Announcement

Collapse
No announcement yet.

Mig welding Aluminum plate to cast Al

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • FusionKing
    replied
    Originally posted by DougM View Post
    Ok guys.
    This weekend was a bust for welding. The goats are due for kidding, and I had to build some shelters quickly.
    Ordered 4943 and 5356 fillers in 0.035" and they're on the way. Plenty of tips and the new roller drive are here, as is the SS wire wheel. Got some 6061-T6 0.25" bar stock to mess with.
    Questions:
    Reading some of Ed Craig's Al welding propaganda...
    He hints that a higher amperage at start can be a good thing on thicker aluminum ( > 6mm) and that includes 0.25" stuff. He also hints at higher run-in speed (higher amperage). Unknowingly, I set my spool gun run-in at 50% of welding wire speed. Haven't tried that yet, but it may be best to use something like 110% or higher (up to 150% on my MM 251) for the initial zap. Perhaps will help with less burn-back and gratuitous tip-welding as well.

    Another tip Edward got me thinking about is the possibility of adding a start tab and an end tab (extra pieces of Al material preceding and following a weld) so to reduce cracking and cratering, and promote weld penetration at the beginning of the permanent weld. The tabs would be cut off afterwards.

    He also indicated that .045 wire is best for 0.25" base material ( >6mm), as I've seen in most other references.

    http://www.weldreality.com/aluminum-welding-2.htm

    ALSO.... I found a handy-dandy Hobart/Maxal filler chart (finally) that I hadn't found in all my other multitudes of searches.

    http://www.hobartbrothers.com/downlo...ler__eNttQ.pdf

    Here, the chart indicates that for 5052 to 5052 welds, especially for fillets, 5556 or 5183 are the most recommended, and 5356 is ok, too. 4943 is given a poor grade for sheer strength. 5556 and 5183 are hard to find, so the 5356 will be fine. I'm kinda concerned about the sheer strength between the 5052 ring (0.25" thick,6" wide, 42" circumference, -13" OD) and the two 5052 side plates (0.25" thick, +13" ID, 22"OD), and since fillets are more apt to fail than the base, 5356 may be the better choice here.

    HOWEVER, for welding cast Al to 5052, 4943 filler is highly suggested.

    Hope I'm not overthinking this. Just want the first attempt (after practice) to be the last attempt with good results.
    Suggestions, criticism, anything?
    Thanks!
    -doug

    -One of our does had two healthy newborn kids just an hour ago!


    Yes (you are overthinking now)
    Instead, keep reading and learning and retain all these good facts. Get your stuff all working and then play with it all.
    I have read all Ed says and that is all pretty good for thought.
    This isn't the space shuttle and you're not an aerospace welder. Keep it simple
    But stick to your plan!!! Weld scrap and get good. Then prep parts and use 4943.

    Welding is a lot like gunslinging.......about the time you think you're good, some Hick [email protected] steps out of a dark alley and makes you look like a beginner.

    Leave a comment:


  • DougM
    replied
    Ok guys.
    This weekend was a bust for welding. The goats are due for kidding, and I had to build some shelters quickly.
    Ordered 4943 and 5356 fillers in 0.035" and they're on the way. Plenty of tips and the new roller drive are here, as is the SS wire wheel. Got some 6061-T6 0.25" bar stock to mess with.
    Questions:
    Reading some of Ed Craig's Al welding propaganda...
    He hints that a higher amperage at start can be a good thing on thicker aluminum ( > 6mm) and that includes 0.25" stuff. He also hints at higher run-in speed (higher amperage). Unknowingly, I set my spool gun run-in at 50% of welding wire speed. Haven't tried that yet, but it may be best to use something like 110% or higher (up to 150% on my MM 251) for the initial zap. Perhaps will help with less burn-back and gratuitous tip-welding as well.

    Another tip Edward got me thinking about is the possibility of adding a start tab and an end tab (extra pieces of Al material preceding and following a weld) so to reduce cracking and cratering, and promote weld penetration at the beginning of the permanent weld. The tabs would be cut off afterwards.

    He also indicated that .045 wire is best for 0.25" base material ( >6mm), as I've seen in most other references.

    http://www.weldreality.com/aluminum-welding-2.htm

    ALSO.... I found a handy-dandy Hobart/Maxal filler chart (finally) that I hadn't found in all my other multitudes of searches.

    http://www.hobartbrothers.com/downlo...ler__eNttQ.pdf

    Here, the chart indicates that for 5052 to 5052 welds, especially for fillets, 5556 or 5183 are the most recommended, and 5356 is ok, too. 4943 is given a poor grade for sheer strength. 5556 and 5183 are hard to find, so the 5356 will be fine. I'm kinda concerned about the sheer strength between the 5052 ring (0.25" thick,6" wide, 42" circumference, -13" OD) and the two 5052 side plates (0.25" thick, +13" ID, 22"OD), and since fillets are more apt to fail than the base, 5356 may be the better choice here.

    HOWEVER, for welding cast Al to 5052, 4943 filler is highly suggested.

    Hope I'm not overthinking this. Just want the first attempt (after practice) to be the last attempt with good results.
    Suggestions, criticism, anything?
    Thanks!
    -doug

    -One of our does had two healthy newborn kids just an hour ago!
    Last edited by DougM; 02-27-2018, 06:18 AM.

    Leave a comment:


  • shovelon
    replied
    4943 and 4043 weld very much alike Doug due to the high sillycon content. Interesting history of 4043 and 4047 is that they both started off as brazing fillers. The flow characteristics were paramount. Although I am phasing out 4043 in favor of 4943 I still use 4047 to patch porosity on dressed joints before polish.

    Leave a comment:


  • DougM
    replied
    Thank you Shovelon for expounding on the details. I was thinking of using 5356 filler on the 0.25" 5052 plate (rolled ring and side plates) and 4943 on the ring and cast wheel, but looks like I can use 4943 for all the welds. (I think)

    I haven't assembled all the materials yet, but will be messing with assorted cast scrap today with 4043 since that's what I have at this moment. 4943 is on it's way along with 5052 plate.
    I'll keep you posted on my progress and results.

    Reel fun.

    Leave a comment:


  • shovelon
    replied
    When choosing a filler for spoolgun work you really must consider how much base metal dilution you can mix with the filler. Since there is little with mig alum 4043 would be a disastrous choice as it is highly dependent on the alloys in the cast for strength buildup. Not so with 5356 but way too much porosity will result from spoolgun welding on alum cast. Therefore the best compromise is 4943, which is not dependent on base metal dilution for strength, and the generous amount of silicon holds down the porosity. 4943 was developed with this conundrum in mind. I have been phasing out 4043 altogether since 4943 came out. It really is a wonder filler.

    Leave a comment:


  • ryanjones2150
    replied
    Every cast aluminum wheel I've welded on, granted I tig welded them, I have never had a problem. At least nothing like the problems one can imagine with typical cast aluminum. Maybe cast aluminum wheels are just made with a better material. I have no idea, that's just a guess. I've also never welding on a scooter wheel.

    Leave a comment:


  • FusionKing
    replied
    You're welcome!!
    Now keep us posted on the progress

    Leave a comment:


  • DougM
    replied
    Originally posted by FusionKing View Post
    ...And just so you know 4943 actually lists wheels right on the box!!
    Chilly. 4943 it is, then.
    Stopped by the local Miller dealer yesterday to verify that he carries 4943, but he didn't have any in stock due to a rush on the stuff recently, and he didn't have the correct drive roll. Plenty of online places to procure a roller.

    Picked up two junk, cast scooter wheels and other pieces yesterday, so I'll be an experimenting fool for a few, at least with the .035" 4043 I have laying around. Probably will work like crap because it's been in the spool gun for who-knows-how-long, but perhaps still good practice.
    Was able to adjust the spool gun to spit out the 4043 well enough with the .030" drive roll.

    Anyway, thank you all for all the info. Very much appreciated!

    Leave a comment:


  • FusionKing
    replied
    If you buy 4943 then yes switch to .035.
    And just so you know 4943 actually lists wheels right on the box!!

    Leave a comment:


  • DougM
    replied
    Thank you FusionKing for taking the time to respond!
    No, haven't been able to source any 5083 in the thickness required anywhere locally (Winston-Salem, NC area). 5052 appears to be readily available.

    The mechanical issues with this design are that the proposed tow line (7/64" Dyneema) is quite slippery, and therefore distributes it's tension throughout more wrap layers than any other line-type would. For every other aspect of the tow, the Dyneema is the most preferred tow line due to it's very high tensile strength, low weight, high abrasion resistance, and very small diameter (low air-drag). Because of the accumulated radial and axial loads put upon the rim (compression) and side plates (bending moment) from the many high-tension layers of tow line, the side plates have a tendency to deflect outward if the spool is under-built. This is a common occurrence of other scooter winches. Not a huge factor if the side-plate deflection is small, but there should not be any interference with the trailing arms and the spool sides, obviously. Others have used 6061-T6, but I think they merely used what was most easily available to them without any real understanding of the material properties after welding.
    Both 5052 and 6061 appear to have comparable resistance to corrosion in wet environs, with 5052 perhaps a bit better. As the tow line can entrain moisture from towing on humid days, a long storage period could result in poultice corrosion if not insulated with some impervious coating (epoxy paint?).

    Currently, the gun has the .030 drive roll installed. Would you still recommend going to .035?
    Thank you!
    -doug

    Leave a comment:


  • FusionKing
    replied
    Doug,
    If you clean the wheel up, and then turn it to the proper shape, facing all welding surfaces, then it will weld like a dream. Providing it is standard cast material without zinc.
    5083 plate is going to be a bit hard for you to find unless you are near the coast. It is a salt water alloy as is 5086. both are very hard. And expensive.
    Locally you will likely find 3003 or 5052.
    3003 is cheaper than 5052 but 5052 is harder. 5052 is reasonable and good to work with. 6061 will loose most all of it's temper after welding
    6061 is more expensive but a better chemical match most likely. That is assuming the wheel is 356 or similar. Then 4943 is the best filler.
    In your case none of this is critical. It's more about getting a lot of cable on the wheel without getting tangled up.
    I like the idea of widening the rim by rolling flat rings. If I was forming rings then I would use 5052 instead but still go with the 4943 filler.
    As for filler size you should use .035 based on your experience. It will spray at a lower voltage and be more easy to control. I would and I have everything at my disposal...alloys and sizes.
    Tack all your pieces at least every 2 inches everywhere before final welding. Fit-up is critical
    I would knock the bearings out and turn that thing down (on a lathe) then make my pieces, put the bearings back in and rotate it around in a vice on a bolt to weld it.
    I would also consider thicker material to make a nice rounded inside edge to aid in loading the cable back up. If you did a nice enough job you could put it back on the lathe, and turn it down, and you wouldn't be able to tell it was fabricated.
    If you go on my Facebook page there are several photos in the photo gallery of cast ATV swing arms we have extended using 5052 plate.
    These we done for years using both 4943 and 4043 filler and have seen extreme abuse without any known failures. After final welding they were extremely hard and durable.
    These are my thoughts about how I would go about it if I were to tackle this project..... YMMV
    I hope this helps.

    Leave a comment:


  • DougM
    replied
    Thank you Red. Excellent information. I was thinking in similar circles about the Mg content of the cast Al after reading a bit more. Thanks for reinforcing that. I may not weld the side plates directly to the rim lips, rather cut off the rim lips all the way to the rim, then have some 0.25" plate that is 1" wider than the rim, rolled to the diameter of the rim, weld the rolled part seam while on the rim, weld the side plates to the rolled part, then align, tack, and weld the rim to the new rim/plate weldment. May be a bit heavier and have more rotational moment, but then the side plates would be welded to same material, with a better known strength.
    Thanks
    -doug

    Leave a comment:


  • Red Seal Tech
    replied
    I'm guessing pre-coating is the same as cladding. In essence you are adding a layer of the filler metal to the surface of the cast which acts like a middle layer where a dilution of the cast and the 'softer' filler makes the welding to the plate material a little easier.

    Not knowing the metallurgy of the scooter wheel makes an accurate filler selection a little dicey. However, in a general sense, aluminum rims are an aluminum / magnesium alloy which means that a 5xxx series filler and plate would be your best bet.

    With that in mind, if it were me (and it's not, so take it as my own 2p) I'd go with a 5356 filler and 5083 plate. Both common, off the shelf items.

    Make sure you clean the rim thoroughly and wire brush it with a stainless steel brush only. Any oxidation or clearcoat will contaminate the weld area and makes for a messy result.

    As far as welding, the parameters I have certified for are 24v 250a with 5356 .045 wire, 100%argon at 25 cfh. I preheat to 70*c (150*f) and don't let my interpass temp go above 140*c. That's using an XR 30 and an XMT 350.

    The interpass isn't as big a deal with 5xxx material as it's not heat treatable. I'm just a little more cautious out of habit.

    Leave a comment:


  • DougM
    replied
    Thanks Ryan, yeah, I figured that post was gonna be a drag. Thanks for all the info.

    Leave a comment:


  • DougM
    replied
    Thanks Anarchy... Just as you suggest, I have planned on purchasing a junk cast rim and some scrap plate and playing with that until good and ready. I have pure Argon that I mix with CO2 for my ferrous welding tasks, so I'm good to go there.
    Just plugged in the spool gun and gave her a whirl without power, and discovered the drive roll has quite a bit of run-out. Haven't taken the drive roll off yet, but perhaps the shaft is bent, or the drive roll is not centered properly due to the two set screws. Don't know yet.

    I'm figuring 0.047" wire should be appropriate for the base material thickness.
    Thanks

    Leave a comment:

Working...
X