Original Posted By: Jim Ash
Subject: Pietenpol-List: ie: Torch questionHi Everyone,I thought I would put my 2 cents in about torches. If you can afford it a TIG set-up is wonderful. For those unfamiliar, TIG is Tungston Inert Gas, which amounts to an electric arc welder with Argon flowing around the weld atall times to keep out any oxygen. It is very fast and easy once you learn how,and if you have it available you will never go back to gas welding. The results are fantastic and fast, as you do not have to pre-heat. I also used mine to weld my aluminum gas tank. This took a little more practice but I finally got it. Compared to gas welding, the ongoing cost might even be cheaper,as you have to buy filler rod and only one gas instead of two. I attended one of the weekend SportAir TIG Welding workshops offered by EAA down in the Atlanta area. This was very helpful and I would recommend it highly. Dan HelsperPoplar Grove, IL.________________________________________________________________________________Date: Tue, 26 Sep 2006 12:47:05 -0400 (GMT-04:00)
Pietenpol-List: ie: Torch question
RE: Pietenpol-List: ie: Torch question
Original Posted By: owner-pietenpol-list-server(at)matronics.com
Hello! From what I've read and heard from other aircraft builders.... Likeon a steel tube Fuselage or landing gear...... you can "tack" weld ittogether with Tig, but should always gas weld it.For brackets and such the "Tig" is fine.Dave-----Original Message-----
Hello! From what I've read and heard from other aircraft builders.... Likeon a steel tube Fuselage or landing gear...... you can "tack" weld ittogether with Tig, but should always gas weld it.For brackets and such the "Tig" is fine.Dave-----Original Message-----
Re: Pietenpol-List: ie: Torch question
Original Posted By: "Dave Abramson"
Dave,Not sure you still have to exclusively gas weld. If you use argon blanket of inert gas around the wire feed weld you avoid "burning" out the carbon in the 4130 steel, thus making it brittle. You should go back at all weld junctions and use a non-oxidizing flame (more gas than oxygen) heating up the weld to relieve any stresses, "normalizing the weld". But fact is, on many 4130 parts, it's actually easier to gas weld due to the complex nature of the rounded shapes. So, on my Piete, I tacked up the part using wirefeed and argon blanket, then test fitted to insure the parts match up, then gas welded (non-oxidizing flame).Gordon----- Original Message -----
Dave,Not sure you still have to exclusively gas weld. If you use argon blanket of inert gas around the wire feed weld you avoid "burning" out the carbon in the 4130 steel, thus making it brittle. You should go back at all weld junctions and use a non-oxidizing flame (more gas than oxygen) heating up the weld to relieve any stresses, "normalizing the weld". But fact is, on many 4130 parts, it's actually easier to gas weld due to the complex nature of the rounded shapes. So, on my Piete, I tacked up the part using wirefeed and argon blanket, then test fitted to insure the parts match up, then gas welded (non-oxidizing flame).Gordon----- Original Message -----
>> Pietenpol-List: ie: Torch question
Original Posted By: Jim Ash
Re: Pietenpol-List: ie: Torch question
Original Posted By: Jim Ash
Subject: Re: Pietenpol-List: ie: Torch questionIn a message dated 9/26/2006 2:48:23 PM Central Standard Time, gbowen(at)ptialaska.net writes:I tacked up the part using wirefeed and argon blanket, then test fitted to insure the parts match up, then gas welded (non-oxidizing flame).That's how I did my Tailwind fuselage. I've seen firsthand, how the heat affected zone of TIG welds crack.Chuck G.NX770CG________________________________________________________________________________Date: Tue, 26 Sep 2006 18:52:47 -0400 (GMT-04:00)
Subject: Re: Pietenpol-List: ie: Torch questionIn a message dated 9/26/2006 2:48:23 PM Central Standard Time, gbowen(at)ptialaska.net writes:I tacked up the part using wirefeed and argon blanket, then test fitted to insure the parts match up, then gas welded (non-oxidizing flame).That's how I did my Tailwind fuselage. I've seen firsthand, how the heat affected zone of TIG welds crack.Chuck G.NX770CG________________________________________________________________________________Date: Tue, 26 Sep 2006 18:52:47 -0400 (GMT-04:00)
Re: Pietenpol-List: ie: Torch question
Original Posted By: "Jim Ash"
Great input Jim,Back when Oshcash was more for the homebuilders needs, the workshop tents dedicated to welding was an excellent place to learn both old and new techniques.Gordon----- Original Message -----
Great input Jim,Back when Oshcash was more for the homebuilders needs, the workshop tents dedicated to welding was an excellent place to learn both old and new techniques.Gordon----- Original Message -----
Re: Pietenpol-List: ie: Torch question
Original Posted By: "Gordon Bowen"
Subject: Re: Pietenpol-List: ie: Torch questionThis is a direct quote from a "frequently asked questions" sheet published by Lincoln Electric on the subject of welding 4130. Q. Do I need to preheat?A. Thin wall tubing (<0.120" wall) applications do not typically require the normal 300F to 400F pre-heat to obtain acceptable results. However, tubing should be at room temperature (70F) or above before welding.Q. Do I need to heat treat (stress relieve) 4130 after welding?A. Thin wall tubing normally does not require stress relief. For parts thicker than .120" stress-relieving is recommended and 1,100F is the optimum temperature for tubing applications. An Oxy/Acetylene torch with neutral flame can be used. It should be oscillated to avoid hot spots.Hope this can clarify some of the misinformed opinions. Is there anywhere on a Piet where it calls for thicker than .120" in a welding application? Dan HelsperPoplar Grove, IL________________________________________________________________________________
Subject: Re: Pietenpol-List: ie: Torch questionThis is a direct quote from a "frequently asked questions" sheet published by Lincoln Electric on the subject of welding 4130. Q. Do I need to preheat?A. Thin wall tubing (<0.120" wall) applications do not typically require the normal 300F to 400F pre-heat to obtain acceptable results. However, tubing should be at room temperature (70F) or above before welding.Q. Do I need to heat treat (stress relieve) 4130 after welding?A. Thin wall tubing normally does not require stress relief. For parts thicker than .120" stress-relieving is recommended and 1,100F is the optimum temperature for tubing applications. An Oxy/Acetylene torch with neutral flame can be used. It should be oscillated to avoid hot spots.Hope this can clarify some of the misinformed opinions. Is there anywhere on a Piet where it calls for thicker than .120" in a welding application? Dan HelsperPoplar Grove, IL________________________________________________________________________________
Re: Pietenpol-List: ie: Torch question
Original Posted By: HelsperSew(at)aol.com
Couple of practical points:1) 90% of all 4130 tube in all homebuilts, including the Piete, I've worked with is 0.035 or thinner.2) Lots of folks do their welding of parts in unheated hangers or garages, many times much less than 70F steel feed stock. When the steel is colder, it pops, crackles and leaves lots of little pinholes in the weld.3) think, from a experience point of view, you gotta be kinda good as a welder to make good consistant wirefeed welds. It's easier to tack weld parts and then gas weld because most homebuilders who do something else other than weld for a living, need lots and lots of practice. 4) The normalizing of clusters of welded tube takes the unwanted kinks out of the point of weld, the longerons will buckle slightly every where there's a thick cluster. If you leave them in, the fuselage wants to buckle up at these thick clusters, so it can't hurt to normalize even if not required by the folks at Lincoln.5) Lastly, if you want a better wirefeed welder, buy a Miller not a Lincoln. Ck out the weight and size of their individual transformers to see the diff in quality and ability to not overheat and shutdown during an extended welding period. I've owned both names and really like the Miller much better machine, but Lincoln is cheaper to buy.Gordon ----- Original Message -----
Couple of practical points:1) 90% of all 4130 tube in all homebuilts, including the Piete, I've worked with is 0.035 or thinner.2) Lots of folks do their welding of parts in unheated hangers or garages, many times much less than 70F steel feed stock. When the steel is colder, it pops, crackles and leaves lots of little pinholes in the weld.3) think, from a experience point of view, you gotta be kinda good as a welder to make good consistant wirefeed welds. It's easier to tack weld parts and then gas weld because most homebuilders who do something else other than weld for a living, need lots and lots of practice. 4) The normalizing of clusters of welded tube takes the unwanted kinks out of the point of weld, the longerons will buckle slightly every where there's a thick cluster. If you leave them in, the fuselage wants to buckle up at these thick clusters, so it can't hurt to normalize even if not required by the folks at Lincoln.5) Lastly, if you want a better wirefeed welder, buy a Miller not a Lincoln. Ck out the weight and size of their individual transformers to see the diff in quality and ability to not overheat and shutdown during an extended welding period. I've owned both names and really like the Miller much better machine, but Lincoln is cheaper to buy.Gordon ----- Original Message -----
Re: Pietenpol-List: ie: Torch question
Original Posted By: Clif Dawson