White Belt's Military Journey to FI

Where are you and where are you going?
Hristo Botev
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Re: White Belt's Military Journey to FI

Post by Hristo Botev »

I wouldn’t overthink the safety razor thing; there’s nothing to learn. It’s really no different than shaving with a cartridge type razor.

macg
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Re: White Belt's Military Journey to FI

Post by macg »

white belt wrote:
Sat Jan 01, 2022 10:03 pm
Sure, not every area has rent increases that keep pace with inflation (many HCOL areas outpace inflation). The Fed still buying mortgage-backed securities and ZIRP means property values have increased faster than inflation. If you want to allocate more money to housing you can, but I'm just saying that there are very few people that can make 1x JAFI work with housing costs greater than $400 a month. If you live in an area that doesn't require car ownership or regular use of public transportation then you might be able to make it work with higher housing costs (e.g. transportation costs are ~$0).
Yeah, agreed. Personally, I kind of ignore the housing piece of a JAFI, because I want to live by myself, in hot weather, near to the ocean, and (for now but maybe not much longer) in the US. And yes, I know these are "wants", not needs. So factoring in these wants, I could never get to 1x JAFI. That being said, if you take housing out, I am below 1x JAFI. I'd have to do the math for this past year a little more, but I think I can even say without housing I am well under 1x JAFI. So there's that lol

white belt
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Re: White Belt's Military Journey to FI

Post by white belt »

macg wrote:
Thu Jan 06, 2022 10:35 am
Yeah, agreed. Personally, I kind of ignore the housing piece of a JAFI, because I want to live by myself, in hot weather, near to the ocean, and (for now but maybe not much longer) in the US. And yes, I know these are "wants", not needs.
There are ways to do that without spending a ton of money on housing, although perhaps you could argue that some kind of work exchange for discounted rent should just be treated as a part time job for accounting purposes. @Ego is an example of someone who lives in a HCOL coastal area on the cheap. I would think that there would be opportunities for house care-taking or similar gigs in a warm coastal area that probably has a lot of vacation homes. Then there are the various alternative housing solutions like RV/van living, boat living, etc which I'm sure you've probably already explored.

white belt
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Re: White Belt's Military Journey to FI

Post by white belt »

I suppose this is the obligatory year in review. I don’t have good spending data for the first half of the year, so I probably won’t deep dive the financial aspects too much. My net worth went up a lot due to savings and high market returns. That seems to be the case for just about every other journal on here as well.

I’ve read through most of my journal entries and man does it feel like I’ve grown a lot this year. I developed some skills in investing, cooking, and dating that have helped me to ratchet down my expenses.

Food
I’ve added a lot of new recipes to my repertoire. As a result, I no longer eat out as a form of entertainment and now can make many of my favorite gourmet dishes at home. My food spending has dropped off significantly.

I still would like to improve personal resilience by limiting the frequency of my grocery visits. The foods that require frequent re-stocking are fresh fruits and veggies. I think I can replace the sauerkraut mix I enjoy with microgreens if I stay on top of things. I’d like to substitute with more garden veggies and fruits, but that’s not possible during the winter. I like bananas a lot so they will be hard to give up.

Another level of resilience would be to use a cooler as an icebox instead of a refrigerator. I’ve written about it before and I think using ice blocks from the freezer that I replace once weekly would do a lot increase my resilience against short term power outages.

Dating
My dating life took some unexpected turns this year. I started the year in an open relationship with DGF, then we dated exclusively for a few months, then we broke up and I was single for a few months at my new location, then we decided to get back together and I have been monogamously dating DGF for the past 3 months. Overall it has gone very well and we were able to spend a lot of time together despite the long distance over the past few months. These next few months will be a test because she will be much more stressed with school and we might only be able to see each other in person 1-2 times a month (we got in the habit of seeing each other every week or 2 over the past month).

After some retrospection, I’ve realized that I was really using my dating life as a source of excitement and novelty at times when I felt bored or uncertain about what to do next. There is still some novelty and excitement in a monogamous relationship, but of course it is different than when I was going on multiple dates with new girls in a week. However, my single life dating really took up a lot of time and attention; not just with going on dates but all of the energy and effort associated with online dating. I think in some sense it gave me a sense of purpose. I’ll have to think about how to make sure I am getting excitement and purpose in my day to day life while I’m in a monogamous relationship (not just sexual/romantic excitement, but I think also stuff that challenges my brain).

Investing
Over the past year (well mostly the past few months), I’ve read a number of investing books that are widely recommended on these forums. Everything from textbooks to popular nonfiction tomes like Antifragile and What I Learned Losing a Million Dollars.

I am still a beginner investor. I’ve settled in to a dragon portfolio-ish allocation for most of my portfolio. I also now have a small allocation that I put towards more short-term asymmetric trading opportunities. Still not really sure if I know what I’m doing, but at least have a better idea of what a lot of the words mean now. I have a rudimentary understanding of options and have begun to dabble in them for trades in which I'm looking for a specific payoff profile.

Current Situation
I suppose I should take some more time to reflect on my current situation. I think I have a tendency to be so future focused that I neglect the present. I’m grateful for my relationship with DGF, my current location close to friends and family, and for my financial success. I have time to pursue my own interests at work, even if the rotating shifts and lack of fulfillment are a challenge.

It’s clear I need another hobby, but I’m unsure of how to approach it. The times I can recall being most fulfilled in my life were when I was immersed in learning a new skill (guitar, Mandarin, infantry maneuver, tech skills, weightlifting). At the end of the day, feeling a sense of structure and progress helps me to relax and better enjoy the rest of my life. I tend to get hyper-focused and obsessed with such things, so I’m not exactly sure if that’s a positive thing or a sign that I’m using it as a distraction from something else. I’m open to input from others on this topic.

I was reminded of how much I enjoy taxing my analytical brain with dynamic problems after playing Catan for a couple of nights with friends. I was fully engaged in a flow state and reminisced about all the time I spent playing WH40k and MtG in my childhood. I’m not sure if I want to add boardgames or similar games to my list of activities because I question the larger utility within my web of goals. Playing boardgames isn’t really a skill that will help me to become more resilient or antifragile. Maybe that shouldn’t be the benchmark I use for choosing activities.

white belt
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Re: White Belt's Military Journey to FI

Post by white belt »

Hristo Botev wrote:
Mon Jan 03, 2022 4:14 am
I wouldn’t overthink the safety razor thing; there’s nothing to learn. It’s really no different than shaving with a cartridge type razor.
After a few days, I pretty much have it down. The only parts that are still a little slower are shaving the curved surfaces around my jawline and chin. I'm not sure if the cost savings are that great because I think I'll still have to swap blades once a week, but at least I know I'm not putting as much plastic in a landfill as when I used the name brand disposable cartridges.

I shaved with a straight razor for a few years but found it to be too much of a hassle to keep the blade sharp on a daily basis. There was definitely a learning curve with that one though because if the angle was slightly off, you were going to probably cut yourself.

Hristo Botev
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Re: White Belt's Military Journey to FI

Post by Hristo Botev »

white belt wrote:
Mon Jan 17, 2022 11:57 pm
I'm not sure if the cost savings are that great because I think I'll still have to swap blades once a week,
Reposting this here b/c Classical_Liberal saved me a TON vs what I'd been spending for razors at the CVS I walk by on my walk home. Basically, for 10 razors for the price of $10 at CVS it's 100 through this link. I can vouch that there are what they claim to be, as these are the razors I use. Swapping out once a week (I can generally go once every 2 weeks, but I have a goatee of sorts, though I also shave my head), this is roughly 2 years of razors for less than $10.
classical_Liberal wrote:
Thu Sep 17, 2020 8:07 pm
Not sure if you're anti Ebay? I dislike Amazon as well, for some of the same, and some different reasons as you. The only thing it really has over Ebay is Prime shipping anyway. But I'm never in a hurry to get my stuff, so it's meaningless to me. Here's 100 on Ebay for a couple bucks more than you're paying at CVS for 10. Ebay is my "go-to" for this type of stuff(if not at Costco), also it's a gold mine for random parts to fix random stuff.

white belt
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Re: White Belt's Military Journey to FI

Post by white belt »

Trading is interesting. I keep making profitable trades but I still can't ascertain if it's just luck. I grok process orientation for trading, but I also grok that making money is what matters. It's not about trades being right or wrong, it's about trades being profitable or unprofitable (at least that's how Jim Paul recommends thinking about it in order to mitigate ego involvement).

I made over a month's worth of expenses (~4.5 bagger) by risking $500 for 3 weeks*. I'm hesitant to consider this income because I don't know if it is replicable, but it does make me think about cashflow differently. I think it qualifies as an asymmetric bet in the Taleb framework, but maybe I'm just deluding myself because I haven't lost a lot of money yet.

* = I don't monitor my larger investing portfolio more than once a month, but I'm sure my net worth decreased by far more than a month's worth of expenses in the SP500 correction over the past week. However, there is a difference between paper gains/losses and real gains/losses, so I'm trying to keep things distinct in my mind. I think of my trading portfolio as completely separate from the rest of my investing portfolio. Maybe that distinction is trivial, but it helps to keep me honest about what frameworks are appropriate for trading vs investing.

white belt
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Re: White Belt's Military Journey to FI

Post by white belt »

December Report
Expense Total: 2200

I won't go into categories, but the increase in expenses was due to gifts and additional traveling over the holidays.


January Report

Expense Total: 1762
Housing - 800
Food/Restaurant - 400
Dating/Social/Entertainment/Alcohol/Bars – 150
Car/Transportation/Insurance/Travel – 102
Health/Fitness – 71
Other - 200
Cell Phone/Music - 39

Light on the travel spending this month, which explains the reduced expenses. For accounting purposes, I track travel expenses for the month that the travel occurs, not the month I book tickets. I spent a bit more on restaurants and entertainment due to the holidays.


Financial Snapshot
Rolling 3 month expense average: $1840
Net Worth: $423k

Net worth predictably declined slightly due to recent stock market correction. Current allocation is still around 38% equities which will gradually decrease as I increase portfolio holdings for other categories. I don't want to sell any equities because that would trigger a taxable event, but eventually I'd like to get down to ~25% equities. Short term trades are ongoing so TBD if those will be profitable.

mathiverse
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Re: White Belt's Military Journey to FI

Post by mathiverse »

Hey white belt,

Do you have any podcast recommendations for learning about investing? If I recall correctly, you recommended macrovoices at one point. Any others?

white belt
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Re: White Belt's Military Journey to FI

Post by white belt »

mathiverse wrote:
Tue Feb 01, 2022 8:58 pm
Hey white belt,

Do you have any podcast recommendations for learning about investing? If I recall correctly, you recommended macrovoices at one point. Any others?
Most economics/finance podcasts are pretty advanced because they are targeted to a professional audience. I’m talking about experienced traders and fund managers for whom a CFA is the baseline just to get an entry level job. So I’d encourage you to work through the investing/finance curriculum of textbooks that Jacob recommends alongside listening to podcasts if you aren’t already a sophisticated investor. In my opinion, the podcasts can help to solidify textbook concepts by providing real world examples. The podcasts will also expose you to a wide range of ideas and thinkers, just don’t expect to learn investing 101 from the podcasts I recommend.

My favorites are Macrovoices and the Market Huddle (both are weekly podcasts that summarize recent markets and have long form interviews). If you want to follow daily markets, the Real Vision Daily Briefing is pretty good and tends to simplify things for a broader audience. Superinvestors with Jesse Felder is also good for long form interviews but is updated less frequently. Smarter Markets is interesting if you want to learn more about the intersection of economics, technology, energy, and climate change (just expect a large dose of techno-optimism). I listen to everything at 2x speed.

mathiverse
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Re: White Belt's Military Journey to FI

Post by mathiverse »

Awesome, thanks!

white belt
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Re: White Belt's Military Journey to FI

Post by white belt »

I drove down to visit DGF for ~5 days instead of flying because a flight got cancelled. The ~500 mile drive wasn't terrible since it's almost entirely easy interstate miles. I listened to music and podcasts which was fine, but I did get a bit stir crazy towards the last 2 hours of driving. It was nice having my car with me during the visit to do activities during the day since she lives in a car-centric area. I may drive again if I can figure out how to stay for 5 or more days again, otherwise it's just too much driving for such a short trip.

In a way, I got a taste for what retired domestic life would be like with DGF. She was busy working 10 hour days and studying a few hours in the evening, so I had a lot of time on my hands. I actually should have brought more stuff and lined up more projects in hindsight. I was originally going to do my taxes but realized I didn't have all the forms I need yet. I found puttering around on DIY home improvement projects for her house surprisingly fulfilling. In fact, this confirms that I think I would quite like to do more of that in the future. Since I'm renting, there aren't a ton of opportunities or motivation to work on projects in my own house (although I have offered to help the landlord with landscaping in other projects before). However, I do have a list of projects to work on with DGF like building a work bench in her garage, building wood pallet planter fence for the backyard, helping her to widen a doorframe by a quarter inch to fit a new door, and other things. Nothing crazy, but I think they are easy things that would teach me some useful real world skills and also improve the DGF's enjoyment of her space. Maybe I should just be a house husband.

I'm still wrestling with what exactly gives me fulfillment when I'm not working a job. I've come up with the following things to include each day:

-exercise (usually lifting weights, sometimes cardio or sports activity outside)
-projects (DIY, tinkering, random climate change related projects, whatever tickles my fancy to learn about)
-socialization

I think that's really it. The exercise and projects help give me a sense of satisfaction and progress, while the socialization forces me to interact with others and get out of my own head for a bit. If I'm traveling then I tend to not be able to work on projects as easily, which I've come to realize leads to a sense of boredom and even frustration after more than a couple days. I very much get satisfaction from feeling like I'm doing something useful, even if it is as simple as installing a mirror or a shelf. I seem to really enjoying improving the functionality of spaces, perhaps because there is a lot of optimizer in me.

Speaking of projects, let's take a look at the list I've come up with:

Transportation
-fix broken spoke on bicycle (complete - had to pay to get fixed)
-fix weather stripping on car (preliminary research looks more difficult than expected, will research further)
-change oil
-fix passenger window switch
-disable always-on daytime running lights
-clean battery

My drive down seemed to rekindle some connection with my car; it's really a great vehicle and keeps on chugging along at ~177k miles (Toyota mechanicals so 250k-300k miles is quite common). DGF and I had some conversations about moving in together once my Army commitment is complete and she agreed that my car would the much more practical car for us to share compared to her pickup truck. At first I was planning on selling it as soon as possible once my job allows it, but now I've shifted to keeping it running as long as possible. DGF is also eager to learn to drive stick, so that will be a thing that happens at some point. Even though the plan is for us to live in an urban environment with good public transportation, I still think it will make sense for us to share a vehicle between us. My car is fuel efficient, has a ton of cargo capacity, and even has the capability to tow or haul things on a roof rack. I've learned that it's a popular camper vehicle and got some good ideas for modifications from youtube videos. My bike is again my primary commuter for work and errands now that it's fixed. However, I still use my car for >2 hour road trips once or twice a month and other niche purposes where a bike won't cut it.


Food
-start growing microgreens again (complete - very easy to grow with no issues, need to start new batch)
-tempeh (probably on hold for winter months, may try again if I get seed starter mat)

Microgreens were an nice win to get me back on track after the recent tempeh failures. I didn't start a follow on batch because of the traveling, but I plan on starting a new tray soon. For now I'm just using new soil each time, but soon I'll incorporate my worms to try to re-use soil, assuming they've survived through the winter.


Resilience
-install low flow toilet conversion kit
-capture warm up water from navy showers for drinking
-start cutting my hair again (in progress - mounted additional mirror in bathroom)
-learn to shave with safety razor (in progress - need to try razors @Hristo recommended)
-learn to darn socks

I've gotten the itch to optimize my water consumption again. My solution space is what can be retrofitted without requiring significant behavior modification because I don't plan on ever living alone again. I currently have my own bathroom, so I can make some modifications to reduce water flow in there. I plan on installing a dual flush low flow converter kit for my toilet, which I can easily swap back for the original toilet pump when I move out. I also installed my 1.5GPM showerhead and have gone back to navy showers. I also have a .5 gallon aerator on my bathroom sink. I'm trying to get comfortable living a good life while minimizing my water consumption, with the goal to prepare myself for my own rainwater harvesting system and maybe even living off grid in the future. I'm really saving my landlord money on his water bill, so perhaps I should show him some of my upgrades and see if he thinks they are worthwhile to implement for the downstairs bathroom and kitchen.

white belt
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Re: White Belt's Military Journey to FI

Post by white belt »

I scored a used 4L Thermos Shuttlechef Thermal Cooker on eBay for $80. This is a real deal vacuum-insulated thermal cooker, so I plan to see if I can use it as an instapot replacement to make rice, soybeans, yogurt, stews, etc. This provides me some flexibility and efficiency because I only need to bring the contents to a boil initially, which is possible on just about any heat source. The idea is to down the line incorporate a parabolic solar cooker, small rocket stove, and/or propane camp stove to do the boiling (right now my only option is an electric coil stove top). That would allow me to take the entire cooking process off-grid at least for those types of foods. This idea is not original and was inspired by this article: https://www.lowtechmagazine.com/2014/07 ... oking.html

I've been researching solar cookers a lot over the past few days. I'm not so much interested in the slow cooking oven types, since I feel like those are already quite easy to replicate in something like a thermal cooker. I might feel differently if I was doing a lot of baking. Nevertheless there are countless DIY options that seem relatively effective to mimic the performance of a conventional oven.

I'm more interested in solar cookers that can boil water fast and fry foods in a pan. That leaves parabolic solar cookers in their various forms (fresnel lens, dish type, mirror type). Solar vacuum tubes can heat water quickly, however they can't be paired with conventional cookware for frying so I'm disregarding them for now. Fresnel lens are large and tricky because the heat is cooking the top of the food instead of the bottom. Dish types are too big and bulky for my purposes. I'm considering experimenting with something simple like this 17 inch parabolic mirror: https://greenpowerscience.com/PARABOLIC ... CSALE.html

I could put the parabolic mirror on a simple easel for adjustments and then rig up some kind of cook surface. Boiling water in a pot seems relatively straightforward because the water will naturally disperse the heat from the 1-3 inch beam size. However, for frying I might try to incorporate a high thermal mass tile/stone that acts as an intermediary to disperse heat evenly across a pan. The trick is to do this all without starting a fire in my yard or blinding myself, so I plan on dedicating all my attention to tasks like boiling and frying that are generally complete in 5-10 min (just like I would have to continuously feed a small rocket with twigs to accomplish the same thing).

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Slevin
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Re: White Belt's Military Journey to FI

Post by Slevin »

white belt wrote:
Thu Feb 17, 2022 2:20 pm
I scored a used 4L Thermos Shuttlechef Thermal Cooker on eBay for $80. This is a real deal vacuum-insulated thermal cooker, so I plan to see if I can use it as an instapot replacement to make rice, soybeans, yogurt, stews, etc. This provides me some flexibility and efficiency because I only need to bring the contents to a boil initially, which is possible on just about any heat source. The idea is to down the line incorporate a parabolic solar cooker, small rocket stove, and/or propane camp stove to do the boiling (right now my only option is an electric coil stove top). That would allow me to take the entire cooking process off-grid at least for those types of foods. This idea is not original and was inspired by this article: https://www.lowtechmagazine.com/2014/07 ... oking.html

I've been researching solar cookers a lot over the past few days. I'm not so much interested in the slow cooking oven types, since I feel like those are already quite easy to replicate in something like a thermal cooker. I might feel differently if I was doing a lot of baking. Nevertheless there are countless DIY options that seem relatively effective to mimic the performance of a conventional oven.
I'm super interested in using thermal cookers / haybox cookers as well (alongside a small rocket stove for cooking in the summertime, same inspiration as you); Super interested to see how that goes. The solar cooking seems really great in the right conditions as well (i.e. it is sunny out and you have a good line to the sun), I'm interested to see if you find it to be dependable enough to be a first (passive) source of heat, which is then backed up by a stove, etc. Out here I'm also generally entertaining 2-5 squirrels and dozens of birds in my backyard when I'm not deterring them, are you worried about running into little scavengers at all wherever you are cooking?

white belt
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Re: White Belt's Military Journey to FI

Post by white belt »

Slevin wrote:
Thu Feb 17, 2022 2:47 pm
The solar cooking seems really great in the right conditions as well (i.e. it is sunny out and you have a good line to the sun), I'm interested to see if you find it to be dependable enough to be a first (passive) source of heat, which is then backed up by a stove, etc. Out here I'm also generally entertaining 2-5 squirrels and dozens of birds in my backyard when I'm not deterring them, are you worried about running into little scavengers at all wherever you are cooking?
My region gets a fair amount of sunlight so I think it will be usable. I believe parabolic solar cookers are so strong that some can be used even on cloudy days, however I'm operating under the assumption that I will only be able to use it in direct sun. If it's cloudy then I can just use another heat source. I'm living in a house with a standard front yard and back yard, so I think I shouldn't have issues finding a spot if the sun is shining.

Parabolic cookers offer a few advantages over the traditional solar cookers. The biggest advantage is how fast they heat things. This means that I might only need 15-20 minutes of direct sun to complete a task, which greatly expands the practicality if I am somewhat flexible with my cooking times. This also means that I can attend to the cooker the entire time, so I'm not really too worried about critters interfering or associated safety issues with unattended cookers (I wouldn't leave a parabolic cooker unattended just like I wouldn't leave an open fire unattended). Once complete, the mirror will return to it's case and go back inside so there is no fire risk.

My plan right now is to start with using the parabolic mirror for boiling thermal cooker batch meals. I might make a week's worth of a dish at once which gives me some flexibility to plan around when the sun is shining. My understanding of virtually every thermal cooker recipe I've seen is that you bring the inner pot with contents to a boil for ~5 minutes to heat both the water and solids completely. Then I just place the inner pot into the thermal cooker and the rest takes care of itself. So all of the energy required for thermal cooking is really just used to bring something to a boil, which is why a parabolic cooker and small rocket stove (both burn super hot and fast) are great compliments to thermal cookers.

I think it will be trickier to use it for something basic like frying eggs for breakfast because that is a daily activity and more time-restricted. Baby steps for now and I'll build to that maybe.

white belt
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Re: White Belt's Military Journey to FI

Post by white belt »

Here's what I've come up with for a design to start:

17" parabolic mirror (~$70): https://greenpowerscience.com/PARABOLIC ... CSALE.html
Grill Tripod Cooker Stand: https://www.amazon.com/Stansport-Grill- ... ref=sr_1_4
5 gallon bucket
20 inch cymbal case (to store mirror when not in use)
Fire brick/stone/tile (needed to disperse heat for frying?)

I'm basically following this simple setup for now: https://www.youtube.com/watch?v=fgXzOvuLd_A

The specs on the mirror claims it can boil 12 ounces of water in just under 4 minutes, which I think is just about the same amount of time as most other forms of heating. If I can get that setup to work then I'll look into making a fancier tilt stand for the mirror.

Thoughts?

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mountainFrugal
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Re: White Belt's Military Journey to FI

Post by mountainFrugal »

Looks like a really fun project. For your fire bricks... are you thinking that you would heat them up first in the sun then heat up a skillet on top?

take2
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Re: White Belt's Military Journey to FI

Post by take2 »

I’ve never heard of this before but this is incredible. Cooking with the sun and a mirror! Amazing.

I will try and attempt a similar setup this summer

white belt
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Re: White Belt's Military Journey to FI

Post by white belt »

mountainFrugal wrote:
Thu Feb 17, 2022 5:36 pm
Looks like a really fun project. For your fire bricks... are you thinking that you would heat them up first in the sun then heat up a skillet on top?
One of the downsides of using something like the parabolic mirror is that it generates a small but extremely hot spot beam. The specs for the mirror I'm looking at say that with a focal point at 18" from center base, I can expect a 1" max power beam with an additional 3" scatter that provides some background heat. That max power beam can heat in excess of 1000F. I have two concerns with that:

1. It will warp metal cookware
2. It will be difficult to cook things evenly

Most people that use parabolic cookers seem to pair them with cast iron pans, yet they still often complain that it is difficult to cook things evenly due to how hot the spot is. With my thermal cooker, I'd like to just be able to boil ingredients directly in the inner pot for convenience. However, I worry that I might end up with some burned rice while I'm waiting for things to come to a boil (just as an example). This may be me overthinking the issue because I know water is a good thermal insulator and there will always be plenty of water in the things I'm boiling (obviously). Maybe the easier fix is just constant stirring but that doesn't address the warping risk.

Therefore, one thing I'm looking at is to use something like a garden paver to act as an intermediary between my pot and the beam. If you watch the video I linked, you'll see that the beam actually shines on the bottom of the cookware. So the idea is to place a brick/stone paver on the suspended cooking grate, then place my pot on top of the brick. Originally I thought a firebrick would be ideal, but after more reading it seems normal bricks should be able to withstand 1000F temperatures and will transfer heat better than firebricks. I don't know if this will end up being impractical because I have no idea how much extra time will be required to get the brick up to temperature and how much heat loss there will be between a conventional pot and brick. However, since the solar energy is free and unlimited, I'm not as concerned about thermal efficiency other than I don't want it to take forever to boil something.

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Re: White Belt's Military Journey to FI

Post by jacob »

white belt wrote:
Thu Feb 17, 2022 6:10 pm
One of the downsides of using something like the parabolic mirror is that it generates a small but extremely hot spot beam. The specs for the mirror I'm looking at say that with a focal point at 18" from center base, I can expect a 1" max power beam with an additional 3" scatter that provides some background heat. That max power beam can heat in excess of 1000F. I have two concerns with that:
Because you're building half of a telescope. Possible solution: Put the put somewhat outside the focal point ("out of focus") to spread out the beam (intensity is power per area). This might be 19" or 21" away from the center. The bigger problem is that anything but the smallest pot will block the incoming (parallel) beams from the sun. The system will only be (R/18)^2 percent effective, where R is the radius of the pot.

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