Do Frames Have To Have a Base Cure?

[R.Mack]

Hello to all,
My name is Ron, and I'm in the process of making a pair of eyeglass frames from wood. I would like to know if a base curve is absolutely necessary for frames, or could they be flat? I haven't figured out how to bend the base curve in the wood yet, because I laminated the wood, so steam bending is out of the question. I'm open to suggestions on how to bend the frames too, thanks.

[shanbaum]

Whether an eyewire needs to be curved depends on the shape. A circle - a round shape - wouldn't need to be curved. Truncate that circle, and the truncated element will need to be curved (unless, of course, the bevel is not curved). Imagine truncating a curved, round lens top and bottom. Of course, most frames are not round. And unless the frame you're making ends up being very pliable, the frame curve and bevel curve will need to match very closely, otherwise you'll have a really hard time inserting lenses, and if you succeed, the lenses will probably get deformed to the extent of the mismatch (they'll likely be more pliable than the frame).

[R.Mack]

Hi Shanbaum,
Thank you for replying. The lens shape is not round but closer to rectangular (not actually rectangul). Some of the information you provided is a little over my head but I will give myself some time to digest it. I have noticed that when i see people wearing round sunglasses simular to the ones that John Lennon use to wear they have no base curve in the frame.

Thanks,
Ron

[MikeAurelius]

The short answer is that yes, if the lens opening is not circular, it will need to have a curve in it. However, a steam bender is not that hard to fabricate. It can be done quite easily especially on small pieces of laminated wood.

[R.Mack]

The short answer is that yes, if the lens opening is not circular, it will need to have a curve in it. However, a steam bender is not that hard to fabricate. It can be done quite easily especially on small pieces of laminated wood.

Hi Mike,

Thanks for your reply. Have you made wood eyeglass frames before? if so, would you mind explaining your process? How did you make your steam bender?

Thanks,
Ron

[MikeAurelius]

I've not made eyeglass frames, but I do do a fair amount of woodworking.

Here's a link to get you started: http://robroy.dyndns.info/baidarka/bending.html

However, as I thought about it over the weekend, you may want to take a different look at it.

Part of the beauty of laminating wood is the different edge colors you get from different wood types and grain lines.

What you might want to consider doing is laminating several types of wood face-to-face to achieve a "blank" about 1/2" thick. You will need to use a transparent waterproof glue as well. Clamp well during the drying process, and allow the glue to cure for several days before unclamping.

Using a jig saw, cut a rough opening in each blank to approximate the lens opening you desire. Using a router with a straight flute cutter, finalize the the shape. Then cut the outer edge of each blank to the final shape you want for each eyewire.

Then, with a bench mounted belt sander, begin to shape the blanks with a right to left curve, convex side towards the front of the blank, and match the curve on the back of the blank with a concave surface. You are ultimately going to want approximately a 125 mm radius (5") - this will approximate a standard spectacle frame base curve of 4 diopters.

The eyewire should finish about 3/16" thick when you get it done. Use a fine sandpaper, 220 grit, and hand sand the pieces, paying attention to the edges, being sure to round them off and removing any burn marks from the router. Apply some sanding sealer, then sand again with 220 grit.

You will need to put a 60 degree angle Vee cut on the inside of the eyewire to retain the lens. Use a router bit with a bearing guide so you can follow the inside edge of the cut out and not gouge out any wood. Sand, seal, and sand again.

Your final coats should be multiple coats of clear spar varnish designed for outside use.

Good Luck and have fun!

Be sure to post picture of the finished frames!!

[R.Mack]

I've not made eyeglass frames, but I do do a fair amount of woodworking.

Here's a link to get you started: http://robroy.dyndns.info/baidarka/bending.html

However, as I thought about it over the weekend, you may want to take a different look at it.

Part of the beauty of laminating wood is the different edge colors you get from different wood types and grain lines.

What you might want to consider doing is laminating several types of wood face-to-face to achieve a "blank" about 1/2" thick. You will need to use a transparent waterproof glue as well. Clamp well during the drying process, and allow the glue to cure for several days before unclamping.

Using a jig saw, cut a rough opening in each blank to approximate the lens opening you desire. Using a router with a straight flute cutter, finalize the the shape. Then cut the outer edge of each blank to the final shape you want for each eyewire.

Then, with a bench mounted belt sander, begin to shape the blanks with a right to left curve, convex side towards the front of the blank, and match the curve on the back of the blank with a concave surface. You are ultimately going to want approximately a 125 mm radius (5") - this will approximate a standard spectacle frame base curve of 4 diopters.

The eyewire should finish about 3/16" thick when you get it done. Use a fine sandpaper, 220 grit, and hand sand the pieces, paying attention to the edges, being sure to round them off and removing any burn marks from the router. Apply some sanding sealer, then sand again with 220 grit.

You will need to put a 60 degree angle Vee cut on the inside of the eyewire to retain the lens. Use a router bit with a bearing guide so you can follow the inside edge of the cut out and not gouge out any wood. Sand, seal, and sand again.

Your final coats should be multiple coats of clear spar varnish designed for outside use.

Good Luck and have fun!

Be sure to post picture of the finished frames!!

Thanks Mike for taking the time to post the tutorial, I appreciate it.

Question: What clear waterproof glue do you recommend, and can the glue withstand steam when bending the frame?
If I successfully complete a pair I certainly will post a picture.

[idispense]

An alternate method, although it may not expose as many color and grain variations, is to laminate the pieces against a mold or form of the required base curve. You can do this with matched top and bottom molds or forms or using a single form.

This video shows the technique on a large item using a vacuum bag as the clamping source, but you can clamp manually if you like.


http://woodtreks.com/how-to-laminate...e-plywood/842/

This video shows the technique using small strips and male and female matched forms.

http://www.rockler.com/how-to/bendin...nt-lamination/

[R.Mack]

Hi Idispense,
That was an interesting read. Thanks for posting.