What rod to use on excavator hitch?

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A friend has asked me to do a little buildup on his 4 ton excavator hitch inside the front hook, where the front pin engages.Both pin and hitch are worn, but im only doing the hitch.  Told him to get a new pin.It needs about 4-5mm buildup.What rod would you use to build up in this application?  A 70,80,90 or 10 series rod or a hardface rod with heavy impact ability?
Reply:By "hook" I assume you have a QD bucket mount. Our slightly larger excavator had a fixed bucket and we just drove out the bushings and replaced them. I'll see if I can find out what they use on the loader QD's at a friends place..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:Originally Posted by DSWBy "hook" I assume you have a QD bucket mount. Our slightly larger excavator had a fixed bucket and we just drove out the bushings and replaced them. I'll see if I can find out what they use on the loader QD's at a friends place.
Reply:Larry, you might also post up on Mzone and see what Brent suggests. He's done a fair share of heavy equipment repairs..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
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Reply:Say Larry do you have a picture of the area  that you want to biuld up?Co-Own CNC shop:Miller :1251 plasma cutter, MaxStar 700 TIG/Stick, & XMT 456 Multiprocess Welder.&  2 Hypertherm HPR260's Plasma CutterSorry I had a bad stroke but now I am back.
Reply:Originally Posted by specterSay Larry do you have a picture of the area  that you want to biuld up?
Reply:Pics of area that needs build up. Attached Images
Reply:IF it were me,  I'd go for the 7018 or mig it with ER70S-6.   Don't know if thats correct or not, but has worked in the past on heavy equipment.My name's not Jim....
Reply:I suppose if i was to use hardface, that it would be hard to re-shape properly.I have both 7018 and ER70S-6 and hand.Just wondering if they will hold up good in that situation/load.I just dont want it to hammer itself out again in a couple of months and the bloke come back and tell me its a crap job.DSW had a friend suggest a 8018 rod that he uses on his heavy equipment.The excavator is only 4ton so i would not call it heavy machinery.
Reply:I like 7018 and ER70S-6 because when it wears, you can go right back over it again.  That's not the case with hardfacing.  I've burned hundreds of lbs of  7018 and ER70S-6 building up Labounty jaws and loader buckets.  If I was to use hardfacing, it was sparingly.   Maybe a few X's here and there.My name's not Jim....
Reply:Thinking about the hardface, it would probably wear out new pins very quick as well.He/friend has his heart set on hardface for some reason, even though he dont weld.When i suggested today about welding with ER70S-6 or a 7018 he had a puzzled look on his face.I think that maybe i'll do it in 7018, keep rods in the oven ( i alway bake my 7018's ) and tell him that they are special for that application.Hardface is out..
Reply:I wonder if you could add a block to the coupler, which would distribute loads over a larger area of the pin?I'd suggest being straight with the customer about the electrode type you use. The key to a lasting repair will be in having smooth and well finished contact area between the pin's radius and that of the build-up.Good LuckLast edited by denrep; 03-19-2010 at 07:13 AM.
Reply:Larry there is a 7024 rod made by hobart that works well for resurfacinghttp://www.constructionequipment.com...ment/8498.htmlCo-Own CNC shop:Miller :1251 plasma cutter, MaxStar 700 TIG/Stick, & XMT 456 Multiprocess Welder.&  2 Hypertherm HPR260's Plasma CutterSorry I had a bad stroke but now I am back.
Reply:I'd use the ER70 mig.  The bigger question (or maybe you've already got an answer for it) to me is how are you going to get it shaped right after you weld it?  Were you planning on having someone set it up in a mill and bring it back to factory size?  Some of the old timer's would weld up draw-bar hitches with a chunk of carbon rod in there to maintain the round hole.  I suppose a big chunk of copper or brass would do the same.Miller 250x & Lincoln V205-TSmith Oxy-Prop torch
Reply:Yup,  mill it is.I have a friend that has an engineering shop that is going to mill it for me
Reply:Originally Posted by denrepI wonder if you could add a block to the coupler, which would distribute loads over a larger area of the pin?I'd suggest being straight with the customer about the electrode type you use. The key to a lasting repair will be in having smooth and well finished contact area between the pin's radius and that of the build-up.Good Luck
Reply:Use a buildup rod/wire.   Goes on somewhat denser and harder than any standard welding electrodes, but still grindable/machineable.  Won't be harder than the pin material, though.Problem with any welding electrodes (7018 etc.), they tend to mushroom out under pressure, especially in metal to metal applications.
Reply:Originally Posted by BoostinjdmIF it were me,  I'd go for the 7018 or mig it with ER70S-6.   Don't know if thats correct or not, but has worked in the past on heavy equipment.
Reply:Originally Posted by jsfabUse a buildup rod/wire.   Goes on somewhat denser and harder than any standard welding electrodes, but still grindable/machineable.  Won't be harder than the pin material, though.Problem with any welding electrodes (7018 etc.), they tend to mushroom out under pressure, especially in metal to metal applications.
Reply:If it were me, I would use a build-up rod as they are made for this type of application. They are a little bit harder in ductility as the tensile strength is usually around 90,000 psi. They are very good for "buttering" passes and build-up. I've even used them for repairing cracks on heavy equipment because of the tensile strength in a jam. They also come in a wire for using with gmaw. I dont know if the brand "Arctec" is in your area but they make a rod called "223 buildup" and it will work for you. But 7018 will do the job as well. Dont hard face this area as you will wear out your pins and it will be a bitch to get off once its on.
Reply:Oh btw 7024 is not a surfacing rod. It is an aws welding rod and is using in the flat position because the iron powder in the flux.
Reply:the last repair I did like this was to take a 1 inch plate and cut it the needed profile on two pieces.  I sistered one on each of the original hooks on the inside.  The intent was to distribute the load over the wider surface.  The only rods we had were 6010, 7018, 7024, 309 and 316.  I did all the add on with 6010 and 7018.  I then was asked to butter the hook with 309.  I am not suggesting you do the same, just commenting on how I was asked to make a similar repair.  If this is wrong I would like to hear it and understand why, but the repair worked and is still in use.
Reply:Originally Posted by weldersdoithotterIf it were me, I would use a build-up rod as they are made for this type of application. They are a little bit harder in ductility as the tensile strength is usually around 90,000 psi. They are very good for "buttering" passes and build-up. I've even used them for repairing cracks on heavy equipment because of the tensile strength in a jam. They also come in a wire for using with gmaw. I dont know if the brand "Arctec" is in your area but they make a rod called "223 buildup" and it will work for you. But 7018 will do the job as well. Dont hard face this area as you will wear out your pins and it will be a bitch to get off once its on.
Reply:Hi Larry you may want to ask your local Welding Industries of Australia representative what he would recommend. WIA is located throughout Australia their catalog is http://www.mgis.com.au/WIA_catalogue_2002.pdf   If you tell them the excavator hitch machine info they can match you up with something like a McKayTube Alloy welding rod or MIG wire. That will deposit a high chromium content alloy with a Rockwell Hardness of 55-62 yet still be machinable. A couple of years ago we used that welding rod to extend the life of the gear teeth of Hanson Aggregates and Elam Sand and Gravel's rock crushers. I use the same welding rod on my Ford New Holland 555E backhoes rock bucket as well construction equipment for New York State Dept of Transportation equipment.Co-Own CNC shop:Miller :1251 plasma cutter, MaxStar 700 TIG/Stick, & XMT 456 Multiprocess Welder.&  2 Hypertherm HPR260's Plasma CutterSorry I had a bad stroke but now I am back.I would stay away from anything containing chromium. That stuff is bad news if you dont have the proper breathing protection. It is very toxic and causes stomach cancer. It also collects at the base of your spine as its very heavy. Use a tungsten carbide if you have to. But in this application i would use neither. Why would you? These are added to hard surfacing rods and that would defeat the purpose off why the wear on your machine is located where it is. When companies design this stuff its for a reason. The pins on you shovel are most likely an alloy steel and will be harder than the steel on the machine. They do this because it is cheaper to build up parts than to cut the shovel apart and rebuild with new components. This is why you should not put a anti wear material on the machine. If you want to mig it fine er70s will work 7018 will work so will 90 or 110 you do want a tough material going in there but still soft enough for the weld material to wear first.
Reply:Originally Posted by LarryOA friend has asked me to do a little buildup on his 4 ton excavator hitch inside the front hook, where the front pin engages.Both pin and hitch are worn, but im only doing the hitch.  Told him to get a new pin.It needs about 4-5mm buildup.What rod would you use to build up in this application?  A 70,80,90 or 10 series rod or a hardface rod with heavy impact ability?
Reply:Hi Mate  today 3-21-2010  Usa    These guys are right to use a build-up rod or wire. we use stoody build-up lh or 7018 either one is ok.   After looking at your pics I would build up all the way across  and then line bore for new pin dia. making a .005-.010 fit over bore.  In our shop we set up our line bore for the pin center first. Then we build up using our bore welding machine,adding enough material to fit the new pin size. Then bore to fit new pin.I am aware that not everyone has this convient set up. But it sure is SWEET.
Reply:Originally Posted by farmersammWhat have you used with success.  I'm facing the same ANNUAL repair again shortlyThanks Joe
Reply:btw The method too use the bore weld is to start weld then stop at the open area then start again.  I know you knew that right.this is for those who are not familer with what were doing.THANK YOU ALL for understanding.
Reply:Originally Posted by jsfabRankin, Stoody, and Postle Industries make some very good build-up products.  Postle in particular, makes several versions, to fit different applications.  Best thing to do is call the company, I've always found the engineers to be very competent and helpful.For whatever reason, have no experience with Lincoln build-up.
Reply:Originally Posted by BoostinjdmI like 7018 and ER70S-6 because when it wears, you can go right back over it again.  That's not the case with hardfacing.  I've burned hundreds of lbs of  7018 and ER70S-6 building up Labounty jaws and loader buckets.  If I was to use hardfacing, it was sparingly.   Maybe a few X's here and there.