welding a spring tooth tine

Can the tines on a spring tooth harrow be welded? I've got a couple of the same tines on the rear section of my cultivator and both broke at a bolt hole. Could a patch be welded on to get some extra welding area?

A spring is made of heat treated steel. When you weld it the heat can/will anneal the spring material reducing it's strength by approximately half that of the heated treat material. Welding extra material to re-inforce the break simply increases the annealed area. It may not break at the reinforced area but it is likely to break where the re-inforcement stops and the spring material is annealed.

A proper repair (expensive) would go something like: anneal the entire spring, weld using filler metal compatible with the spring material, heat treat and temper.

Since I am sure you are going to weld the spring, the above will be of little use to you. A suggestion, after you weld the spring, fabricate a steel plate that will extend 3-4 inches on either side of the welded mounting hole. Drill a hole in the plate for the mounting bolt to extend through and place it on top of the spring such that it supports the spring when it is bending. The plate acts like a one sided split on a broken bone and supports the spring in a non-heat affected area. Note, since the plate effectively makes the spring shorter, the remaining spring material is less able to move out of the way for large rocks etc. Therefore, it will likely have a shorter life than a non-welded spring.

Cut a diamond shaped piece to reinforce it. I built a trailer with leaf springs shortened that way about 40 years ago. Never broke. I welded it with 308 stainless rod.

One time I welded a torsion spring for my neighbors garage door, and it lasted a quite a while, I used Eutectic 680, a very special rod.

I agree with Indiana Ken, weld it and splint it.

Nothing to loose by trying.

Go ahead, as others say you have nothing to loose. When you weld on the backer just Weld along the sides and not across the shank, that should help some. Good luck tho, as welding springs is a tough deal to do successfully.

Hello Charly M,

I would plate it at the hole, and preheat before welding. Low Hydrogen rod should be sufficient. Root and cover pass between the two pieces. The plate can be done with one pass with the right size wire,

Guido.