Go Back OFN Forums > Fabrication > Fabrication 101

Fabrication 101 Everyone has to start somewhere and for some, theOFN might be that somewhere.


Fabrication 101 Everyone has to start somewhere and for some, theOFN might be that somewhere.

Reply
 
Thread Tools
  #1  
Old 11-07-2008, 01:19 PM
Themistaken's Avatar
Themistaken Themistaken is offline
Junior Fabricator
 
Join Date: Sep 2008
Location: Lewes Beach, DE
Posts: 29
DOM vs 4130 tubing

So I have tried to do some searches on the topic and have come up with a little bit of information but not enough to sway me either way. I am getting ready to start making a new cage for the rig for this upcoming season. This cage is going to be used for rock-crawling if it makes a difference other then it getting flopped onto a few times. I have gotten quotes from several local distributors on 4130 and DOM in the 1.75" .120 range. What blew my mind was the 4130 quote being at $4.00/ft ($1/ft more then the DOM quote). So that is where my interest got sparked.

Is the 4130 worth the extra money? Would I really be able to save any weight? I do not know of any places tht would be able to do the heat treating after I weld it all together. Is 4130 really that much stronger then DOM? Any suggestions or any good read links? Thanks!
Reply With Quote
  #2  
Old 11-07-2008, 01:38 PM
mikefrombc's Avatar
mikefrombc mikefrombc is offline
Master Fabricator
 
Join Date: Oct 2008
Location: Whonnock BC CANADA
Posts: 1,110
the tubing all weighs the same for the same od and wall thickness , Moly is stronger so you can use a thinner wall and have the same strength in dragracing they spec either 1 5/8" OD with a .118" wall for DOM/ERW and for moly they spec a .083" wall with the same OD that,s where the weight savings comes in . moly everything HAS to be TIGGED !!!! so that makes onsite repairs harder if you don,t have a tig .
Reply With Quote
  #3  
Old 11-07-2008, 01:40 PM
entropy's Avatar
entropy entropy is offline
This space for rent.
 
Join Date: Sep 2007
Location: ~40Miles from the center of Oregon
Posts: 7,296
IF And that is a big if this gets a clear answer it should be made a sticky or put in a FAQ.

"Generally" I will say if you are not going to compete, or do not have a weight fetish, or do not have $$$$ to just burn to build a CrMo cage correctly; then use DOM.
I would, will, and have even for a Comp Rig in this application.
__________________
“No matter what people tell you, words and ideas can change the world.” RW
Reply With Quote
  #4  
Old 11-07-2008, 01:52 PM
cagedruss's Avatar
cagedruss cagedruss is offline
Master Fabricator
 
Join Date: Sep 2007
Location: Portland Oregon
Posts: 206
OK, here is the info I use for 4130. I have used 4130 for drag, road race and rock crawl with out any failure of any type. It cuts the same, bends the same and welds the same. It is approx. a 1/3 stronger to it 1020 counter part.

Also, I have repaired numerous stock car chassis at the track using a wire feed welder. The Er60-s worked just fine. I attached an article from Lincoln Welding that has served me well for the past 8 years. It answers all of the myths of welding 4130.

http://www.lincolnelectric.com/knowl...hrome-moly.asp



Quote:
Originally Posted by Themistaken View Post
So I have tried to do some searches on the topic and have come up with a little bit of information but not enough to sway me either way. I am getting ready to start making a new cage for the rig for this upcoming season. This cage is going to be used for rock-crawling if it makes a difference other then it getting flopped onto a few times. I have gotten quotes from several local distributors on 4130 and DOM in the 1.75" .120 range. What blew my mind was the 4130 quote being at $4.00/ft ($1/ft more then the DOM quote). So that is where my interest got sparked.

Is the 4130 worth the extra money? Would I really be able to save any weight? I do not know of any places tht would be able to do the heat treating after I weld it all together. Is 4130 really that much stronger then DOM? Any suggestions or any good read links? Thanks!
Reply With Quote
  #5  
Old 11-07-2008, 02:17 PM
mikefrombc's Avatar
mikefrombc mikefrombc is offline
Master Fabricator
 
Join Date: Oct 2008
Location: Whonnock BC CANADA
Posts: 1,110
Quote:
Originally Posted by cagedruss View Post
OK, here is the info I use for 4130. I have used 4130 for drag, road race and rock crawl with out any failure of any type. It cuts the same, bends the same and welds the same. It is approx. a 1/3 stronger to it 1020 counter part.

Also, I have repaired numerous stock car chassis at the track using a wire feed welder. The Er60-s worked just fine. I attached an article from Lincoln Welding that has served me well for the past 8 years. It answers all of the myths of welding 4130.

http://www.lincolnelectric.com/knowl...hrome-moly.asp

it,s funny Lincoln tells you you CAN weld 4130 with mig but when it comes to a dragracing application SFI and NHRA mandate the only welding for 4130 is TIG only . as for moly spend some time on yellowbullet .com and there,s tons of images of moly cars that are broken from crashes , some of the breaks and where they happen are amazing , most breaks are not at the weld but around the weld area .

as for bending it i,m not gonna agree that it bends the same we bend tubing all day on a cnc mandral bender and moly is always a pain , we,ve had tubing tear apart only 30deg into a bend . that gets scary
Reply With Quote
  #6  
Old 11-07-2008, 02:41 PM
Themistaken's Avatar
Themistaken Themistaken is offline
Junior Fabricator
 
Join Date: Sep 2008
Location: Lewes Beach, DE
Posts: 29
Quote:
Originally Posted by mikefrombc View Post
as for moly spend some time on yellowbullet .com and there,s tons of images of moly cars that are broken from crashes , some of the breaks and where they happen are amazing , most breaks are not at the weld but around the weld area .

as for bending it i,m not gonna agree that it bends the same we bend tubing all day on a cnc mandral bender and moly is always a pain , we,ve had tubing tear apart only 30deg into a bend . that gets scary

Would that not have to do with the metal annealing after it is welded and then not being properly heat treated again. I am not a subject matter expert by any means, but more or less thinking out loud.


We do compete with the rig, but all that our rules have ever stated are the number of mounting points tied to the frame, passes safety inspection, and such. Nothing about methods of welds. I have never MIGed Chro-Moly, but I do not want my cage to be the first time... As far as TIG in general goes, my skills in that are lacking due to maybe doing it once a month. Much more comfortable with MIG.
Reply With Quote
  #7  
Old 11-07-2008, 02:41 PM
cagedruss's Avatar
cagedruss cagedruss is offline
Master Fabricator
 
Join Date: Sep 2007
Location: Portland Oregon
Posts: 206
With out getting into a pissing match I stated what has worked for me for the last 8 years.

My little JD model 3 hydro has bents countless bends in 1.625" .083" and 1.75"x.120" using a 5.5 clr for over 6 years and has never struggled or broke a piece of tube. I can not answer to anybody else's experiences or machines.

As to websites showing broken tubing I have seen both 1020 and 4130 break. It breaks near the weld where the material was heated. I can show you pictures of Roll cages that broke 3' from a weld and 1/4" from the weld.That is a given in all welding jobs. It is kind of like Commercial flying, plane do crash but it is a very minute number.

material is chosen by the user based on availability and user's experience. I was a little stressed at first using 4130 for customers so I built a project for me to try it out. I also studied with another shop to gain experience and practiced welding and had my welds tested.

I prefer 4130 over 1020, it has properties that work well for Motorsports. I do not think it is for everybody or every application.


Good luck with your project!
Reply With Quote
  #8  
Old 11-07-2008, 03:42 PM
Defender Chassis's Avatar
Defender Chassis Defender Chassis is offline
Master Fabricator
 
Join Date: Nov 2006
Location: Mid-Ohio Valley
Posts: 359
Quote:
Originally Posted by mikefrombc View Post
it,s funny Lincoln tells you you CAN weld 4130 with mig but when it comes to a dragracing application SFI and NHRA mandate the only welding for 4130 is TIG only .
It is my belief that NHRA/IHRA/SFI require a TIG process for 4130 so that the weekend warriors stay away from it.

I personally do not like to use a MIG on tubing for anything more than tack welds. Maybe its my skill level or the confined spaces I work but the starts and stops scare me with respect to cold laps.

It is also worth noting that some of the yield strength published for DOM material will be lost during the welding process. This is because DOM tubing gains some strength because it is cold worked during forming.

The fact is there is no clear answer to your question..........

The only real answer is:

It depends!
Reply With Quote
  #9  
Old 11-07-2008, 04:01 PM
kkuenemann's Avatar
kkuenemann kkuenemann is offline
Master Fabricator
 
Join Date: Feb 2007
Location: Longview, TX
Posts: 275
Quote:
Originally Posted by cagedruss View Post
OK, here is the info I use for 4130. I have used 4130 for drag, road race and rock crawl with out any failure of any type. It cuts the same, bends the same and welds the same. It is approx. a 1/3 stronger to it 1020 counter part.

Also, I have repaired numerous stock car chassis at the track using a wire feed welder. The Er60-s worked just fine. I attached an article from Lincoln Welding that has served me well for the past 8 years. It answers all of the myths of welding 4130.

http://www.lincolnelectric.com/knowl...hrome-moly.asp
Quote:
Originally Posted by mikefrombc View Post
it,s funny Lincoln tells you you CAN weld 4130 with mig but when it comes to a dragracing application SFI and NHRA mandate the only welding for 4130 is TIG only . as for moly spend some time on yellowbullet .com and there,s tons of images of moly cars that are broken from crashes , some of the breaks and where they happen are amazing , most breaks are not at the weld but around the weld area .

as for bending it i,m not gonna agree that it bends the same we bend tubing all day on a cnc mandral bender and moly is always a pain , we,ve had tubing tear apart only 30deg into a bend . that gets scary

Where in the Lincoln article does it say that MIG welding is OK? Also, Where does it say that "Er60-s worked just fine", when the RECOMMENDED filler is ER80S-D2??

This topic has been on here before with lots of input from a lot of different people. The reality is if you are going to use the 4130 tubing, more care needs to be put into weld prep, joint fit, welding process and filler material selection.

Lastly, I agree with the reason listed above on which is better "it depends".
__________________
Karl
aka Aggie91
Reply With Quote
  #10  
Old 11-07-2008, 04:30 PM
mikefrombc's Avatar
mikefrombc mikefrombc is offline
Master Fabricator
 
Join Date: Oct 2008
Location: Whonnock BC CANADA
Posts: 1,110
Quote:
Originally Posted by kkuenemann View Post
Where in the Lincoln article does it say that MIG welding is OK? Also, Where does it say that "Er60-s worked just fine", when the RECOMMENDED filler is ER80S-D2??

This topic has been on here before with lots of input from a lot of different people. The reality is if you are going to use the 4130 tubing, more care needs to be put into weld prep, joint fit, welding process and filler material selection.

Lastly, I agree with the reason listed above on which is better "it depends".

it,s not stated in that article but in a another thread on a aonther site there was a similair thread and someone posted links to Lincoln and them talking about mid welding moly for use in small aircrafts and such
Reply With Quote
  #11  
Old 11-07-2008, 04:32 PM
mikefrombc's Avatar
mikefrombc mikefrombc is offline
Master Fabricator
 
Join Date: Oct 2008
Location: Whonnock BC CANADA
Posts: 1,110
Quote:
Originally Posted by Defender Chassis View Post
It is my belief that NHRA/IHRA/SFI require a TIG process for 4130 so that the weekend warriors stay away from it.

I personally do not like to use a MIG on tubing for anything more than tack welds. Maybe its my skill level or the confined spaces I work but the starts and stops scare me with respect to cold laps.

It is also worth noting that some of the yield strength published for DOM material will be lost during the welding process. This is because DOM tubing gains some strength because it is cold worked during forming.

The fact is there is no clear answer to your question..........

The only real answer is:

It depends!
have you tried pulsed mig yet ?? it,s pretty cool gets good penetration and the wire never actually touches the steel , sounds like a pissed off hornet while welding too . we just got the Miller 350P a few months back and the guys like it so far
Reply With Quote
  #12  
Old 11-07-2008, 05:43 PM
cagedruss's Avatar
cagedruss cagedruss is offline
Master Fabricator
 
Join Date: Sep 2007
Location: Portland Oregon
Posts: 206
The reference to ER60S2 was just that. Actually is was supposed to be ER70-S2, that was the wire the guy had in his 110 welder at the speedway when I reattached his suspension and a tube to his 4130 chassis.


Don't confuse that with me using a mig at the shop. I only use the Tig, per NHRA rules. I was just trying to explain that in a crisis situation (trail/track) that a Mig would work to make temporary fixes.
Reply With Quote
  #13  
Old 11-07-2008, 05:51 PM
Themistaken's Avatar
Themistaken Themistaken is offline
Junior Fabricator
 
Join Date: Sep 2008
Location: Lewes Beach, DE
Posts: 29
Good info thank you. I really just need to get a stick or 2 and play around with it and practice my TIG skills. Best way to learn with the 4130 I suppose. We'll see where we get with it in a month or 2 and then make our materials decision. DOM or MIG welding it hasn't let me down in my dozen or so flops/belly-ups on 2 or 3 different cages... (I know, cages should only be rolled/flopped once, but it gets to expensive to replace a cage 5 or 6 times a year)
Reply With Quote
  #14  
Old 12-24-2008, 08:02 AM
astjp2's Avatar
astjp2 astjp2 is offline
Junior Fabricator
 
Join Date: Dec 2008
Posts: 4
Quote:
Originally Posted by mikefrombc View Post
the tubing all weighs the same for the same od and wall thickness , Moly is stronger so you can use a thinner wall and have the same strength in dragracing they spec either 1 5/8" OD with a .118" wall for DOM/ERW and for moly they spec a .083" wall with the same OD that,s where the weight savings comes in . moly everything HAS to be TIGGED !!!! so that makes onsite repairs harder if you don,t have a tig .
If you TIG moly, you need to preheat and post heat. I know that the airplane guys are not allowed to TIG without pre and post heat. Most actually oxy/actylene weld 4130, it allows for the most consistant normalizing upon air cooling and the heat affected zone has less tendancy to crack. Tim

PS if anybody wants references, I can provide them the official FAA docs....

Last edited by astjp2; 12-24-2008 at 08:06 AM.
Reply With Quote
  #15  
Old 12-24-2008, 10:44 AM
mikefrombc's Avatar
mikefrombc mikefrombc is offline
Master Fabricator
 
Join Date: Oct 2008
Location: Whonnock BC CANADA
Posts: 1,110
Quote:
Originally Posted by astjp2 View Post
If you TIG moly, you need to preheat and post heat. I know that the airplane guys are not allowed to TIG without pre and post heat. Most actually oxy/actylene weld 4130, it allows for the most consistant normalizing upon air cooling and the heat affected zone has less tendancy to crack. Tim

PS if anybody wants references, I can provide them the official FAA docs....
SFI/NHRA apec NORMALIZED 4130 it does not need any pre or post heat , this is a serious discussion in the last few yrs top fuel cars that had anytype of heating where facturing one driver lost his life
Reply With Quote
  #16  
Old 03-29-2009, 01:29 PM
dezertracerdude's Avatar
dezertracerdude dezertracerdude is offline
Junior Fabricator
 
Join Date: Nov 2008
Location: phelan, ca
Posts: 11
Quote:
Originally Posted by mikefrombc View Post
the tubing all weighs the same for the same od and wall thickness , Moly is stronger so you can use a thinner wall and have the same strength in dragracing they spec either 1 5/8" OD with a .118" wall for DOM/ERW and for moly they spec a .083" wall with the same OD that,s where the weight savings comes in . moly everything HAS to be TIGGED !!!! so that makes onsite repairs harder if you don,t have a tig .
I know and have worked with alot of BIG NAME offroad teams that MIG chromo all the time with no problems and most don't post heat either.
Reply With Quote
  #17  
Old 03-29-2009, 02:44 PM
qscycleservice's Avatar
qscycleservice qscycleservice is offline
Junior Fabricator
 
Join Date: Jun 2006
Location: Richmond, VA
Posts: 17
I have made several swingarms for motorcycles out of bothe materials. The weight savings wasn't enough per teh cost of 4130. We use DOM mostly and 4130 for personal stuff and any bike that makes over 175hp Once its painted who knows what it is. Most circle track cars they use ERW. They can take hits at over 100mph into concrete walls. My .02
Reply With Quote
  #18  
Old 04-18-2009, 09:22 PM
87RangerRyan's Avatar
87RangerRyan 87RangerRyan is offline
Junior Fabricator
 
Join Date: Mar 2008
Location: Orange County
Posts: 17
I havent read the whole thread but heres my input.

If you arent tig welding it id use DOM. But if you tig weding I highly recommend using 4130. 1.00 more per foot isnt to bad I dont think.
Reply With Quote
  #19  
Old 04-18-2009, 11:48 PM
zancat's Avatar
zancat zancat is offline
Master Fabricator
 
Join Date: Sep 2007
Location: Ramona, Ca
Posts: 377
Weld two pieces of each together and try to break them apart. Then make up your own mind. Do it with a couple pieces of CREW too. You'll probably never use CREW again for anything.

Zancat
__________________
Desert-Craft Inc.
Ramona, CA
www.desert-craft.com
Pro-Tools Dealer
Reply With Quote
  #20  
Old 04-19-2009, 02:23 AM
entropy's Avatar
entropy entropy is offline
This space for rent.
 
Join Date: Sep 2007
Location: ~40Miles from the center of Oregon
Posts: 7,296
41xx steel... It would be nice to see real world information derived using the scientific method that definitively puts this to rest.
On one NHRA car the entire chassis went to be heat treated after construction.
I've dealt with Aircraft that heat treated with a rosebud and a non contact Term, and before that with heat sticks or crayon.
I've also seen it gas welded with no post process, and yes I have seen it MIG'd.
I have seen the results of impact as in wrecked and they all seem to hold up about the same, although the "Funny Car Chassis" sustained the most severe impact and clearly it saved the driver even if he sustained simply massive trauma.

Perhaps someday...
__________________
“No matter what people tell you, words and ideas can change the world.” RW
Reply With Quote
Reply

Bookmarks


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 12:03 PM.

Powered by vBulletin® Version 3.8.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Template-Modifications by TMS
Copyright ©2012, Offroad Fabrication Network