Here's some follow up on my ball of rusted chain...

I talked to two more companies who discouraged me from doing the EDTA treatment, Derick.  They both said it might work if I could completely cover the chain and let it stand for a day or two...or more.  The cost of that seemed prohibitive.

I went back to the boat this weekend and used a pneumatic powered needle gun which got the rust off the top layer of chain, but didn't do much for underlying layers.  Fortunately the boat is immediately adjacent to the yard's big air compressor, which they let me use. I doubt that the electric rotary hammers with hammer function only (no rotary action) would be powerful enough or last long enough to do this job.   I then switched to a pneumatic chisel ($20 at Home Depot!), which concentrated the power much more efficiently.  The pointed chisel only found it's way between links and got stuck frequently, but the 5/8" wide flat chisel seemed just about right.  Two of us alternated between squeezing an arm and head into the chain locker or working on the deck where we kept tension on the chain with an extra halyard and the chain snubber hook.  I stuck the hose from my shop vac into the hawsepipe alogside the chain to get some air circulating through the locker...that worked well in getting the fumes down to a minimum.  A few times we had to bring another line down the hawsepipe  and put it through a link on a loop of chain that had fallen over the part going out through the pipe and further trapped it at the bottom of the ball.  We were then able to get tension on that part of the chain which made it possible to loosen it with the chisel.  After 9 hours we were able to extract about 40 ft of the stuck chain out through the hawsepipe.  That included two trips to Home Depot for different chisels and a broken spring.  Much of what is left now is in smaller balls of rusty chain that will have to be broken up to get them out through the pipe, but it should be easier than what we did this weekend. 

We are both pretty bruised up from laying across the two cabinet openings that access the locker, in spite of 4 layers of a firm rubber matting between our ribs and the wood.  I will fashion some kind of wooden plank to lay on next time.  You will need ear protection while using the pneumatic chisel.

I've already vacuumed about 25 lbs of rust chips from the locker and there will be at least another 25 lbs to clean out when we're finished. 

I'm not sure how much good the PB Blaster did, but I sprayed another can on the chain before I left in hopes it will loosen it some more before I go back to get the last 50 ft or so out.

If there's anything different to tell by the time I get it all out, I'll let you know.

Kent (call me "Rusty")

SM243 Kristy Tiger Point Boat Yard Fernandina Beach FL