What is the best way to Weld up these Holes?

Discussion in 'Workshop Tips and Secrets / Tools' started by Armilite, May 23, 2018.

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  1. May 23, 2018 #1

    Armilite

    Armilite

    Armilite

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    Any Pro Welders here. What is the best way to Weld up these Engine Case Holes, Mig, Tig, etc? I want to Weld up and then install these Steel EZ Lock Inserts. Inserts are inside 8mm - 1.25 and outside 1/2" - 13 I think.
     

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  2. May 23, 2018 #2

    Chris In Marshfield

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    I haven't any experience welding cast parts, but Jody does. Does this give you any ideas?

     
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  3. May 23, 2018 #3

    Chris In Marshfield

    Chris In Marshfield

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    Here's another one he did on welding icky cast aluminum:

     
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  4. May 23, 2018 #4

    pictsidhe

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    First, strip the parts completely and degrease. Any oil will kill your chances. If you just want to repair threads, you may be better off not welding and using helicoil inserts instead.
     
  5. May 24, 2018 #5

    CameronB

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    I asked Jim at the Lincoln welding class about welding old cast aluminum last year. He said a lower frequency worked good on dirty cast. I set my machine to 50hz and it did fine. Do you have a TIG?
     
  6. May 24, 2018 #6

    proppastie

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    You may warp the engine, might be better to put a large threaded insert in the existing hole, then a smaller insert inside the first one until you get the size you want.

    As I understand it when they weld repair an engine case (Divco) they then shave the halves and re-bore the crank main and cam bores.
     
  7. May 24, 2018 #7

    TejasNW

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    If you are welding an aluminum case, you are looking at TIG on A/C process. Use the "4T" process with enough upslope to clean the material of contaminates. Mig can weld aluminum but the cleaning, penetration, and contamination control is not on par with Tig. A used engine case will not respond as well to Mig.

    Here is a pretty good primer, if you are not familiar with TIG: http://www.weldingtipsandtricks.com/tig-welder-settings.html
     
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  8. May 24, 2018 #8

    TFF

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    I worked for a shop that repaired cylinder heads a long time ago. Welding plenty of cracks. Aluminum was TIG and stick. We would heat the heads in a BBQ grill. A hole has not a lot of space to work with, without some grinding to open stuff up. I'm inclined to say stick. Have the machine set and off, get the rod set in the hole, and have someone turn it on. Depth without grinding will be hard for every way. Why not regular thread inserts?
     
  9. May 24, 2018 #9

    don january

    don january

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    Been there done that! the problem I had was to get the puddle down deep enough into the old hole and when I did get it the heat was so high I seen color change in the case and I'm sure warp edge was there also.
     
  10. May 24, 2018 #10

    Armilite

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    Rotax doctored some case holes so they wouldn't be easy to convert. Most people in the past have just welded them shut, redrilled and tapped the hole, didn't even use an Insert, and some case's they even milled off one boss, so they had to weld on a chunk and then machine it. A Tool & Die guy years ago reccomended those EZ loc Inserts. I have thought of using and Insert, inside of an Insert, or make my own custom Insert. It's for the Gear Drive so you really can't go to bigger Studs/Bolts. Each Hole is a little different case to case. I'm afriad if I just try to thread it for a bigger Insert I'll make it weaker. Welding up and using an Insert seems the best option. I got a bad case to practice on.
     
  11. May 24, 2018 #11

    Armilite

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    Don't have a Tig yet, got a small 135 Mig and a Lincoln 225 Stick, but I got it ordered, a Vulcan 220 is coming any day, it's a combo unit Mig, Stick, Tig with foot Pedal. I just never welded Aluminium before, I'll have to practice on some scrap case's I have kept around for just this reason.
     

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  12. May 24, 2018 #12

    Armilite

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    Yea, I have thought of using an Insert inside of an Insert, and even making my own Custom Insert, but I'm afraid I'll weaken it to much. Most People have just welded the holes shut and just redrilled and tapped the holes with No Insert. That's an option that has worked in the past. A Tool & Die guy recomended using those Ez Loc Inserts which maybe over kill. When my welder comes I may exsperiment with both ways, with and without Insert in on my Scrap case.
     
  13. May 24, 2018 #13

    Armilite

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    Thanks for the link I'll watch them tomorrow.
     
  14. May 24, 2018 #14

    Armilite

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    I can Glass Bead the Front and the Holes and then wash it with Alcohol to clean it well. I was wondering if that was an option, I even thought to clamp the case to a rotary table and have someone turn it real slow. The holes are about 3/4" deep.
     
  15. May 24, 2018 #15

    Armilite

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    Ok, yea I may try using a lower setting, I have some case's to practic on.
     
  16. May 24, 2018 #16

    Turd Ferguson

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    Clean it up, TIG weld the holes solid, re-machine face, lay out bolt circle, located holes on bolt circle, drill and tap.

    Is there any reason why thread inserts have any kind of advantage over simply drill and tap aluminum?
     
  17. May 24, 2018 #17

    proppastie

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    Welded aluminum is soft...the larger insert will allow for higher strength because the OD thread is lots larger than just a tapped hole in soft aluminum. It might depend on how much stress one expects the bolts to see (vibration, & torque analysis & power pulses ? ) Or you can just tap the holes and if there are problems down the road then put the inserts in.
     
  18. May 24, 2018 #18

    Turd Ferguson

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    Good theory. Weld definitely has less strength. I think that applies to inserts or the actual fastener. More surface area because it's larger diameter? Will just tear out a bigger hole.
     
  19. May 24, 2018 #19

    proppastie

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    not sure why a through bolt "body bound" if necessary in the existing holes is not the best option. I must be missing something here.
     
  20. May 25, 2018 #20

    pictsidhe

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    Since welding Al is not one of my stronger points, I'd thread some suitable Al bar stock and JB weld it into drilled and tapped holes. Then drill and tap my nice 6061/3 inserts. I also suspect that holes may not be the ideal place to learn Al welding?
    I've had decent results with the Al/Zn soldering stuff, with large inserts, that could work OK.
     
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