You can make a jig that will cut all three hinge placements , you will need two pieces of 1/2" mdf, the length of the door and no wider than 3" and 6" on the narrow piece at one edge cut the exact cut-outs for the hinges, do be accurate and do it on one edge, place on the door edge, and mark the underside, this will give you a placement to cut a grovve 1/2" wide to inset the other piece of mdf, thus when set it can be placed on the door edge with a downstand against the door side, which you can cramp in place, use a 1/2" top bearing short mortiseing bit, cut out the hinge recesses, open the corners with a chisel and your butts will fit precisely

 

Hi & welcome.
There are 3 types of common hinges. Square corners, 1/4" radius corners, 5/8" radius corners. If your using hinges with 1/4" radius corners then when making your jig (if you decide to go that route) you do not need to radius the corners of your hinge jig. Your jig can have square corners & it will work for square & 1/4" radius. The quickest & easiest are the 1/4" radius because after you mortise them out they are finished. A round 1/2" bit will give a 1/4" radius even with a square corner jig. The square corner hinges require you to square the corners with either a plain chisel or a corner chisel to finish them up.

If you have the 5/8" radius hinges you can use the same template but you would need a 1-1/4" bit or you would have to radius the corners in the template to use the 1/2" bit.

For 18 doors you could also buy a simple template from Templaco. They are around $60.00 for a full size template. They make templates for every part of hanging a door. If you make your own look around their site & it will give you ideas & measurements for your own template. I have the Porter Cable jig & some Templaco jigs. They are very easy to use & very accurate. For their jigs you would use a 1/2" straight bit with a 5/8" template guide or 5/8" bearing guided bit.

Templaco Tools: Router Jigs, Door Tools, Door Lock Installation Kits

Templaco Tools: Router Jigs, Door Tools, Door Lock Installation Kits

 

Hi

Get the jig below, use it for your 18 doors and then sale it off (eBay) you will get most of your money back it's almost renting it but you get the money back and it's almost free for you.. you want a jig that will do it right the 1st. time you don't get a 2nd.chance..

Amazon.com: Porter-Cable 59381 Hinge Butt Template Kit: Home Improvement

http://www.amazon.com/Porter-Cable-...te/product-reviews/B0000224KV/ref=dp_top_cm_cr_acr_txt?ie=UTF8&showViewpoints=1
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