cutting to fit an archway

[js5895]

Hi,

I need to cut a piece of wood to fit in a brick archway. How to I find the curve to make it fit perfectly in the archway? It is 35" wide and the center of it curves inward 3" high.

Thanks.

[Wood Butcher]

Make a cardboard template.

Art

[js5895]

How exactly do you do that?

[Rumpy]

Hold the cardboard up to the brick, and trace the opening with a pencil or pen onto the cardboard, then take the cardboard down and cut it along the line you traced. Check the fit of the cardboard template by holding it back up to the brick and trim as needed. Once you are happy with the template, trace it onto the board and cut the board along the line you traced.

[js5895]

If you mean take a piece of cardboard and place it over the archway then, I can't, because the ceiling is in the way of it, blocking it completely.

[Wood Butcher]

Cut the cardboard so it's close to the desired shape. Hold it in place and scribe it to fit. Cut it on the scribe line. This should get it near perfect. If not, tweak it 'till you're happy with it then use it as a template.

Art

[Jody]

Get you a strip of hardwood say 1/8" thick by 5 or so feet. Tie a string to one end. Now loop it around the other end and form a bow. Put it in the arc and let it spring fit to your opening. Tie off the sting so the bow will not spring back when removed. Mark the center of the bow from the center of the arc. Do the same with the ends. All you do then is lay it on your wood and trace.

[Dhakala]

Elegant solution, Jody!

[Lew Hodgett]

RE: Subject

Hire someone who is competant to do the job.

It will be less expensive in the long run.

Lew

[bridger]

but unlikely to make more than an approximation of the curve.

[Guess who]

That's the only way to do it, and at the same time to nicely avoid one of those endless discussions on how to find the radius from a perfect arc.

[Rumpy]

Well now, you failed to mention that, didn't you. Perhaps you should be a little more specific with your questions. If all you ask is 'how do I cut a piece of wood', don't be surprised when all of the responses are 'with a saw'.

[js5895]

"Hire someone who is competant to do the job." I've had city workers, power company people, carpenters, electricians, plumbers, and all of them botched the work, I'm more competent then they were.

Rumpy, how can I get any more specific, all I need is to cut a piece of wood to fit inside of a brick archway.

Lew, your calling me incompetent when you didn't even spell it correctly.

[Upscale]

Might I suggest that if "you're" going to correct someone's spelling, you don't make worse any errors yourself.

[Lawrence Wasserman]

Look up "scribing" to fit and you'll get some ideas on how to do this.

[Rumpy]

Great, then trace it and cut it. Not being able to get a pencil in to trace it is an important detail that you left out. Peoples answers will only be as good as the question you post. I'm not trying to rude, I'm just saying a picture or a better description would help. The way the original question was stated, it sounded like a no brainer, just trace it.

Given what we now know, it is going to be a little more difficult than that. How tight do you want the fit? Do you intend to actually perfectly match the brick with protrusions on the wood to fit tight against the mortar joints, or are you just trying to get the basic shape? Given the nature of brick, I would be willing to bet a cheese burger that the arch is not perfectly circular or parabolic or any thing else that could easily be reproduced mathematically, so one way or the other, you will need a template. As someone else has suggested, roughly cutting a piece of cardboard to fit the opening, then scribing an exact cut line onto might be the way to go. Another idea might be to buy a large flexible drawing curve, (one of those plastic coated wire things), and bend it to match the contour, then trace it. For that matter, maybe just a piece of wire would do.

Not sure if this is large enough, but it's the type of thing I'm thinking of:

are a few scribes while I'm at it: ?familyid=5056

[js5895]

Rumpy, I know I'm not going to get a perfect fit, there's going to be gaps, as specially because it's an old house. I just thought instead of always scribing, there was a mathematical approach, thanks.

Upscale, at least my sentences make sense. "you don't make worse any errors yourself"

;)

[bridger]

there are some mathematical approaches that make sense in various situations. some of them could be described as advanced scribing techniques.

for your situation and what I percieve to be your skill level, the snipping away at a piece of cardboard approach is effective and straightforward.

[Upscale]

When editing it, I neglected to remove either worse or any. And you did understand what I was saying even though I left the sentence uncorrected. Better be prepared to get criticised for those things that you criticise others on or you're not going to do too well here.

[Rumpy]

Well, ok, if it is truly circular, and you have a 3" segment rise over a 35" chord length, the radius of the curve is close enough to 52-1/2". I suppose you could either use a circle cutting jig on a router or a string and pencil to draw it. Either way, if it's not close enough, post more accurate measurements and I, or some one, will find the radius for you. (I will be out of town all of next week, fwiw).

BTW, I admit I cheated and drew it in AutoCAD. Not long ago there was a bit of discussion here on how to calculate. Maybe some one else will re-post it.