Brodhead Pietenpol Association

Original Posted By: walter evans
Subject: Pietenpol-List: Re: grain in 4130 sheetsWalt, I have not heard of this. As a newbie to homebuilding I have readall of Tony B's books and most of the EAA stuff.I can remember reading that grain doesn't matter in flat pieces butshould be perpendicular to any bends whenever possible.Also haven't seen anything before about normalizing fittings aftergrinding. Some of my fittings did get those little brownishspots on the edges where I got em a little hot. Can you give a littlemore info for reference? -----Original Message-----

Original Posted By: walter evans
Subject: Re: grain in 4130 sheets Walt, I have not heard of this. As a newbie to homebuilding I haveread all of Tony B's books and most of the EAA stuff. I can remember reading that grain doesn't matter in flat pieces butshould be perpendicular to any bends whenever possible. Also haven't seen anything before about normalizing fittings aftergrinding. Some of my fittings did get those little brownish spots on the edges where I got em a little hot. Can you give alittle more info for reference? -----Original Message-----

Original Posted By: Mike Cunningham
Subject: Fw: grain in 4130 sheets Mike, I've always been impressed with the experience of my AP. He'san old guy who's been doing this for years. His "rule" is to make thebracket length with the grain. I guess it would be like making a 2x4with the grain going across the board. Wouldn't be very strong. Andalways bend across the grain. Also any "quick" heat on 4130 causesbrittleness, which could come from a grinder,(torch cutting is a no-no)if you ever tried to file 4130 at a torch cut, you'll see its harderthan the file. I just figure if I'm going to make the bracket, I'll make it likethe pros. walt PS If you ever saw the picture on one of the Pietenpol sites ,taken at Brodhead, showing a guy running an engine on a stand. This AP is the guy that took that engine, with a single throwcrankshaft, and made a double throw crank (from a block of steel) rebuilt it , and you see it run. He 's building another crank now. -----Original Message-----

Original Posted By: dannymac
Subject: grain in 4130 sheets Make sure that when you make brackets and fittings, that you cutthem from sheet "with the grain" of the sheet. The grain runs with the printing on the sheet. And any fitting that you cut out with a grinder,where the wheel cancause hot spots, make sure that you normalize the piece. Unless it willbe welded, which will take care of that anyway. walt________________________________________________________________________________

Original Posted By: Hatz630(at)aol.com
Subject: grain in 4130 sheets Make sure that when you make brackets and fittings, that you cutthem from sheet "with the grain" of the sheet. The grain runs with the printing on the sheet. And any fitting that you cut out with a grinder,where the wheel cancause hot spots, make sure that you normalize the piece. Unless it willbe welded, which will take care of that anyway. walt________________________________________________________________________________

Original Posted By: Michael D Cuy
Subject: grain in 4130 sheets Make sure that when you make brackets and fittings, that you cutthem from sheet "with the grain" of the sheet. The grain runs with the printing on the sheet. And any fitting that you cut out with a grinder,where the wheelcan cause hot spots, make sure that you normalize the piece. Unless itwill be welded, which will take care of that anyway. walt________________________________________________________________________________

Original Posted By: "Sayre, William G"
Make sure that when you make brackets and fittings, that you cut themfrom sheet "with the grain" of the sheet.The grain runs with the printing on the sheet.And any fitting that you cut out with a grinder,where the wheel cancause hot spots, make sure that you normalize the piece. Unless it willbe welded, which will take care of that anyway.waltMake sure that when you makebrackets andfittings, that you cut them from sheet with the grain of thesheet.The grain runs with the printing onthesheet.And any fitting that you cut outwith agrinder,where the wheel can cause hot spots, make sure that younormalize thepiece. Unless it will be welded, which will take care of thatanyway.walt________________________________________________________________________________

Original Posted By: walter evans
Walt, I have not heard of this. As a newbie to homebuilding I have readall of Tony B's books and most of the EAA stuff.I can remember reading that grain doesn't matter in flat pieces butshould be perpendicular to any bends whenever possible.Also haven't seen anything before about normalizing fittings aftergrinding. Some of my fittings did get those little brownishspots on the edges where I got em a little hot. Can you give a littlemore info for reference?-----Original Message-----

Original Posted By: Mike Cunningham
Mike, I've always been impressed with the experience of my AP. He's anold guy who's been doing this for years. His "rule" is to make thebracket length with the grain. I guess it would be like making a 2x4with the grain going across the board. Wouldn't be very strong. Andalways bend across the grain. Also any "quick" heat on 4130 causesbrittleness, which could come from a grinder,(torch cutting is a no-no)if you ever tried to file 4130 at a torch cut, you'll see its harderthan the file.I just figure if I'm going to make the bracket, I'll make it like thepros.waltPS If you ever saw the picture on one of the Pietenpol sites , taken atBrodhead, showing a guy running an engine on a stand.This AP is the guy that took that engine, with a single throwcrankshaft, and made a double throw crank (from a block of steel)rebuilt it , and you see it run. He 's building another crank now.-----Original Message-----

Original Posted By: oil can
Subject: Pietenpol-List: Re: Fw: grain in 4130 sheets>I had a structural engineer from Boeing tell me that with flat steel the>grain direction>does not really matter. If it is aluminum it is a different story. The>grain direction does>matter.>> Ron>>________________________________________________________________________________

Original Posted By: Earl Myers
I had a structural engineer from Boeing tell me that with flat steel the grain directiondoes not really matter. If it is aluminum it is a different story. The grain direction doesmatter. Ron________________________________________________________________________________

Original Posted By: PTNPOL(at)aol.com
Sir; Engineering matters aside, one of the first things the FAA guys look foraround here is just that......."...did ya bend with the grain or agin'it...?"Earl Myers-----Original Message-----

Original Posted By:>> walter evans
Subject: Pietenpol-List: Re: grain in 4130 sheets>I myself have no refrence on what happens to steel that has been ground too>hot, but if any one would like to test the theroy, just take two pieces of>steel, grind one till it turns blue, and then try to cut both with a file.>>The blue one will have been hardened by heat, and air. A hrdened part it>brittle, and subjuct to crackes.>>>>From: Mike Cunningham >>Reply-To: Pietenpol Discussion >>To: Pietenpol Discussion >>Subject: Re: grain in 4130 sheets>>Date: Fri, 18 Jun 1999 13:16:04 -0500>>>>Walt, I have not heard of this. As a newbie to homebuilding I have readall>>of Tony B's books and most of the EAA stuff.>>I can remember reading that grain doesn't matter in flat pieces but should>>be perpendicular to any bends whenever possible.>>Also haven't seen anything before about normalizing fittings after>>grinding. Some of my fittings did get those little brownish>>spots on the edges where I got em a little hot. Can you give a little more>>info for reference?>>-----Original Message-----

Original Posted By:> walter evans
I myself have no refrence on what happens to steel that has been ground too hot, but if any one would like to test the theroy, just take two pieces of steel, grind one till it turns blue, and then try to cut both with a file.The blue one will have been hardened by heat, and air. A hrdened part it brittle, and subjuct to crackes.>From: Mike Cunningham >Reply-To: Pietenpol Discussion >To: Pietenpol Discussion >Subject: Re: grain in 4130 sheets>Date: Fri, 18 Jun 1999 13:16:04 -0500>>Walt, I have not heard of this. As a newbie to homebuilding I have read all >of Tony B's books and most of the EAA stuff.>I can remember reading that grain doesn't matter in flat pieces but should >be perpendicular to any bends whenever possible.>Also haven't seen anything before about normalizing fittings after >grinding. Some of my fittings did get those little brownish>spots on the edges where I got em a little hot. Can you give a little more >info for reference?>-----Original Message-----

Original Posted By: Earl Myers
Subject: Pietenpol-List: Re: grain in 4130 sheets>Dear Builders,>> Do I understand correctly that bar-stock has the grain running>lengthways and should not concern myself with grain when cutting>fittings from such? Also, if I purchase sheet-goods and shear 1"or 5/8">strips from them, the strips should be running the same direction as the>printing? Is there ever a visible grain. I ask in earnest.>>Dannymac>>walter evans wrote:>>>> Make sure that when you make brackets and fittings, that you cut them>> from sheet "with the grain" of the sheet.>> The grain runs with the printing on the sheet.>> And any fitting that you cut out with a grinder,where the wheel can>> cause hot spots, make sure that you normalize the piece. Unless it>> will be welded, which will take care of that anyway.>> walt>>________________________________________________________________________________

Original Posted By:-----Original Message-----
Subject: Pietenpol-List: Re: grain in 4130 sheets> Back to 4130. When you heat steel past its melting point thephysical>alignment of molecules changes back to the gelatinous, unoriented mixof>chromium, iron, carbon, nickel, etc.. and loses the strength gained by>aligning the particles. The bluing is several things: the carbon isbeing>burned out, the iron is oxidizing, and the other annealing members like>chromium are probably combining with oxygen and changing colors. Torchcut>4130 is harder because its molecules are boxier(like maple) and itsmakeup>is more resistant to filing which is actually a type of shearingaction.> If you were to cut (with the lowest temperature possible) beyondthe>bluing region on your work piece, the normal strength andcharacteristics>would be there.> Well gang, I know this was bit long but I hope it helps.Thanks Brian, for the description of how steels are affected byheat.I may however disagree with your statement, Whenyouheat steel past its melting point, temperatures well belowthemelting point become critical when working with steel. Steels generally, are heat treatable they willhardenand become more brittle when cooled quickly from their criticaltemperatures.Still below the melting point. Interestingly they loose theability tobe attracted to a magnet at these elevated temperatures as the moleculesatthose temperatures are not in any particular alignment. They can be made softer and and more ductile by controlled heatingandcooling at temperatures well below their melting point. The reasonthat wepost heat and cool the welds slowly. (see tempering andannealing)The point is that we should take every effort to follow the steelmanufacturer's recommended practices when working with steelalloys.(BTW all steels are alloys and the differing ingredients,(41xxseries steels are alloyed with Chromium and Molybdenum), are what makethe steelsuitable for each application.)I would recommend that we as builders follow established buildingpractices. A trip to the library should turn up a few good referencetexts onthe steels and other metals used in our hobby. After all, the reasons we are allowed to build our ownaircraft (atleast in Canada) are recreation and education.John Mc

Original Posted By:>>> walter evans
Subject: Pietenpol-List: Re: grain in 4130 sheets> Any steel, especially 4130, will actually change physical properties>when heated beyond its melting point.>Flat stock of any shape (angles, sheet, rods, U's, etc, ) are drawn through>mandrels when in the hot, molten, gelatinous state. Right out of thefurnace>their molecular alignment is one right beside the other, sort of like rice>kernels just after you've drained the water, in a random, unoriented mix.>When you force the ingots of hot steel through specially shaped openings,>you do two things:1) you create a mechanically advantageous shape for your>structural needs of a material that has homogeneous strength and working>properties in longitudinal direction (with the grain), and slightly less>workability across the grain. 2) the rolling or drawing process actually>realigns the molecules in a linear pattern (one molecule beside another) so>that they resemble short strands of string glued together. Sidebar: thisthe>difference between cast iron and wrought iron - wrought means to hammerinto>long sinuous fibers.> A good analogy for us woodworkers is maple vs.. spruce: mother nature>has already "aligned" spruce fibers in a longitudinal high tension pattern,>which also bends nicely because the fibers microscopically slide past each>other but still maintain contact along the rest of their length.>Maple. on the other hand, is very angular in molecular makeup, boxy shaped,>and is great in compression and resistant to denting (tabletops), butreally>pales by comparison in tension because the wood fibre cells have so little>surface area end-to-end to connect to each other, and pop apart easily. Ash>is a good compromise of both compressive and tensile characteristics: it>bends, resists shearing, loads well in compression, has good tensile>strength. But alas, it's a bit heavy -a bummer for Piet builders.> Back to 4130. When you heat steel past its melting point the physical>alignment of molecules changes back to the gelatinous, unoriented mix of>chromium, iron, carbon, nickel, etc.. and loses the strength gained by>aligning the particles. The bluing is several things: the carbon is being>burned out, the iron is oxidizing, and the other annealing members like>chromium are probably combining with oxygen and changing colors. Torch cut>4130 is harder because its molecules are boxier(like maple) and its makeup>is more resistant to filing which is actually a type of shearing action.> If you were to cut (with the lowest temperature possible) beyond the>bluing region on your work piece, the normal strength and characteristics>would be there.> Well gang, I know this was bit long but I hope it helps.>---Original Message----->From: oil can >To: Pietenpol Discussion >Date: Sunday, June 20, 1999 1:24 AM>Subject: Re: grain in 4130 sheets>>>>I myself have no refrence on what happens to steel that has been groundtoo>>hot, but if any one would like to test the theroy, just take two piecesof>>steel, grind one till it turns blue, and then try to cut both with a file.>>>>The blue one will have been hardened by heat, and air. A hrdened part it>>brittle, and subjuct to crackes.>>>>>>>From: Mike Cunningham >>>Reply-To: Pietenpol Discussion >>>To: Pietenpol Discussion >>>Subject: Re: grain in 4130 sheets>>>Date: Fri, 18 Jun 1999 13:16:04 -0500>>>>>>Walt, I have not heard of this. As a newbie to homebuilding I have read>all>>>of Tony B's books and most of the EAA stuff.>>>I can remember reading that grain doesn't matter in flat pieces butshould>>>be perpendicular to any bends whenever possible.>>>Also haven't seen anything before about normalizing fittings after>>>grinding. Some of my fittings did get those little brownish>>>spots on the edges where I got em a little hot. Can you give a littlemore>>>info for reference?>>>-----Original Message-----

Original Posted By:>>> walter evans
Subject: Pietenpol-List: Re: grain in 4130 sheets> Any steel, especially 4130, will actually change physical properties>when heated beyond its melting point.>Flat stock of any shape (angles, sheet, rods, U's, etc, ) are drawn through>mandrels when in the hot, molten, gelatinous state. Right out of thefurnace>their molecular alignment is one right beside the other, sort of like rice>kernels just after you've drained the water, in a random, unoriented mix.>When you force the ingots of hot steel through specially shaped openings,>you do two things:1) you create a mechanically advantageous shape for your>structural needs of a material that has homogeneous strength and working>properties in longitudinal direction (with the grain), and slightly less>workability across the grain. 2) the rolling or drawing process actually>realigns the molecules in a linear pattern (one molecule beside another) so>that they resemble short strands of string glued together. Sidebar: thisthe>difference between cast iron and wrought iron - wrought means to hammerinto>long sinuous fibers.> A good analogy for us woodworkers is maple vs.. spruce: mother nature>has already "aligned" spruce fibers in a longitudinal high tension pattern,>which also bends nicely because the fibers microscopically slide past each>other but still maintain contact along the rest of their length.>Maple. on the other hand, is very angular in molecular makeup, boxy shaped,>and is great in compression and resistant to denting (tabletops), butreally>pales by comparison in tension because the wood fibre cells have so little>surface area end-to-end to connect to each other, and pop apart easily. Ash>is a good compromise of both compressive and tensile characteristics: it>bends, resists shearing, loads well in compression, has good tensile>strength. But alas, it's a bit heavy -a bummer for Piet builders.> Back to 4130. When you heat steel past its melting point the physical>alignment of molecules changes back to the gelatinous, unoriented mix of>chromium, iron, carbon, nickel, etc.. and loses the strength gained by>aligning the particles. The bluing is several things: the carbon is being>burned out, the iron is oxidizing, and the other annealing members like>chromium are probably combining with oxygen and changing colors. Torch cut>4130 is harder because its molecules are boxier(like maple) and its makeup>is more resistant to filing which is actually a type of shearing action.> If you were to cut (with the lowest temperature possible) beyond the>bluing region on your work piece, the normal strength and characteristics>would be there.> Well gang, I know this was bit long but I hope it helps.>---Original Message----->From: oil can >To: Pietenpol Discussion >Date: Sunday, June 20, 1999 1:24 AM>Subject: Re: grain in 4130 sheets>>>>I myself have no refrence on what happens to steel that has been groundtoo>>hot, but if any one would like to test the theroy, just take two piecesof>>steel, grind one till it turns blue, and then try to cut both with a file.>>>>The blue one will have been hardened by heat, and air. A hrdened part it>>brittle, and subjuct to crackes.>>>>>>>From: Mike Cunningham >>>Reply-To: Pietenpol Discussion >>>To: Pietenpol Discussion >>>Subject: Re: grain in 4130 sheets>>>Date: Fri, 18 Jun 1999 13:16:04 -0500>>>>>>Walt, I have not heard of this. As a newbie to homebuilding I have read>all>>>of Tony B's books and most of the EAA stuff.>>>I can remember reading that grain doesn't matter in flat pieces butshould>>>be perpendicular to any bends whenever possible.>>>Also haven't seen anything before about normalizing fittings after>>>grinding. Some of my fittings did get those little brownish>>>spots on the edges where I got em a little hot. Can you give a littlemore>>>info for reference?>>>-----Original Message-----

Original Posted By: oil can
Any steel, especially 4130, will actually change physical propertieswhen heated beyond its melting point.Flat stock of any shape (angles, sheet, rods, U's, etc, ) are drawn throughmandrels when in the hot, molten, gelatinous state. Right out of the furnacetheir molecular alignment is one right beside the other, sort of like ricekernels just after you've drained the water, in a random, unoriented mix.When you force the ingots of hot steel through specially shaped openings,you do two things:1) you create a mechanically advantageous shape for yourstructural needs of a material that has homogeneous strength and workingproperties in longitudinal direction (with the grain), and slightly lessworkability across the grain. 2) the rolling or drawing process actuallyrealigns the molecules in a linear pattern (one molecule beside another) sothat they resemble short strands of string glued together. Sidebar: this thedifference between cast iron and wrought iron - wrought means to hammer intolong sinuous fibers. A good analogy for us woodworkers is maple vs.. spruce: mother naturehas already "aligned" spruce fibers in a longitudinal high tension pattern,which also bends nicely because the fibers microscopically slide past eachother but still maintain contact along the rest of their length.Maple. on the other hand, is very angular in molecular makeup, boxy shaped,and is great in compression and resistant to denting (tabletops), but reallypales by comparison in tension because the wood fibre cells have so littlesurface area end-to-end to connect to each other, and pop apart easily. Ashis a good compromise of both compressive and tensile characteristics: itbends, resists shearing, loads well in compression, has good tensilestrength. But alas, it's a bit heavy -a bummer for Piet builders. Back to 4130. When you heat steel past its melting point the physicalalignment of molecules changes back to the gelatinous, unoriented mix ofchromium, iron, carbon, nickel, etc.. and loses the strength gained byaligning the particles. The bluing is several things: the carbon is beingburned out, the iron is oxidizing, and the other annealing members likechromium are probably combining with oxygen and changing colors. Torch cut4130 is harder because its molecules are boxier(like maple) and its makeupis more resistant to filing which is actually a type of shearing action. If you were to cut (with the lowest temperature possible) beyond thebluing region on your work piece, the normal strength and characteristicswould be there. Well gang, I know this was bit long but I hope it helps.---Original Message-----________________________________________________________________________________

Original Posted By: Brian K. Sanders
Brian, Excellent insight you gave us on the properties of grain in 4130 steel asit applies to our use. I, for one, didn't realize the importance of grainorientation when fabricating fittings for my Piet but I sure do now. Onceagain thanks for the info.-----Original Message-----

Original Posted By: Brian K. Sanders
Brian,WOW, thanks for the support. I made my fittings with the grain, but Ididn't know there was that much to it.All makes great sense. thankswalt-----Original Message-----

Original Posted By:> oil can
Brian, Thanks for such a concise and understandable explanation on metal grain. Ihave never grasped this before now. Have printed this for inclusion in myproject notebook. Just another great benefit from this group.Cheers,Warren"Brian K. Sanders" wrote:> Any steel, especially 4130, will actually change physical properties> when heated beyond its melting point.> Flat stock of any shape (angles, sheet, rods, U's, etc, ) are drawn through> mandrels when in the hot, molten, gelatinous state. Right out of the furnace> their molecular alignment is one right beside the other, sort of like rice> kernels just after you've drained the water, in a random, unoriented mix.> When you force the ingots of hot steel through specially shaped openings,> you do two things:1) you create a mechanically advantageous shape for your> structural needs of a material that has homogeneous strength and working> properties in longitudinal direction (with the grain), and slightly less> workability across the grain. 2) the rolling or drawing process actually> realigns the molecules in a linear pattern (one molecule beside another) so> that they resemble short strands of string glued together. Sidebar: this the> difference between cast iron and wrought iron - wrought means to hammer into> long sinuous fibers.> A good analogy for us woodworkers is maple vs.. spruce: mother nature> has already "aligned" spruce fibers in a longitudinal high tension pattern,> which also bends nicely because the fibers microscopically slide past each> other but still maintain contact along the rest of their length.> Maple. on the other hand, is very angular in molecular makeup, boxy shaped,> and is great in compression and resistant to denting (tabletops), but really> pales by comparison in tension because the wood fibre cells have so little> surface area end-to-end to connect to each other, and pop apart easily. Ash> is a good compromise of both compressive and tensile characteristics: it> bends, resists shearing, loads well in compression, has good tensile> strength. But alas, it's a bit heavy -a bummer for Piet builders.> Back to 4130. When you heat steel past its melting point the physical> alignment of molecules changes back to the gelatinous, unoriented mix of> chromium, iron, carbon, nickel, etc.. and loses the strength gained by> aligning the particles. The bluing is several things: the carbon is being> burned out, the iron is oxidizing, and the other annealing members like> chromium are probably combining with oxygen and changing colors. Torch cut> 4130 is harder because its molecules are boxier(like maple) and its makeup> is more resistant to filing which is actually a type of shearing action.> If you were to cut (with the lowest temperature possible) beyond the> bluing region on your work piece, the normal strength and characteristics> would be there.> Well gang, I know this was bit long but I hope it helps.> ---Original Message-----

Original Posted By: dannymac
Dear Builders, Do I understand correctly that bar-stock has the grain runninglengthways and should not concern myself with grain when cuttingfittings from such? Also, if I purchase sheet-goods and shear 1"or 5/8"strips from them, the strips should be running the same direction as theprinting? Is there ever a visible grain. I ask in earnest.Dannymacwalter evans wrote:> > Make sure that when you make brackets and fittings, that you cut them> from sheet "with the grain" of the sheet.> The grain runs with the printing on the sheet.> And any fitting that you cut out with a grinder,where the wheel can> cause hot spots, make sure that you normalize the piece. Unless it> will be welded, which will take care of that anyway.> walt________________________________________________________________________________

Original Posted By: Brian K. Sanders
Thanks Brian, for the description of how steels are affected by heat. I may however disagree with your statement, " When you heat steel pastits melting point", temperatures well below the melting point become"critical" when working with steel. Steels generally, are heat treatable they will harden and becomemore brittle when cooled quickly from their critical temperatures. Stillbelow the melting point. Interestingly they loose the ability to beattracted to a magnet at these elevated temperatures as the molecules atthose temperatures are not in any particular alignment. They can be made softer and and more ductile by controlled heating andcooling at temperatures well below their melting point. The reason thatwe post heat and cool the welds slowly. (see tempering and annealing)The point is that we should take every effort to follow the steelmanufacturer's recommended practices when working with steel alloys. (BTW all steels are alloys and the differing ingredients,( 41xx seriessteels are alloyed with Chromium and Molybdenum), are what make thesteel suitable for each application.)I would recommend that we as builders follow established buildingpractices. A trip to the library should turn up a few good referencetexts on the steels and other metals used in our hobby.After all, the reasons we are allowed to build our own aircraft (atleast in Canada) are recreation and education.John Mc-----Original Message-----

Original Posted By: Mike Cunningham
>Sir;> Engineering matters aside, one of the first things the FAA guys look for>around here is just that......."...did ya bend with the grain or agin'>it...?">Earl MyersI concur here with Earl and even if the FAA boys don't ask you this,you will sleep better at night if you follow the suggested patterns asshown in Tony Bingelis's books and other publications.The grain goes with the printing on both sheet alum. and 4130 sheet.Also file out ALL your saw marks on the edges of every fitting filing long wise on the fitting edges, not perpendicular. Corners should beradiused too- easy to do inside corners by drilling the corner first, thencutting to that point. Mike C. ________________________________________________________________________________

Original Posted By: walter evans
Hi Walt,Thanks for the info. I have seen that picture before! very interesting!-----Original Message-----

Original Posted By: dannymac
It is "BEST" to cut sheet with the grain for strap type fittings andespecially if you are going to bend them, the bend accross the grain. Mostof the time, the "grain" is easily seen if you tilt the sheet and let lightbounce off of it......and it should go with the lettering. I always buy theprecut strap stuff as it cuts down the butchering time and makes neat cutsthat you don't have much touch up to do.........REMEMBER<REMEMBER<REMEMBER,the FAA Inspector MAY ask you about this "grain" thing and a lot of other"trick " questions. Some of these guys don't know squat about airplanebuilding, they just go down a checklist. Others (few) know "too much" andknow exactly what to look for or ASK about.......especially fuel lineplacement and materials.Earl-----Original Message-----

Original Posted By: Phil Phillips
> Subject: grain in 4130 sheets>>> Make sure that when you make brackets and fittings, that you cut them >from sheet "with the grain" of the sheet.> The grain runs with the printing on the sheet.> And any fitting that you cut out with a grinder,where the wheel can >cause hot spots, make sure that you normalize the piece. Unless it will be >welded, which will take care of that anyway.> walt________________________________________________________________________________

Original Posted By: SAM & JAN MARINUCCI
>> Subject: grain in 4130 sheets>>>>>> Make sure that when you make brackets and fittings, that you cut them>>from sheet "with the grain" of the sheet.>> The grain runs with the printing on the sheet.>> And any fitting that you cut out with a grinder,where the wheel can>>cause hot spots, make sure that you normalize the piece. Unless it willbe>>welded, which will take care of that anyway.>> walt>>>________________________________________________________________________________

Original Posted By: walter evans
>>> Subject: grain in 4130 sheets>>>>>>>>> Make sure that when you make brackets and fittings, that you cutthem>>>from sheet "with the grain" of the sheet.>>> The grain runs with the printing on the sheet.>>> And any fitting that you cut out with a grinder,where the wheel can>>>cause hot spots, make sure that you normalize the piece. Unless it will>be>>>welded, which will take care of that anyway.>>> walt>>>>>>________________________________________________________________________________

Original Posted By: Warren Shoun
>>> Subject: grain in 4130 sheets>>>>>>>>> Make sure that when you make brackets and fittings, that you cutthem>>>from sheet "with the grain" of the sheet.>>> The grain runs with the printing on the sheet.>>> And any fitting that you cut out with a grinder,where the wheel can>>>cause hot spots, make sure that you normalize the piece. Unless it will>be>>>welded, which will take care of that anyway.>>> walt>>>>>>>________________________________________________________________________________

Original Posted By:> >> walter evans
> Subject: Re: grain in 4130 sheets>> >I myself have no refrence on what happens to steel that has been ground too> >hot, but if any one would like to test the theroy, just take two pieces of> >steel, grind one till it turns blue, and then try to cut both with a file.> >> >The blue one will have been hardened by heat, and air. A hrdened part it> >brittle, and subjuct to crackes.> >> >> >>From: Mike Cunningham > >>Reply-To: Pietenpol Discussion > >>To: Pietenpol Discussion > >>Subject: Re: grain in 4130 sheets> >>Date: Fri, 18 Jun 1999 13:16:04 -0500> >>> >>Walt, I have not heard of this. As a newbie to homebuilding I have read> all> >>of Tony B's books and most of the EAA stuff.> >>I can remember reading that grain doesn't matter in flat pieces but should> >>be perpendicular to any bends whenever possible.> >>Also haven't seen anything before about normalizing fittings after> >>grinding. Some of my fittings did get those little brownish> >>spots on the edges where I got em a little hot. Can you give a little more> >>info for reference?> >>-----Original Message-----

Original Posted By: Larry Ragan
> >> Subject: grain in 4130 sheets> >>> >>> >> Make sure that when you make brackets and fittings, that you cut them> >>from sheet "with the grain" of the sheet.> >> The grain runs with the printing on the sheet.> >> And any fitting that you cut out with a grinder,where the wheel can> >>cause hot spots, make sure that you normalize the piece. Unless it will> be> >>welded, which will take care of that anyway.> >> walt> >> >> >________________________________________________________________________________