Project with an arch ... Help me calculate it

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I took on building a front entrance enclosure with a gate and artwork ... I know the width and the height to the tallest point ... The customer is 2.5hrs away ... I'm thinking I know this but input would be appreciated.If I determine the exact height of the point of the beginning of the arch on both sides ... then a straight line from side to side ... find dead center and from there use a string to the highest point then draw the arch. Would you trust the homeowners tape measure? Or do I need to take the drive and do my own measurements?What say you ...Located In SE OklahomaLincoln Mig 135Hobart Ironman 230 Mig5x10 CNC Table with DTHC & FTHypertherm PM65 on the tableMiller Bobcatwww.caneyagequipment.com
Reply:I would lay out the measurements given to you on a piece of cardboard, then cut it very exactingly to those measurements.  Or, cut to the final measurements you need relative to the measurements they gave you.  Load that template (and any others for this job) into your vehicle, looks like you'll also want a ladder, then take a road trip and be double-darned sure that what you're making will fit.  Hate to spend a lot of time doing something then find the original structure is off square / off radius.That's just my opinion.
Reply:Arch looks like it starts lower than your line to me. If you draw a 1/2 circle ( what I assume you are referring to as an "arch", the ends at the horizontal are vertical. Your mark looks like it's at a point that is an angle, telling me either, the arch isn't a true 1/2 circle, or your start point is too high.Many times, depending on how the framer made this "arch", the arch itself may not even be symmetrical side top side. I've seen plenty where if you make a template one way, then flip it over, it will not fit.All this may or may not matter, depending on how tight you fit your work to the existing structure. If it is going to fit tight, then I'd take my own measurements and template it. If you have a reasonable fudge factor since it will not be tight, you have more tolerance if things aren't perfect..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:No way I would do anything without field measuring. I would bring ladders and help to make a full size template of that arch from a level line as well as height measurements down from the line to the base. Also check the width at top (template), middle and base along with any out of plumb or bow conditions on the sides. I would also want investigate what's needed to install and get a good anchor to  the frame. Looks like that stucco could be on Styrofoam. The cost of the field measuring should be included in the estimate along with design, materials, labor, install and any other expenses. I require deposits and balance upon installation.
Reply:I'd take your own measurementsPlus I like that cardboard commentClamp or tape up cardboard, or some sort of trashy cheap light plywood and physically trace it out.
Reply:I would have to make the drive and make a template onsite. Just because it looks like am arch doesn't mean that it is perfect to start with. Mike
Reply:I agree with metalman21.Field measure and make templates. 99.9% chance it's not a consistent radius and just doing the math for a chord and girth measurements won't cut it.I had a similar job in Manhattan Beach, CA (about an hour away from my shop). I did field measurements and made a 3D template from 1/4" bender board and some 1x2 boards to lock in the shape of the turret on the front of a house. Had I relied on just the math I would have scrapped the custom copper and iron planter that I built.Using the template I had made the final install took about an hour and the planter fit like a glove.
Reply:Originally Posted by tbone550Hate to spend a lot of time doing something then find the original structure is off square / off radius.That's just my opinion.
Reply:So far the quote has been accepted ... deposit is pending Via credit card. Once thats approved I'm gonna load up and go take ya'll's advise. For some reason I knew the answer to my own question. Was just hoping someone had that "magical" answer ....so many factors all of which have been mentioned.Located In SE OklahomaLincoln Mig 135Hobart Ironman 230 Mig5x10 CNC Table with DTHC & FTHypertherm PM65 on the tableMiller Bobcatwww.caneyagequipment.com
Reply:Just check and the down payment has been paid via Credit Card ... I'm in business and south bound sometime this week end to get the measurements!!Located In SE OklahomaLincoln Mig 135Hobart Ironman 230 Mig5x10 CNC Table with DTHC & FTHypertherm PM65 on the tableMiller Bobcatwww.caneyagequipment.com
Reply:I'd bring along a sheet of Masonite or door skin with you and also it up there and trace the arch. Like ZT said above, I doubt that's a consistent radius. With a template you'll be guaranteed a good fit.
Reply:Frame it on site out of metal.  Brace it well for transport.
Reply:Originally Posted by Sharon NeedlesI'd bring along a sheet of Masonite or door skin with you and also it up there and trace the arch. Like ZT said above, I doubt that's a consistent radius. With a template you'll be guaranteed a good fit.
Reply:I would be inclined to for template and frame.  Typically template is the way I go. However,  if I am driving 2.5 hrs.  Why not frame at least the arch. Also my nemesis is fitting items between columns or inside fixtures.
Reply:I'm thinking that I'll use 1.5" by 1.5" 14 ga for the framing ... roll the tube to fit the arch .. frame the door/gate in with jams and header out of the same tube. Use self closing hinges. I'll cover the frame with 14 ga sheet with the artwork in it.... Horse's, Texas Star, the family name and incorporate flowers and vines.Located In SE OklahomaLincoln Mig 135Hobart Ironman 230 Mig5x10 CNC Table with DTHC & FTHypertherm PM65 on the tableMiller Bobcatwww.caneyagequipment.com
Reply:Why not flat bar  for framing.  1.5" sq is 3" taken up.  Seems like thick metal competing with the nice architecture already present.  More gate less frame.  I'd loose sleep and some money(lack of designing  redesigning fee) over the best way to design without disrupting/compete  the nice appearance of the house.
Reply:Originally Posted by tapwelderWhy not flat bar  for framing.  1.5" sq is 3" taken up.  Seems like thick metal competing with the nice architecture already present.  More gate less frame.  I'd loose sleep and some money(lack of designing  redesigning fee) over the best way to design without disrupting/compete  the nice appearance of the house.
Reply:I agree with all the above about the on site work. A carpenter would use a compass and mark the existing edge around any complex shape... then it's all hand & eye to keep the gaps looking right.If it doesn't look right - then it's not right...Matt
Reply:Originally Posted by tapwelderFrame it on site out of metal.  Brace it well for transport.
Reply:ZTFab....that's some beautiful work!I made patterns on site from 1/4" plywood for some projects last summer:SS curtain rod for a round room apx. 12' diameter:Had to make the brackets, nothing ready made would work:Everything had to fit and finish match existing glass finials:Room was not a perfect circle, the wood patterns were three 8' sections screwed together and reassembled in the shop.
Reply:If I went with the carpenter's pattern I would have scrapped the brass tubing for the bar foot rail.I made hard patterns first from cardboard then fiber board so the glass shelfs would fit.
Reply:Man thats some awesome work ... Thanks for sharing.Located In SE OklahomaLincoln Mig 135Hobart Ironman 230 Mig5x10 CNC Table with DTHC & FTHypertherm PM65 on the tableMiller Bobcatwww.caneyagequipment.com