OK , so I know that if not properly stored and kept dry this 7018 I've got is no longer "low hydrogen" . What I'm wondering is what other properties are altered and how it affects the weldment properties . I've just ordered another 5 lbs , and I'll be more careful about how I store it . Probably use a piece of PVC pipe with a cap on one end and a threaded plug in the other . And while I'm at it I think I'll make some tubes for the TIG wire .
The hydrogen dissolves into the molten steel and causes embrittlement. Porosity too as some of the dissolved hydrogen will come out of solution as the weld solidifies. Eric
OK , so I know that if not properly stored and kept dry this 7018 I've got is no longer "low hydrogen" . What I'm wondering is what other properties are altered and how it affects the weldment properties . I've just ordered another 5 lbs , and I'll be more careful about how I store it . Probably use a piece of PVC pipe with a cap on one end and a threaded plug in the other . And while I'm at it I think I'll make some tubes for the TIG wire . Snag
=====================================
The procedure to dry it is pretty much spread it on top of the wood stove.
I knew I could count on you for a solution ... I'm a lousy stick weldor , my beads look like gobs of pigeon crap . But shit sticks together , so I'll keep on keepin' on . I'm not doing anything man-rated , and I'm careful to stay out of the likely impact zone if something fails . It appears that the recent modifications (which included stick welding with 7018 - vertical up) to my firewood handling system has made me at least twice as productive as compared to me actually lifting bigass chunks of log .
Hiya Snag, everyone Your question was "what else is affected?". For a start - modern weldable structural steels are highly immune to hydrogen (low Carbon, homogeneous composition and constitution (microstructure), etc.). A 7018 will absorb water until it gives a hydrogen level about the same as a 6013. 6013's would be OK - hydrogen cannot be an issue... So it's a big subject, but when using modern steels you are hardly likely need any concern about hydrogen. BTW if you could use a cellulosic (eg 6010), where there is almost no way of making the hydrogen level higher, really forget about "low hydrogen" with 7018. Now, that wasn't your question... I think 7018's run a bit cleaner when dried to "low hydrogen" level. Even a hot quiver (not a rod oven) will often leave a pool of water on the floor under its door if you put in 7018's from an open packet and leave it for a few hours. So that's a lot of water out. I "hot quiver" rods in an open workshop and put into most moisture resistant container I can just because I think the arc is cleaner and the weld nicer. If you are doing a lot of welding, having a clean transparent smooth arc is nice and effort saving - get into a happy "groove" with everything running consistently. Consistent arc and easy welding will make the weld better, just by reason of ergonomics (how easy it is on the welder). A pleasing weld where the process does the work for you is going to give a better result, by reason that every weld is going to be as good as the "ideal" weld. By the way - "Basics" / 7018's etc. shield with the CO2 from the limestone (CaCO3) dissociating in the arc - giving also CaO as a highly scavenging flux. There isn't much CO2 produced, so you must be able to run with a short arc moving very smoothly - no fast manipulations / weaves / whipping-actions, etc. You mustn't dry any other rods than Basics (eg. 7018's), as they rely on the moisture / steam / hydrogen to shield. Losing shield is every problem, whereas the hydrogen shield is nothing of a problem. Regards, Rich
I knew I could count on you for a solution ... I'm a lousy stick weldor , my beads look like gobs of pigeon crap . But shit sticks together , so I'll keep on keepin' on . I'm not doing anything man-rated , and I'm careful to stay out of the likely impact zone if something fails . It appears that the recent modifications (which included stick welding with 7018 - vertical up) to my firewood handling system has made me at least twice as productive as compared to me actually lifting bigass chunks of log . Snag
==================== I needed a lot of expert advice and practice at Voc-Tech night classes before my 7018 beads looked good and more importantly withstood being bent double.
My present welding problem is a dime-sized rust hole in the Honda's rear fender lip, where the inner wheel well leaves no clearance for hammer and dolly adjustment. In 2010 I welded a flush patch, held in place with magnets, in the same area and made something of a mess because the thin steel melted through very easily. I chipped off the Bondo because the paint over it had cracked and found a still sound unrusted weld. In 2017 I welded the other side with a patch overlapped on the inside, which solved the melt-through issue but left a depression. Then I realized that the cause of the rust was an open seam between the inner and outer fenders, which I covered by gluing on stainless heat treating foil. This time I fitted a flush patch over a larger backing plate. So far one body shop quoted $100 to just weld it in.
I plan to seal the inner fenders and seams with Flex Tape which sticks like a barnacle. Has anyone else tried it?
I originally bought it to temporarily seal damage on a friend's truck without destroying the evidence. Clear Gorilla tape works well for that too, but doesn't conform to 3D curves and the adhesive doesn't peel off cleanly after a summer in the sun. The only problem with the Flex Tape was removing it afterwards. Then I tried it on boot soles that had worn thin and leaky. It held up for many months of outdoor work but was too slippery on snow.
Jim is all over it. Rod can be dried a couple times, but if redries to many times the flux falls off or angels loose their wings or pixies sprout warts warts so big it looks like the wart has grown a pixie...
The big boy have fancy rod drying ovens and heated rod storage and magical leprechauns that touch their rods with drying wands, but I just toss a few sticks at a time in the same toaster oven I use for powder coating small parts. I always have look up suggestions for temp and time.
I don't know how thin you are dealing with, but I've had fair luck with things like welding in the hole left in a pickup truck bed from a goose neck hitch by stacking beads with ordinary gasless flux core, then grinding it flat.
I just hold the trigger long enough for the metal to start to flow then let off. I move the stinger about half a bead diameter, wait for the red to almost fade, and shoot it again.
I know that sounds terrible, but I learned it using even more terrible welding machines. They say starts and stops are where most of your problems are. A weld like that is all starts and stops. After I grind it flat I just fill in any spots that look opened back up and grind it flat again.
I patched such a hole in the bed of my current truck back in 2007. I haven't managed to kick it out yet.
For really thin stuff like patching holes in muffler skins I learned to do it with an O/A torch and clothes hangers. You really can't grind those flat and smooth though. The mufflers skins are just to thin to take it.
I don't know how thin you are dealing with, but I've had fair luck with things like welding in the hole left in a pickup truck bed from a goose neck hitch by stacking beads with ordinary gasless flux core, then grinding it flat.
I just hold the trigger long enough for the metal to start to flow then let off. I move the stinger about half a bead diameter, wait for the red to almost fade, and shoot it again.
I know that sounds terrible, but I learned it using even more terrible welding machines. They say starts and stops are where most of your problems are. A weld like that is all starts and stops. After I grind it flat I just fill in any spots that look opened back up and grind it flat again.
I patched such a hole in the bed of my current truck back in 2007. I haven't managed to kick it out yet.
For really thin stuff like patching holes in muffler skins I learned to do it with an O/A torch and clothes hangers. You really can't grind those flat and smooth though. The mufflers skins are just to thin to take it.
==================================
I don't have any accessible unpainted, unrusted steel on the Honda to measure, but it feels about like 26 gauge, or maybe 0.5mm. I can neatly weld no-Bondo flush patches into the thicker steel of my Ford with a little practice.
I MIG welded rust-throughs in the other fender of the Honda to a thicker backing patch with less trouble, nearly an inch at a time.
When one sheet steel leg on this office chair broke I practiced fillets and gap-filling with O/A on it. I haven't used O/A on the car because the blackened zone is about 2" across and the inner side of the rear fender is mostly inaccessible to spray with rust inhibitor. Repair panels for that rust-prone area appear to have been discontinued, or all sold out.
The local muffler shop told me their machines couldn't do the job because they were set up for the thicker steel of mufflers.
I don't know how thin you are dealing with, but I've had fair luck with things like welding in the hole left in a pickup truck bed from a goose neck hitch by stacking beads with ordinary gasless flux core, then grinding it flat.
==============================
Another body shop quoted $125. Straight CO2 and 0.023" wire did the job, well enough for a 20 year old Honda. How should I spend the money I saved?
The custom shops I visited were restoring some beautiful old classic cars, at the cost of "Whatever it takes". Mine are just old, and valuable only to me.
One shop owner was rebuilding a 1935? radiator grille. He had run the punch press that made the originals and told me about the operation.
My new 5 lb package of 7018AC arrived yesterday , it's going to stay in the factory wrapper until the last dozen or so I had on hand are gone . Might be a few more weeks before I can lay that old stock on the wood stove . We're getting overnight lows in the 60's now but daytime highs are still in the mid 80's . I also have some 6011 and 6013 on hand , I can use that for whatever I need to weld that's too thick for the little MIG or outside where the TIG doesn't do so well .
My new 5 lb package of 7018AC arrived yesterday , it's going to stay in the factory wrapper until the last dozen or so I had on hand are gone . Might be a few more weeks before I can lay that old stock on the wood stove . We're getting overnight lows in the 60's now but daytime highs are still in the mid 80's . I also have some 6011 and 6013 on hand , I can use that for whatever I need to weld that's too thick for the little MIG or outside where the TIG doesn't do so well .
Snag
================================================= I learned 7018 because it's the 'status' professional rod, but otherwise I really like 7014.
"Snag" wrote in message news:rjmfgg$3pv$ snipped-for-privacy@dont-email.me...
My new 5 lb package of 7018AC arrived yesterday , it's going to stay in the factory wrapper until the last dozen or so I had on hand are gone . Might be a few more weeks before I can lay that old stock on the wood stove . We're getting overnight lows in the 60's now but daytime highs are still in the mid 80's . I also have some 6011 and 6013 on hand , I can use that for whatever I need to weld that's too thick for the little MIG or outside where the TIG doesn't do so well . Snag ====================================================== The IR temperature of the top of my wood stove runs 500F ~ 650F but things placed on it don't get quite that hot. Pure lead melts at 621.5F.
The temperature readout in the kitchen tells me when to add wood or reduce the air intake, and if I don't pay attention to it the stove's temperature fluctuates considerably depending on firewood split size and water content, air intake opening and outdoor temperature, which affects draft suction.
My wood stove is a copy of the old Jotul 118, clean-burning and efficient after I refitted and gasketed the joints, but fussy. I ran extension wire up for four thermocouples though only two are necessary, one for the body of the stove and the other for a probe in food simmering on it. The others were to datalog chimney and outdoor temperature while I was learning how to make the stove burn smoke-free, which with US hardwood is NOT the "cigarette burn" Jotul suggests. Temperatures weren't enough, there's also a night vision camera showing the chimney top.
It's a demanding beast only its mother (or a tinkerer) could love. However it anneals and hardens steel and heats through NH winters on usually less than 2 cords per year, while other similar houses use 5.
Interesting stove ..., I like ours , it's a King Circulater , it's controlled by an adjustable bimetallic spring hooked to an inlet baffle . It's very user friendly and not finicky at all ... I've never tried hardening steel in it , but I have annealed a few pieces . Your temp comments reminded me to get a stovepipe thermometer ordered , I think from the creosote buildup that I've been burning too cool . It's really
here though .
Interesting stove ..., I like ours , it's a King Circulater ,
===================================
Can you remove the louvered top and place the rods directly on the firebox?
Mine directs any smoke from the rear of the fire to the front where it mixes with separate preheated 'secondary' air and burns as it travels to the rear again under the top lid, so the front part of that lid is the hottest external part of the stove, and the only one that can reach 600F.
You must have the newer model of that stove . This one has no provision for secondary combustion . The top louver does come off , the top of the firebox is hottest just above the rear outlet . I have considered getting something newer and more efficient ... most likely secondary burn rather than catalytic . Those catalytic reactors are pricey and as I understand it they don't like low fires - which describes about half or more of our burn time . Last year we burned about 3 1/2 cords to heat
1500 sf . We were usually warmer than I really wanted , but there are 2 of us and she likes it a little warmer .
You must have the newer model of that stove . This one has no provision for secondary combustion . The top louver does come off , the top of the firebox is hottest just above the rear outlet . I have considered getting something newer and more efficient ... most likely secondary burn rather than catalytic . Those catalytic reactors are pricey and as I understand it they don't like low fires - which describes about half or more of our burn time . Last year we burned about 3 1/2 cords to heat
1500 sf . We were usually warmer than I really wanted , but there are 2 of us and she likes it a little warmer . Snag======================= My mother left the thermostat at 60F so I'm used to it. Norse ancestry has its advantages.
Mine's a Taiwanese ripoff of the 1970's model with the round air control and no internal tubing, just the baffle that directs smoke forward. I wouldn't desecrate a real Jotul 118 by carving a window opening in the name on the door to observe the fire. Machining the copy's cast iron showed that it was of decent quality and came off as shiny chips rather than powder, unlike other Asian CI I've cut which may have been relics of backyard iron smelting during the Great Leap Forward. I also ground the corner joint tenons for a closer fit, filed off the casting flash in the air intake and increased preheated secondary air flow, mainly through a 1/8" pipe nipple for the draft gauge. As with O/A the color of the flame helps set the mixture.
Wood stoves can be a dumping ground for high phosphorus iron that flows well into molds but lacks strength. The worst offender I own is an early 80's Duracraft drill press.
The stove can consider me as fussy as I've called it, since I ask it to hold
180C ~ 200C for an hour after feeding it without its exhaust showing any visible smoke or stinging my eyes, evidence of complete combustion. If I wasn't watching so closely it would seem fine unless fed damp wood that it can't handle as well as stoves with more air flow and chimney dampers.I haven't found a relation between a temperature measurement and the proper air opening (2.5-6mm) that fits all conditions. Pushing the control closed as the stove heats but not pulling it open on cooling comes closest. The hot door isn't a good place to mount an electrical actuator.
PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.