basic tech, Model A frame fabrication

earlier this week I picked up a couple sticks of 2x4x.120 rectangle steel tubing
with the intent of making a Model A frame
partly because I will be needing one soon
partly as an exercise and also to see if I wanted to try to make them for sale

I have a straight but crusty stock frame to use as reference
so I got started on it yesterday,
first I made a pattern of the frame horn..
because it makes sense to start at that end

and transfered that to the tubing
then shifted the pattern to layout the actual cut line
I will leave the rolled edge and make the weld on the flat

 

then using a snipped off blade in the sawsall
I first made the long straight cut along the bottom of the tube,
followed by the long curve

rolled it over and layed out and cut the opposite side

 

then I ground all edges clean to the scribe lines
clamped it to check fit and final shape with the pattern

took the clamps off
ground a bevel along the joint
clamped and tacked it to hold
reclamped it to the frame table to keep it straight
an welded the first side up

 

then after it had cooled

I rolled it over and clamped it with the opposite face up
tacked it
and weled it too

 

ground the welds down,
with the deep bevel and a good weld this makes a nice clean joint
with minimal weld material removed

 

next I trimmed the short curve at the top of the rail
beveled the edges
and clamped the soft part of the curve

 

checked the shape with the pattern again,
welded that up,

trimmed the excess strip at the bottom

rolled the top strip over the tip,
checked it's shape with the pattern again
and welded the end up

 

then I layed out the slice at the inside of the horn to look similar to the stock frame

trimmed it with the little grinder with a thin disc

and cleaned it all up

 

so
there is one frame rail horn with a shape very similar to the Stock Model A shape

 

need two rails to make an A frame

so,
following the same procedure

a twin was born..

that was yesterday,
today I will try to make them look more like a frame

 

Are you adopting?

 

beauty!

how did you get the roll on the end like that? that's a nice curve.

 

Thats badass....

 

nice clean work.

 

Great job, nice job on showing the steps......Littleman

 

in one of the last pictures you can see the torch hoses,
using a rose bud I warmed the tip to dull red
and using the head of a ball peen hammer as a dolly I massaged it into shape
cleaned it up with the disc sander and a touch with the file

 

my childhood:
do I have to stop the car right now?
just wait till your father gets home!
what do you think this is? Leave it to Beaver?
go out behind the barn and pick a switch, a good one! not one that's going to break!
are you crying?!?, I'll give you something to cry about!


you want to take the chance of reliving that?

 

Thats exactally what we did on my frame. works, looks good.

 

Hey 60 are you using the recip. saw for all your cutting? did you cut the plate for the horns with it? This is an awesome post.
Gabe

 

Killer work...... I'm impressed !

 

Excellent work! BTW, did you have any problems with the sides curling in ever so slightly after cutting the bottom taper?

 

Very nice....Gonna keep this post in mind.

 

Great work as always !!!

 

beautiful!!

Are you going to recess the box for the front crossmember,or trim it and weld it flush?
I ask because used original rails on Sciflyer72's frame and a so-cal dropped crossmember, and after many,many measurments, I discovered that the damn thing(crossmember) had been stamped with the center hole off center by almost 1/4 inch!

we trimmed one side to center it in the frame, but if we were going to weld on the outside of a box, it could have been more problematic. (and look a little wonky,at that. )
just a heads up. looks like you can probably build your own darn crossmember,anyway.

 

Any reason why you didn't use beefier tubing... ie; 3/16?

 

That's beautiful work.

Slonaker

 

Hi Gabe,
I did use the sawsall for all but the tight curve, I used the grinder with thin blade there as well as the tapered inside at the front

I have a plasma cutter but thought I want a little less distortion,
a sharp saw blade cuts pretty quick, but I may try the plasma on the next one.

 

on one of the four sides it did come in just a hair,
I should have taken a picture
but I took a heavy length or round stock held perpendicular to the rail on the strip side with the end just beyond the bevel, tacked it and used it as a lever against the strip edge to gently pull the flat up

if that makes sense to you

 

I'm using a store bought front cross member too,
and yes I had planned on trimming it to fit

 

I actually went shopping for just that,
but the only steel outlet in reasonable distance was out of it...

I would have liked heavier.. to take more abuse (horsepower) and keep the center of gravity a bit lower

but I think this will do fine.