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Post by What It Was on Mar 10, 2006 10:22:58 GMT -5
All you true welders out there correct me if I'm wrong...
If You're welding a thick piece of metal thicker than what the welder is recommended for (As long as it isn't over kill on the thickness) try heating the metal up with a torch before you weld on it... This will help The "Lower Amp" welders to penetrate a little better... The Amps are what heats-up the metal and helps it to penetrate, In short... Thick Metals+Small Amp Welders+Heat Before Welding = Deeper Penetration. So heat it up before you start welding. For Stick Welders... Keep the rods heated as-well. (Hot enough to where you need a leather glove or something to pick them up... This is also a good way to keep your rods dry!).
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Post by PaulC on Mar 10, 2006 11:16:56 GMT -5
First bevel the metal. Then do muliply passes. Do a root pass, deslag, do a second pass, deslag and repeat untill desired thickness.
Preheating is for high strength steels and different types of steel (cast to mild).
PaulC
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Post by What It Was on Mar 10, 2006 11:30:12 GMT -5
Right, Bevel if you can... Normally I'll "Bridge" the welds 1st pass is centered... 2nd&3rd passes along the side and partially on 1st bead and 4th to "Bridge" the two outers. The reason I brought this topic up was I just came from the Machine Shop And I was watching this guy torch some plate steel (Carbon 3/8") and then he'd weld on it... I know on the boat we did this also but never really thought anything about it.. I asked the guy what are the benefits of heating the metal and he actually showed me the difference of welding on cold and heated metal... this was done on 1/4" plate steel... I was watching closely making sure his lead angle was the same so after he finished he cut the two pieces of metal and you could see that it penetrated almost a 1/16" deeper... Not exactly but close enough for the eye... So, now I feel more than comfortable with welding on my frame with my Lincoln Weld Pak 100.
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Post by CORE 4WD on Mar 10, 2006 21:18:54 GMT -5
What size rod are you using with the Weldpak? I would think it would handle 3/32 which is pretty much all I use for 1/8" on up to 1/4", although at 1/4" I'm usually using a "weave" pattern rather than just laying a straight bead. Your frame is probably around 1/8" wall?
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Post by What It Was on Mar 11, 2006 1:18:55 GMT -5
I have a Lincoln 100 Pack Mig and 2 Sticks... One big Lincoln and the other Is a small Lunch box 220 and can handle 3/32 rods. When I use the stick I do 1/4 to half moon patterns sometimes small circles... depending on thickness and type of weld wanted. I don't believe in "dragging" When I was taught how to Weld they guy said never to drag... "Unless you want to be like the rest of these lazy welders". He then went on to mention the benefits of "weaving and small circles)... After I got that down he taught me tig. This dude, his name was Wachtel Could Tig better than anybody I have seen... You want to talk about "laying dimes"... He was the man!!!
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Post by PaulC on Mar 11, 2006 3:25:55 GMT -5
Like Dave said there are several different ways to lay down welds will an arc. Laying down rows (small circles) is usually for right angle and over head. Weaving after a root pass is for vertical and flat. I'd like to see Dave do a weave overhead while dodging the hot melten metal and slap with an arc J/K.
If you worried penetration use a smaller rod and multiple passes, if the bigger rod isn't penetrating as much as needed.
PaulC
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Post by What It Was on Mar 11, 2006 13:47:05 GMT -5
No worries about penetration, hahaha (I better start phrasing my words a little better). ;D I bought a Stick welder brand new off of ebay 220v 100amp for $26 + shipping & Handling... I just tried it and I have no doubts about penetration... I'm sure that it'll penetrate deep if the metal is already heated... As for the beads.. I always do 1/4 or 1/2 moons or circles no matter if it's a root pass vert weld etc.. If I start with a Circle I stay with it... etc etc. I never change the pattern of the weld... I don't like dragging my rods... it'll work but I feel more comfortable with weaving, circles etc..
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Post by CORE 4WD on Mar 12, 2006 20:04:53 GMT -5
I never "drag" in the literal sense, I always pull just above material depending how hot I want the arc (you can fine-tune by going closer or further away). Like PaulC mentioned, there is a motion for each type of joint fitment but you seem to already have that down. Yea PaulC, overhead arc SUX!
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Post by What It Was on Mar 12, 2006 20:19:12 GMT -5
I agree... Overhead welds are the worst.. especially when it makes it's way down under the leather and into the shirt and down to the underwear... Or when it sits next to the collar-bone and the neck area... (That little void area!!!).
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Post by N2Rocks on Mar 12, 2006 20:39:53 GMT -5
I have an AC/DC arc and a MIG that welds with or without gas. I like the MIG for light duty welding or tacks. I prefer the arc welder for anything structural or requiring high strength. I feel arc welding provides greater penetration. Along with the penetration, the welder must be able to maintain a puddle of molten weld. The purpose of using a circular or sweeping pattern is to agitate the puddle. By agitating the molten puddle, impurities are able to rise to the top of the puddle and allows the weld to flow into the area burned away by the arc. A simple AC arc welder is good projects. Preheating my help maintain a good puddle, but if it's required, I'd use a bigger welder. Consider it like a hammer, sometimes a smaller hammer won't work, no matter how many times you try to hit it!
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Post by CORE 4WD on Mar 12, 2006 21:43:26 GMT -5
I find the stick is easier to get a good angle on 90 degree joints and tight spots as well, no nozzle getting in the way and it's easier to see the puddle...
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Post by Chuck on Mar 13, 2006 9:48:37 GMT -5
I find the stick is easier to get a good angle on 90 degree joints and tight spots as well, no nozzle getting in the way and it's easier to see the puddle... No argument there, getting into tight corners with a MIG nozzle is a royal PITA at times. I'm actually running my contact tips slightly long right now, with about 1/16" of the tip protruding from the nozzle -- helps get into corners and keep stickout down to a reasonable length. I did get a series of really good pics yesterday when I was doing a full penetration beveled butt weld on 1/4" plate, since I remembered this topic had come up. My little Miller MIG machine is officially rated at 135A, but 100A is about all I usually see with the 0.030 wire I run, based on a friend watching an inductive ammeter for me. With a MIG box this size, full penetration takes about a 45* bevel with three passes, followed, by a single pass down the backside. I'll post the pics when I get a chance, I forgot to download them off my friend's camera so it may be next weekend before I get a chance. Oops.
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Post by What It Was on Mar 13, 2006 11:53:23 GMT -5
Awesome... I'll be looking for them. I was told today by a welder that you can normally check you penetration by the discoloration of the metal around the bead (on either side).. He said it's not the most accurate way but it'll put you in the ball park. I tried it a little while ago On some 3/8" Stainless plate... And it wasn't exactly like he described but... for me it was close enough.. (I have to stop wasting my materials).
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Post by Chuck on Mar 13, 2006 17:36:24 GMT -5
Hey, "wasting" material can be a good thing ... if I'm going to try something, I'd rather try it on a piece of scrap I picked up at $0.30 a pound than a nice, shiny new piece of A500B square tube at $0.80 per! ;D
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Post by What It Was on Mar 13, 2006 18:42:55 GMT -5
True... Very good point!!!
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