What Rod for Welding 4640

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I need to rebuild the carpet pole attachment (again) for the fellows that took over  my business.   It worked perfectly fine for the six years I used it, but I digress...Anyhow I am replacing the pole with a 14 1/2 foot length of 3 inch diameter 4640 solid round stock.  Should weigh under 350 pounds. I plan to preheat and stick weld.  What rod(s) should I use ?   I can't seem to find any info online. Here's a photo of it after the initial build. The now BENT pipe will be replaced with the 4640 solid stock.

tia:
Reply:I wanna watch, please post more pictures!Retired Old GuyHobart 210Lincoln AC/DC 225/125 Evolution 14” Saw
Reply:"WeldingSuccessfully welded by common fusion and resistance methods, this alloy should not be joined by oxyacetylene welding. AWS E/ER630 filler metal is recommended if required."found this on https://www.steel0.com/AISI_4640.htmnot sure how helpfull that is.  Might be different since its being welded to what i presume is mild steel yeah?
Reply:C555_LawsonWeldingTechGuide_AD.pdfthis states it should be preheated to 600-800 degrees fall the input i can give tho. No personal experience in this matter.Last edited by Zephariah; 10 Hours Ago at 05:12 PM.
Reply:

Originally Posted by Zephariah

"WeldingSuccessfully welded by common fusion and resistance methods, this alloy should not be joined by oxyacetylene welding. AWS E/ER630 filler metal is recommended if required."found this on https://www.steel0.com/AISI_4640.htmnot sure how helpfull that is.  Might be different since its being welded to what i presume is mild steel yeah?
Reply:just got a hold of my friend Bob who says preheat and 223xc rods. looks like i will have to buy a pack unless someone here who's dealt with 4640 can tell me otherwise.:
Reply:Sounds like one of those " magic" electrodes sold by companies like Lawson or chematron. My go to for different alloys that are somewhat unknown has been 80 or 9018 with preheat, at least 250f and not exceeding 500f on interpass temperature and then post heat to about 300f and as slow a cool as possible.
Reply:This Chinese website recommends E630 for welding 4640 steel.https://www.steel0.com/AISI_4640.htmhttps://www.duramaxwelding.com/product/e630-16/ I'd think the 223XC rod would be fine too, anything for medium carbon steel would likely do the job.Never welded 4640, but I have welded 4340 and they look pretty similar in terms of composition. I'd think anything that works on 4340 would also work on 4640?