Rusty hatch

[festy]

When I went to open my track car's hatch for the first time in about 5 years, it was clear that it had seen better days.
There was rust in all the usual spots, and a few unusual spots too. So I thought I'd better pull it off and give it a quick patch up, until I can come back and fix it properly one day (i.e. make it future-me's problem)

So off it came, and popped the glass out to see what I was up against.

Doesn't look tooooo bad:


err...


umm...


 


So maybe a little worse condition than I first thought?


ok, but the frame is solid, right?


 


 
Yeah ok, that's well beyond a quick patch-up job. Time to learn some basic sheet metal skills, seeing as rust-free hatches are rather hard to come by these days. 
Future-me, you're off the hook because present-me is going to take one for the team  

[festy]

So why not dive straight in the deep end and start on the lower window corners 
I was going to have to replace a number of sections of the window channel, which involves two 90° bends plus a little raised lip.
Not easy to do on a bender (not that I have one), but what about hammer forming over a wooden buck? The guy on the youtube video made it look so easy...

So I chucked a wooden block in the mill and made myself a buck form, I even added in allowance for the sheet metal thickness. Easy so far... 

And the result 


ok then, plan B - make a simple bender, buy a cheap bead roller and step dies, and maybe make a tipping die for it because they look so easy to get great results with on all the youtube videos 

But in the meantime maybe start with some of the simpler frame patches.

This looked like a good place to start:


I made the dogleg lip by first bending a 90° angle then clamping the piece flat between two steel plates, clamping a 6mm bar hard up against the outside of the bend, and hammering the edge over it.
Or if I'd waited a couple of days for my bead roller to be delivered, it would have been a 20 second job 



Getting ready to weld the first patch in:

[festy]

I had no clue how to go about making a new lower frame corner, I stared at this for quite a while pondering how I could coerce a flat steel sheet to take this form:



It was pretty obvious I couldn't make it in a single piece, but two pieces seemed achievable.
The raised pad for the rubber stop was formed in a press with a large socket under the sheet.

[festy]

The bead roller I got was a cheap chinese generic manual type, not all that rigid and this one doesn't even have grease nipples in the bearing blocks. I'll add them if I end up using the roller enough to worry about that.

My first attempt at forming a step turned out pretty well


But using a manual bead roller is not a one person job. It takes a fair amount of effort to crank the handle, and meanwhile you really need both hands at the other end to steer and guide the part through the rollers.

Its probably fine as long as you have a friend that can crank the handle for you - but that means I'd have to come up with an automated way of turning the crank handle  


Side quest time - powering the manual bead roller

I looked at how other people had powered their rollers - some used a big sprocket and chain on an electric motor, some used a garage door opener, or right angle reduction drives, 3 phase motors and VFDs... most costing way more than the roller itself.

What I needed was:
- variable speed (0-30ish rpm?)
- reversable direction
- lots of torque
- compact, or at least not too big and bulky
- foot control would be nice
- low voltage preferably
- cheap, as this was only a side quest after all

After considering a few options like big stepper motors or modifying a wiper motor, I found a decent sized gear reduction motor that I think was for an electric caravan awning.
The specs looked about right, and so did the price.

The motor bolted up nicely to a random thick steel bracket I found, so I took some measurements, 3D printed a shaft coupler, put it together and tried it out.
And immediately stripped the plastic coupler. Well, I guess the motor has plenty of torque
Try #2 - I made up a better coupler on the lathe and tried again, this time it worked much better.



I still needed to be able to control the direction and speed.
After scouring ebay I ended up with an electric scooter speed controller and a throttle pedal for an electric toy ATV.
Side quest completed for under $100   

[festy]

getting back to those bottom corners of the window frame, again this wasn't really going to work as a one piece patch


I made a very small, basic and dodgy bender out of a couple of bits of RHS and a pair of big door hinges - its vaguely useful, but that's the nicest thing I can say about it.
But seeing as there's really no straight edges or flat surfaces on these hatches, it was good enough for the few short bends I needed.

This part was made from 3 pieces: the top skin with a 90° bend forming the face facing the camera and the lip on the left hand side that folds over the frame edge; the bottom strip with a stepped lip; and the third piece to fill the inside corner.


Because the hatch is curved, there was lots of massaging needed to match this.

[festy]

Working at the blistering pace of completing roughly one patch repair per week, in only 3 or 4 short months my hatch was starting to look a bit healthier



The rear face still needed replacing, there wasn't really any salvageable metal so I thought I'd cut off what remained just below the top lip and replace it as a single piece.

It looked simple enough to start with, but that panel is anything but flat or straight edged.
The bottom edge is curved, the two side edges are angled inwards at the bottom, and the whole panel is lightly convex in both vertical and horizontal directions.

I made a template from my other gtv out of thin mdf then transferred that to sheet metal.
Next was hammer forming the slight curves, then an awful lot of smoothing out the hammer marks.

Using a tipping die in my bead roller I progressively bent a lip along the curved lower edge that would eventually be hammered down over the edge of the frame, and the same for forming the two side lips.

Then marked out and drilled the hole for the lock, and rolled the lip with a dimple die (i.e. a pair of suitably sized sockets and a press).
Then lots of trimming and fine adjustments, before tacking it into place for a final time then tacking it in between each weld, letting it cool down, and repeat until it was fully welded.



And that's roughly where I'm up to now, next comes filler and lots of sanding...

[NSharpley]

Just go fibreglass and perspex window.   Big weight save and no rust, ever!

You're doing some very nice metal work though.

[festy]

Just go fibreglass and perspex window.  Big weight save and no rust, ever!

That was/is my backup plan, but I would still need the hatch in a decent enough shape to take a mold from.
The weight saving isn't much of a concern to me though as I'm seriously thinking about turning it back into a road car anyway. Enough of a road car to pass a blue slip at least...

And my other gtv has rust in its hatch too, so I thought I should get some practice in first before tackling that one.
If this hatch actually turns out alright then I might swap them over temporarily so its not off the road for months while I repair the other hatch   

[Alfetta77]

Great work Festy, keep it up. Looking forward to having some time to learn those skills someday 

[poohbah]

Festy I am in total awe of your work. Need to get around to making a patch and welding it into the rear valance of my GTV. this will be my inspiration...

[festy]

Still slowly chipping away at this. The filling and sanding took far too long, and I regret not spending a bit more time getting the metal closer to its proper final shape because it probably would have been less effort in the end.

The first two coats of colour are on, I'm using 1997 ford laser 'classic red' because one of my GTVs is AR501 Rosso Alfa and the other is meant to be AR501 but has been repainted an orange-er red, possibly FER300 Rosso Corsa - and Ford Classic red is about halfway between the two.
And also because I had half a litre left over from repairing a laser a few years ago

[MD]

That will never fit. You have made it upside down 

[festy]

That will never fit. You have made it upside down 

No that's ok, I just need to flip it up the other way to make it fit.




Like this:

[MD]

AH, much better. An instant crowd pleaser. No need for an air foil either. Bonus.

[festy]

The paint has had 6 weeks to harden, time to see how it scrubs up.


Started with a very light (actually too light) colour sand, then cutting compound, then followed by a polish.
Then I realize I was too gentle with the colour sanding, so repeat the whole process.

It's a long way from perfect, but I'm happy enough with how its coming up.




Now, to find where I hid the rest of the chrome trim 10 years ago...