Welded cast parts on sickle with a MIG!

[Sodo]

I bought an old Massey Ferguson MF-31 Sickle mower for $150 (?). It was a challenge to get it going, the main wobble box shaft was broken and I welded it with my MIG. (Story Here)

I've been using it and decided that I like a sickle mower! Time to replace some wear parts though ("past" time!). I located the replacement guards and sickle knife sections at Webbs Sickle service and they were very helpful, but unable to provide the sickle-bar hold-down clips. So I bought the parts that they had, and resolved to keep looking for hold-down clips.

Well now the grass is growing, and I have not found any hold down clips, so decided to repair them. I know a bit more about welding cast iron now, but still wondered, if i'm just adding a wear-surface, why not see what happens just welding it with the MIG?

Welding cast steel with a MIG may be illegal in seventeen states but I did it anyway, and it's FINE !

Installed the new guards. Paint is worn off because this pic was after I used it.



Heres a pic of the worn-out clips. You can see that the sickle bar is almost touching the bolts.



Ground off the rust and opened it up a little.



Welded a 1/4" rod into the worn out section of the clip. Also added some steel to the 'finger' on the hold-down clip.



Ground it flat again.



Here's what it looks like installed. I am on the lookout for replacement clips. But it's not all that urgent as the mower is working great.

 

[Baby Grand]

Impressive repair, Sodo & looks like it should work fine.
Using the 1/4" round stock was very smart - you wind up with a nice edge without any machining.

 

[Gary Fowler]

I have welded a lot of cast steel using 7018 rods and they hold as good as new. On my Yanmar tractor, the bolts that hold the lift arm bracket to the rear axle continuously worked loose and I finally lost the bolts so I just welded it solid on to the bottom of the tractor axle. No more lost bolts, and it held together till this day and I pulled an 8 foot 1500+ pound disc with it many times. My brother in law still uses it with the Howse bush hog that I sold him.

 

[Gary Fowler]

I forgot to mention that the last time the bolts came out it buggered up the threads which is why I just welded it rather than try to chase the threads and get new metric bolts and I got tired of buying $$ each bolts.

 

[rswyan]

... I know a bit more about welding cast iron now, but still wondered, if i'm just adding a wear-surface, why not see what happens just welding it with the MIG?

Welding cast steel with a MIG may be illegal in seventeen states but I did it anyway, and it's FINE !

Cast iron and cast steel aren't the same thing ...

 

[Gary Fowler]

Cast iron and cast steel aren't the same thing ...

That is true. To me cast steel welds no different than low carbon steel. It isn't as brittle as cast iron and much stronger.

I have also welded some cast iron with 7018 with good results. In some instances there is no need for the high nickel content rods for welding cast iron. Mostly it depends on how the material is shaped. An intricate design is hard to weld together due to the expansion and contraction ratios of the parts. A solid thick piece welds pretty easily and wont crack out like smaller pieces even with 7018 electrodes. Proper pre-heat and post weld cool down is critical.

 

[Sodo]

I suspect this is working out because the parts are small. I would have preheated but my torch was out of sorts, and,,,, the parts are small, seemed like it would work out.

I "fixed" all 9 clips, the one pictured is the worst one. I know you guys like carnage.

So it must be cast steel - if it welded OK? Also it doesn't seem like original part would be strong enough if it was cast iron. I need to find some cast irin then and try a bead on it. Like a spark test, i suppose you could use a welder to identify cast iron .vs. steel.

On the hold down finger, you can see the puddle oxidized a little, its really thin there, puddle was really HOT. On some of them it almost fell thru.

View attachment 425199

The weld behaved better when I could dwell a little longer on the steel rod & drop off onto the cast then get back on the steel rod.

 

[4570Man]

A tried welding some cast iron with a stick and a mig. It welded nice but wouldn't hold.

 

[Sodo]

A tried welding some cast iron with a stick and a mig. It welded nice but wouldn't hold.

How big was this chunk of cast? How thick was it in comparison the the bead size?

 

[rankrank1]

Nice work on repairing those cast hold downs but is there a reason the common run of the mill universal stamped steel sickle hold dowms from TSC, Rural King, Webbs would not work?

Anywhere from $4 to $5 a piece at TSC (and likely even cheaper everywhere else).

copy and paste links here:

Low Arch Hold Down Clip, Pack of 2 - Tractor Supply Co.

or

Hold Down Clip, 2 lb. - Tractor Supply Co.

Course now that you repaired those others, I would wait for them to be worn out again before replacing....or at least worn some. Typically as these hold downs wear you can hit em with a hammer to tighten the the hold down again some. Your welded ones may have lost some of their mallable properties to be bent down again without cracking but will still last quite a while as repaired.

PS: I have welded unobatainable caste iron parts with flux core E71T-11 wire feeder on my old hay rake and they have worked fine for years now. One of my hay rakes is a 1938 the other is a 1948. Migging with gas I am quite sure would have done it even better than flux core. Part of my success was the high quality of the vintage john deere cast from the 1940's which supposedly already had a lot of nickel in it or so I have heard. If it had not of worked it was off to the junkyard or fencerows in search of used parts so I really had absolutely zero to lose other than my time. I even used a 115 volt wire feeder to do it too (although a top quality 115 volt unit - no junk).