It makes sense for cosmetic companies to sell directly ready-made ingredients for personal care products. Green products sell for $10 to $20 a bottle vs $3 in Walmart for the tough-skinned. They have more vertical sales and we save a lot of money. Imagine saving moving the water around in those bottles! Making your own body wash isn't crafty and time-consuming anymore.
SLSA recipe
Water 200g (~ one cup)
SLSA 10 g (5% weight)
Glycerin 20 g (10% weight)
Essential oil 1 drop
Procedure: Dissolve SLSA in warm water. Stir and sit until you have a clear liquid. Add glycerin and essential oil. Bottle it. The clear liquid will turn into a white cream/paste after a few hours. I may be wrong but I think the glycerin "thickens" the solution.
I got a cheap electronic scale with 0.1 g resolution. But for these Chinese products, the accuracy may be +- 1g. So I might have brought one with 0.01 g resolution. The are about the same price. A higher resolution one has less range - can not take a heavy load.
You can find a 1 lb bag of SLSA everywhere, making hundreds of bottles of body wash with it. A bottle of vegetable glycerin is another $10; also it can make hundreds of bottles.
Depending on the hardness of your water, I would use 3% to 5% for body wash. And 5% to 10% for shampoo. The same for hand washing dishes; the glycerin is optional.
But is it any good? It's not as good as Castile Soap plus a lot of glycerin. But I don't feel dry after a shower. The shampoo cleans well for our hard water and oily hair.
SLSA is still an irritant in the same class of SLS and soap. If it takes off the oil of your skin, it can hurt the skin and eyes in high concentrations. Maybe SLSA is more gentle than SLS.
SLSA is an acetate, not sulfate, so hopefully, it cannot be manufactured in the same process as SLS, resulting in toxic contaminations.
The LSA ion is an organic compound with carbon chains; it had to come from living or dead living things. Derived from vegetable oil doesn't tell the whole story. As an organic compound, it is biodegradable in theory. To be eco-friendly, it has to be readily biodegradable. But I have seen no claims that it is degrading fast, which is important because, like most washing chemicals, they are toxic to aquatic lives.
The next project will be ready made chemicals that will be safe for humans and the environment. My requirement is "just add water".
Sunday, June 18, 2017
The quest for a safe and effective hair conditioner
Hair conditioner and other personal daily hygiene stuff rarely have a score of one on EWG. The low scorers are very expensive or simply not available. I have been making compromises between low score and reasonable price.
I have been using Bronner's Castile soap at 50 cents an oz. Increasingly I feel that's too expensive because the kids use it like water. It could be used diluted but that's not practical for kids. Nobody should have to suffer in preparing or using it.
I ran into my wife's SLSA. The time when I tried to homemade things these things aren't that available. After reading the good claims, I got myself a good body wash gel in no time by accidentally. It dawned on me that it only take a few grams for a cup, making it hugely economic even if you use the best ingredients.
I also worried about the preservatives that I need if I DIY. But then many ingredients are self-preserving like salt water, glycerin. I can always add sugar or salt, which are both good for skin if the Internet is to be believed.
At first, I believe in myself and how difficult can it be finding something that is slippery? I have guar gum that feels very slippery. I can turn it into gel using calcium in some pills. I can thicken it by cooking it, resulting in a stable and consistent paste as thick as I like it to be. Yes, it applies well and can emulsify oils you put in. But it did nothing to my daughter's very tangled hair.
I've tried egg, which works a bit but smells. I have tried protein powder to emulate the egg white, which didn't work. I came across blogs claiming that flax seed works the same as off-the-shelf conditioners. It felt much better than egg white but it also did nothing after rinsing off.
In between those natural things, I thought of using what the off-the-shelf conditioners use. I was scared off by the full name of BTMS, which sounded so chemical. Then I settled on the next thing down the list, emulsifying wax NF. It wasn't that good on EWG because the ingredients aren't disclosed (but supposed to be a national standard?). But the other emulsifiers have bad scores. And I'm sure wax alone doesn't do anything on tangled hair.
After reading so many good praises on various suppliers, I ordered BTMS and tried it. I just add 5% melted solid to glycerin and then to filtered water and it works perfectly. And it's so much cheaper than our safer conditioner. That would be the end of story until I read some negative things about BTMS. Worse, there are contradictions that don't inspire confidence in the industry.
BTMS (Behentrimonium Methosulfate) is unacceptable on the Whole Food list of premium products. But it scores 1 on EWG. OK, maybe Whole Food have some reasons that are not on the sources of the EWG database. Then I found out that people are confused because BTC (Behentrimonium Chloride) is on the Whole Food list but has an EWG score of 3, worse than BTMS.
OK, elementary chemistry tells me that when dissolved in water, the Behentrimonium ion does what the Behentrimonium ion does, whether the other ion is Methosulfate or Chloride. And that Chloride ion did nothing much as in common salt. I can understand EWG. If nobody research directly on BTMS, they consider it as limited data or no data. They don't review similar compounds as in CIR, the cosmetics review body. And the data on BTC isn't that good.
And I agree that WF is bullshitting. There is no scientist in charge of the list. If they want to sell a premium product on their shelf, they will make sure that all the ingredients are on the list.
I have been using Bronner's Castile soap at 50 cents an oz. Increasingly I feel that's too expensive because the kids use it like water. It could be used diluted but that's not practical for kids. Nobody should have to suffer in preparing or using it.
I ran into my wife's SLSA. The time when I tried to homemade things these things aren't that available. After reading the good claims, I got myself a good body wash gel in no time by accidentally. It dawned on me that it only take a few grams for a cup, making it hugely economic even if you use the best ingredients.
I also worried about the preservatives that I need if I DIY. But then many ingredients are self-preserving like salt water, glycerin. I can always add sugar or salt, which are both good for skin if the Internet is to be believed.
At first, I believe in myself and how difficult can it be finding something that is slippery? I have guar gum that feels very slippery. I can turn it into gel using calcium in some pills. I can thicken it by cooking it, resulting in a stable and consistent paste as thick as I like it to be. Yes, it applies well and can emulsify oils you put in. But it did nothing to my daughter's very tangled hair.
I've tried egg, which works a bit but smells. I have tried protein powder to emulate the egg white, which didn't work. I came across blogs claiming that flax seed works the same as off-the-shelf conditioners. It felt much better than egg white but it also did nothing after rinsing off.
In between those natural things, I thought of using what the off-the-shelf conditioners use. I was scared off by the full name of BTMS, which sounded so chemical. Then I settled on the next thing down the list, emulsifying wax NF. It wasn't that good on EWG because the ingredients aren't disclosed (but supposed to be a national standard?). But the other emulsifiers have bad scores. And I'm sure wax alone doesn't do anything on tangled hair.
After reading so many good praises on various suppliers, I ordered BTMS and tried it. I just add 5% melted solid to glycerin and then to filtered water and it works perfectly. And it's so much cheaper than our safer conditioner. That would be the end of story until I read some negative things about BTMS. Worse, there are contradictions that don't inspire confidence in the industry.
BTMS (Behentrimonium Methosulfate) is unacceptable on the Whole Food list of premium products. But it scores 1 on EWG. OK, maybe Whole Food have some reasons that are not on the sources of the EWG database. Then I found out that people are confused because BTC (Behentrimonium Chloride) is on the Whole Food list but has an EWG score of 3, worse than BTMS.
OK, elementary chemistry tells me that when dissolved in water, the Behentrimonium ion does what the Behentrimonium ion does, whether the other ion is Methosulfate or Chloride. And that Chloride ion did nothing much as in common salt. I can understand EWG. If nobody research directly on BTMS, they consider it as limited data or no data. They don't review similar compounds as in CIR, the cosmetics review body. And the data on BTC isn't that good.
And I agree that WF is bullshitting. There is no scientist in charge of the list. If they want to sell a premium product on their shelf, they will make sure that all the ingredients are on the list.
So I took the matter into my own hands and try to dig up the scientific data. The most useful one is National Center for Biotechnology Information that contains a lot of databases.
Before that, I got the CIR review of quats in general. Yes, they are not that good in general but there are so many things that can attach to the quats. So I found a reviewed compound with exactly the same structure but the carbon chain is significantly shorter. It's not that good but the bigger molecular weight makes a lot of different; larger molecules are more difficult to penetrate into the skin layer.
I did find two papers in one of the databases, PubMed, that settled the confusion. Bear in mind that the public database is often used by companies to attack and defense opponents. The papers are scientifically sound but the funding sources are not disclosed as far as I can tell.
One paper argued with big data that very few problematic cases are reported over many years. I can agree with that and so I can finish my bag of BTMS feeling at ease. And the damages that a 200 lb person vs a 300 lb person can do are very different.
Unfortunately, the 2nd paper said that the Behentrimonium ion concentration in the sediment off some bay is increasing exponentially over many years. Maybe that's the reason why BTMS isn't used in the conditioners that we have, good or bad.
So, derived from any plant is irrelevant, except for religious reasons that cannot be from animals. You need to find carbon chains somewhere, though killing plants is much better than from fossils. And it's too easy to be an organic compound after heavy chemical processing. An organic compound is made up of carbon, hydrogen, oxyen, and nitrogen etc. If it's organic, it is biodegradable in theory. But in real life, BT is organic but accumulates in the environment.
The word is readily biodegradable; a high percentage will degrade in days or months. And if it's a naturally occurring organic compound found in living things, I bet it is readily biodegradable.
And most things like surfactants and quats that change the property of water, such as tension and viscosity, must be toxic to aquatic life. It's like putting you into the atmosphere of some alien planets. If it's readily biodegradable, it may be reduced in waste treatment plants, and won't accumulate in the ocean.
The other thing is preservatives. Most of the chemicals can kill rats in high concentration. You are lucky if they are not preservative themselves. Others are self-preserving like glycerin, a sugar substitute. Since I only make a bottle of two at a time, if the thing doesn't go bad like food, I consider it preserved. And I'm not eating it.
And there is the myth about animal testing. If you put a new invented chemical into a product, you probably test it on animals instead of risking class action. But if you claim free of animal testing, does it mean that all the ingredients in the product are never tested on animals? This is almost impossible. Except for soap, it has been tested on humans for hundred of years, therefore no other test needed.
And the process is very simple. Melt 5% (weight) BTMS in a cup of 10% glycerin in a pan of hot water on a stove. Heat water in the microwave to about the same temperature or higher. Pour water into BTMS and stir. Done. It will be a white cream. The best rinse off detangler. You can add a few drops or a spoon of oil of your choosing. Also, one or two drops of essential oil for the fragrance.
Next time I'll try hydrolyzed guar gum that is like a quat.
One paper argued with big data that very few problematic cases are reported over many years. I can agree with that and so I can finish my bag of BTMS feeling at ease. And the damages that a 200 lb person vs a 300 lb person can do are very different.
Unfortunately, the 2nd paper said that the Behentrimonium ion concentration in the sediment off some bay is increasing exponentially over many years. Maybe that's the reason why BTMS isn't used in the conditioners that we have, good or bad.
So, derived from any plant is irrelevant, except for religious reasons that cannot be from animals. You need to find carbon chains somewhere, though killing plants is much better than from fossils. And it's too easy to be an organic compound after heavy chemical processing. An organic compound is made up of carbon, hydrogen, oxyen, and nitrogen etc. If it's organic, it is biodegradable in theory. But in real life, BT is organic but accumulates in the environment.
The word is readily biodegradable; a high percentage will degrade in days or months. And if it's a naturally occurring organic compound found in living things, I bet it is readily biodegradable.
And most things like surfactants and quats that change the property of water, such as tension and viscosity, must be toxic to aquatic life. It's like putting you into the atmosphere of some alien planets. If it's readily biodegradable, it may be reduced in waste treatment plants, and won't accumulate in the ocean.
The other thing is preservatives. Most of the chemicals can kill rats in high concentration. You are lucky if they are not preservative themselves. Others are self-preserving like glycerin, a sugar substitute. Since I only make a bottle of two at a time, if the thing doesn't go bad like food, I consider it preserved. And I'm not eating it.
And there is the myth about animal testing. If you put a new invented chemical into a product, you probably test it on animals instead of risking class action. But if you claim free of animal testing, does it mean that all the ingredients in the product are never tested on animals? This is almost impossible. Except for soap, it has been tested on humans for hundred of years, therefore no other test needed.
And the process is very simple. Melt 5% (weight) BTMS in a cup of 10% glycerin in a pan of hot water on a stove. Heat water in the microwave to about the same temperature or higher. Pour water into BTMS and stir. Done. It will be a white cream. The best rinse off detangler. You can add a few drops or a spoon of oil of your choosing. Also, one or two drops of essential oil for the fragrance.
Next time I'll try hydrolyzed guar gum that is like a quat.
Thursday, January 26, 2017
Review of Parental Control Apps for mobiles and more
I was frustrated looking for a working and useful parental control app for all the smartphones and tablets. Now, after the work is done, I am getting back at some of them. Here is the review:
First, my aim is to monitor and limit usage of the phone when I am not around. I'm not interested in web content filtering because doing it well on the phone will be difficult. The home router and cloud filter are the better choices. My kids won't spend a lot of time away from home and alone.
Project Fi data only SIM
This may be the world's first use of this SIM as a parental control. And this is the hail Mary strike when nothing else works. On the phone of the Project Fi account, you can "remove" the data-only SIM from the account instantly via the Project Fi app. The SIM is disabled instantly. And when you want to reenable the SIM instantly, you can just do the same when you first activate the SIM.
To activate the SIM, you go to fi.google.com/data and enter the activation code that comes with the SIM. That's it. It doesn't matter who orders the SIM. If you activate the SIM on your fi account, it's yours. There is an activate by date about a year in the future. I suppose you can remove and activate the SIM for an unlimited number of times before that date. Just don't lose the activation code.
The data-only SIM works for all phones and tablets that can use a T-MO SIM. Yes, it works for android phones and iPhones too, either locked to the T-MO network or unlocked. Though, you need a normal Fi SIM with talk and text on a Fi approved phone. It may be worthwhile to have a Fi phone for parental control, even if all your devices are with iOS.
On phones, you need either a dual-SIM phone or use a VOIP app. One of the Amazon exclusive phones is a dual-SIM one perfect for kids. For VOIP, the best is Hangout because you can have a phone number like everybody else. Nobody knows you are using VOIP; people dial your number and see your caller ID. In the latter case, it is more awesome as you not only take away all 4G data privilege, but also the ability to talk and text.
Dinner Time Plus
It works but only for Android. Once there was an app on iOS but it was only for monitoring the kids. The one off price model is right, making it the cheapest of all other parental apps. You can set arbitrary schedules to block the phone and you can set time limits for all or individual apps at other times. You can also whitelist or blacklist individual apps. You also have the history of apps the kids use.
The newer apps depend on admin privilege and if you ban the settings app, it would be rather difficult to hack to bypass the parental control.
Screen Time
This one is truly multiplatform, working for Android and iOS. Schedule works and time limit works. But the critical deficiency is that you have only a bedtime schedule and a school time schedule. Unbelievable! The school time schedule is enforced only for weekdays. You can pick the weekdays to enforce the bedtime schedule but you can only have one schedule. Really, I couldn't care less about any other feature requests. I don't see why they cannot do that because they have already done it. Just allow multiple "bedtime" schedules and you are done. The only reason I can think of is that the only programmer had left.
On iOS, there is the device profile similar to admin privilege in android. The profile is protected by the passcode so you should keep the tablet unlocked for kids to use. You should also ban the "deletion" of apps via the iOS restriction options. On Android, they once used a non-approved method to prevent bypassing. You have to load a special version outside of the Play store.
I'm still using it for iPad. Phones are difficult if you can't have enough schedules. iPad's are easier as you don't need it to call home. If you don't have a schedule for the day, you still have time limits.
kidslox
Locking the iPad is a sure thing on arbitrary schedules. But the time limit doesn't work on it. I was told that kidslox need to run in the background to monitor time limits. But first, my ipad 4 doesn't have the multitasking option to enable or disable and the background refreshing option is on. Even if my iPad has multitasking, restarting it or crashing it deliberately would likely kill the app in the background.
OurPact
Looks good but parents are limited to iOS. I didn't even try.
Family Time
Looks perfect. But the pricing and web pages looked like a design by a scammer. Claim discount? You have to pay for the whole year. Free Trial? You have to pay for the whole year still, though you have the first day free! Is that some new marketing strategies you learn from colleges nowadays? I'm so out of touch! Nowhere at the website says how to get a refund before the free trial ends. Pass.
MMGuardian
This is the earlier one and much more expensive at the time. If I know that it is so much cheaper now, I might have tried again. I did go through the 14 day free trial and then on and off after that on the free plan. The problem is - it's two complicated. I just need to monitor what my kids are doing and if I am not around, I want to enforce automatically bedtime and study time. Having time limits and control on an individual app is a plus, allowing a more flexible schedule. The complicated menu when you turn on the app is a big deterrent. Now, things may be a lot different now and it is.
But still, the list of functions is long and the pricing is complicated. Gone are the deal maker training with more useful things added such as GPS.
Think about it, if everything works perfectly, why are the other apps still around?
getScreen
Another cross platform app. But I can't install it on the iPad. It would enter a loop if I already have a device profile (admin privilege) installed. Even if I cleared and uninstall everything, the loop still goes on.
First, my aim is to monitor and limit usage of the phone when I am not around. I'm not interested in web content filtering because doing it well on the phone will be difficult. The home router and cloud filter are the better choices. My kids won't spend a lot of time away from home and alone.
Project Fi data only SIM
This may be the world's first use of this SIM as a parental control. And this is the hail Mary strike when nothing else works. On the phone of the Project Fi account, you can "remove" the data-only SIM from the account instantly via the Project Fi app. The SIM is disabled instantly. And when you want to reenable the SIM instantly, you can just do the same when you first activate the SIM.
To activate the SIM, you go to fi.google.com/data and enter the activation code that comes with the SIM. That's it. It doesn't matter who orders the SIM. If you activate the SIM on your fi account, it's yours. There is an activate by date about a year in the future. I suppose you can remove and activate the SIM for an unlimited number of times before that date. Just don't lose the activation code.
The data-only SIM works for all phones and tablets that can use a T-MO SIM. Yes, it works for android phones and iPhones too, either locked to the T-MO network or unlocked. Though, you need a normal Fi SIM with talk and text on a Fi approved phone. It may be worthwhile to have a Fi phone for parental control, even if all your devices are with iOS.
On phones, you need either a dual-SIM phone or use a VOIP app. One of the Amazon exclusive phones is a dual-SIM one perfect for kids. For VOIP, the best is Hangout because you can have a phone number like everybody else. Nobody knows you are using VOIP; people dial your number and see your caller ID. In the latter case, it is more awesome as you not only take away all 4G data privilege, but also the ability to talk and text.
Dinner Time Plus
It works but only for Android. Once there was an app on iOS but it was only for monitoring the kids. The one off price model is right, making it the cheapest of all other parental apps. You can set arbitrary schedules to block the phone and you can set time limits for all or individual apps at other times. You can also whitelist or blacklist individual apps. You also have the history of apps the kids use.
The newer apps depend on admin privilege and if you ban the settings app, it would be rather difficult to hack to bypass the parental control.
Screen Time
This one is truly multiplatform, working for Android and iOS. Schedule works and time limit works. But the critical deficiency is that you have only a bedtime schedule and a school time schedule. Unbelievable! The school time schedule is enforced only for weekdays. You can pick the weekdays to enforce the bedtime schedule but you can only have one schedule. Really, I couldn't care less about any other feature requests. I don't see why they cannot do that because they have already done it. Just allow multiple "bedtime" schedules and you are done. The only reason I can think of is that the only programmer had left.
On iOS, there is the device profile similar to admin privilege in android. The profile is protected by the passcode so you should keep the tablet unlocked for kids to use. You should also ban the "deletion" of apps via the iOS restriction options. On Android, they once used a non-approved method to prevent bypassing. You have to load a special version outside of the Play store.
I'm still using it for iPad. Phones are difficult if you can't have enough schedules. iPad's are easier as you don't need it to call home. If you don't have a schedule for the day, you still have time limits.
kidslox
Locking the iPad is a sure thing on arbitrary schedules. But the time limit doesn't work on it. I was told that kidslox need to run in the background to monitor time limits. But first, my ipad 4 doesn't have the multitasking option to enable or disable and the background refreshing option is on. Even if my iPad has multitasking, restarting it or crashing it deliberately would likely kill the app in the background.
OurPact
Looks good but parents are limited to iOS. I didn't even try.
Family Time
Looks perfect. But the pricing and web pages looked like a design by a scammer. Claim discount? You have to pay for the whole year. Free Trial? You have to pay for the whole year still, though you have the first day free! Is that some new marketing strategies you learn from colleges nowadays? I'm so out of touch! Nowhere at the website says how to get a refund before the free trial ends. Pass.
MMGuardian
This is the earlier one and much more expensive at the time. If I know that it is so much cheaper now, I might have tried again. I did go through the 14 day free trial and then on and off after that on the free plan. The problem is - it's two complicated. I just need to monitor what my kids are doing and if I am not around, I want to enforce automatically bedtime and study time. Having time limits and control on an individual app is a plus, allowing a more flexible schedule. The complicated menu when you turn on the app is a big deterrent. Now, things may be a lot different now and it is.
But still, the list of functions is long and the pricing is complicated. Gone are the deal maker training with more useful things added such as GPS.
Think about it, if everything works perfectly, why are the other apps still around?
getScreen
Another cross platform app. But I can't install it on the iPad. It would enter a loop if I already have a device profile (admin privilege) installed. Even if I cleared and uninstall everything, the loop still goes on.
Thursday, November 24, 2016
Dual-phone method for self hair cutting
Of all the youtube videos, I still couldn't find one that uses smartphones as a back side mirror. If you do not do this, you do not have a full straight backside view of your haircut. Without this view, many cuts are not feasible.
The good thing about the dual-phone method is that it's free; you just need to find two phones to use for the duration of your hair cut. Tape one to the wall or bathtub tile with the back camera facing out. Use the other like a handheld mirror.
The apps to use are two-way video chats like facetime, hangout or skype, in which you just need one side of it. What I actually use is IPCam to turn the phone on the wall into a webcam. On the handheld, I use Tinycam for the display. They work together and both free.
The alternative is a hinged three-piece mirror found on youtube, costing a silly amount of money. Of course, you can do it yourself but phones cost nothing and you need to do almost nothing. Of the 3 pieces of mirror, you only need the two side mirrors. They cannot be too small that you have to get very close with a limited view. With a smartphone cam, you can see at any angle you like. For Tinycam, if you double tap the screen, the image will zoom into the point of contact.
You do need two decent phones with decent wifi connections or else there will be a lag between the actions and the image on the handheld phone. Though it's not a big deal if you only want to see the result after some cutting.
I tried something similar many years ago. I used an old camcorder as the back camera, attached to a portable DVD player with video input. It sort of worked but you really need a tall tripod to mount the camcorder. It's a bit of trouble to hold the screen and you can knock out the whole system anytime. It's not possible to do it in the bathtub, my favourite place for the ease of cleaning.
I forget all about it because I developed my way of self-hair-cutting and has been using it for a couple of years now. First, you need Flowbee since it is what hair stylists do for the most part. Then, you need a Philips trimmer designed for self-hair-cutting.
The Flowbee allows you to cut all your hair to the same length, without which you have to do it approximately with two hands, having to mount or hang the handheld screen onto somewhere convenient. Some new stylists have trick clips to do it more precisely; you can do it blind with the clips. Flowbee is for short hairs from a quarter of an inch to several inches, more suitable for men. Though, it's as clumsy as a dinasour when the vacuum is attached.
The trimmer head of the Philips can be rotated at any angle, so you don't need to twist your arms to trim your back hair. It has all the attachments so you can fade and blend if you know how to. It has been a couple of years now and still works like new.
My tip to get a straight horizontal endge at the back is to use a strip of velco, the tough side, wrapping half the head at the back, attaching to a rubber band to wrap around the head from the front. Wear the velco band from the top of your head. Slip the band down to the hairline where you want to cut and then use the trimmer.
The good thing about the dual-phone method is that it's free; you just need to find two phones to use for the duration of your hair cut. Tape one to the wall or bathtub tile with the back camera facing out. Use the other like a handheld mirror.
The apps to use are two-way video chats like facetime, hangout or skype, in which you just need one side of it. What I actually use is IPCam to turn the phone on the wall into a webcam. On the handheld, I use Tinycam for the display. They work together and both free.
The alternative is a hinged three-piece mirror found on youtube, costing a silly amount of money. Of course, you can do it yourself but phones cost nothing and you need to do almost nothing. Of the 3 pieces of mirror, you only need the two side mirrors. They cannot be too small that you have to get very close with a limited view. With a smartphone cam, you can see at any angle you like. For Tinycam, if you double tap the screen, the image will zoom into the point of contact.
You do need two decent phones with decent wifi connections or else there will be a lag between the actions and the image on the handheld phone. Though it's not a big deal if you only want to see the result after some cutting.
I tried something similar many years ago. I used an old camcorder as the back camera, attached to a portable DVD player with video input. It sort of worked but you really need a tall tripod to mount the camcorder. It's a bit of trouble to hold the screen and you can knock out the whole system anytime. It's not possible to do it in the bathtub, my favourite place for the ease of cleaning.
I forget all about it because I developed my way of self-hair-cutting and has been using it for a couple of years now. First, you need Flowbee since it is what hair stylists do for the most part. Then, you need a Philips trimmer designed for self-hair-cutting.
The Flowbee allows you to cut all your hair to the same length, without which you have to do it approximately with two hands, having to mount or hang the handheld screen onto somewhere convenient. Some new stylists have trick clips to do it more precisely; you can do it blind with the clips. Flowbee is for short hairs from a quarter of an inch to several inches, more suitable for men. Though, it's as clumsy as a dinasour when the vacuum is attached.
The trimmer head of the Philips can be rotated at any angle, so you don't need to twist your arms to trim your back hair. It has all the attachments so you can fade and blend if you know how to. It has been a couple of years now and still works like new.
My tip to get a straight horizontal endge at the back is to use a strip of velco, the tough side, wrapping half the head at the back, attaching to a rubber band to wrap around the head from the front. Wear the velco band from the top of your head. Slip the band down to the hairline where you want to cut and then use the trimmer.
Saturday, November 5, 2016
Scheduled blocking of websites using cheap routers
Searching for how to block Facebook on a schedule, you can see how complicated it is. Actually, just blocking a site like this is complicated by itself because of the many IP's it could use.
You may want to block youtube, gaming and social time-wasting websites, but allow two hours of access in the evenings every day. The amount of IP's to deal with is phenomenal. Also, nowadays many sites use the https protocol so URL-based blocking won't work. Somebody set up a proxy server on an old laptop to filter the web contents, but both the installation and maintenance are troublesome.
I find the DNS based solution very simple. In DD-WRT, a line in the /tmp/hosts file can block the whole site:
10.0.0.1 www.youtube.com
where a non-reachable IP is assigned to the external website. So you just need two versions of the hosts file, and restart the DNS service dnsmasq after the file is changed. Then you need two scripts as cronjobs, for example:
0 22 * * * root sh /tmp/stop.sh
0 20 * * 1-4 root sh /tmp/go.sh
0 19 * * 0,5,6 root sh /tmp/go.sh
At 22:00 every day, youtube and others sites are blocked. On weekdays except for Friday, movie time starts at 20:00, but earlier on other days at 19:00. The schedule can be entered via GUI on the Administration > Management > Cron box.
The "root" prefix is the one thing that I hate developing anything for dd-wrt. Cookbook instructions are good enough for me. You need that to run the commands with root privilege, or it wouldn't work. Because of its limitations, it mostly does something different from Linux, even though the source codes have the same origin. There are full of landmines like this and the system can never be documented enough. Even if there are documents, the functions may not work on your build version because of different chipsets and manufacturers.
To modify the hosts files and 3-line scripts, save a startup script at the Administrations > Commands tab:
You may want to block youtube, gaming and social time-wasting websites, but allow two hours of access in the evenings every day. The amount of IP's to deal with is phenomenal. Also, nowadays many sites use the https protocol so URL-based blocking won't work. Somebody set up a proxy server on an old laptop to filter the web contents, but both the installation and maintenance are troublesome.
I find the DNS based solution very simple. In DD-WRT, a line in the /tmp/hosts file can block the whole site:
10.0.0.1 www.youtube.com
where a non-reachable IP is assigned to the external website. So you just need two versions of the hosts file, and restart the DNS service dnsmasq after the file is changed. Then you need two scripts as cronjobs, for example:
0 22 * * * root sh /tmp/stop.sh
0 20 * * 1-4 root sh /tmp/go.sh
0 19 * * 0,5,6 root sh /tmp/go.sh
At 22:00 every day, youtube and others sites are blocked. On weekdays except for Friday, movie time starts at 20:00, but earlier on other days at 19:00. The schedule can be entered via GUI on the Administration > Management > Cron box.
The "root" prefix is the one thing that I hate developing anything for dd-wrt. Cookbook instructions are good enough for me. You need that to run the commands with root privilege, or it wouldn't work. Because of its limitations, it mostly does something different from Linux, even though the source codes have the same origin. There are full of landmines like this and the system can never be documented enough. Even if there are documents, the functions may not work on your build version because of different chipsets and manufacturers.
To modify the hosts files and 3-line scripts, save a startup script at the Administrations > Commands tab:
cp /tmp/hosts /tmp/hosts.go echo "10.0.0.1 www.youtube.com">>/tmp/hosts cp /tmp/hosts /tmp/hosts.stop echo "cp /tmp/hosts.go /tmp/hosts"> /tmp/go.sh echo "stopservice dnsmasq" >> /tmp/go.sh echo "startservice dnsmasq" >> /tmp/go.sh echo "cp /tmp/hosts.stop /tmp/hosts" > /tmp/stop.sh echo "stopservice dnsmasq" >> /tmp/stop.sh echo "startservice dnsmasq" >> /tmp/stop.sh
Basically, it's adding one line per website on the hosts file to be blocked.
The blocking is not necessarily immediate because of the browser cache. My observation shows that the cache expires in a few minutes at most. That means if you have been watching youtube movies less than a few minutes when the blocking starts, you may still be able to access youtube for a few more minutes. Once you stop accessing youtube for a few minutes, you cannot access it again during blockage hours. I doubt if that makes a loophole. But this can easily be plugged by enforcing a total internet ban for a few minutes, for only those IP's assigned to kids.
Now, the blockage affects everybody using the router as the DNS nameserver. For adults, you can use public servers such as the google ones at 8.8.8.8. You have to do it on every adult machine. For the kids' machines, you can use the DD-WRT access restrictions to block port 53, so all DNS requests are rejected if they try to hack, forcing the default name server 192.168.1.1 to be used. To select the affected machines, only the IP range works on my version of DD-WRT.
MAC-based restrictions mostly don't work on my version. So I have to use Static Leases on the Services tab to assign IP's to machines by their MAC's. It should be noted that it is rather easy to change IP's on any machine to defeat blocking. A simple solution will be a script to police the lease table at regular intervals and send me an email if the same MAC has other IP's assigned. It would be rather painful to develop on the router but a lot less hassle using an old laptop with Linux installed.
I also use OpenDNS for the underlying web filter. It's about the only DNS filter that allows you to customize categories to block, to whitelist and blacklist. For example, I disable all search engines but whitelist Google. So I can concentrate on getting the SafeSearch mode working on Google. The same way I disable all video sharing sites but whitelist youtube, so I can concentrate on making the restricted mode work. The router is setup to allow these sites through. Once they are working fine, I can block each site with a line in the hosts file.
The other interesting approach I tried is to install a parallel DNS nameserver on an old laptop with Linux installed, on the same wifi network. It is trivial to install Dnsmasq and works in no time. You just need to point to that machine IP for the DNS nameserver. It's the same Dnsmasq on DD-WRT but on a more powerful machine, with lots of memory and hard disc space. More fancy things can be done but the blocking above can be done by two static hosts files, one on the router and one on the Linux machine. You just need to change the nameserver file at the router, for the request to either go straight to OpenDNS or via the Dnsmasq at the laptop. But you have to make sure that the hard drive is not constantly used. The /tmp directory in dd-wrt is a RAM drive.
0 22 * * * sh /tmp/stop.sh 0 20 * * 1,2,3,4 sh /tmp/go.sh 0 19 * * 0,5,6 sh /tmp/go.sh
Sunday, October 30, 2016
Best Web Content Filtering using a cheap WIFI Router
OpenDNS is great for web content filtering, but it cannot enforce safe search nor youtube restricted mode. Of course, you can disable all search engines and all video sites.
Google did provide a mechanism via DNS to enforce safe search and restricted mode on your network, which OpenDNS cannot implement. The solution is DD-WRT. You can buy a WIFI router with DD-WRT as the OEM software. Somebody sells routers preinstalled with it, or you can replace the OEM software yourself.
The router can be very cheap. You don't need to give up your current super duper routers. You just need one DD-WRT router to be the final gatekeeper to the internet. You just need fast switching and a higher bandwidth than your ISP link.
Inside DD-WRT, under the Services tab, you can add the following to the additional DNSMasq options:
address=/www.google.com/216.239.32.20
address=/www.youtube.com/216.239.38.120
address=/m.youtube.com/216.239.38.120
address=/youtubei.googleapis.com/216.239.38.120
address=/youtube.googleapis.com/216.239.38.120
address=/www.youtube-nocookie.com/216.239.38.120
That is all! Being DD-WRT, I would be very careful about extra spaces. The 1st line redirects to the IP of forcesafesearch.google.com. The rest are Google's instructions to redirect to the IP of restrict.youtube.com. You can also redirect to 216.239.38.119, the IP of restrictmoderate.youtube.com.
Google did provide a mechanism via DNS to enforce safe search and restricted mode on your network, which OpenDNS cannot implement. The solution is DD-WRT. You can buy a WIFI router with DD-WRT as the OEM software. Somebody sells routers preinstalled with it, or you can replace the OEM software yourself.
The router can be very cheap. You don't need to give up your current super duper routers. You just need one DD-WRT router to be the final gatekeeper to the internet. You just need fast switching and a higher bandwidth than your ISP link.
Inside DD-WRT, under the Services tab, you can add the following to the additional DNSMasq options:
address=/www.google.com/216.239.32.20
address=/www.youtube.com/216.239.38.120
address=/m.youtube.com/216.239.38.120
address=/youtubei.googleapis.com/216.239.38.120
address=/youtube.googleapis.com/216.239.38.120
address=/www.youtube-nocookie.com/216.239.38.120
That is all! Being DD-WRT, I would be very careful about extra spaces. The 1st line redirects to the IP of forcesafesearch.google.com. The rest are Google's instructions to redirect to the IP of restrict.youtube.com. You can also redirect to 216.239.38.119, the IP of restrictmoderate.youtube.com.
These settings are independent of OpenDNS, but much better with it. At the OpenDNS settings, you should disable search engines and video sharing. Then you whitelist, never block, just google and youtube:
forcesafesearch.google.com
google.com
youtube.com
Unfortunately, if your kids are smart enough to bypass the DNS on the router, you have to be smarter to disable their DNS request. In DD-WRT, it's under the Access Restrictions tab. You add a policy that filters out some services. You select dns under the Blocked Services section.
Under the list of clients, you should enter all phones, computers, and tablets that access the internet. You can use MAC's, IP's or range of IP's.
The most important warning for DD-WRT is that what you see may not all work! There are multiple underlying chipsets that are not compatible. The software is probably written and tested by very few people. In brief, buy a recommended model, and flash only the recommended DD-WRT version.
For my DD-WRT, access restrictions on MAC and IP all don't work. Only a range of IP's work. MAC's are unique for each machine but IP's can change with automatic assignments by DHCP. You can map MAC's to IP's in a central place under the Services tab, DHCP Server, Static Leases.
Enjoy!
Monday, May 30, 2016
Window Tint Removal Using Steam
I tinted the car window myself using the very popular Gila product. I did the windows in my home but car windows is a different animal. I did it badly but let it hanged on for a year. Because I thought it's difficult to take it out with glues on. I brought the Gila remover but it sat in the garage.
To save time and to not touching chemicals, I brought it to a tint shop. Because retinting it would take a few minutes for them for cheap. But the problem is, to remove the tint it could take up to 3 hours! It would be the worse case I suppose, with professionally installed tint with super duper glue. Since I didn't have 3 hours, I passed.
Luckily I consulted the internet. Steam is the word. It made a lot of sense. I already have a big steamer with a lot of accessories. I didn't even remember the capacity but I put in 1 L or 1 Q of water, the steam last for hours. Still I waited and waited for a suitable day. If I messed it up again like when I put the tint up, I would leave a lot of strange things on the windows and my kids won't want to ride in it.
But it was so darn easy. I should have watched the million view video. It is easier than that. I would think the DIY tints are easy. But I think his tint were professionally done. So I suppose all the glues are about the same.
My contribution: Open the car door widely and steam from an angle so all the steam goes out of the car. My steamer is professional grade. I use a pointed nozzle so it's all steamy even outdoors.
Open the window slightly and start steaming from the top. First, tape a plastic bag on the bottom of the window so water slides down onto the ground and not the door. Tape on the window so the tapes and the bag will go with the tint when it's removed.
My top edge is already peeling off so that's where I started. You may start from the corner if that comes out first, or like the guy in the video, make a cut in the middle so you have a corner of the tint to start with.
I point the steam from the top, aiming at the meeting point between the tint and the glass, while I pull the tint down. If you don't have a pointed nozzle, you may have to steam around the edge.
If the tint breaks up into two, you can carry on one side at a time. If the tint stays in one piece, you pull and steam at the same time one corner, then the other, then the middle. Pull gently all the time. If the tint is steamed enough, you will feel that it's easy to pull. And when you feel that it's harder and harder, steam more.
Never saw and had any problem with residue or glues.
It also depends on how the tint is installed. The instructions I got was to leave a lot of margins on the sides and the bottom. But that was killing my installation. I just couldn't get those margins into the sides and bottom of the window. And since I have an exact template of the window, I should have left a very thin margin. It's easy to go into the window frame and there will not be visible gaps.
Maybe next time I use static clint films.
To save time and to not touching chemicals, I brought it to a tint shop. Because retinting it would take a few minutes for them for cheap. But the problem is, to remove the tint it could take up to 3 hours! It would be the worse case I suppose, with professionally installed tint with super duper glue. Since I didn't have 3 hours, I passed.
Luckily I consulted the internet. Steam is the word. It made a lot of sense. I already have a big steamer with a lot of accessories. I didn't even remember the capacity but I put in 1 L or 1 Q of water, the steam last for hours. Still I waited and waited for a suitable day. If I messed it up again like when I put the tint up, I would leave a lot of strange things on the windows and my kids won't want to ride in it.
But it was so darn easy. I should have watched the million view video. It is easier than that. I would think the DIY tints are easy. But I think his tint were professionally done. So I suppose all the glues are about the same.
My contribution: Open the car door widely and steam from an angle so all the steam goes out of the car. My steamer is professional grade. I use a pointed nozzle so it's all steamy even outdoors.
Open the window slightly and start steaming from the top. First, tape a plastic bag on the bottom of the window so water slides down onto the ground and not the door. Tape on the window so the tapes and the bag will go with the tint when it's removed.
My top edge is already peeling off so that's where I started. You may start from the corner if that comes out first, or like the guy in the video, make a cut in the middle so you have a corner of the tint to start with.
I point the steam from the top, aiming at the meeting point between the tint and the glass, while I pull the tint down. If you don't have a pointed nozzle, you may have to steam around the edge.
If the tint breaks up into two, you can carry on one side at a time. If the tint stays in one piece, you pull and steam at the same time one corner, then the other, then the middle. Pull gently all the time. If the tint is steamed enough, you will feel that it's easy to pull. And when you feel that it's harder and harder, steam more.
Never saw and had any problem with residue or glues.
It also depends on how the tint is installed. The instructions I got was to leave a lot of margins on the sides and the bottom. But that was killing my installation. I just couldn't get those margins into the sides and bottom of the window. And since I have an exact template of the window, I should have left a very thin margin. It's easy to go into the window frame and there will not be visible gaps.
Maybe next time I use static clint films.
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