Originally Posted by Mike D

Ugh, that looks nasty! Good thing you caught it when you did.

Media blasting is a mixed bag.

Sand is the fastest, most efficient but it has its problems. It strips EVERYTHING from the area you are working. Paint, rust, thin sheet metal, weather stripping, sealant, rust preventative coating, you name it. An over exuberant application can also weaken the surrounding metal. It is a pain in the arse to clean all the media from the areas where it WILL infiltrate. The use of a good respirator system/device, goggles, gloves and head covering is a must! You definitely do not want to do this in an enclosed area such as a home work shop. You'll be cleaning the detritus from this for months and that includes orifices/wrinkles on your body you didn't realize you had.

Glass beading is the next most efficient method. Not as aggressive and not as harmful to existing metals/painted areas, etc. as the sand. Tends to leave a "mottled" surface. Same precautions need to be taken regarding protection. Clean up is a LITTLE easier, but not much.

Walnut shells are next. I'm not impressed with their rust removal properties but they do work. Much slower and not as efficient as the previous methods but it does have the advantage of the media being organic and if you happen to leave a mess in the yard, with the exception of the removed rust, paint, etc. , it will all wash away the next time it rains. Same safety precautions. Clean up is easier. Shop vac, compressed air nozzle and a little brush work will get 99% of the media from the work area. Easier to shower off also.

Soda blasting is last on my list. Most expensive and least effective cleaning heavily rusted areas. Does a great job removing paint without damaging the surrounding materials but that in itself speaks for its rust removal ability. It'll knock off the loose, flaky stuff but it doesn't do a good job on the deeper corrosion. Easiest to clean. Just hose it down and all the media dissolves. Give it a good blast of compressed air to get the water out of hidden areas and you're done.

Me? I wire brush to determine the extent of the corrosion and bead blast the rust. What I find after the beading determines my next step.