smontanaro 

I've pretty much decided I'm going to give my Automoto frame an oxalic acid bath. It seems to have plenty of refined petroleum products in the tubes though. What (if anything) should I use to try and degrease the inside of the frame before the oxalic acid treatment? Any suggestions for a good source for extra long bottle brushes?

clubman 

Maybe go at it differently. Do the OA bath but preserve those decades of grimy coating. Then blow in linseed oil to re-up the protection. Linseed was a popular treatment after WWII and might even be what's in there.
Can't remember whether you want boiled linseed or original flavour.

smontanaro 

Thanks. The frame has an oil port on the bottom bracket shell. Over the years, I'm sure plenty of oil and grease dissolved in oil has made its way in there. I can also see sand-like particles in the chainstays. I'd kinda like to get all that crud outta there and start from scratch. Also, it will help me better see in there (with a small USB borescope or similar) to decide if the frame is toast or worth repairing. To make matters worse, the frame was pinned during construction, so it will be a bit challenging to find a borsescope which I can squeeze past the pins. There are tons of cheap items on Amazon, but the length of the business end makes me worry they won't fit. Still thinking about that.

thinktubes 

Do a search on "dryer vent brushes" box boxes have lots of these

thook

do you not think the OA would pretty much contaminate the grease and any protection it might afford in the future?

clubman 

I think grease and this type of buildup would act as a barrier. OA is water based and would likely be repelled.

The OP's going to clean it right out just the same.

thook

okay. i just wondered since it's an acid. iow's, sodium lauryl sulfate is an acid compound and water based (dawn liquid soap), but cuts grease like mad. just like this product called "LA awesome" than can found at the dollar tree. except that's citrus based. anyway, i'm not a chemist enough, though, to know the differences

smontanaro 

We seem to be getting a bit off in the weeds. I want to be able to judge the soundness of the inside of the frame before deciding whether to do a significant restoration, and to have confidence that the frame is sound. Having gunk, dirt, rusty flakes, whatever in the tubes make it harder to investigate the frame. If I decide to keep the frame after rust removal and cleaning, I will certainly treat the inside with Boeshield, Frame Saver, or something similar. In addition, if petroleum products are even partially covering internal rust, then the OA won't be able to do its job properly. Finally, I have no idea how well-protected the tubes might currently be. If I clean it, derust, then treat it properly, I will have more confidence that the frame is ready for another 60 years of use.

thook

i mentioned that citrus "LA awesome" above. really great stuff. and, a spray bottle of it's....one whole dollar!! it rinses off really well, too. i mostly use it on the stove spills and splatters

Senior Ryder 00 

Hi,
My procedure has been first a liquid dish wash & scrub to get the grease/grime off. Rinse well before putting it in OA. Scrub any remaining rust spots with a plastic brush & OA. Safety glasses & gloves required, recommend plastic apron.
Cheers,
Van

OTS 

As above ^, I am usually delighted with the results that can be achieved with Dawn dish detergent. I think it highly effective and don't hesitate to use it and use it again if less than desirable results aren't achieved the first time. Allowing it some time to work before a rinse is key. It seems to get the job done without any harmful side effects.

bark_eater 

I'd start with mineral spirits, then a degreaser like simple green and then a water wash before the Oxalic acid. For cleaning inside the tubes I would use a handful of ball bearings along with what ever solution and and shake rattle and roll the frame to mechanically assist the cleaning. A little fore thought as to making sure you can get all the ball bearing out would be important, because having one rolling around the top tube when when your riding would drive me nuts.

oneclick 

The fix for rattlely bits that won't come out is glue. You figure out which tube has the bit, and arrange the bit to roll to a place close to whatever access you do have, and inject a squirt of glue (I use contact cement). If it's a vent hole make sure it's not plugged after.

AJI125 

I’ve got a set of appliance brushes from Home Depot - one was the larger 3” dryer vent brush and the other is a refrigerator brush, tapered from maybe 1”-1.5” diameter. Works great for bike tubes! Nice and stiff bristles get most of the crusty stuff out - make sure to twist the brush while you work to get the best results.

It’s flexible enough to get all the main tubes if they are fully open (as opposed to top tubes that often only have a small access hole each end), I’ve also bought a brush set off Amazon with different size brushes that fit in chainstay, but those were more hit or miss as they weren’t that stiff. I used some Dawn detergent and brushing and warm water rinsing before soaking a rusted on the insides Fuji. Worked like a charm.

I also pulled the frame halfway thru soak and used the same brush to loosen/dislodge the black buildup from Evaporust. Along with the typical “shakes” during soak to help things stuck inside move around (you can see the black muck shooting out vent holes if you do this). If you use OA that might not be necessary (never tried OA so not sure). Evaporust costs more but it does actually do a good job removing dirt and oil and such, just wastes some of the solution strength I believe.

Jeff Neese

There are any number of petroleum solvents that you could use to clean out the old gunk, prior to the OA bath. If you want to be super aggressive about it (and can maintain appropriate safety precautions), Naphtha or lacquer thinner would easily dissolve old grease and oil. Mineral spirits is a lot safer and would probably work just fine too.

RustyJames 

I’m on the side of dish soap, brushes and rinsing like crazy. If there is still some residue you literally wash, rinse, repeat until fully cleaned. OA bath, frame saver/Boeshield and your good to go.

My 2 cents…

smontanaro 

I got a dryer vent brush and a squirt bottle (for Simple Green) at Home Depot. The pins in the bottom bracket shell made quick work of the brush, but it did its job. Then it was off to the OA bath for a day or so. It came out pretty well.

machinist42

As previously mentioned in this thread, "LA's Totally Awesome" is a very effective water based degreaser. It does come in a Citrus Variant which will chew and discolour any Aluminum and isn't kind to chrome either. I suspect it's the "Citrus" bit.

I use "LA's Totally Awesome" in my ultrasonic cleaner, and when immersing grimy bits with rust, like freewheels, I add Oxalic Acid to the mix. I tested first in small controlled batches outside and with all the appropriate safety gear, and there does not appear to be any reaction. I use roughly a 10% "LA's Totally Awesome" concentration and add a couple tablespoons of Oxalic Acid and all the grime and rust are gone quite quickly.

I immerse stripped frames in a makeshift container fashioned from a bike box lined with a "Gorilla Bag" scrounged from Walmordor. They are inflatables used to fill empty spaces in transport trucks. I use a makeshift ultrasonic which admittedly is not the optimal frequency but seems to work well, which is an inexpensive immersible fog/mist producer. It has fancy lights too which are irrelevant, but kind of cool? I generally use more Oxalic Acid and less "LA's Totally Awesome" for frames because more rust and less grease.

Anyway, that's one solution to remove rust and degrease in a single operation?

Good luck!

(The Citrus "LA's Totally Awesome" may blow up when Oxalic Acid is added, I don't know. I have never tried the combination.)

(Congratulations on your successful operation. Sorry I was so late to the Party. I posted mostly for posterity.)

etherhuffer 

Also in the degreaser family are glycol ethers, best known as 409 Cleaner. Also, Tide washing detergents use surfactants that are good on grease as well.

smontanaro 

Based on aroma and effect on my lungs, my guess is that 409, Awesome, and Fantastyk (is it still around?). are all basically the same product.

cyccommute 

Sodium lauryl sulfate isn’t an acidic compound. It is the salt of an acid but it is itself neutral. It is an amphiphile which is a compound with a hypophilic ionic end and a lipophilic end meaning that part of it will dissolve in water (hypophilic end) and dissolve in fat (lipophilic end). In water, an amphilphilc compound will turn the water loving end outward and the fat loving end inward forming a micelle (basically a microscopic bubble). The fat loving end will dissolve fats from the water and hold them. The water loving end allows the fats to be carried in the water rather than ride on the top.

Oxalic acid doesn’t have the same ability. It’s too short and too acidic to be lipophilic. It complexes the iron oxide making it water soluble but it isn’t a micelle type mechanism.

etherhuffer 

If I remember correctly don’t surfactants with ring structures on the lipophilic end degrease better? I know that car wash surfactants are chosen for a certain amount of polarity as well, something to do with dirt that sticks to cars being attracted by the charge on the vehicle from air friction. The McKesson rep used to meet us at compounding businesses and discuss this stuff. Tailoring surfactants to end use is fascinating

cyccommute 

Some have ring structures but sodium lauryl sulfate is a straight chain alkane. It may coil but its molecular structure is straight.