortice gauge and a scribe knife to mark out the exit-just the same as the entry. The sharp points of the gauge will cut the long edges and your scribe or knife will cut the ends, across the grain. b)make sure you have a back up piece under the walnut and it should not be too soft.
c)you can go half way from each side-but that is not the way it's meant to be.
d)you could partially chop by hand at the exit side-painfull.
Without going into too much detail on the chisel and augur- the augur needs to be sharp and set so that it is cutting ahead of the edges of the hollow square chisel which shaves the walls of the hole square. Too much projection results in break out, same for insufficient projection.If these tools are blunt there will be burning and too much force required.Examine the chisel- it should be very slightly bigger at the working end to reduce friction(at least the good qualityones are), and smooth.
I don't know of any books to recommend, but I do know that the hollow square mortiser can make clean mortices-fast and accurately.
Hope this is something to go on.
Thanks, Phillip and Boss. Very helpful.
Paul: My latest try was coming from both sides with better but less than satisfactory results. I suspect one of the problems is I am using the augur and hollow chisel that came with the mortiser. (There is a squeaking noise when I turn it on.) I have decided to order some new ones and have just about decided on the set from Fisch. Is that a good choice?
Is your suggestion to scribe the exit to ease the exit point? By that I mean to (terminology fails me here) cut the wood fibers at the through point? I will do that on my next attempt since it makes sense if I am interpreting correctly.
Boss: I was not coming from both ends. Again, thanks.
Once more into the breach I go! LOL
Jim
My earlier post was deleted... long story.
In this case, hand tool methods are the reference method to guide you. You'd never NOT come in from both directions if chopping a mortise by hand. Machine work needn't be any different. I've worked in, managed, and owned busy millwork shops making custom doors. Mortises were of course machined, but a reference face was selected and the through version of the joint was cut coming in from both edges registering the reference face to the machine's fence for both cuts.
I see no particular value in a set up that allows you to plunge all the way through from one side, reliably, as opposed to simply coming in from both sides and meeting in the middle. Especially true, since I suspect, you are making just a few copies, or maybe even one door. All you have to do is flip the board and finish the cut from the other edge. If you register the same face, then there is no way you can blow out the other edge. Set the depth stop on the mortiser to go 3mm deeper than center, make your cuts from both edges, and perfection should be the result.
By all means, incise layout lines if you want to - again using one reference face against which to run your gauge. Of course this face will be the same one you register against the mortiser's fence.
THE SECRET OF WOODWORKING, is taking the time to make marks on stock where cuts will be made - regardless of whether you are using a machine or hand tools. Taking the time to make a mark of some kind (pencil, incised line, etc.) will prevent errors resulting in a real waste of time and valuable stock.
If you can go slowly with the first 1/8th or so of the plunge then you should have clean arrises. When you're making the cuts don't let the chisel come up all the way out of the mortise - it should eject the chips by itself - keep the chisel down in the mortise to avoid a slip-up that could bugger the clean arrises you made when you cut the first eighth inch or so.
Unless you own a commercial-grade floor mortiser plunging too quickly will cause some deflection from side-to-side or even twisting that will spoil the clean arrises you need to make the joint look good when assembled.
Of course, all your cutting implements should be clean, sharp, and the best quality you can afford. The chisels that come with consumer grade mortisers are almost by definition ready for the bin.
Edited 8/8/2006 10:16 am ET by BossCrunk
Sansmnd,What Boss Crunk was saying is that one needs to has to be precise in making mortises. In other words, one needs rigor in making mortises. That is where the term "rigor mortise" originated. Enjoy :-)
MelPS - Developing woodworking jokes is very difficult business.Measure your output in smiles per board foot.
Excellent.
Funny! Thanks for the grin.
Mel,
When it comes to mortise jokes, I always say: the mortiser, the merrier. And if the Boss got a chuckle, it's a good one, you bet your sweet arris.
Cheers,
Ray
brilliant
Quietude,Thank you very much. I am a frustrated stand-up comic. Given the poor quality of much of my humor, it is easy to see why. But you and I both thought that the "rigor mortise" quip was pretty good. Actually, I even got a response from Boss Crunk on that one. MelMeasure your output in smiles per board foot.
I suspect one of the problems is I am using the augur and hollow chisel that came with the mortiser. (There is a squeaking noise when I turn it on.)
you have received plenty of good advise on how to avoid the tearout, but do you have the chisel and bit set up properly? there should'nt be much of a "squeeking noise".
make sure you have enough clearance between the bit and the chisel, or you will not have very good results regardless of your methods...
I have indeed received much good advice. As with all tools and techniques, set-up seems to be crucial. I really appreciate the New Woodworkers' Forum.
The proper way to set up a mortise chisel and drill bit is to chuck the chisel about a dime's width loose. Then chuck the drill bit tight against it. Then re-chuck the chisel tight. This leaves enough clearance between the drill and the chisel. However, you still may get squeaking -- I often do. I keep a wax toilet ring on my bench for lubricating screws, etc. If my mortiser is howling, I just touch the spinning bit to the wax and all is peaceful again.
Mike HennessyPittsburgh, PA
There's an article in FWW this month on setting up a hollow chisel morticer. If yours is squeaking, it may need some fine tuning and lubrication.
"I cut this piece four times and it's still too short."
Came accross this today quite by accident. FWW graphically does a great job!
http://www.taunton.com/finewoodworking/ToolGuide/ToolGuidePDF.aspx?id=2477
"Came accross this today quite by accident. FWW graphically does a great job!"
Great find! This is why this forum is so valuable. Thanks, Dock.
Okay, time for some feedback from the guy who started all this. I am now making "satisfactory" mortises. As those of you who offered advice surely knew, my problems were myriad: measuring, marking, layout, set-up and technique. Once I went back to square one and started using many of your ideas, I got progressively better. (Going through both sides was the key for me.) The difference between post #1 and now is remarkable. I hope all new woodworkers here are able to benefit as much as I have from your expertise and willingness to indulge us. I suspect I will be back with more "no question too basic" kinda stuff. :)
Jim
The squeal is a tell-tale sign that the augur does not have enough relief between it and the hollow chisel. This is a set-up problem that will ruin the best of hollow chisels (the sad voice of experience here). Check out the very good article on morticers and the sdebar on set-up in FWW not too long ago. Sorry that the specific issue does not come to mind, and I can't seem to lay my hands on it right now.
Someone else mentioned that article in one of the posts in this thread. I thought I had all recent issues of FWW but can't find the article. Does anyone know if it is available on-line? Link? Can I order a back isuue? I knew the squeal was a problem when I heard it but don't know what I might have wrong with the set-up. For now, I just keep it lubricated. I surely don't want to spend money on new chisels if the problem is due to my ignorance, the most likely cause.
Never mind about the article. I answered my own question with a few clicks of the mouse. lol
Edited 8/15/2006 2:10 am ET by sansmnd
I believe it's in #185.
I'ts on the magazine side of the website also. Put mortising machine in the search box and then click on the link for Master the Mortiser.
Since the house is on fire let us warm ourselves. ~Italian Proverb
You did not mention the width of the boards you are mortising, but on narrow boards you should be able to start the mortise on the exit side and what little bit of blow-out you get on the entrance side probably will be hidden by the cheeks of the tennoned board.
John
I am trying to make a "Craftsman Style" book shelf. No doors or frames. The mortises are actually through a 12 1/2 inch wide side panel with tenons on the ends of the shelves that pass through the panel to be wedged. Important information I left out, huh? :) (I got the plans from the FWW site. I'm at my office and do not remember the name of author of the article.) I'm begining to think I may have picked a project above my skill level but I'm sure learning a lot. So far I've not ruined any of my panels since I've been praticing on scrap.
Edited 8/8/2006 12:13 pm ET by sansmnd
I am trying to make a "Craftsman Style" book shelf. No doors or frames. The mortises are actually through a 12 1/2 inch wide side panel with tenons on the ends of the shelves that pass through the panel to be wedged. Important information I left out, huh? :) (I got the plans from the FWW site. I'm at my office and do not remember the name of author of the article.) I'm begining to think I may have picked a project above my skill level but I'm sure learning a lot. So far I've not ruined any of my panels since I've been praticing on scrap.
Coming in from both edges should give you the clean look you must have for a project like this. If there's to be a problem, let it be in the middle of the mortise not the part that will show or potentially show.
If you still have problems, there is something wrong with your technique (plunging too fast) the chisel is deflecting (it everything nice and tight?) or the chisel is of poor quality and/or needs honing.
Obviously, the 'show side' of the joint is the most important. You have to have clean arrises on that side.
This is pretty much a beginner project. Arts and Crafts stuff is rectilinear and lends itself very well to machine woodworking.
Just keep practicing on scrap until you've executed three clean joints.
BTW, what kind of machine are you using?
Edited 8/8/2006 12:39 pm ET by BossCrunk
Boss -
Thanks for the encouragement. I am using a Delta Bench mortiser. I don't remember the model number right now.
Slide the board to the side of the chisel, loosen the chisel and make sure to align it square to the face of the board, then tighten the chisel. Your problem may be that that chisel is oriented slightly askew of the face, and therefore the edge, of your stock. This causes the mortise itself to be improperly oriented (obviously) but can also cause a small mortiser to labor causing jerkiness and a generally lousy cut.
Make sure the stock is four-squared properly. The edges must be parallel to each other and the stock of uniform thickness if you come in from each edge and meet in the middle.
Again, thanks to all who took the time to read and respond. It has given me much to think about. There is no doubt I need to learn skills and techniques I do not yet have and I am even more motivated to learn them. You guys have been great!
Jim
P.S.
You should have seen me trying to form the tenons on the ends of the shelves. Now THAT was a hoot! Not at the time, but in retrospect.
When doing through mortises that must be clean on both sides, I usually start the mortise from both sides with a router -- either on the table or with an edge guide. Then I finish off the mortise & square off the corners with a mortiser. Much easier to get a router to register accurately from than a mortiser with a crummy fence.
Mike HennessyPittsburgh, PA
I'll say this - the best way to learn how to use a mortising machine is to learn to chop them by hand. Then you'll understand exactly what a mortising machine is supposed to do and how important stock preparation and keeping the machine aligned properly really is.
When you chopping by hand, the first cuts that cover the mortise are very important as they define the arrises. Cut too tentatively and the walls won't be smooth. Go at it too hard and the chisel will twist slighly causing you to go outside your layout lines or have skew in the first part of the mortise wall.
Sorry but the name Steve does not register, I must have missed something.
The attached shows my understanding of what sansmnd wishes to do. These were to be a three tier chair side table for a sick friend but he suddenly died and I never finished it. I have all the staves prepared so may carry on one day.
Done before I cottened on to superglue so some breakout shows but working from both sides would be a bind.
I had just wondered what our time zone difference was!
The likelihood of me gluing veneer to a workpiece to assure a clean exit hole in a through mortise is beyond remote.
Sorry.
Boss,
Once I glued a veneer patch over top of a through mortise that wasn't supposed to be a through mortise. It makes a nice unobtrusive repair, it was at the top of a turned leg.
I've tried all the remedies suggested, except the removeable patch. Backup boards work pretty well, once or twice, then they tend to bruise and allow breakout on the stock, unless they are relocated for every mortise - which is a pain after a while-it gets hard to find an unused spot on the backing board.
Hiding the blowout with the shoulders of the tenon only works if there is enough meat to haunch both ends of the tenon, where the worst of the blowout occurs. That takes more time, as does leaving the stock extra thick and coming back to plane off the blowout.
It is easiest for me to just cut the things from both sides, but different folks will have their own preferences. I worked in three shops before opening my own, and had to learn three different "right" ways to do things to keep the various bosses satisfied.
I have a set of reproduction windsor chairs in the shop now for repair. At first glance, the legs appear to be tenoned through the seat and wedged. But the "ends" of the legs are dummies-plugs. The real tenons are only about 3/4" long, and "reinforced" with screws driven into the underside of the seat at an angle. It's hard to imagine a maker concerned enough about appearances to go to the effort to put phony wedged tenons in, when doing it right wouldn't have been any harder. Glad I never worked in that shop!
Ray
It just never occurred to me to do anything but cut and meet in the middle.
Boss,
And wouldn't the world be a better place if more of us could do just that-- meet in the middle?
Regards,
Ray
Ray, I admire your openmindness. When I suggested a patch I did not mean smear the whole of the exit area with glue, just a fine line round the actual exit points to give support to the veneer.
I am only amateur and woodworking is just a hobby. On the other hand if I make a suggestion it is because it it is something I have done which works for me and I try not to work by rote but by reasoning. In this case the gentleman had said he is using walnut so I would not expect him to use stain or dye.
The shelves I pictured are quartersawn iroko and with my resources it would have been difficult to go in from each side, I was very pleased with the result even with tearout. That I will "lose" with professional wax but it will still be there.
Re the chairs, I recently repaired 13 pub solid wood chairs (factory made) which had been botched with screws in the same way. The short tenons had been glued, using just a lick of glue on the end of each tenon which did not reach the bottom of the mortice. My way round this was to add one inch thickening shaped plates on the underside of the seats and extend the tenons and mortices to provide a sturdy epoxied assembly. I get good service in that pub.
Regards, David
Wow, if working by rote will help me accomplish what Ray has then I'm all for it.
To wit:
http://www.davidraypine.com/portfolio.php?spgmGal=Tables&spgmPic=8&spgmFilters=#pic
You need to let the rote part of woodworking be rote. It frees the mind to do other, more difficult things.
Through mortises by machine are not 'other, more difficult things.'
Edited 8/10/2006 5:34 pm ET by BossCrunk
I am most grateful for the link you provided which now will be a frequently viewed item in my favorites list. My point however is that in the posts I have read Ray is never dismissive or bombastic, and in reply to my posts leaves me benefiting from a considered point of view.
And yes, his portrayed work is awesome!
Ray is a wonderful guy. I agree with you completely.
Boss and All,
I am, indeed one HeII of a guy. A legend in my own mind. Hard to find a hat that will fit a head as swelled as mine is at the moment.
Ray
And you're never dismissive or bombastic, either.
Boss,
Well I'll have to try a little bit harder. In the meantime maybe we can all of us get together and do each others' hair.
Ray
I wish you had not said that. Now I cannot wait to see who offers you the loan of their hat.
mufti,
Ooooh cooties! I'll stick to my own headgear, thanks.
Ray
I'd lend you my hat Ray--- but the brim would rest on your shoulders, it'd cover your mouth, and we'd not be able to see your lips flapping. Slainte.
Richard Jones Furniture
Edited 8/12/2006 2:42 pm by SgianDubh
Richard,
Umm...suddenly, it seems that my old hats all fit again. Thanks for the mental image, which deflated my swelled head. It is a tam-o'shanter, isn't it? With a poufy ball on top?
Bass ale was on sale this week. This one's raised to you.
Cheers,
Ray
Ray, I'd loan you my hat but I accidentally glued a piece of veneer to it.
Why would working from both sides be a problem in the example shown? The same series of stops used to provide symetrical mortises on both ends could be used to work from both sides. (The right half stops on one end are the left half stops for the other end, etc.) I should think this would be faster than laying each mortise out with marking knives or cutting gauges to avoid tear out, as Phillip proposes. Using superglue on any project to be stained, particularly in any open pored wood such as oak or mahogany, would be highly fraught with risk. Any superglue left on the surface or in the pores will play hob with the staining.
On those particular boards I might consider doing the mortises from one side on boards left 3/32 over thickness and then just planing off the breakout with the extra thickness, but that is seldom an option.
Edited 8/10/2006 8:08 am ET by SteveSchoene
Steve, you keep beating me to the punch.
We apparently seem to be alike in the sense that we are willing to let a simple process be a simple process.
Breakout may happen whatever power tool is used. just make sure it does not affect your work. Thus superglue smeared round the exit line and topped with a bit of veneer goes a long way to stop the problem. Clean it off with s/glue remover. also I replaced my small mulico holddown with a cheap machinists X/Y vice, packing the morticer up to allow clearance. This makes locating the work a lot easier.
How does breakout occur if the chisel never exits the joint?
Come in from both edges.
O.K., brevity leads to obscurity. Yes you can go in from each side, but if you go straight through then backing up with a superglue veneer patch firstly gives strength to the wood fibres at the exit points and evidence of damage shows on the patch which is removed.
Secondly the enquiry referred to multiple mortices to receive tenons on the edge of shelves, the upright being just over a foot wide. From that I guess a thickness of 3/4inch, so going in from each side would be finicky. Throwing the vice suggestion in this case does not apply, but it does help in morticing stiles with accuracy.
Tomorrow I will post photos of my own experience with a similar situation, its now 8.00pm here and we eat late.
Is there anything that would persuade you to give a modicum of profile information?
Best wishes, David
Is this question directed to me as the OP? If so and you are asking for more personal information in my posted profile, I will be happy to oblige. If you mean "profile" of the piece I am working on, you seem to have it right. English - what a difficult language somtimes. I look forward to the pictures.
Why do we want to mess with a superglue veneer patch--it may mitigate tearout but this method also creates more complicated processes that have the potential for finishing problems should all the glue not be removed. The alternative is a simple flip of the board to complete the mortise from the other side. The setup for this is straightforward and quick, and costs nothing extra. The only "trick" is maintaining a single reference surface for locating the mortise. Mortising in from both sides was was how I was taught from the beginning--with brace & bit and chisels, and is absolutely as simple with a mortiser or with a router and jig.
O.K., brevity leads to obscurity. Yes you can go in from each side, but if you go straight through then backing up with a superglue veneer patch firstly gives strength to the wood fibres at the exit points and evidence of damage shows on the patch which is removed.
Secondly the enquiry referred to multiple mortices to receive tenons on the edge of shelves, the upright being just over a foot wide. From that I guess a thickness of 3/4inch, so going in from each side would be finicky. Throwing the vice suggestion in this case does not apply, but it does help in morticing stiles with accuracy.
Tomorrow I will post photos of my own experience with a similar situation, its now 8.00pm here and we eat late.
Is there anything that would persuade you to give a modicum of profile information?
Best wishes, David
What Steve said, just above.
Is there anything that would persuade you to give a modicum of profile information?
Why yes, commission a piece of furniture. Business is unusually slow at the moment. I'll tell you everything you want to know as long as your check is good.
The messages were not posted when I replied. My E mail server told me of you message but the latest on forum was mine to you. Sorry for the confusion!
I would give some serious thought to cutting joints like this using an up-cut spiral bit in a plunge router, plunging from the visible side of the joint, going in easy stages, say three or four passes for a 3/4" thick board. Build a jig from stuff in your scrap pile for accurate repetitions. Well worth the time, just like careful marking out. Tuck all of the responses you've gotten on this thread into the back of your head for future reference. Wonder why I like this bulletin board?
The responses are indeed tucked. :) I too love this board.
Place a sacrificial piece of hardwood on the table of your mortiser. Clamp it in place if you can and firmly hold the stock you are mortising. If your mortise drill and chisle are sharp they should cut cleanly thru the work piece an make a clean entry into the sacrificial stock
Use a backerboard on the exit side.Regards, Scooter"I may be drunk, but you're crazy, and I'll be sober tomorrow." WC Fields, "Its a Gift" 1934
I am by know means the expert on this but I have found a way to do it that came out looking really good. I have tried the square hole driller, forsner bits, and hand whittling with chisels. None works as well as a router with a sprill down bit and a jig. I built a coat rack A&C style with wedged through tendons in cherry. It took me longer to make the jig then it did to make the mortises but they went through straight and clean.... just needed a little clean up in the corners.
You might want to try Peter Korn's book Woodworking Basics. It's available here through Taunton press or through your local library. This book teaches you as you build-up to a project that includes a wedged through tenon. It's very clear with a focus on hand-skills.
best, Peter
Hi Sansmnd there is a video out buy a man named Jim Kingshott that goes into great details on making through mortises with hand tools. I have seen the video at toolsforworking wood. Jim died a few years ago and I don't think they have been re realeased on dvd. He also has excellent videos on hand planes and cutting dovetails. Good luck
Troy
Dang it-when is anybody going to understand that the hollow square chisel morticer is designed to be capable of exiting the mortice if necessary without a #@% hole?
It is an old well established machine made in countless numbers found all over the world. Flipping boards certainly excludes the dreaded break outs, but this is not always feasible eg when the mortice is not in the center.And not practical for example in production door making.
It is better to learn how to set up this machine so that it gets the result it was designed to get-which is a clean exit if one needs a through mortice.
Philip Marcou
Philip, I'm afraid you're imputing more capability to a bench-top mortiser than it is due.
If you get clean exit holes more power to you.
There is a way to get perfectly clean mortises when one is required - and that's coming in from both edges (or face) with whatever tool is being used.
This is an indipustable truth.
Edited 8/10/2006 7:53 am ET by BossCrunk
Boss, I'm not disputing anything-I'm merely saying that there is a better way.Entrance door stiles get heavy by the end of the day. And it irritates me when folk are not prepared to properly use a machine that was perfected by cleverer minds.
I've seen it done and that is the way I advocate and use myself-it seems the simplest way to me.Nobody has to do anything he does not want to do.Philip Marcou
I'm with David Pine on the matter, but I'm sure you cut fine mortises.
I enjoy the physical aspect of woodworking, and I doubt I'd expect a benchtop mortiser to do deep entry door mortises all day long, or even to a point that the wood felt heavy to the operator. I imagine the little machine would be in full scream mode at that point.
Edited 8/10/2006 5:39 pm ET by BossCrunk
The machine does not care how big the piece of wood is, all it sees is the part under the chisel.
Since the house is on fire let us warm ourselves. ~Italian Proverb
It cares if the workpiece is wide and it's been running all day or long enough to make the owner tired of flipping the workpiece.
If your 'logic' worked then big commercial doormakers would be using dinky benchtop mortiser instead of one of these 5hp 3-phase 440 volt monsters:
http://www.schmidtindustrial.com/CGI/machines.cgi?action=view&SISID=MO_09_8101
Edited 8/11/2006 10:50 am ET by BossCrunk
Clean your glass belly button boss.
Since the house is on fire let us warm ourselves. ~Italian Proverb
This forum post is now archived. Commenting has been disabled