Child's Building Blocks -- Roman Arches & Half Arches

[Don from Maine]

Help!! I've started making a nice set of unit building blocks for my niece and grandson out of 6/4 walnut and cherry. The unit block size is 1-3/8 inches by 2-3/4 inches by 5-1/2 inches and all my other blocks will be multiples of it. I want to make some of the Roman arches and half arches out of a unit block. The problem I have is that I don't know how to make each of them look exactly like the other. Has anyone designed a jig which can be used on a band saw or with a router to cut these shapes out? I want to make about 10 of each. Thanks.

[Mike in Mystic]

I would set up a sacrificial fence on your drill press and use large fortsner or saw-tooth bits to cut half-circles. Use a stop block and you'll get identical parts. You could also make the parts twice as wide as needed and drill a circle centered across the width and then just rip the part in half on the table saw.

Mike

[Robert Bonomi]

A roman arch is a simple half-circle above the opening.

A 'gothic' arch has arcs that are the full width of the opening

the 'easiest way to get roman arches, is with the proper size drum on a spindle sander. Ditto if you're making blocks with a quarter-circle 'bite' out of one corner.

Saw on the 'waste' side of the arch line, Clamp a couple of stop-blocks to the sander table, And then 'introduce' the block to the sander, until it hits both stops.

Voila!

[Don from Maine]

Thank you all for your input! I'll give the ideas a try and see how it goes. Thanks again for your help, the kids should love the blocks and I'm glad there are still people out there in this high tech world willing to give others a hand :-)

Happy Holidays!, Don