Spoke to him last night, he's still in the business but as soon as I mentioned powder coated boat he said no f***ing way, his advice was the only way you will get it completely back to bare ally is by garnet blasting in a booth, the only stripper I know of that will remove powder coat is Benco B-17, the stuff can be pretty dangerous and brushing or spraying it on isn't recommended, proper procedure is to bath it and even though it's safe to use on aluminium it will eventually have some effect after a few hours.
Way out of my depth here but would a wrap be an option? Do your patches, rough sand, prime, cure and wrap.
Well first crack at some of the holes in the boat are very interesting. Welding clean/new sheet and trying to weld holes that have had years of salt exposure is like I’m trying to weld stainless or something.
Democracy: Simply a system that allows the 51% to steal from the other 49%.
Cleanliness is the clue, TIG is really pretty easy (and I am no welder) but I have done lots and had good success, make sure everything is clean, gas flow good, machine is set right (and is a HF TIG, also if doing it outside, wind can be an issue.
Ok so it took me most of the weekend to work out what was going wrong. I was expecting to be doing some cleaning before working up a puddle but this was ridiculous. When I was doing my practice welds I was close to the power point with the machine hooked into the 15amp outlet.
When I moved everything over to the boat I hooked up my 30m 15A Caravan lead. What I couldn’t tell was that when I strike an arc, the Amps drop to about 55% of what I have set. At 100amps, which should be more than enough, the Amps were dropping to only 55. Cranking it up to 200 I got 115amps and the ally started puddling quite quickly. Problem solved I hope.
Democracy: Simply a system that allows the 51% to steal from the other 49%.
As an experienced blaster painter I have to agree with you Lovey. Very slow and tedious to completely remove powdercoating and also will create distortion to the aluminium due to the heat it creates.
You can do a quick whip blast to take the shine off the powdercoat using a fine abrasive, large nozzle and lower the pressure.
I still can't get my head around powder coating boats, what were they thinking?
Lovey do u have your base current at 200amps? Are u using a foot peddle? Some machines have variable amps on the foot peddle others are by the machine
If your only welding holes are u using down slope at all? I would turn it off or turn the dial so its not effective
Depending what machine u have you really shouldnt run welders on extension leads, i do only because i have to
200ams reduced to 115amps sounds like your welder settings are off maybe your running the innitial arc at 200amps and base current 115amps
If 115amps works fine for whatever your welding u should really set the welder up to 140-150amps and use the foot peddle that'll break through the hard layer than u easy off on the peddle untill u can run the molten pool
Remember if u freshly wire brush the aluminium right before welding your removing that hard oxide layer the higher amps are needed to break through
Me personally i wouldnt touch powder coating with a grinder, sander or anything that will eat it and place gases in the air
When i worked at powder coating in 1998 the boss use to burn the converyer hooks in a 200L drum outside he use to get me to sort the hooks out once burnt f... shitty job
I tried my hand at powder coating while i was there i kept putting to much on than not enough and the bloke on the other side of the booth kept winging i was blowing to much powder his way
I have no idea Lovey but have u noticed if u have council clean ups where u place all your rubbish on the sidewalk and the council collects it that everytime i see the metal scrappers leave behind steel like fan parts the main stalk and cages because they are powder coated the scrappers tend to leave behind anything powder coated for some reason