I was listening to the Shop Talk Live 294 which I really enjoyed, even though I don’t plan on building chairs. One of the “chair geeks” talked about teaching students when to add a stretcher if the leg spindle was a certain length or thickness. I can sketch an item I want to build that looks good to my eye, but I don’t know that it will even hold its own weight.
Can someone recommend books or magazine articles etc.
I greatly appreciate it. Thanks.
Ken
Replies
No help here, but thanks for asking. I’ll be watching for responses from those in-the-know. Sometimes I have ideas for projects but then it goes nowhere because I don’t know even the basic rules of structural design. Example: a hallway bench for putting shoes on and taking them off. Looking for examples online I saw one (probably Wayfair or Walmart or some such) that looked kind of like what I was after, but it didn’t have stretchers. It looked like it would rack badly under “normal” use, and eventually crumble. Do you always need stretchers for a heavy use bench, or are aprons enough, and if so how wide do they have to be? (These are rhetorical questions).
I think you would be hard pressed to find a reference book that dealt specifically with that (stretchers e.g.) - in a way that covered the gamut of styles. One thing that is critical - is the design/style - and you haven't noted that. . That said, one "approach" is to look at various historical models that have lasted through the "centuries" (or less). What was the design used? You could do this easily by looking at websites of museums that have substantial furniture collections. MetMuseum, Boston MFA, Wadsworth Athenaeum a few in the U.S. Additionally, drawings can be found which can be very instructive - Roubo or Diderot for French models, drawings of Chippendale's work - for standard European. Colonial U.S. books available. Lastly, and perhaps most importantly, seat furniture always gets prototyped.
I was thinking about this last night and came to this conclusion. If I would just be more observant of structural details in (good) furniture that I see, I’ll pick a lot up over time. When I see a piece I think of the aesthetics, I need to train my eye/brain to focus on how it’s constructed. Unfortunately my powers of observation absolutely suck. Need to work on that (sigh).
That's a really broad question. Books have been written on it. Thicknesses of the pieces, length, species of wood, straightness of grain. If it's chairs you're interested in, check out Chris Schwarz's Stick Chair book.
Not much help here on chairs, but here a reference to the bookshelf 'Sagulator'. Seems to still be an active website.
Engineer Shelves With The Sagulator
Online calculator determines thickness and length to prevent shelves from sagging
By Bill Kovalick #190–Mar/April 2007 Issue
https://www.finewoodworking.com/2007/01/05/engineer-shelves-with-the-sagulator?oly_enc_id=9129H0648890I2D
https://woodbin.com/calcs/sagulator/
Thanks for the responses. I actually have no desire to build chairs, the topic just came from the podcast with chair builders.
This question came up while designing an end table. Is the apron enough or are stretchers needed also. or instead of?
@elmaduro: Thanks for the link to the article on the Sagulator because it led to links
https://www.finewoodworking.com/2015/05/27/build-lighter-stronger-furniture
https://www.finewoodworking.com/2018/05/30/strategies-building-stronger-furniture
There must be a "rule of thumb" that says if an apron is a certain length, the width of the apron needs to be x or a % of the length. Maybe there is no such thing. Copying someone else's design is fine, but what if the dimensions used are simply what the builder had on hand at the time and not related to structure?
Just food for thought. I hope we get others to chime in as well.
Thanks
Ken