Author Topic: 1926 Model T XO/VFCC  (Read 61076 times)

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Offline swackerle

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Re: 1926 Model T XO/VFCC
« Reply #45 on: June 25, 2012, 04:21:17 AM »
Perhaps this pic will help show the angles of how I put things together.  I might cross brace it if I have some tube left over.


Offline Dr Goggles

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Re: 1926 Model T XO/VFCC
« Reply #46 on: June 27, 2012, 07:25:11 PM »
Perhaps this pic will help show the angles of how I put things together.  I might cross brace it if I have some tube left over.



I'd be having a rethink on that design. If you want to go with that concept there are various ways to achieve it without everything being in tension like that. I'd be having a close look to see that those welds are getting full penetration, are you running them hot enough?

The shocks transmitted through that arrangement can be quite severe and "hanging" everything like that means a failure in just one of those welds could cause a pretty serious upset.Larger dia. pipe will vastly increase the strength, or using a plate instead. Ideally having the axle under the chassis rail would alleviate the basic concerns and change the stresses on the joins.Doing that would also allow you to use some sort of compliance on the front like bumpstops or something.
Few understand what I'm trying to do but they vastly outnumber those who understand why...................

http://thespiritofsunshine.blogspot.com/

Current Australian E/GL record holder at 215.041mph

THE LUCKIEST MAN IN SLOW BUSINESS.

Offline DND

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Re: 1926 Model T XO/VFCC
« Reply #47 on: June 28, 2012, 03:11:59 AM »
Hi Model T

I second what the DR says, and if you stay with the axle on top you should gusset the heck out of it.

Starting at the axle end where your angle tubes come up to meet the kingpin boss, and put a wrap around strap around the outside of the boss and down those angled tubes and put gussets on all those tube joints.

In that kind of a load on the axle you can not have too many gussets, as you wan't to keep the shiny side up and rubber side down !!!

Don

Offline Peter Jack

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Re: 1926 Model T XO/VFCC
« Reply #48 on: June 28, 2012, 04:07:32 AM »
PM sent.

Offline manta22

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Re: 1926 Model T XO/VFCC
« Reply #49 on: June 28, 2012, 12:50:32 PM »
Frankly, unless your car is extremely heavy, I think you are OK. It won't hurt to add gussets if you feel that you need them. The quality of your welds is, of course the key to success.

Regards, Neil  Tucson, AZ
Regards, Neil  Tucson, AZ

Offline swackerle

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Re: 1926 Model T XO/VFCC
« Reply #50 on: June 28, 2012, 08:07:54 PM »
This is exactly why I wanted to post this build on the forums here.  I am a rookie in every respect and need all the input I can get!  I am going to add a few more pieces to the front end.  In situations like this, more is certainly better.

Also I took some better pictures of my welds.  I think that biggest problem is the quality of camera (cell phone) and shadows.  I got out the good camera and took a few shots, so let me know if there you have any suggestions for improvement. 





Thanks guys,
Sam

Offline saltwheels262

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Re: 1926 Model T XO/VFCC
« Reply #51 on: June 28, 2012, 08:27:27 PM »






Thanks guys,
Sam

they all look good to me.
the weld in picture 1 and the right side of number 2 look like they were done by a different person than the left side picture number 2.

why is there a gap in the welds?

this is coming from a guy with a fair eye and is not a welder.
bub '07 - 140.293 a/pg   120" crate street mill  
bub '10 - 158.100  sweetooth gear
lta  7/11 -163.389  7/17/11; 3 run avg.-162.450
ohio -    - 185.076 w/#684      
lta 8/14  - 169.xxx. w/sw2           
'16 -- 0 runs ; 0 events

" it's not as easy as it looks. "
                            - franey  8/2007

Offline manta22

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Re: 1926 Model T XO/VFCC
« Reply #52 on: June 28, 2012, 08:53:09 PM »
"why is there a gap in the welds?"

I don't know where these welds are but the rule book specifies stitch welds on roll cage gussetts. This is to keep a crack from propagating completely along the length of a gussett.

Regards, Neil  Tucson, AZ

Regards, Neil  Tucson, AZ

Offline Dr Goggles

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Re: 1926 Model T XO/VFCC
« Reply #53 on: June 28, 2012, 09:57:54 PM »
Hey Sam,
Those welds look OK. For your own satisfaction spend a bit of time welding similar things that you are using on the car and then giving them hell with a BFH. You should be able to completely mangle a piece of 1&3/4 tube  which you have welded to a rail. If you crack the weld or break it out along the bead line then it is of less than ideal strength. First you need to satisfy yourself that you are getting full penetration, then you need to work on tidier beads, tidier beads have less potential for crack propagation. Many people will say " the neater the bead the better the weld", if the penetration is good" that's pretty close to right....

You're right about "putting it out there" too. I'm one for putting all of your exploits in the public view, if there's something wrong you'll know about it way sooner than Secret Squirrel will with his well hidden poorly conceived ideas, you'll learn way faster and get stuff done quicker.

Is that gasless you're using?.....it looks very spattery, are you keeping your torch clean? Consider some inox spray to save it sticking everywhere.

My only suggestion is to get in a bit of practice on mismatched thicknesses. It's much easier to control heat and penetration of two identical pieces, that changes when you are welding light to heavy and the risk of poor penetration on the heavier guage occurs, the piece of tube onto the rail above could maybe do with a little more wire speed , less "cross-stitching" and more focus on the rail than directly at the root of the joint. I say that because the weld has undercut the  tube slightly, which contrasts with the edge of the bead on the rail, "cross-stitching" will allow more fill and dissipate heat but has left a ragged finish to the bead, by allowing the bead to flow out a little more it will run a little hotter, focusing that heat more at the rail than the root of the joint will increase the penetration on the rail, lessen the burn on the tube and give a better finish to the bead.
Few understand what I'm trying to do but they vastly outnumber those who understand why...................

http://thespiritofsunshine.blogspot.com/

Current Australian E/GL record holder at 215.041mph

THE LUCKIEST MAN IN SLOW BUSINESS.

Offline saltwheels262

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Re: 1926 Model T XO/VFCC
« Reply #54 on: June 28, 2012, 10:30:12 PM »
"why is there a gap in the welds?"

I don't know where these welds are but the rule book specifies stitch welds on roll cage gussetts. This is to keep a crack from propagating completely along the length of a gussett.

Regards, Neil  Tucson, AZ



i understand now.
thank you.

not a roll cage guy either.
bub '07 - 140.293 a/pg   120" crate street mill  
bub '10 - 158.100  sweetooth gear
lta  7/11 -163.389  7/17/11; 3 run avg.-162.450
ohio -    - 185.076 w/#684      
lta 8/14  - 169.xxx. w/sw2           
'16 -- 0 runs ; 0 events

" it's not as easy as it looks. "
                            - franey  8/2007

Offline rgn

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Re: 1926 Model T XO/VFCC
« Reply #55 on: June 28, 2012, 10:42:23 PM »
Hi Sam, It's amazing how much a little bit of weld will hold, it's also amazing how quickly a little crack or defect under load will turn into a failure.  It's hard to tell looking at the screen of the computer, but the l/h side of the unpainted butt joint looks as if it may be undercut?  A welding defect is anything that compromises the usefulness of the finished weld. 

Undercutting reduces the cross-sectional thickness of the base metal, and reduces the strength of the weld and material.  The weld and the undercut area becomes the weak point in the sum of parts.  Undercut is usually a product of excessive current or too little wire feed.  If you are using gasless as the Dr suspects, think about renting a bottle gas suited to the metal type you are using, it makes a huge amount of difference.

Any of you used the new generation of inverter migs?  No splatter at all and they weld like wow and don't cause your electrical meter to jump off it's pivot.

Offline swackerle

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Re: 1926 Model T XO/VFCC
« Reply #56 on: June 28, 2012, 11:32:46 PM »
Wow!  Thanks to everyone for all the advise!

-I am using a gasless welder, hence all the splatter.

-I will try to keep in mind aiming the feed more towards the frame (or heavier metal) to prevent undercutting from here on and redo a few strategic welds.

-I am going to heed the advice of Dr. Goggles (mostly because of the Dr. part :-D) and take my 4 pound sledge to a weld and do my damnest to break it.  Though I know this isn't a completely accurate representation of the forces acting upon the cage and other pieces, I feel that it will at least let me know how my welding stacks up.

-The gap in the gussets is for the rulebook, just like Neil said.  Also one side is left handed, the other is right handed, hence the difference.

Thanks again guys.  Progress is slow, but at least it's heading in the right direction with alittle help from everyone.

-Sam

Offline zenndog

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Re: 1926 Model T XO/VFCC
« Reply #57 on: June 29, 2012, 12:30:09 AM »

Undercutting reduces the cross-sectional thickness of the base metal, and reduces the strength of the weld and material.  The weld and the undercut area becomes the weak point in the sum of parts.  Undercut is usually a product of excessive current or too little wire feed.  If you are using gasless as the Dr suspects, think about renting a bottle gas suited to the metal type you are using, it makes a huge amount of difference.


There are many guys on this site that are probably expert welders....I am not one of them.

That said, I think you should increase the wire feed. Looks like you are penetrating but not filling enough wire into the "puddle".

On the front axle I can't tell but it looks to me like you were not getting enough penetration and you have blobs of "wire" that are sitting there on the surface of the joint. Does anyone else see that? It is hard to tell because those shots are not close ups.

I think you should invest in a gas bottle for your welder as another person suggested, it is really a low cost compared to what you are undertaking and you will like it. I didn't notice but did you mention if your welder is 220 or 110?

Love this build, go man go! Again, I think it is great that you are just getting out there and doing it.

Offline DND

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Re: 1926 Model T XO/VFCC
« Reply #58 on: June 29, 2012, 01:27:20 AM »
Hi Sam

Maybe you can find a weld shop in your area, take some of your pics and show the man.

Also you could pay him for a bit of time for a lesson or two, then you have an idea of what to shoot for.

I took a nite school welding class and that was one of the best things i ever did, not only to weld but you learn about the safety of welding too.

Don

Offline Peter Jack

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Re: 1926 Model T XO/VFCC
« Reply #59 on: June 29, 2012, 01:49:34 AM »
I sent you one more PM. I like the welds you're showing here with the exception that maybe you're travelling just a little too fast.

Using a little manipulation where you go a little forward and then about half the distance back and repeat over and over might also help.

The project continues to look good.  :cheers: :cheers: :cheers:

Pete