Welding spring-steel rock-rake tines

[Sodo]

I built this stick-rake using spring-steel rock-rake tines. Sometimes when I shove it deep into a bush and back out it grabs ahold of something unseemly and "PING" off comes a tine. I know tractoring excites you fellas.



(thats my old BX24, sold it for $700 more than I paid forit)

I've broken 5 tines now, and there are some gaps in my raking. Anyway since I have a welder and am inclined to use it at the drop of a hat, I want to fix these tines. If that doesn't work then I'll buy new ones. They're surprisingly cheap ($12 each) but welding is more fun.

I plan to weld some roundstock on each side to strengthen the weld area. Does anybody know how to re-heattreat a spring steel tine such as this? Material is 5/16" x 1" (made in Italy, it's probably 8x25mm). Gut feel is that without an oven heat treating is too much trouble and maybe just bracing it (very easy) is 'good enough'.

 

[Rocky J]

I took welding certification in school . I remember that the harder the steel the more you had to use the chipping hammer to keep the carbon moving when it was cooling. The carbon is even through out the piece, when you weld the heat draws it from the surrounding area making the weld harder and the area around it softer, as well it will elongate the molecules from running many directions to all aiming one way and freeze that way. So as you lift your welder off the weld start striking it with your chipping hammer to scare the carbon back and mix it up again and do not allow any cool drafts to come over the repair as it goes from red to black. We threw old welding gloves on top to slow the cooling. If the round stock is mild steel it will bend and hold your rake up and out of line with the rest.

 

[gwdixon]

I know this is not a technical fix but rather a "farmer fix". I just weld mine back together with a small piece of flat plate backing the weld area. Used 6011 on harrow tines.

The way I figure it, the rest of the tine can do the flexible stuff well enough for the tine to work close to how it should. It seems to have worked well over the years and lots of use.

Besides, at the reasonable price to replace your tines the welding experiment is worth the fun time. Where yours broke is really not that critical for dragging but is certainly a weak area that would be extremely stressed if the tine got hung up.

 

[Gary Fowler]

I have welded several of the tines on my landscape rake. I just put a v bevel on them and welded up with 7018 rod. No backer or reinforcement. They hold as well as a new one but will still break at the same spot if an immovable object is hung up on them. Every broken one I have had breaks where yours did.

 

[Sodo]

I took welding certification in school . I remember that the harder the steel the more you had to use the chipping hammer to keep the carbon moving when it was cooling. The carbon is even through out the piece, when you weld the heat draws it from the surrounding area making the weld harder and the area around it softer, as well it will elongate the molecules from running many directions to all aiming one way and freeze that way. So as you lift your welder off the weld start striking it with your chipping hammer to scare the carbon back and mix it up again and do not allow any cool drafts to come over the repair as it goes from red to black. We threw old welding gloves on top to slow the cooling. If the round stock is mild steel it will bend and hold your rake up and out of line with the rest.

Thanks for bringing that up, this rings a bell from materials science class. Had a perfesser whose specialty was the study of "Limited Solid Solubility". He was quantifying the travel of carbon molecules in steel, ----> while the steel was "solid" form. He said that at elevated temperatures the carbon molecules migrate around the steel. At cherry red carbon is moving around (in steel) at a measurable rate. He said carbon moves around at room temperature too ( ! ) although at an insignificant rate. ------> IIRC <------ (verification needed).

I know this is not a technical fix but rather a "farmer fix". I just weld mine back together with a small piece of flat plate backing the weld area. Used 6011 on harrow tines. The way I figure it, the rest of the tine can do the flexible stuff well enough for the tine to work close to how it should. It seems to have worked well over the years and lots of use. Besides, at the reasonable price to replace your tines the welding experiment is worth the fun time. Where yours broke is really not that critical for dragging but is certainly a weak area that would be extremely stressed if the tine got hung up.

Good to hear. I'm thinking that there must be a clever way to minimize stress at the junction of the doubler. So many farmers out there with welders someone must've figured out a way to do this. GW did you do anything special at the end of your doubler where you want the spring steel to take over? Gary good to hear they last reasonably well with no doubler.

 

[gwdixon]

GW did you do anything special at the end of your doubler where you want the spring steel to take over? Gary good to hear they last reasonably well with no doubler.

Well, now that my memory has been jogged, I did use a short piece of old tine as the backer. Even though welding crossways sets up a stress riser and HAZ it doesn't seem to cause a problem...technically, yes but practically, not really.

So like Gary, the break was V-ed out to get a 100% weld and the backer was simply welded crossways both ends. My first attempt was to not use a backer and failure was almost instant. Thereafter, and with a backer, all repaired tines have held.

But my tines are curved, almost in a circle, on a drag harrow. The tine broke at the top, about midway around the curve. Kind of hard to see in the photo below, but you can get the idea. Took me about a year to find the broken end of the tine. After several discings, there it was, sticking up in the air.

It appears from your broken tine that a backer would need a hole drilled and a longer bolt after the repair.

 

[drizler]

I made a landscape rake a while back using those type tines. My problem was that the holes were a tad smaller than the bolts I had so I drilled the holes out just a tad bigger on the tines. I heard that "twang" quite a bit more than I would like to have. Next time I am going to just weld em on and grind em off as needed, much much better. I really hate that twang sound............sounds like money flying away.

 

[Sodo]

I think I am going to add a 'limiter' so the tine can't bend at the bolt hole, force the bend to be a gentler curve and farther out.

 

[Big Barn]

I think I am going to add a 'limiter' so the tine can't bend at the bolt hole, force the bend to be a gentler curve and farther out.

I LIKE that idea.

Terry

 

[SSdoxie]

I have close to half-dozen broken off on my 6'. None are at the blot hole, all are somewhere in the bend or just above it. I would love to try and reweld them just to see if I could. My problem is they are all laying out in the pasture somewhere and have never turned up, all I have left is the piece attached to the rake. :thumbdown: