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#1
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I am seriously interested in learning to weld aluminum. In the interest of
future projects I fugured I would buy some scrap aluminum froma local metal worker to practice on. So...which alloys should I get. These are for freshwater projects, but a small bay boat or small skiff for bay fishing may be in the works for the future so sal****er applications are not totally out of the question. -- Bob La Londe Fishing Arizona & The Colorado River Fishing Forums & Contests http://www.YumaBassMan.com -- Posted via a free Usenet account from http://www.teranews.com |
#2
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posted to rec.boats.building
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Bob,
First - Do you know how to weld (any type)right now? If you do not, go find a community college or local technical school and get some instruction. They may ever have an advanced class that will get you closer. Second - You should reseach which alloys you will work. There are a number of choices and some limit the effective welding process that can be used. I have not worked in this field in years, so I do not choose to suggest without knowing the actual application and doing some study on my own. Third - There are are multiple processes for welding aluminum available. All are different and some are very different. Some alloys are best welded with TIG (expensive) others can be handled with SMA (looks like welding rod and the easiest is MIG (has a gun that lays weld). Most of your practice should be laying beads on flat stock so don't buy new metal. After you learn to weld and pick up some good used gear, go find a scrap metal dealer that get flat stock from some where and make a deal to buy some from him with the understanding that you can sell it back to him as larger pieces for not much less than you bought it for. Build yourseld some forms and holders to let you weld uphill down hand and overhead and try to assemble soem structures that are really difficult and hard to manage and you may be close to boat building. Keep up posted. Best of luck, Matt Colie (welded in big steel ships for a while and little stuff for ever) Bob La Londe wrote: I am seriously interested in learning to weld aluminum. In the interest of future projects I fugured I would buy some scrap aluminum froma local metal worker to practice on. So...which alloys should I get. These are for freshwater projects, but a small bay boat or small skiff for bay fishing may be in the works for the future so sal****er applications are not totally out of the question. |
#3
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posted to rec.boats.building
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![]() "Matt Colie" wrote in message ... Bob, First - Do you know how to weld (any type)right now? If you do not, go find a community college or local technical school and get some instruction. They may ever have an advanced class that will get you closer. I do a fair job with my little MIG welder on any kind of steel. I've got a gas bottle and flow regulator for stainless. That takes a little more work to get jsut right. I do heavy steel stock with my cracker box AC welder, but the best welder I ever used for heavy stock was a Hobart DC stick welder. Wow talk about smooth. Second - You should reseach which alloys you will work. There are a number of choices and some limit the effective welding process that can be used. I have not worked in this field in years, so I do not choose to suggest without knowing the actual application and doing some study on my own. I have been doing a little research on my own, but I was hoping to get a nice definitive answer from some one who builds boats that would say, "This alloy works very well in a wet environemtn." Third - There are are multiple processes for welding aluminum available. All are different and some are very different. Some alloys are best welded with TIG (expensive) others can be handled with SMA (looks like welding rod and the easiest is MIG (has a gun that lays weld). Yep, I read about TIG & MIG already. Like I said I've got a MIG welder and a flow regulator already. Figured I would get a U-groove push wheel for my wire, and pick up a straight (not mixed) bottle for doing aluminum, and then I'ld wander over to Mike's Metal works and buy some aluminum off his scrap rack to practce with. Most of your practice should be laying beads on flat stock so don't buy new metal. After you learn to weld and pick up some good used gear, go find a scrap metal dealer that get flat stock from some where and make a deal to buy some from him with the understanding that you can sell it back to him as larger pieces for not much less than you bought it for. I figured to get a bunch of scrap to practice on froma local metal shop. Build yourseld some forms and holders to let you weld uphill down hand and overhead and try to assemble soem structures that are really difficult and hard to manage and you may be close to boat building. Part of practice. Keep up posted. Best of luck, Matt Colie (welded in big steel ships for a while and little stuff for ever) -- Bob La Londe Fishing Arizona & The Colorado River Fishing Forums & Contests http://www.YumaBassMan.com Bob La Londe wrote: I am seriously interested in learning to weld aluminum. In the interest of future projects I fugured I would buy some scrap aluminum froma local metal worker to practice on. So...which alloys should I get. These are for freshwater projects, but a small bay boat or small skiff for bay fishing may be in the works for the future so sal****er applications are not totally out of the question. -- Posted via a free Usenet account from http://www.teranews.com |
#4
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I do a fair job with my little MIG welder on any kind of steel. I've got a
gas bottle and flow regulator for stainless. That takes a little more work to get jsut right. I do heavy steel stock with my cracker box AC welder, but the best welder I ever used for heavy stock was a Hobart DC stick welder. Wow talk about smooth. Hi there, Ive been a full time welder for about 5 years now, and a tinkerer most of my life before that. I spent a year doing contract work stick welding trawlers but in the last year and a half most of my work has been aluminum; big tip trailers, and aluminum plate boats. Here's my 2 cents worth... I dont think it really makes too much of a difference what alloy you go with, particularly for fresh water. Just go with something that isnt too hard. We use 5083 marine alloy, but a lot of the 5000 series alloys are suitable. You'd do well to decide early on if you want to go for a 'plate' boat or a 'pressed' boat. Plate boats use relatively thick sections (1/4" or more) of aluminum and hold their shape well. The boats my company makes are of this variety, take a look at the web page if you like (note, this is not a plug) www.barcrusher.com.au Typical dinghys and runabouts use much thinner sections, sometimes 1/8" or smaller. The smaller sections wont keep shape without being formed a bit, and the most common way of doing it is by pressing the sheets to give them a sort of a clinker look. You can get the same sort of effect by buying a rolling wheel, marking the lines on the sheet then rolling them on the wheel. The heavier boats are much more solid and easier to weld, but you're probably looking at around $6,000 to build a 20" with a cuddy cabin - not including fitting it out or an engine. Aluminum prices are going up and up. If you're going with plate, you're pretty ok, you should get away with yusing your small mig. You'll need a plastic liner for your gun, and different tips. If you're using flux core, you'll need to swap to a non-grooved roller set. If you're going to go with pressed, you'll probably need a lot of skill, or a better welder - preferrably both. The welders we use at work are about $20,000 Fronius units with all the options (push pull gun, water cooled leads) that do a synergic pulse mig, and have adjustable current *on the gun* in the form of a dial or buttons in one amp steps. This gives extremely fine control over heat and its adjustable while you're welding, so you can turn it up as you get to a corner, or down if you start to burn through. They also have 4 step options (hot start, run, crater fill) to get a tig-like experience in a fraction of the time. The synergic pulse is truly excellent for overhead and vertical up welding and gives a minimum of spatter. In truth, like me, you will probably never be able to justify buying a unit like this, but thats what it takes to compete at that sort of a level when it comes to aluminum. All the players have them. If you're going to go ahead with your (im guessing single phase, off brand) welder, start by getting some reasonable size sheets 1/4" or so. If there's a boat maker in your area hit them up for scrap. You'll probably get a box full for a six pack. Aluminum is great in some ways - unlike steel you'll never get a pretty looking weld that doesnt do anything. For this reason alone, i think the standard of aluminum welding is generally higher than steel. It has to be spotlessly clean, or you're wasting your time. use a stainless wire wheel, or a flap disk. Temperature and root gap are critical. Filling gaps is not easy. Unlike steel, it doesnt give any signs the weld pool is too hot, so you'll be quite surprised to see the puddle drop right through the plate every time it happens. Dont sweat it too much; it still happens to me ;-) you may find that setting the welder is hard, partly because it doesnt make that good sound you get with steel, and partly because you may only have 5 voltage settings on your unit. Hotter is better, so start by just 'tack' welding until you get the hang of it. You'll see that just before it drops out, the pool goes from greyish to a bit shiny, then it sinks a little, then very quickly disappears. Once you can control the puddle to the point you can 'sink' it level with the plate and not drop it out, you're doing well. butt welds are tricky, so progress to a fillet. a 'step' in your gun movement of around 1/4" will give a pretty looking weld. The most critical things are probably cleanliness of material, correct heat, consistent gun angle and consistent stick out, in that order. If you get a lot of grey/black discoloration around your bead it means you're not getting enough gas coverage - move your gun closer. If i were in your position, Id see if there is a local boat builder who would take me on part time on weekends if i worked for free. In return you'll learn how to do a professional looking weld, probably pressure testing, have access to heaps of scrap, and they'll usually let you use the equipment after hours. good luck ;-) |
#5
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posted to rec.boats.building
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![]() "imagineero" wrote in message ps.com... I do a fair job with my little MIG welder on any kind of steel. I've got a gas bottle and flow regulator for stainless. That takes a little more work to get jsut right. I do heavy steel stock with my cracker box AC welder, but the best welder I ever used for heavy stock was a Hobart DC stick welder. Wow talk about smooth. Hi there, Ive been a full time welder for about 5 years now, and a tinkerer most of my life before that. I spent a year doing contract work stick welding trawlers but in the last year and a half most of my work has been aluminum; big tip trailers, and aluminum plate boats. Here's my 2 cents worth... I dont think it really makes too much of a difference what alloy you go with, particularly for fresh water. Just go with something that isnt too hard. We use 5083 marine alloy, but a lot of the 5000 series alloys are suitable. You'd do well to decide early on if you want to go for a 'plate' boat or a 'pressed' boat. There was a lot of great stuff in your post. Thanks. I was thinking more along the lines of pressed, although actual structural bending or forming was not part of my plan for the main hull design. Wrapping and flexing would be more accurate. Plate would be way to heavy for some of the smaller designs I have in mind. I was thinking to basically light bend most of the sheets using .125 for most things and creating structural ribs out of top hat bent sheet. I figured to use some 1/4" plate for a slightly different design than most modern production boats for increased ridgidity for stringers and knee bracing as well as rear corner gunnel to transom bracing so that the boat will actually standup to the horsepower that the CG formula says is appropriate for the design. Most production boats flex to much and begin to get stress fractures when run with their max rated HP even after only a couple years. Your comments on welding the thinner sheet have made me step back and reconsider. I had hoped to avoid stitch and glue even though it is much easier, because of the extreme heat and dry conditions where I live. I have read all about encapsulation etc, and I have also seen real boats. Wood just does not hold up in the desert no matter what you do to it. Now your comments about the difficulties of welding sheet aluminum make me reconsider that approach as well. I suppose the thing to do is get some sheet and a gas bottle and see what I can do. You are right in that I have a cheap MIG (with only 2 heat settings). Usually I use flux core except for stainless because its just faster to do a small repair weld. My business can justify the expense of a better MIG welder, although an autodarkeneing shield is probably going to come first. I know the duty cycle of the one I have is abysmal. This one mostly gets used for minor fabrication for my business. I probably can't justify top of the line. Anything over a couple thousand would be pretty hard to justify. Anyway, thanks for your suggestions regarding a local boat builder. Its a great idea, except as far as I know there aren't any. The nearest would be about 180 miles in either direction. I probably need a better MIG anyway, so I guess I'll go hunt up another gas bottle and pick up some scraps from Mike and see what I can do. -- Bob La Londe Fishing Arizona & The Colorado River Fishing Forums & Contests http://www.YumaBassMan.com -- Posted via a free Usenet account from http://www.teranews.com |
#6
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posted to rec.boats.building
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I can't offer much in the way of advice on welding - I am now building a 20'
W Atkin design in aluminum; cutting and fitting the pieces myself, and hiring a local pro to do the welding. Pictures and discussion on the Yahoo AtkinBoats site http://groups.yahoo.com/group/AtkinBoats/ (registration required). 1/8" can be welded, but it isn't easy. But for smaller boats, it is still pretty heavy - about the same as 3/4" plywood. Use 5000 series (5083 or 5086 for salt water) and 6061 for angles, pipe, and extrusions (6063 if you can find it). Build yourself a little skiff or dinghy for practice. It will come in handy, and last forever with zero maintenance. Around here standard sheets seem to be 6'x20', and you could build a nice narrow little skiff from one sheet. There are all kinds of nice plywood designs out there that can be adapted to metal. And pick up Pollard's book, and Gerr's "Boat Strength". Sal's Dad "Bob La Londe" wrote in message .. . "imagineero" wrote in message ps.com... I do a fair job with my little MIG welder on any kind of steel. I've got a gas bottle and flow regulator for stainless. That takes a little more work to get jsut right. I do heavy steel stock with my cracker box AC welder, but the best welder I ever used for heavy stock was a Hobart DC stick welder. Wow talk about smooth. Hi there, Ive been a full time welder for about 5 years now, and a tinkerer most of my life before that. I spent a year doing contract work stick welding trawlers but in the last year and a half most of my work has been aluminum; big tip trailers, and aluminum plate boats. Here's my 2 cents worth... I dont think it really makes too much of a difference what alloy you go with, particularly for fresh water. Just go with something that isnt too hard. We use 5083 marine alloy, but a lot of the 5000 series alloys are suitable. You'd do well to decide early on if you want to go for a 'plate' boat or a 'pressed' boat. There was a lot of great stuff in your post. Thanks. I was thinking more along the lines of pressed, although actual structural bending or forming was not part of my plan for the main hull design. Wrapping and flexing would be more accurate. Plate would be way to heavy for some of the smaller designs I have in mind. I was thinking to basically light bend most of the sheets using .125 for most things and creating structural ribs out of top hat bent sheet. I figured to use some 1/4" plate for a slightly different design than most modern production boats for increased ridgidity for stringers and knee bracing as well as rear corner gunnel to transom bracing so that the boat will actually standup to the horsepower that the CG formula says is appropriate for the design. Most production boats flex to much and begin to get stress fractures when run with their max rated HP even after only a couple years. Your comments on welding the thinner sheet have made me step back and reconsider. I had hoped to avoid stitch and glue even though it is much easier, because of the extreme heat and dry conditions where I live. I have read all about encapsulation etc, and I have also seen real boats. Wood just does not hold up in the desert no matter what you do to it. Now your comments about the difficulties of welding sheet aluminum make me reconsider that approach as well. I suppose the thing to do is get some sheet and a gas bottle and see what I can do. You are right in that I have a cheap MIG (with only 2 heat settings). Usually I use flux core except for stainless because its just faster to do a small repair weld. My business can justify the expense of a better MIG welder, although an autodarkeneing shield is probably going to come first. I know the duty cycle of the one I have is abysmal. This one mostly gets used for minor fabrication for my business. I probably can't justify top of the line. Anything over a couple thousand would be pretty hard to justify. Anyway, thanks for your suggestions regarding a local boat builder. Its a great idea, except as far as I know there aren't any. The nearest would be about 180 miles in either direction. I probably need a better MIG anyway, so I guess I'll go hunt up another gas bottle and pick up some scraps from Mike and see what I can do. -- Bob La Londe Fishing Arizona & The Colorado River Fishing Forums & Contests http://www.YumaBassMan.com -- Posted via a free Usenet account from http://www.teranews.com |
#7
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posted to rec.boats.building
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Sal's Dad wrote:
I can't offer much in the way of advice on welding - I am now building a 20' W Atkin design in aluminum; cutting and fitting the pieces myself, and hiring a local pro to do the welding. Pictures and discussion on the Yahoo AtkinBoats site http://groups.yahoo.com/group/AtkinBoats/ (registration required). 1/8" can be welded, but it isn't easy. But it's not that hard, if you take a bit of care. 1/8" aluminum sheet is not really harder than 1/8 steel to weld. Angles and bar stock are just as easy to weld as steel. It's a different metal, and you must get used to the characteristics of it, but it's really no harder, just different. But for smaller boats, it is still pretty heavy - about the same as 3/4" plywood. Use 5000 series (5083 or 5086 for salt water) and 6061 for angles, pipe, and extrusions (6063 if you can find it). Build yourself a little skiff or dinghy for practice. It will come in handy, and last forever with zero maintenance. Around here standard sheets seem to be 6'x20', and you could build a nice narrow little skiff from one sheet. There are all kinds of nice plywood designs out there that can be adapted to metal. And pick up Pollard's book, and Gerr's "Boat Strength". Sal's Dad "Bob La Londe" wrote in message .. . "imagineero" wrote in message oups.com... -- “TAANSTAFL” __________________________________________________ __________________________ "A prudent man foresees the difficulties ahead and prepares for them; The simpleton goes blindly on and suffers the consequences." - Proverbs 22:3 __________________________________________________ __________________________ |
#8
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You are right in that I have a cheap MIG (with only 2 heat settings).
Usually I use flux core except for stainless because its just faster to do a small repair weld. My business can justify the expense of a better MIG welder, although an autodarkeneing shield is probably going to come first. I know the duty cycle of the one I have is abysmal. This one mostly gets used for minor fabrication for my business. I probably can't justify top of the line. Anything over a couple thousand would be pretty hard to justify. The good news is that pricing on power tools is falling further every day. Most of the stuff from china is not yet up to spec, but will be in a few years. CEA makes some pretty good welders that offer excellent value for money in my opinion. We have a whole range of welders at work, right up to 800A Lincolns, but we just got in a couple of CEA's new three phase units, i think they're rated to about 400 or maybe a bit more off the top of my head. They only cost AU$1200 including sales tax which is about a third of the price of a comparable lincoln over here. I know they have some fairly good single phase units available in aus for AU$800, so i imagine US$500 would buy you a lot of welder right now. Three phase is great if you have it, if not, you can still do fine with single phase. Look for as much adjustment in the voltage as possible, at least a coarse and fine knob. Dont get too concerned about things like burn back and ramp up etc. Most welders have adjustments for these on the PCB anyway. Try to get one with a universal gun fitting rather than a built in gun. You can change them to the universal one later if you have to but its ugly to do so. If you're stuck with the built in gun you'll probably find that its not up to the task and doesnt have the range of consumables you'd like. If you can afford to spend a bit more, you can get some wonderful do-it-all inverter boxes nowadays for under $2000. These are an all in one pulse mig/stick/arc/gouging unit with more adjustments than you can poke a stick at. Most are fully digital. Have a play with all the functions that are important to you (especially TIG if you are going to use it) before shelling out your hard earned - each unit has its own quirks that you'll either love or hate. In terms of helmets, the good stuff is still pricey. I've used most of the speedglass units including the top of the range big screen models with all the adjustments, sidewindows and the ventillation system. Work provides them to us for work where we get exposed to fumes. I have a lincoln dominator which i love, it was about half the price of the top of the line speedglass (cost me about AU$450) but i find it much more comfortable to use. it has most of the same features (9-13 shade adjustability, sensitivity, delay) lincoln claims that their helmet has a faster reaction time which is more suitable for tig, there may or may not be truth in this. I do mostly mig and a little tig with mine, but i find that when i wear the speedglass i tend to suffer more from eye strain. most welders prefer the headgear on the speedglass, its lighter and a bit more comfortable. One thing i find nice about the lincoln is that in its 'off' state its slightly darker (i think one shade) than the speedglass. While this may sound silly, it makes it the right shade for oxy welding/cutting. I really hate oxy glasses, so this is a nice feature for me. Its definitely worth having a go with welding the aluminum with your current welder. You'll learn a lot, and there are some great newsgroups that are welding/metalworking focussed. The guys on these lists have consecutive lifetimes of experience in the industry and you really learn a lot by talking to them. Good luck with it all~ Shaun |
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