Large sheet butt weld on Aluminum

[fishbum]

First just learning to mig aluminum with Miller 211 and spool gun
been playing a lot with settings and
stuff. I have a goal of building a boat! 1/8" sheet
will have all kinds of welds on it but the first may half to be a but weld on the bottom! About 56" long. The pieces are 8' long
first how do you do it without it warping all over the place. And then
in testing but welds I get lots of bead on the back of the
plate I expect to have to weld both sides of it so am I welding to hot
in the first place? Jumping back
and forth with short arc and spray
transfer at least what I consider it is.
Along with this I get tons of burn through showing on the back of test plate
what is the secret to not burning through so
much. Thanks

[cruizer]

1/8 plate you should really be using a pulse machine, with that unit your going to have to make alot of spot and short 1" welds with no more than 030 4043 wire, Argon at 15CFH, gun pushing at an angle to the work, NOT straight on, and ALL spray arc

[eecervantes83]

I weld aluminum all the time with this machine here are my settings. Wire speed is at 90-91 & temp set at 6. I also recommend swapping tips to the ones used on your mig gun . With 030 wire 4043

[Tryagn5]

First just learning to mig aluminum with Miller 211 and spool gun
been playing a lot with settings and
stuff. I have a goal of building a boat! 1/8" sheet
will have all kinds of welds on it but the first may half to be a but weld on the bottom! About 56" long. The pieces are 8' long
first how do you do it without it warping all over the place. And then
in testing but welds I get lots of bead on the back of the
plate I expect to have to weld both sides of it so am I welding to hot
in the first place? Jumping back
and forth with short arc and spray
transfer at least what I consider it is.
Along with this I get tons of burn through showing on the back of test plate
what is the secret to not burning through so
much. Thanks

Seems to me you bettar buy about 30 cans of flex seal because that boat is going to leak! Every time you stop and start is a very cold weld on aluminum, this is very bad on a boat. Also the stringers of the boat should be installed before seam welding the bottom. Making an aluminum boat from scratch is not an easy task, a pulse welder makes it much easier.
kevin

[walker]

Post up a pic of your design. Try to design, and build with as few pieces as possible, fewer seams. Grind your stops before you restart. If possible a different joint design rather than a butt weld. Try to incorporate structural stringers into the design as well, as this makes a good place to weld to without long butt welds. Look at commercial designs to see how theirs are made.

[fishbum]

Boat

Wow, guess I will opt for one piece bottom! Or just buy another hull.
I have bought several from a small custom builder and I know they use pulse mig
but can't see anyone doing 18' without stopping? Eecrvantes83. That seem real hot on your 211 settings. I'm still learning but right now I'm around 4.5 and 6 on wire. I guess I should ck forum for this but how the heck do you cut back the Cratering at end of weld! Thanks

[ja baudin]

Building a boat with a 211 is limited in my opinion. Its a small hobbyist machine that lends itself more to small aluminum projects, however it can be done. I would compare it to framing up a house with a tack hammer compared to using a framing nailer or nail gun. Both get the job done, but you limit yourself with the underpowered option. You may not be satisfied with the end result, which may result in time and material wasted.

However, good luck with your project and remember, you may be trusting your project with your life and the life of others who use it. Open up a seem in rough open water and your in trouble.

If I would build a boat, I would purchase a pre-crimped hull and just finish the inside. Outcome would be safer and nicer and would still be a great project to enjoy building.

Ja

[eecervantes83]

The crater at the end of the weld is covered with at tack right after the weld bead is done . I mean in a split second.

[eecervantes83]

This machine is no hobby welder under the right hands this machine can handle large difficult jobs easy. I'd post up pictures of some jobs and welds but my mobile app is giving me problems posting.

[fishbum]

Mig crater

The crater at the end of the weld is covered with at tack right after the weld bead is done . I mean in a split second.

Thanks I will try that. Any video out there that showed that? Again the numbers
you stated on your 211. 6 and 9 on wire are you on 120? Also what difference will I see again with 1/8 switching from
.30 wire to .35. ? A guy I know built a boat for the first time and a miller rep had him change from .30 to .35. Had less trouble overall !

[eecervantes83]

I dont think I ran 035 wire before. My supplier had 030 & that's what I stuck with. I only weld aluminum on 220.

[ja baudin]

This machine is no hobby welder under the right hands this machine can handle large difficult jobs easy. I'd post up pictures of some jobs and welds but my mobile app is giving me problems posting.

I know that its my opinion, but lets face it, you will not find this machine in an aluminum boat fabricating shop. In my mind, that means hobbyist as opposed to manufacturer/fabricator based upon its limitations.

[eecervantes83]

He ain't building for a profit and he ain't building for production. It might take him a bit longer and use a different (technique?). But its doable and its been done before. Plus it will give the operator time to master the spoolgun.

[Danl]

Might give this thread a little bump... I wonder what the status is of this boat build...?

[kiwi]

Here is some good information on aluminum boat building.

http://weldingweb.com/showthread.php?409811-I-m-building-an-aluminum-skiff&highlight=Aluminum+boat+build

http://weldingweb.com/showthread.php?287151-aluminum-boat-build&highlight=Aluminum+boat+build