Show me your soak tank

I am wondering what other people are doing to soak flux off of whole bikes. At UBI they had a large ultra sonic cleaner that made quick work of excess flux. That is not in the cards for me but I wonder what others are doing.

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I just put mine in the shower with the highest water temp and let them sit for a few minutes. Seems to get the flux off pretty well, I take a wire brush to the stubborn bits if they don’t wash off easily. Obviously if you really care about your shower you might not want to do this but as a college student…it works. Garbage cans left out in the rain also do the trick. As does a quick pour of boiling water if you only have a few spots of flux.

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I used the local canal , not the best solution

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this is really funny. I feel bad for the fishes, but I was like “they can’t possible be putting it into a lake or something, right?”

Hope you never loose a frame by accident!

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So far so good. I was a bit worried , the canal is a 5 min walk from workshop.
I left it there for an hour or so

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I don’t have a photo handy, but I grabbed a 22L Vevor ultrasonic cleaner for this. I don’t really have a good sink in my shop so that was kinda the only option. I have cleaned several frames in my bathtub too!

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I made a simple frame from 2 x 4 lumber and seal with a tarp. Cold water works, just takes an hour or so.

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I use one of those ‘under bed’ storage bins for bars / forks, but still use my tub at home for frames. A quick wipe of CLR after keeps the tub looking nice ahaha

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I use only the finest modern technology;

Bonus points; this one is Halloween-themed!

I used to use one of those under-bed storage bins too, they do fit frame shapes much better. But I had one too many disasters of accidentally creating a wave pool trying to move it around the shop to empty and making a huge mess so I went back to the trusty bucket.

A regular bucket can get you a long way but depending on the geo/frame size there’s always some part that doesn’t fit great. I keep a flux-water-only electric kettle in the shop and for these tricky spots I just wrap in wet rags, boil a kettle and pour over, and it’s good to go in ~10 min.

I’d like to weld up a narrow/upright frame sized aluminum soak tank with a drain spout on the bottom and casters and maybe a heating element too. But it would be a few hundred bucks in sheet and parts and who has the time to do these things. add it to the never ending list of shop projects!

I also don’t have running water in the shop so that makes things tricky especially in the winter. I have dreams of installing a huge rainwater tank outside, plumbing it in through an on-demand water heater into a basic tap/laundry basin type setup and then out to a grey water tank. BUT same deal as the above paragraph, I think this one is probably even more of a pipe dream :sweat_smile:

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For small jobs I use a stainless pot and an old laboratory hot plate. Hot water makes the flux go away faster.

For frames, I use an old laboratory water bath coliform incubator. It’s a stainless tank with a heater in the bottom and a circulation pump. Originally, it was set to regulate the temperature at precisely 44.5* C, but I have bypassed the control circuit. It would probably boil the water if I let it run long enough, but usually the frames are clean before it gets close.

Both of these were free. Make friends with the lab people.

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I am curious about your thoughts about ultrasonic tube cleaning. We have considered getting one of these giant ultrasonic cleaners

This is not really for a soak tank, but can be used for degreasing and prepping tubes: Budget Stainless Steel Parkerizing Tank, Gunsmith, blueing 40"x6"x6", 1/2" valve | eBay

They make a heated version, which just has a submerged heating element: Electric Steam Base – Big Jim's Parkerizing and Bluing

This lead me down the rabbit hole of immersion heaters

There are also these parts cleaner/ submersible pumps brushes:

Most of these ideas are probably overkill, but time saved is more time enjoying life :smile:

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I use a utility (basement) sink with a bucket heater. The bucket heater lets me keep the sink at 140-150f which melts flux really fast and saves me a lot of water. However holding water in the sink does leave some rust stains.

I can’t fit the whole frame, but I can usually figure out ways to rotate it so that it fits. A submersible aquarium pump can put a temporary stream on any joints that don’t fit.

This is a bucket heater, it’s just a submersible heating element:

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Haven’t tried it myself but read about this person using a Steam cleaner
Always thought about giving it a go.

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I built this stand for a sink and have a sous vide immersion heater to heat the water to temp. (So fancy, I know!) I don’t have running water at my shop, so I fill the sink with buckets from a spigot across the parking lot. The sink is big enough to submerge one main joint of a frame and I have a pump to help reach areas slightly above water level. For a full-frame soak, I still use the venerable home bathtub. Can’t beat it! However, I do have dreams of building a tank that’s proportioned for soaking an entire frame.


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I have a plastic horse trough. You can find them online or at a farm store outside of the city. A little bit pricy, but mine I can dunk the entire frame in. I think that hot water works better for removing flux. If I had to do it over, I might just go to a Walmart or a sporting goods store and buy a plastic kiddie pool.

I’m new here, and I thought I would start by posting to the most important thread on the site! I’ll make an introduction post at some point, but here’s my soak tank:

It is made from a 2x12 and some scrap plywood, and waterproofed with self-leveling epoxy (sold as a bar-top finish, but i think any cheap thin epoxy would work fine). The epoxy took forever to dry and kept slumping when i impatiently rotated it to do the next face, but other than that it was pretty straightforward.

I use a cheap ~1000w immersion heater to heat the water.

It’s kinda ugly, but probably better than using the bathtub!

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Welcome! That immersion heater looks nice. Do you have a link to it? How long does it take to heat the water?

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Thanks! This is the immersion heater I am using: https://www.amazon.com/gp/product/B0BPGD3K62/ref=ppx_od_dt_b_asin_title_s00?ie=UTF8&psc=1

The outlet I am using does not have a GFCI, so I deliberately choose an immersion heater which has ground fault protection. My impression is that these things can zap you if they fail in the wrong way.

It takes about 3 or 4 hours to raise the water temperature to 160f. I did notice that the water in the tank stratified (the water at the bottom of the tank never really warmed up). I could fix this by placing the element at the bottom of the tank, but I’m not sure I trust it to be be submerged… If I was doing it again, I would consider just adding a fitting for a water heater element towards the bottom of the tank, and adding the GFCI to the outlet. I think standard water heater elements are 1" npt.

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I believe it would be cheaper to build your own ultrasonic cleaner given the sizes at play, you can use an ultrasonic transducer glued to the back or side of the tank to generate the vibrations, it could even be a removable item that you can place on different tanks for different uses. Would be curious to know what it would take, transducers, arduino, some cables and a power supply?

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I have a large garbage can full of water and frankly it sucks. I usually end up using our utility sink inside the house.

I have been considering something like this RV water tank. I don’t know if there is enough structure left if I were to cut off the top but building a frame around it should fix that. The thickness is listed as “average 7/32” so should be thick enough to mount heater and agitation pump. New ones on ebay go for around $200 and it looks like it could hold 2 frames at a time. I wish I didn’t already have too many projects.