how fast welded rods?

[young gun]

What is a safe rpm limit to spin welded rods? They are JD rods

 

[CLIFF S]

It cost less to do billet rods 1 time than it does to fix the tractor and do it over!

Seen too many blocks with holes in them!

Save your money and do it right the first time!

Much Safer too!

Cliff S

 

[Dane B]

Cliff, that's what I'm debating...wether or not to replace my welded with billet. I'm leaning that way to give motor longevity. Thanks

PS, I am the young fella you met down at blue ball this summer if you recall.

 

[VicS]

The spindles on the back of your 3/4 and up truck are welded on. If they are done right! they are as strong as the metal can be. We have some in a WC I have worried about them for over 10 yrs. We did get them heat treated again.

 

[ppmengineering]

We make our own welded rods for our 2 cylinder Deere's. Six pairs. Last time we broke a crank, it broke at number one journal and the flywheel tried falling on the track still attached to the crank and rod. Bent the rod 45 degrees but never broke. Jig welded and fully plated. I'll see if I can find it and post a pic.

 

[jdth]

I"ve had welded rods for 15 years+. The first one is still together & don"t worry a bit about it. The second has been together for 10 years+. This tractor broke in half in IA 8 years ago, it was put back together with the original crank & rods, still pulls well. The bearings are replaced yearly & currently show an even wear across. If the person welding the rods knows what they are doing & perform the job correct, you will not have an issue.

 

[southpull]

What Vic said. A welded rod done right won't fail because its welded. it may fail and bend because it's not strong enough or fatigue over time. We've got to remember almost every one of us are using welded cranks with great success.

 

[Dane B]

Cliff, that's what I'm debating...wether or not to replace my welded with billet. I'm leaning that way to give motor longevity. Thanks

PS, I am the young fella you met down at blue ball this summer if you recall.

 

[FactoryFarmer]

I built a set of rods for my G and then sent them to Derek Holdren to get them really perfect and box them (I don't own a TIG) I spin it 3000+ rpm and have not had an issue. My old engine I spun 2500 or so with welded rods and then had an issue either.

 

[Tater]

I spin my welded rods as hard as it will. I've had more problems with the block and sleeves.

 

[Robert Major]

The rev limit on welded rods, is a few RPMs before it snapped and came out the side! Kinda like my buddies unlimited puller, when guys asked what the rev limit was. Always told them rev limit was when it came apart. guess they had no concept of what unlimited meant l.o.l.
I guess really it depends on the weld and if the rod had a casting fault, or hair line crack before it was done. way to many variables to tell I think.
Regards Robert

 

[baldwin racing]

I ben thinking about this for a while as well.....I wanted to do a set and a couple engine builders said I was nuts others said your more than capable....I was going to make a jig that holds them solid I have a tig,I was going to preheat them in oven pull out tig weld them up and put back in and keep doing this until completed...what process did you use?..my other? is what should you box them up with 4130 plate? or 4140 what do you guys use? mild steel this would be a smaller stroke motor with a good rod ratio....I know some engine builder that know me are saying are you nuts? lol I'm shure the text will be rolling in tomorrow....
Thanks kelly

 

[MO SUPERM]

bought a tractor already built didn"t seem to be running right after a few pulls tore it down had welded rods in it couple of them were bent or welded wrong other things done cheap replacing everything with baker products might be a little more costly but will be done right this time

 

[wi50]

I've welded rods. Just made a simple jig from a heavy piece of material with holes at the center to center distance. I machined plugs to fit the rod bores and left a step to hold the small end the correct height. V them and tig weld, I just boxed them with mild steel. Your old forged rods are nothing stronger than mild steel anyway and when you cut them apart look at the cross section, they just are not that strong. Try to weld as close to the wrist pin end as you can. They have held up well past 4000 RPM in the engine they were in.

I've also lengthened or shortened rods a slight amount by making a plug to fit the end with a center in the plug, welded the plug in. Made a plug to fit the big end and bolted it to the mill table, then I can find center of each plug in line and move to the new length to bore the hole.

 

[north puller]

Why weld as close as possible to the wrist pin? Why not the
middle somewhere? Is the small end under less stress?

 

[DAVE Thompson jr]

My uncle has pulled for years and used welded rods. They seem to have held up for him. I wouldn"t use them I believe there is to much to risk. I can guarantee you that the better engine builders like Gary Baker and Paul Marlett wouldn"t even think of using welded rods. If you are going to have 10 to 20 thousand in an engine the extra money for good rods pistons and a good crankshaft would surely be used. My uncle claims to have welded rods in his Moline and has hooked it many hundreds of times but ive never actually seen what is in it. Just my opinion.

 

[young gun]

Thanks for all of your replies and input, especially those who answered my question (although all opinion).

To clarify, my engine build is complete and has welded rods in it right now. I was wanting to know an approximate rpm range to still be comfortablely safe spinning these rods. They are boxed in welds.

Also, seeing as I am young, I don't have countless thousands to invest into this or any tractor; not that I'm cutting corners , but I decided the welded rods was a good route for me to go at this point in time.

Dave, I agree with you, however, my build was around 4-5000 so another 1000+ for billet rods is 20-25% more of my total expenses. Whereas someone spending 20,000 on a tractor, the 5% extra cost for billet rods is definitely worth your time.

Thanks again for all input.

Dane

 

[mike f]

From my experience with welded JD rods.. I used them and never had any issues, I even ran the 9" crank to a stall many times. the motor had very high cranking pressures at first startup as I got sent the wrong pistons.. we saw cranking pressures of 340psi. I actually ran it for two pulls before losing the head gasket. If welded rods took that, they will take about anything IMO. I would be more worried about the crank breaking at the rod journals than splitting a rod. I am sure other JD guys will chime in.

 

[buickanddeere]

(quoted from post at 15:46:18 01/04/14) From my experience with welded JD rods.. I used them and never had any issues, I even ran the 9" crank to a stall many times. the motor had very high cranking pressures at first startup as I got sent the wrong pistons.. we saw cranking pressures of 340psi. I actually ran it for two pulls before losing the head gasket. If welded rods took that, they will take about anything IMO. I would be more worried about the crank breaking at the rod journals than splitting a rod. I am sure other JD guys will chime in.

Changing the cam instead of pistons to solve the high cranking pressures would have been a win win solution.

 

[buickanddeere]

(quoted from post at 22:57:37 01/03/14) I ben thinking about this for a while as well.....I wanted to do a set and a couple engine builders said I was nuts others said your more than capable....I was going to make a jig that holds them solid I have a tig,I was going to preheat them in oven pull out tig weld them up and put back in and keep doing this until completed...what process did you use?..my other? is what should you box them up with 4130 plate? or 4140 what do you guys use? mild steel this would be a smaller stroke motor with a good rod ratio....I know some engine builder that know me are saying are you nuts? lol I'm shure the text will be rolling in tomorrow....
Thanks kelly

The mild low carbon steel probably saved the project. It ductile enough to flex a little even after the heat of welding.Instead of being being brittle and breaking.

 

[20MuleTeam]

factoryfarmer, Is that the 3000 rpm G that's really only 1800 rpm?

 

[DAVE Thompson jr]

What kind of power did your tractor make on the dyno. Rpms doesn't meen everything. Its what power you have at the end of the track that matters. Many tractors take off screaming and power stall. Put it on a dyno and see what you have on the lower end that is where it is at. If it doesn't lug its not worth owning. Just my opinion.

 

[Michael Bay]

Billet is way to go if you don"t want to worry about it. These are what we made for our 9.25 A

 

[case 1175 puller]

How long are those rods?

 

[Michael Bay]

Long haha I'll check print and let you know

 

[Michael Bay]

14.25 center to center

 

[buickanddeere]

Excellent built in cam clearance there.

 

[Michael Bay]

Thanks

 

[elkcagg]

The reason you want to weld the beam closer to the wrist pin is because when rods break they usually snap the beam nearest the crank journal portion. This area is the portion of stress called vector loading. Vector loading is simply the transfer of power from reciprocating to rotating motion.