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morrisman
26th Dec 2016, 04:41 PM
I recently bought a 20L tub of molasses , dirt cheap . I am pleasantly pleased with the results. Maybe the Summer heat has helped the process along .I used a strong mix maybe 4:1 water

The rusty parts are from a 1940 Morris army truck .

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.RC.
26th Dec 2016, 04:52 PM
Yes it works like magic. I do not think a strong brew makes any difference over a 10:1 mix.
Grahame Collins
26th Dec 2016, 07:02 PM
Don't ask me how know, but beware of it on cast iron especially exhaust manifolds.

We were going to weld up a somewhat dodge fire engine cracked manifold when we had a rush of excrement to the brain idea to soak in a molasses mix.

The consensus was about 9:1 water to molasses mix.We forgot about it and it was left submerged some 3 weeks.

When removed the mix had eaten the carbon out of the cast iron leaving it looking like a sponge.

The remaining metal ,however was very clean.

Grahame
kwijibo99
26th Dec 2016, 11:24 PM
Molasis definately works faster when the solution is warmer so summer time is better in our southerly latitudes.
BobL
27th Dec 2016, 09:58 AM
If you had a lot of stuff to do agitation should also speed things up.
Something like a small (non-magnetic) pump, say from a washing machine would be the go,
19brendan81
29th Dec 2016, 09:47 PM
I did a heap of parts for my FJ in molasses a year ago. Did it in summer and it was fast (2 weeks) but bloody messy and stinky. Even after cleaning in hot soapy water the parts reeked for months. I wouldn't do it again. I would just knuckle down with a wire wheel on bigger beats and use electrolysis for the smaller stuff.
Goggomobile
1st Jan 2017, 07:45 PM
I got A 20 l tube 12 m ago and did some tests ... works well on the right steel but if it has impurities it can go honey comb like Grahame mentioned ... always best to do a test first .. if you can ...

I put a sealed lid on at first to shelter from the rail ... end up popping the lid.. put some plastic with a rope which worked since it let the gasses out...

Make sur you check it every few days just to make sure there is no crap steel in the mix...

If ok gets into all of those nooks and crannies ...

Randal