/diy/ - Do It Yourself

>>819189
A few more pics of my main one. The smaller box, is just a bread riser box. Though the same thing can be done using the main solar box oven without its reflectors. One the bread has raised, just pop on the reflectors. I use hooks and bungees to hold the panels on.

It cooks anything you can cook in a conventional oven.

>>819120
>one-way mirrors

Joke aside, don't use these (I've seen people use them before!) They will shatter. You need to use tempered glass for the inner glazing and then you can use normal glass for the outer glazing. Don't use more than 2 panes of glass and don't use mirrors. The mirrors will actually reflect more light and not work very well. Just normal panes of glass reduces sunlight by as much as 10% per pane.

With these 4-panel solar ovens, you always need to use 2 glazings and the inner one must be tempered glass.

>>819118
Build a well-insulated box. Essentially a box inside a box with about 2 inches of insulation between them. The insulation can be layers of cardboard, crumpled newspaper, old cloth, or actual fiberglass insulation. Make a lid access into the box and an angle-adjustable floor inside the box. Don't use the glass as a lid.

Use 2 panes of glass over the top with about 1/8" air space between them. The inner glass must be tempered glass or it will break in the heat.

The reflective panels are best made as Trapezoids, not rectangles. Then you can put hinges on them. You'll be able to take them off and fold them up together for storage.

A good solar box oven with good insulation, double glazing, and large trapezoid reflectors can reach 450F in under 15 mins very easily. With food inside the temps will read far less until the food is finally being fully cooked. After that the temps rise sharply.

Don't try to cut your own tempered glass. Buy it pre-cut and design your box to fit.

Here's one mine. (old reposted pics)

>>616229
>>616252
>>616254

You eat it with a spoon out of the jar, not as a single muffin. You could use a wide mouth freezer jar. Those are sloped so you can get stuff out in one piece.

>>616007
Plans for making the funnel reflector panel. The jar in that image just has coat hanger wire for the bail and bag support. It has to have a plastic bag around it to help with wind and the bag can not touch the cooking vessel or it'll melt right away.

>>615816
There are also funnel cookers that do a pretty good job, but aren't as fast cooking a lot of the time. Depends on size really.

>>616004

>>616002

>>615816
Not too much to tell really. The box itself just needs to be insulated really well. You have to use 2 panes of glass with 1/8" - 1/4" air space between them and the inner glass must be thermally treated glass so buy it precut to the exact dimensions needed or size your box to match whatever you have on hand. The panels to reflect light need to be trapezoid shaped and you use 4 of them, one on each side of the box.

When empty, the temps should reach around 400F-450F, but when you put food in them all that heat gets absorbed by the food. So, the temps you get will to be much lower. Like 300F-350F. Which is good because you don't want it combusting into a ball of fire.

>old pics

>>615738
The worst of the solar cooker designs really. You can reach frying temps with a solar box oven with correct panel design and it is far better since you can cook family size meals in them in the same time as a conventional oven. You just have to design them correctly.

But, to do your project you can have it up and running in about 20 minutes of assembly if you have all the parts. It should take about 3-5 mins to fully cook a single hot dog on a stick.

All you need is cardboard, wood/elmer's glue, and aluminum foil. Something to hold the hotdog (coathanger wire) and something to keep the shape of the cardboard (string) is all you really need. Mix the glue half and half with water and brush it on the cardboard then lay on the aluminum foil, shiny side facing out, and let it cure.

All you need are two strips of cardboard about 1 foot wide by around 3-4 feet long. You can glue pieces of cardboard together by overlapping them and using the glue mixture then compressing them together with books. That's what I do to make larger panels of cardboard. Once the glue is dried, make a big plus sign out of the 2 cardboard strips and glue them together like that. Then apply the foil to them.

Punch one hole in each of the ends of all the plus sign ends. Run a string through the holes of two ends that are across from each other. Start tightening the string up to bring up the ends to make the parabola. Do this with both sides. You may need to bend the cardboard in many places to give it a segmented appearance so you can get the shape just right. You want the focal point to be well below the string since you don't want to burn the string. Do that by making the dip of the parabols deeper.

Then turn it towards the sun, prop it up correctly, and put a hotdog in the center of the focal point. If it does not cook the hotdog fast enough for you then you can add 2 more strips of foil-covered cardboard and make it into an 8-ended shape instead of a 4-ended plus sign shape.

>>452701
>Is that styrofoam under the mirror ? Wont that melt ?

No. There's no concentration of sunlight there. In fact the mirror is reflecting the sunlight away from it. I wouldn't use foam for that anyway. It isn't very durable for such outdoor uses as that.

>insulation

For a solar box oven, only use cardboard, not wood, unless you need a box frame. Bubble foil uses plastic, you can just use cardboard for insulation too. Cardboard will shrink after the first couple uses so expect to add a couple extra layers in after that. Fiberglass insulation will work well too.

>plexiglass

Use real glass. Two layers is best with 1/8" air gap between them. The inside glass needs to be tempered glass so it won't shatter. Plexiglass will melt as will foiled bubble wrap if they are in contact with the cooking heat.

>50 CM of mirror-space

Use foil glued to cardboard or mirrored metal, but not glass mirrors for solar box cookers. Use 4 reflector panels, 1 on each side of the box.

>cooking

Check these out,

http://solarcooking.wikia.com/wiki/Solar_Cookers_World_Network_%28Home%29

http://solarcooking.wikia.com/wiki/Category:Solar_cooker_plans

Here's an old pic of one of mine. A prototype camping solar box cooker. The towel is an additional the insulator. The main insulator was 1 inch of cardboard. It also used 2 pieces of normal plate glass (higher temp cookers need tempered glass on the inside). Cooking time at that low a temp (250F/121C max) was about 2.5 hours.

>>452456
Ambient temperatures don't play much role in solar cookers. You can cook even on slightly overcast days with a good solar box oven.

I've used mine in the dead of winter when temps are as low as -5F and still cooked food in about 45-60 minutes, depending on the thermal mass of the food I'm cooking.

>>451881
Parabola solar cookers need to be adjusted very often, like once every 15 minutes at most. With a well designed solar box oven you can only need to adjust it once every hour or so, but once every 30 minutes would be optimal of course. The trade off is that a parabola solar cooker can give you near instant frying temperatures if it is designed correctly.

>how I can allign all the mirrors.

Build it indoors. Let if face a single light in a dark room. Use that light to help align the mirrors by aiming the reflection to the pot holder area.

>detatchable and re-aimable ?
>way to rotate the whole contraption ?

Yes, but as >>452400 states, aiming them once then just moving the dish is a far better solution. You can add a heliostatic device to track the sun if you want. I can be a mechanical timer based (egg timer + lazy Susan) or electronic based that actively tracks it, but will need an electric source of some kind. You should at least have some way of easily adjusting it on 2 axis because the focal point of these things is very small and goes off quite quickly. For my box cookers, I just prop them up and/or rotate them as needed on wheels.

>should I use to raise the thing I want to heat up ?

The pot holder needs to be metal. You can use a welded wire grid so that more sunlight strikes the bottom of your pot/pan directly.

>better alternatives than tiles of mirrors?

That is the best you'll get for a parabola solar cooker.

>any idea's ?

As stated in >>451897 you can make a fast cooking solar box cooker. My best ones reach 450F in a few minutes, but are for baking, not frying, unless I want to fry at 450F or less. I use my Fresnel lens for frying.

>>441709
Yes.

It's easy too. If you live in an area where water won't freeze, in the winter, then make a solar batch water heater. If you live in an area where it will freeze then you'll need to insulate it well or use an antifreeze thermosiphon circuit like in this image.

http://www.builditsolar.com/Projects/WaterHeating/water_heating.htm

>>441669
>What's the thing on the lower right picture for?

The smaller box? It is a bread riser. I was using it while setting things up and taking pics. I don't need it when doing 1-2 loaves because I can use the main solar cooker to raise bread when its reflectors are not attached.

>What are the reflective surfaces made of?
>Would cardboard with aluminium foil on top suffice for such a device?

1/4" plywood (luan board) with aluminum foil (shiny side up). I used a mixture of half water and half wood glue to glue the foil to the board. You can also use cardboard. Most of my cookers used cardboard. You can patch pieces of cardboard together with the same glue to make larger panels.

>How much would the efficiency of the cooker suffer if you removed the glass?

It might reach 150F with the glass off. A single pane of glass is prone to wind. A double panes of glass is the best. Make sure to use tempered glass on the inside pane or it will shatter. Without the glass, it would be a simple panel cooker ( http://www.wikihow.com/Build-a-Solar-Panel-Cooker ).

>And can you estimate how much the size of the model in your picture could be reduced if the required peak temperature was only around 200F?

On a sunny day, just about anything that traps heat with even a single small reflector will get to 200F easily. The more reflector space you have the faster it will get there and the hotter it will be. The more insulation you use the better.

Solar cookers are super simple to make and use. The only slightly difficult part is getting high temps in a short amount of time. When in doubt, add more reflector space and more insulation.

>>441619
Solar box cooker the reflector the style of Heaven's Flame or the All Season Solar Cooker and very well insulated will be best for heat gathering and retention. One of my old cooker, pictured here, has double glass and high R-value insulation. At its peak it could reach 450F, with nothing inside in about 15 minutes.

http://solarcooking.wikia.com/wiki/Category:Solar_cooker_plans

http://solarcooking.wikia.com/wiki/Category:Solar_cooker_designs

>>435220
My apologies, my copy/paste function failed me,

>Lalvin's "Importance of rehydrating yeast"
http://www.lalvinyeast.com/importance_rehydration.asp

>>435220
>>435223
I highly suggest you read this very informative link,

>6.5 Preparing Yeast and Yeast Starters
http://www.howtobrew.com/section1/chapter6-5.html

>>435214
This is why it pains me to see so many plastic buckets for starter kits. Though some of my best and award winning brews were made in plastic containers, I've moved fully to glass and stainless steel now since consistency is needed for my brewery.

Alas, these things are fine for the small hobbyist.

>>435214
This is why it pains me to see so many plastic buckets for starter kits. Though some of my best and award winning brews were made in plastic containers, I've moved fully to glass and stainless steel now since consistency is needed for my brewery.

Alas, these thing as fine for the small hobbyist.

>>435208
>I thought we lived in America. you know, a first world country where our drinking water was sanitary?
>You can rinse with sanitized equipment with tap water and be perfectly fine.

Incorrect. Tap water is merely safe for human consumption. It does not carry a guarantee for not contaminating your brew.

>Wooden spoons don't need to be boiled

Wood is porous. Regardless of how many times or how long you use a no-rinse sanitizer, it can not fully get into the pores of the wood unless the wood has been heated and pressurized. During the course of your brewing there is ample time for deeply set bacteria and wild yeasts to come out of the wood and into your brew. Fully boiling the wood prevents this from happening.

>>435211
Some brands recommend directly on their label stating you should make a starter and pitch the yeast. Not everyone makes wine after all.

>>435171
>24-hour starter

These additional hours depends on the yeast strain and you learn as you go. Many of the lighter yeasts for white wines take ages to properly activate while more vigorous strains like EC-1118 are so vigorous you can sprinkle them right on top of the must and away they go.

>>435185
>correct, bread yeast is prison tier

Incorrect. Prison brewing is "pruno" and a completely different type of fermentation, usually employing, though inadvertently, bacteria.

>full of shit. dont listen to this guy about this one. they are perfectly fine.

They are not. Certain plastics degrade and release chemicals more readily in an acidic environment starting as 5.5pH. Other plastics like those used for Better Bottles are good for primary fermentation. I don't recommend doing secondary fermentation or aging in them. Age in your bottles at least, or in glass/stainless steel containers if you really need the consistency during aging.

>>435195
...continued

Don't rinse with water that has not been boiled. You are merely recontaminating your equipment. Always scrub your hands well prior to making your brews. Properly sanitization/sterilization is basically for consistency with your brewing, so that each identical batch you make will taste as close to each other as possible. Most contaminations are minor and are wiped out by the yeast's natural defenses during the initial fermentation. Racking and bottling is the most dangerous time for brew contamination. During these times the yeast is dead and/or dormant and can no longer defend against contaminations. Take extra care when you rack and bottle to prevent contamination.

>>435194
...continued

Wooden spoons, vinyl/plastic racking tubes, reusing fruit bags, and plastic buckets/carboys. These can inadvertently be sources of contamination if they are not properly sanitized. Wooden spoons would need to be boiled for 10 minutes between brews, if you use them, though I highly recommend just using stainless steel spoons. Fruit bags need to be wash normally then boiled for 5 minutes to sanitize them. You can use a no-rise sanitizer with these if you wish. They can be sterilized in an autoclave/pressure cooker if you wish. vinyl/plastic tubing is normally best sanitized in a pot of no-rinse sanitizer for an extended amount of time. Plastic buckets/carboys all should have extended times of sanitization. For all vinyl/plastic equipment use water that is very hot, but not close to boiling as your sanitization medium. This helps get into any surface scratches.

These items can be used and can be sanitized properly, however, most have alternatives that are better suited to be sanitized or even sterilized. Use stainless steel and glass when possible. You can bake glassware at 350F/176C for 2.5 to 3.5 hours to sterilize it (make sure the glassware has cooled before opening the oven or it may shatter due to thermal shock.) Bleach can be used to sanitized and sterilize. To sterilized you need to let the items stand in bleach for 20 minutes or more. Sanitization only needs a cursory 2 minute wash over. Rinse the bleach off using boiled and cooled water.

>>435171
>Using bread yeast: Don't ever do this. It has next to zero alcohol tolerance and the flavor will be a far cry from what it could be if you used a proper dry ale/wine/champagne yeast. It's called bread yeast for a reason.

Incorrect.

You can use Fleischmann's Active Dry bread yeast to replace Lalvin's EC-1118 champagne yeast. Any recipe tailored to EC-1118 can use it. Any recipe tailored specifically to Fleischmann's of course can use it too. It is unlike other bread yeasts, fyi. I've been able to attain 19%ABV on a number of occasions using Fleischmann's. Like all yeast variants, you really need to know your stuff if you want to have your brew excel. You can't simply make anything with Fleischmann's and start drinking it a week later. Like most brews, you need to age it for at least 1 year for a white, 2 years for a dark, and up to 10-20 years for pure black elderberry.

If you don't know how to use Fleischmann's properly or you swap it into a recipe not designed for EC-1118 then you will be altering the recipe and won't get the exact results you'd hoped for. Other bread yeasts, I cannot vouch for in the slightest and some can make horrific brews; from which most of the anti-bread yeast sentiment comes from.

>You know those blue plastic carboys you see used for water? Don't ever use those are homebrewing.

Agreed. However, only for the BPA, not specifically the oxygen. That is of little concern prior to aging. If you are trying to age your brew in plastic then you may have oxygen problems. During the primary fermentation stage oxygen infusion from migration through plastic won't matter. You will get far more oxygen into your brew when you rack it even when using CO2 or argon to help prevent it than will ever migrate through the plastic during primary fermentation.

>Anything else I can try to cover?

How about proper sanitation/sterilization methods and tools you should/shouldn't use if you can help it?