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I’m installing crown molding on the exterior of a house with a 10/12 pitch roof. I can’t seem to get the miters right expesaly were the gables return and follow the eves. I have kind or figured it out with a lot of tyral and error, but there not perfect and I have to know why my miter saw setting are where they are. Any suggestions on what angles to use and a explanation on why would be helpful!
Thanks alot!
Chris
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Do a search in the archives. A zillion posts about Oct or Nov of last year. Or sit tight and wait for the mathemeticians to decend. If you're good with numbers and can understand the printed word, you'll get your answer. Best of luck.
I've had occasion to do this once and it was a humbling experience. I too thought (and I guess there is) there was a solution. I used the trial/error method and wrote down all the numbers of the cuts etc. I did it and it was painted and it was a two story but it did look good from the pick cuz I'm picky. But it almost seemed impossible. There was a little whittling and shaping to get it right.
The jist of the story is, I guess it takes two sets of mldg with the same profile only one is bigger than the other. So the profile isn't exactly the same. They had it figured out that one had to be .4998022074 or something wider so that when the two planes, hori. to running up the rake converged, the shape of the mldgs would line up.
So, if you got the time and the two sets of mldg, do it the right way. If not, make it look good and go to the next one.
Best of luck again.
*One thread Calvin is referring you to is i "exterior crown molding angle between rake and eave" posed by "bill ritchie"I didn't contribute to that thread but I did lurk and enjoyed the fireworks. Look out for references to books by Ernest Joyce and George Ellis, something like post 40 odd. I think there are some explanatory drawings from Joyce or Ellis posted too. If I've read your question correctly, the graphics I'm referring to probably provide a solution. This solution works for us furniture makers anyway, so I suspect that with a bit of thought to adapt to your situation, it will work on a house too. Ken Drake "exterior crown molding angle between rake and eave" 11/25/99 8:19pmSliante.
*Sgian Dubh,
View Image © 1999-2000"The first step towards vice is to shroud innocent actions in mystery, and whoever likes to conceal something sooner or later has reason to conceal it." Aristotle
*Chris,Do you have a scanner?If you do, take a small piece of the crown mold that is running along the eaves and trace the profile ( square cut, no bevel ). Scan it and post it.Also, are you using "standard" crown mold that lies 38 degrees away from plumb? If not, what is the angle away from plumb along the eaves? 45 degrees? other?If you have already run most of the crown mold along the eaves, for a 10/12 pitch, you'll need to have a different profile for the rake mold at the gable ends.It's possible to use a single profile to accomplish the job, but you have to radically alter the angle away from plumb for both the eave mold as well as the rake mold.I have some free time tomorrow, and will watch for any post from you.And believe me, I won't be alone!
*Lock and Load
*Thanks Joe for putting up the correct link for me. I can't do those blue underlined link deals at all, and I was surprised when it popped up as it did in my first message. I simply highlighted the gobbledygook in the address from that old thread, copied it and pasted it into my response to the question. I expected it show up as gobbledegook too, but it didn't. Sliante.
*Sgian Dubh,
View Image © 1999-2000"The first step towards vice is to shroud innocent actions in mystery, and whoever likes to conceal something sooner or later has reason to conceal it." Aristotle
*Chris,
Click to enlarge image.
Click image to enlarge. Click image to enlarge. Click image to enlarge. These pictures show all the relationships between the two crowns. The next group of pictures show the two crowns joined. Click image to enlarge. Click image to enlarge. Click image to enlarge. View Image © 1999-2000"The first step towards vice is to shroud innocent actions in mystery, and whoever likes to conceal something sooner or later has reason to conceal it." Aristotle
*Many thanks for the kind words regarding my work. Talking about oddball mouldings going together, Dresser 5 has an interesting cornice or crown problem too. (If anyone is wondering what I'm on about, a bit of clicking will find my website easily enough.) In that piece (Dresser 5) two mouldings of different profiles were mitred together to form the cornice. *The front moulding is square in section (basically a plank with some decorative detail hacked out at the top.) and sits vertically on one edge. *The two side return mouldings are dished or coved on the outside face, but the top and bottom edge, and back face are square to one another. *The intersecting corner mitre between these dissimilar sections is therefore a very complex compound curve on the end of both pieces that has to be carved by hand, and I did it very neatly too, if I say so myself!Don't ask me how I know how to do it, I just know, and that's all that matters to me. Frankly, I consider my knowledge of geometry, trigonometry and other maths as woeful, but I do know how to calculate dihedral angles for polyhedra, calculate ellipses, chords of circles and so on to get me through the furniture making processes I need. I suspect that a lot of what I do is 'instinctive' for want of a better word, and is a reflection on my formal training as a cabinetmaker. There are many things I can demonstrate that I can't explain in words on paper, I just do it.I was hesitant to offer the Ellis or Joyce method (which I i have used[many moons ago I grant] in raking furniture mouldings) as a solution to the problem posed here for I'm not au fait with American house joinery or carpentry. Instinctively I feel that because most American architectural mouldings are 'sprung' from the walls, and have back angles of what(?) 52/38 degrees complicates matters. In most (European) furniture- i my specific field of experience, requiring complex cornices with breaks, returns, and rakes for instance, the back of the mouldings were, and are usually made square, often with cheap deal or pine as the ground, and expensive show timber used for the profile is therefore saved by being glued on as required. (Charles H Hayward is a good source of information on this topic, along with the other authors already mentioned.) It just seems to me that having the back of the mouldings square, and the particular application being furniture, the solving of many of these problems becomes somewhat easier for there isn't any dead triangular space at the back caused by the 'spring.' Hopefully I've made myself clear regarding my first contribution in this thread where I suggested a solution might be found by adapting the techniques illustrated by both Joyce and Ellis. Of course, I could just be opening my mouth and letting my belly rumble, but I'd like to think that that's not entirely the case! I too have sniffed around your website, and there is a bunch of excellent information in there. I'm impressed. Sliante.
*Joe, Where can I learn to do all the technical magic you do with the computer? It would be nice to be able to do even half the stuff you're doing with the computer. I spent 22 years learning to be good at construction, now I feel like I'm starting all over again learning computer-eze.
*It's not all that bad -- just learn a few basics about HTML, the "language" that tells the browser what to put where, like a photo album. No magic, and not even close to real programming.Re moldings, I agree with Ken and Calvin. Really, you need two widths of the same profile.
*Andrew,If Chris has already run the eave mold at a 38 or 45 degree spring angle ( the angle away from plumb ),he'll definitely need a different "stretched out" profile for the rake mold. No matter what combination of angles and bevels he chooses, the same profile just won't work. One of the reasons I asked Chris to scan the profile of the crown molding that he is using and post it, was to see if it was a "standard" type molding, often available in different widths. If it were, he might be able to purchase a few pieces of the NEXT LARGER WIDTH and "get it to work". It wouldn't be a perfect fit, but with a little sanding and chisleing, it might look okay.
*Bill,
View Image © 1999-2000"The first step towards vice is to shroud innocent actions in mystery, and whoever likes to conceal something sooner or later has reason to conceal it." Aristotle
*Actually I was serious in my comments and question. I am very interested in learning, I have admired your ability for some time, and I would like suggestions on what/how to start gaining this knowledge. Everything I now do with a computer, I basically learned on my own. Now I would like to learn more without all the trial and error. I also plan to set up my own company web site in the near future. Any help is appreciated.Sorry to get off topic here.
*Bill,
View Image © 1999-2000"The first step towards vice is to shroud innocent actions in mystery, and whoever likes to conceal something sooner or later has reason to conceal it." Aristotle
*Good point, I'll start a new topic.
*Actually, I agreed with you, I think. I wouldn't call the larger moulding "stretched out" -- it's just a larger projection of the same geometric profile in BOTH dimensions. Unfortunately, the mills don't always make the different size mouldings with precisely the same profile.Personally, I like "RAKE moulding" better anyway. Perspective-wise, it is just more appropriate -- and it's what our house started out with before the advent of aluminum siding concealed it. Consider the angle you'll be looking up at it from ... and that NO ONE else will ever notice it (except the occasional Breaktime passer-by).
*Well, Joe, to call you an idiot would be unduly flattering, but yes I do have extensive experience with C, and not as a hobby. Can't resist a mindless swipe, can you? HTML is a cakewalk by comparison ... but perhaps not for you. :) There are many graphical editors (MS Frontpage etc.) that spare one from hacking the actual code ...Perhaps while you were "writing" in it, you might have noticed that the language is actually called FORTRAN (Formula Translation). If you're going to make things up, at least look them up first. Kudos, you did spell "C" correctly.
*Joe, you seem to have a formula for every situation. Are you a math savant, or do you have a few good reference books of the compiled info? If it's books, which ones? I, too, like to break things into formulas, but it tough to retain everything from H.S.! I learned roof framing using formulas and a scientific calculator, had a teacher that wanted us to know how to use a framing square, and know why it worked and where the info on a square came from. Let me know if you have a good source(printed) of formulas. Thanks, Jeff
*Barrister,
View Image © 1999-2000"The first step towards vice is to shroud innocent actions in mystery, and whoever likes to conceal something sooner or later has reason to conceal it." Aristotle
*Jeff,
View Image © 1999-2000"The first step towards vice is to shroud innocent actions in mystery, and whoever likes to conceal something sooner or later has reason to conceal it." Aristotle
*Well, for the interested, HTML is more like Postscript, a page description language used in digital publishing, than like the many procedural languages used to write applications and the like. HTML tells your computer where to put the pictures and text, roughly how big to make them, what functions or page links to assign to clicks in different objects, etc. Java and Javascript (similarly named but unrelated), by contrast, can tell your computer to do fancier interactive things. There is a self-modifying interactive HTML, but enough said already.Not sure why Joe brought this up -- I guess it's been eating at him. Like so much in life.
*Another polluted thread.Let's see, what was the original topic? Angles, bevels, and profiles? Or was that egos?Take it to bed.Your little ongoing banter is getting old, and I don't think I'm speaking just for myself.Forgot how to use e-mail?
*Ah, Ken, you were mud-splattered yourself last time. Clearly silence is golden, but always letting the last word pass gets old...Anyway, is the poster's question answered? Chris??Neat tidbit: Someone related last time this came up that it the good old days, when moulding were planed on-site, the carpenters had a "standard" (regionally) pair of knives to cut matching rake and eave mouldings -- so no geometry involved. A given planer pair would work for only one roof pitch -- plus some room for fudging one way or the other, and of course a lot of tweaking went on.I'd love to learn more on the practical and aesthetic development on mouldings. For example, there was a TOH article last year that discussed briefly the evolution of window muntins as glass technology and tastes changed. Blessedly, they stopped short of today's era of clip-ons.Anyone know of some inexpensive 3D surface or even wire-frame modeling software for the Mac?
*I can respond to bits of your question, and three books might be worth your while taking a squint at,* Charles H Hayward, Antique or Fake, 0 7135 2356 5. * George Ellis, Modern Practical Joinery, 0 85442 039 8.* Ernest Joyce, The Technique (US Dictionary) of Furniture Making, UK ISBN 0 7134 0217 2. In the US I think it's 0 8069 6440 5.The first book might be out of print, is furniture specific (as are the other two) and furniture mouldings reflect styles of architectural mouldings. George Ellis is a superb book, about 100 years old and will knock your socks off regarding technical problem solving. Joyce is regarded generally as the furniture makers Bible in the UK; packed with all sorts of nuggets. Okay, this stuff isn't house building, and I indicated earlier in this thread that I execute the intersection of raking and horizontal mouldings, along with other oddball stuff, but we (European furniture makers anyway) use mouldings that are square in section at the back face, and the top and bottom edges. I don't do calculations (as exampled by others) to determine, *1. the width and profile of the raking moulding relative to the horizontal moulding, because each is a draughted development of the other (and a cutter can usually be ground specifically for a job in about two hours) and, *2. the necessary bevel cuts to form a mitre at the intersection is again determined by using either draughting techniques- or sometimes simply by holding one moulding on one face, the other on the other face (at the appropriate angles) and determining the bevel cuts by making and transferring marks using a bevel gauge, and a pencil.These techniques are very clearly, but densely described in Ellis, Chapter XXII, P. 365 to P. 385. Some illustrations from this book are posted in the earlier thread referred to earlier in this topic. These are the methods that I was taught and work well for me, but as before, my furniture making methods don't necessarily apply to the house builder.Can't help you with any of the other stuff, I'm afraid. However, I noted your use of the word muntin, and in the European cabinetmaking tradition that I'm most familiar with there is a distinct difference between a muntin and a mullion. The first is a vertical division between rails in timber panelled frames, and the second is a vertical sash between glass panels. I find it interesting that different cultures modify the specific meaning of a word to suit local usage.Sliante.
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I'm installing crown molding on the exterior of a house with a 10/12 pitch roof. I can't seem to get the miters right expesaly were the gables return and follow the eves. I have kind or figured it out with a lot of tyral and error, but there not perfect and I have to know why my miter saw setting are where they are. Any suggestions on what angles to use and a explanation on why would be helpful!
Thanks alot!
Chris
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Dear Chris, I just did a bathroom ceiling with a lot of angles, valted and angles. All I have is a 12 inch chop saw, I treated the ceiling as the 2 planes, of
cathedgral ceiling.
I cut the crown as though I was only concered with the angle of the ceiling, and not changing the pitch or twist of the lower peice of crown, which ran
horizontally.
I always cut my crown while holding it at the profile it will be installed at
(ie. crown stops or penciled line on box) Then I only have to deal with bisecting the
angles of the intersecting walls.
If you hold two scraps of crown cut at a 45 degree angle that you would have cut
for a standard wall ceiling application, this would also fit your overhang.
This will work, on your bottom drip edge and rake cuts.
When you are cutting your plum cuts for the top of your gable, lay your crown in
box right side up, instead of upside down (like you did for previous) and cut at 40 degrees, which is 10/12