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Make a Solar Cooking Frame for Cheap (Fresnel Lens Frame)

00:00:06I’m getting a couple of wood

00:00:09two-by-fours ready because my 4-foot

00:00:11magnifying lens needs a sturdy frame i

00:00:13hack this out of an old TV in a previous

00:00:15video but it’s too flimsy to use on its

00:00:17own we need something that’s super cheap

00:00:19to make but sturdy and easy to use and

00:00:22I’ve got an idea that just might work


00:00:39measuring the size of the lens seems

00:00:41like a good place to start so let’s do

00:00:43that and then mark the wood for custom

00:00:45cutting it’s best to use as little wood

00:00:47as possible so I’m going to use this

00:00:49table saw to rip these studs into this

00:00:51shouldn’t compromise the integrity of

00:00:52the frame at all and it will cut the

00:00:54weight in half these two by fours are

00:00:56now two by twos and will need to cut a

00:00:58group right down the middle once I’ve

00:01:00got the centre lined up I’ll lower the

00:01:02blade down to about three-quarters of an


00:01:04and get the saw spinning as the beam

00:01:06glides over the blade I’m happy to see

00:01:08that it cut the clean 3/16 inch groove

00:01:10this is the groove that our lens will

00:01:12fit into and sliding the pieces together

00:01:14into place proves that the cuts were

00:01:15good the edges match up and the frame

00:01:18looks functional but before we secure it

00:01:20we’ll need to drill some holes right in

00:01:22the center to accommodate this three

00:01:23inch bolt I’ve added a rubber washer to

00:01:25the bolt and pushed it through the hole

00:01:27then when this piece goes back in place

00:01:29we can still access the threads whoops I

00:01:31almost forgot I wanted to add a more

00:01:33finished look to this frame so I’ll add

00:01:35a half inch a per bit to my router and

00:01:37trim the outer edges

00:01:38I built this router right into my

00:01:40workbench so I have a lot of room for

00:01:41bigger projects look for how to build

00:01:44this router table in a different project

00:01:45these simple cuts are quickly giving the

00:01:48frame a more professional look okay

00:01:50those are done so now I can retract my

00:01:52router bit and lay these support blocks

00:01:54down the lens goes over top and these

00:01:56blocks are helping prevent the lens from

00:01:58warping when we’ve got one of the

00:02:00corners lined up we can drill a pilot

00:02:01hole and add a three-inch wood screw

00:02:03that’s holding well so let’s repeat that

00:02:05on the other three corners drilling

00:02:07these holes first helps prevent the wood

00:02:09from splitting when the screws go in the

00:02:11scorcher lens is framed and we can put

00:02:13that off to the side and get to work on

00:02:15making a collapsible a-frame this time

00:02:17we’ll need to cut to 5 foot lengths of

00:02:192×4 and rip them into two by twos the

00:02:21same as the others

00:02:22I want to make a hinged frame but before

00:02:24we do let’s router these edges as well

00:02:26and save some of the sawdust for a

00:02:28future charcoal making project all right

00:02:31my table is clean again and I’m going to

00:02:32try an idea for a modified hinge with

00:02:34these eye screws these screws were six

00:02:36for a buck and will only need four holes

00:02:39are drilled in the center of the

00:02:40chamfered edge and then these screws are

00:02:42tightened to where they line up nicely

00:02:43with each other they stay together

00:02:45closed and fully open so I’m hopeful

00:02:47this is going to work it’s time to join

00:02:50the a frame with the scorcher lens a

00:02:52washer and nut go on the bolt and now

00:02:54I’m cutting this barbed sprinkler line

00:02:56coupling to act as a spacer the barbed

00:02:58is on with a washer on either end and

00:03:00the eye screws are added next followed

00:03:02by a washer barbed washer and secure it

00:03:06in place with a wing nut everything is

00:03:08duplicated on the other side and these

00:03:10frame legs pivot just the way I was

00:03:11hoping next we’ll need to measure the

00:03:13distance between the legs and cut four

00:03:15more pieces of wood to act as support

00:03:17braces when those are roughed in place

00:03:19let’s measure about 10 inches from the

00:03:21scorcher frame and make some marks when

00:03:23we’ve drilled the holes and added the

00:03:25screws the frame is pretty much done the

00:03:27scorcher lens rotates a full 360 degrees

00:03:30and seems relatively sturdy one more

00:03:33thing I want to try is adding an

00:03:34adjustable tensioner so I’m cutting a

00:03:36scrap piece of 8-inch cardboard into a

00:03:38strip about two inches wide and 18

00:03:40inches long then I’ll adjust the saw to

00:03:42cut a groove in the center stopping

00:03:44about one and a half inches from the

00:03:45ends a hole is drilled in the frame ten

00:03:48inches from the top and the band is

00:03:49connected to the frame with a three inch

00:03:51bolt and some wide metal washers a wing

00:03:54nut will hold that together loosely then

00:03:55this other end of the strap connects to

00:03:57the side of the pivoting frame about

00:03:59five inches from the fulcrum loop steps

00:04:01a little too tight so I’ll back it off a

00:04:02touch and give it a test

00:04:04I can still rotate the lens nearly 360

00:04:07degrees but now I have the benefit of

00:04:08being able to position and

00:04:10securely at any angle I want the frame

00:04:13looks great and totally exceeds my

00:04:15expectations for functionality and

00:04:16practical use the best part is we made

00:04:19the whole thing custom for about eight

00:04:20dollars that’s it for now if you like

00:04:23this project perhaps you’ll like some of

00:04:24my others check them out at the king of

00:04:26random comm