hydrogen peroxide, am I missing something?

[myfordcnc]

I thought stronger solutions can make the parts chalky, heat definately makes a difference as it opens the pores of the nylon. Also using a BBQ tray or making a tin foil dish helps collect the rays.

I find leaving them outside on a full or near full moon makes a difference too.

Remember too peroxide is sensitive to light and can go off (reason it's stored in dark bottles). Might try getting some fresh stuff and trying again.

Also many people over whiten parts which looks wrong. Should be more ivory then white.

I must say i really like the white white. No idea what it is doing to the actual plastic but i like the look. But yeah probably not very authentic.

[THE H.P FREAK]

HI!... Something doesn't sound right. I have no problems whitening white plastic parts. The key is a true UVB light. I have found putting it out in the sun light is a slow process. This is my set-up :

- a Repti-glo 26 watt 10.0 UVB light bulb (find this in local pet supply stores).
- Aluminum foil ($1 store).
- Glass bowls , not plastic. ($1 store).
- Small desk lamp preferably with a flexible goose neck.
- Hydrogen peroxide 3% ($1 store)

Take aluminum foil and wrap the glass bowl with the shiny side inwards. This will help reflect the light. Put the parts in the bowl. Fill the bowl with H/P. Make sure to fill a good amount above the parts. Shake parts with small screwdriver to release air bubbles that stick to the parts. This allows them to sink. Take UVB light and install in lamp. Place lamp just inches off the top of the H/P solution. I then wrap a cone of aluminum foil from the bowl to the top of the lamp to concentrate the UVB light even more. 9shiny side inwards) I usually let the light go for about 3-7 days depending how yellowed the parts are. You will need to top off the H/P solution occasionally due to evaporation from the heat of the lamp. Also you need to stir and shake the parts to get rid of air bubbles caused by the chemical reaction of the whitening process. Also rotate the parts frequently.

BTW guys have done different set-ups over the years. Stronger H/P solution has no effect.

[spennyy2k]

Yeah the parts just don't seem to have lost the yellow at all. Will give it another go

[THE H.P FREAK]

HI!... I have found the using the H/P by itself does nothing much. Using a UVB light does nothing much. They have to be used together for the process to work.

[Lowgear]

Summer is coming so 90-100 deg days are only a month or two off so I'll see if some heat helps the process.

Must be nice... I won't see those kind of temperatures for another 4+ months. I'm not too jealous though because I hate when it gets that hot. The problem here is all summer long the humidity hovers around 135%. I've been to Nevada before where the temperature was something way above a hundred and it felt like nothing due to being a dry heat.

Also many people over whiten parts which looks wrong. Should be more ivory then white.

Yeah, don't bleach the heck out of the parts as not only does it look bad (to some) it's incorrect.

[VintageFanatic]

H.P Freak's method here works great. I've found that only the most neglected, yellowed parts need a second round of cleaning.

[terry.sc]

Yeah the parts just don't seem to have lost the yellow at all. Will give it another go

The problem you have is you are here in the UK in winter, the sunlight isn't strong enough to do the job and won't be strong enough for some time. Looks like you are going to have to go for a UVB bulb.

[spennyy2k]

Yeah. I'm gonna go bulb hunting tomorrow

[THE H.P FREAK]

HI!... Look in the reptile section of your local pet store. I paid about $22 for mine.

[spennyy2k]

The nearest shop to me that stocks them is £25, which if I'm right works out at $41?

[spennyy2k]

You need the 10.0 one

[THE H.P FREAK]

HI!... I used this one :

[bully]

Yeh here in Perth Australia 38 degrees celsius out in sun in jar with only 3% chemist supermarket stuff and it works a treat mostly from the sunlight i would say uv index has been extreme.. One thing i have noticed is it goes off after a while and no matter what the uv or sunlight or heat is it doesn't do a lot.. My latest stuff outside today in 38 deg stinking hot temps give it a shake every hour or so an open cap slightly and the bubbles are like a spa bath seriously working a treat and that is 3%...If you don't get serious bubbling when agitated it is either the poor weather or off peroxide..

[Sixtysixdeuce]

I thought stronger solutions can make the parts chalky

That'll happen regardless of solution strength if the parts are deteriorated, namely from long term UV exposure. If you can scratch it with your fingernail and see a mark, it's going to chalk out during whitening. A part with good integrity will turn out fine, whether it spends several days in 3% or a few hours in 50%.

Remember too peroxide is sensitive to light and can go off (reason it's stored in dark bottles).

If memory serves, the strength must be greater than 76% for there to actually be an explosion hazard. Weaker solutions simply break down very quickly.

[klavy69]

There is also the 'yellowing' that you just can't get out with peroxide. You might have some of that stuff. Every once in awhile I get something with a yellow on it that almost acts as if its dyed that dark ivory color. Was there ever a color of dye called 'dirty oily yellow'? I can put some other items in with that other stuff from another car and they will whiten while the yellowed stuff still don't clean up.

You don't need anything over 3% with a good glass jar and sunlight...or artificial light if it means that much to you to add the expense of it.

Todd