Can anyone give me advice on how to lay out and fit the support post for the arm on a Chippendale arm chair? The compound curves are confusing. Thanks.
Jay
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Replies
Hi Jay,
Don't know what arm specifically you are working on. Generally, full-size drawings of the arm, seat rail and rear leg (stile) from front and side will yield the needed info and patterns on how the post relates to the armrest and seat rail. I generally work a tenon on the end of the armpost, and lay out the mortise by placing the armrest in its position directly over top the post.
Things like armposts, (and cabriole legs) get laid out on two adjacent sides, and sawn to shape first one side then the other, taping, tacking or otherwise re-attaching the waste pieces from the first side so as to cut the 2d one. For armposts, it is a good idea to cut any rabbets and/or copes to fit around/over the seat rail and its molding before sawing the shape. I've seen old work where the armposts were dovetailed into the seat rail (a vertical sliding dovetail), but most commonly it is notched or rabbetted to fit to the rail and come over any molding on the top of the rail, and screwed fast from the inside of the rail. Typically the arm rest is mortised to fit a tenon cut on the post. Rarely, if ever, a dowel is used on period work at this joint, although it is more forgiving to use a dowel here so as to allow the rest to pivot if need be while dry fitting. The typical attachment at the rear leg is by fitting the end of the arm rest into a shallow (1/8" or so) mortise or recess cut into the face of the rear leg. Sometimes (depending on the design) the armrest wraps around the corner of the leg as well- that is, the end of the rest is notched to fit the outside of the leg, and is captured in the recess at the front. The armrest is held in place usually by a screw angled thru the rear leg into the end of the armrest, and plugged over at the back of the leg. Occasionally I've seen a small bolt used here, with the nut captured in the armrest (buried from the underside) a la bed rail construction. And rarely a tenon is cut at the end of the armrest that fits into a mortise cut into the leg.
I normally glue up the post and rest as a unit, after shaping them individually, except around the area of the joint, which I blend together after assembly. Then I fit the arm unit to the chair. Begin by doing any fitting to the armpost and seat rail, to achieve a nice cope, and to bring the arm rest into a good line-up with the rear leg. Then scribe the leg for its recess and cut it out, sawing and paring the end of the arm rest to accomodate the shape (angle) of the rear leg. When all looks well, drill for the screws, and glue it up.
Drilling for the screw thru the rear leg can be a little nerve wracking the first time. I like to drill a smallish hole first, 3/32" or so, from the inside of the recess thru to the outside of the leg. Then I drill the counterbore for the plug from the outside toward the center of the leg, and finally ream the first hole to the appropriate size for the screw (a # 10 or #12-- as large as the arm can accomodate).
Fitting arms to a chair is a particularly fussy job. It takes longer to do than you will extimate.
Ray
Ray,
I am making a Philadelphia arm chair with carved shells, which is similar to the one Lonnie Bird had on the cover of the American Period Furniture journal (can view as the SAPFM web site). He teaches courses on this and the chair is shown on his web site lonniebird.com He does not sell plans for this chair so I am drafing them myself from photos and drawings in Ron Clarkson's Chippendale chair book. I would appreciate any guidance. If you have built similar chairs, perhaps you have a set of plans that is already drawn that you would share. Here is a general question: When making an arm chair, can you use the dimesions of the usual side chair and just add the arms or is the chair generally wider, with a bigger seat and longer crest rail? Thanks.
Jay
Jay,
I add about 2" to the width of the side chair if adding arms. More if for a big guy :)
Ray
So that means rear rail and front rail of the seat as well as the crest rail are all 2 inches longer and the back is wider. Is that a usual or standard correction, or just something you do personally? To my eye, I would say that seems right. When I started to do the drawing for the arm chair based on the side chair's dimensions, it looked small.
Back to the assembly of the arm, I was hoping to avoid screws. Perhaps incorrectly, I was of the mindset that most old craftsmanship used joinery to attach the arms, either a dovetail into the side of the rear leg, or a tenon into the front of the rear leg. Is there a reason not to do this?
Jay
Jay,
That is the "usual" added width at one of the shops where I used to work. It works out about right. In addition to the front and rear seat rails, crest rail, center and rear stretcher being 2" longer, you'll want to add about 1" to the width of the splat--more or less as the splat relates proportionally to the voids on either side.
I have seen arms attached as you describe, but it is the exception rather than the rule. Given the outward curve of the armrest as it leaves the rear stile (leg), a tenon is located at an area of fairly short grain--a sitter who torques the arms in assisting himself to rise from the seat is at risk of breaking the armrest thru this short grain. The exception is in the early straight-armrest of the William and Mary, Flemish, and Pilgrim era (Brewster, Carver) type chairs.
Given the fussiness of getting the armrest to fit the stile seamlessly, getting the relationship of a fixed, dovetailed armpost and armrest just right is quite a challenge in cutting and fitting, not to mention assembly--it's one of those situations that you can't fit til you put it together, and you can't get it together until it fits. That is, you slip the post in place in its socket, and the arm rest can't slide back into its socket because the tenon on the post is holding it up, til it drops into the mortise. It's a challenge to locate the mortise on the underside of the armrest til you get the fit right at the rear leg (the overall length will be affected by any trimming-- and you can't compensate by moving the post backwards if you've already cut the socket for it in the side rail). The ones I've examined were cut with tapered dovetails and sockets, even so, it is one of those jobs guaranteed to make you cuss, all the more if you are trying to make wages, which is why most of the old work wasn't done so.
Ray
Ray,
When you add the two inches to the width do you also add 2 inches to the depth (ie the side rails) ?
Would you be so kind as to diagram the use and location of the screw(s) to hold the armrest to the rear leg? From your decription I am concerned about that torque you mentioned could rip out a screw, if somone should put their weight on the armrest.
I am not sure I understand how that screw would be used or located. If you actually do this sort of work, you must have used a set of plans, which perhaps you would be willing to share.
Thanks again,
Jay
Hi Jay,
No, I don't change the depth of the seat for armchairs. Nor the height.
It is true that screwed-on arms do sometimes loosen up from being tweaked by older (usually) persons prying themselves out of the seat. However, a stripped-out screw is a lot easier fix, than a split-off tenon. The greater part of the joint's strength comes from the shallow (1/8" or so) housing cut into the surface of the rear leg. The screw keeps the armrest from backing out of this recess, primarily.
Looking down from the top of the chair, the screw is run sort of diagonally out, from the back of the leg, emerging from the leg near the corner of its front and outside surfaces. It enters the armrest and runs an inch or so diagonally into the meatiest part of the armrest's "elbow".
My chairs are built from drawings I make myself, full size. It would be difficult for me to reduce them to computer size, or even to reproduce for you. There are many books available that have decent plans for various chairs, which could be adapted to your specific needs. Nutting's Furniture Treasury, Vol III has several pages devoted to chair plans, and he also discusses therein the attachment of arms. Also Dover publishing has several books with furniture plans. Margon's Furniture Treasures, and Salomonski's Masterpieces of American Furniture are two that come to mind. Also the plans drawn by the late Carlyle Lynch, available at http://www.carlylelynch.com , are superb.
Thanks very mcuh for taking the time to clarify that. I think you said there is also a screw holding the arm support into the side rail.
I am in the process of drawing my own full size plan and will see if I can get hold of some of those references. If the chair is wider and not any deeper doesn't that make the seat look disproportionately wide?
I appreciate the advice.
Jay
Jay,
Usually two screws (one above the other), or three- one above two that are side by side, or vice versa, to attach the post to the side rails. Glue also, this joint gets a good deal of torque. Think of little Muffy climbing up to get on daddy's lap.
Yes the armchair seat is proportionally wider than the side chairs (I think of it as "inviting" :)) ), but if made deeper, the seat can end up too deep for comfort. The front rail will catch the sitter behind the knee.
Ray
Good point about seat depth. I had been concerned about comfort.
As I make my drawing I am having difficulty figuring out how the angles will work so that the cutout at the rear end of the arm has a seamless joint with the rear leg, and simultaneously, the arm support will contact the side rail of the seat. When drawn from above you can make a good pattern for the arm. When drawn from the side you can make a good pattern for the arm support. The problem is that the arm support has to come out fromthe seat just the right amount so the two intersect. To join the curves together of the arm and arm support you have to mortise the supoport into the arm and spokeshav, rasp them together to make continuous flowing lines. Once that assembly is shaped what is your method for cutting it so it fits it to the chair back and seat? Thanks very mcuh.
Jay
Jay,
Heh, heh, heh. Are ye schared, yet, boy??
Well, seriously. Full sized drawings of the seat and rear leg, from the front, side and top, will get you the relationship of those pesky arm parts, to one another, and to the rest of the chair. For instance, the front view lets you draw the post so that at its top, the armrest's "wrist" doesn't overhang the seat. Projecting this onto the top view allows you to draw the armrest so its curves are pleasinbg. The side view, projected onto the top, shows you where the wrist intersects the post- where the arm turns out-, and how far back from the back of the seat the armrest has to project to intersect the backward-leaning rear leg at 9" (or whatever) above seat level.
If you cut the tenon on the end of the armpost, (and at its other end, the rabbet for the seat rail) before cutting it to shape and rounding it up, when you clamp the roughed out post to the seat in its proposed location (as determined from the drawing), you can hold the mostly shaped armrest in nearly its correct position (directly above where it will end up) and trace the location of the tenon on its underside. Once you cut the mortise, glue them together. The resulting assembly can be blended together, then you can put it in place on the chair and fit the end of the armrest to the back leg, ending by scribing around its junction with the leg's face and chopping the recess for it. Sometimes this is a "dado" cut across the whole face, and sometimes (depends on your arm pattern) it is a three sided recess that extends only partway towards the inside corner of the leg's face.
If you have cut a "notch" for the leg at the end of the armrest--on the bandsaw when you cut it to shape-- then that gives you a starting place to hold it to the leg. It will be tight at the bottom, and have a gap of about 1/4- 3/8" at the top of the armrest/ front of the leg, where the leg curves back. You can lay a piece of 1/4-3/8 thick scrap against the face of the leg and scribe along it onto the armrest (top and bottom) to give you a pretty accurate idea of where and at what angle to cut to get a good fit. All this with the arm assembly firmly clamped in place at the seat/post joint. If you have cut a rabbet into the inside face of the post, and coped its top so it snugly fits over any molding on the top of the seat rail, you can simply slide the assembly back along the rail as you remove wood to achieve a fit at the armrest leg joint. Expect to do some paring at the leg, and/ or rabbet planing at the post, to get a glu-able fit.
Easy-peasy. Heh.
Ray
Jay,
To date I have never made a chair with arms, but my dad has made dozens of these essentially exactly like Ray has described.
He used to tell me that you would never believe it but adding arms sometimes doubles the amount of time needed compared to a side chair.
If you are interested, he offers classes on chippendale chairs and chippendale arm chairs a couple of times a year. The location is in Northeastern North Carolina about an hour from the Outer Banks. I'm biased but a week with my Dad will really teach a lot of skills not to mention hard work and lots of fun. My Mom is a great cook, too.
His website is http://www.hobbsfurniture.com and here is a picture of the armchair that his class offers.
Cal
Thanks. That chair appears to be the one drawn by Carlyle Lynch. I have just ordered those plans. I'm sure working with someone experienced like that would be of great value, but unfortunately with demands of work and family I am unable to get away for a week, in the foreseeable future. I will just have to continue to muddle along. I have taken a number of weekend long classes at Highland Woodworking (Formerly Highland Hardware) which have been excellent. The full week deal will have to wait for retirement! Thanks.
Jay
I know what you mean, it's tough for me to get back there myself with all the things going on. I will be there in January and we are working on some pieces together.
The chair is actually a reproduction of an original my Dad owns built in Chowan County, NC in the 1760's(?). It is also shown in the John Bivins book Furniture of Coastal North Carolina. I would call it neat and plain, a little transitional with the crest a holdover of Queen Anne. I'm sure the Lynch drawings are similar as he drew many Southern pieces.
Cal
Phil Lowe sells plans for the kind of chair you're building:http://www.furnituremakingclasses.com/home.html
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