"the next one" - Scratchbuilt Mid-Engine Sports Car

[invision]

Mar 12, 2014 17:01:43 GMT remmoc said:

Another interior , are you not happy with this one or are you like me and had another better idea half way through ?

A little from column A and a little from column B.

The first one looked a bit simple... you'll see what I mean when I post progress of the second one

[DWDarkWheels]

Still looking visionary, Invision

Got any pics from away-back so we can see how the car as a whole is coming together?

[invision]

Mar 14, 2014 19:55:59 GMT DWDarkWheels said:

Still looking visionary, Invision

Got any pics from away-back so we can see how the car as a whole is coming together?

Not much to see yet at this stage, but I'm working up to it. Once body panel assemblies have been welded together and mounted you'll get a better idea.

On another note, I've had a few questions in regards to the roadster and how we start off a project. While I'm not going to include it's build in this thread, here a couple of photos of the ride's humble beginnings.

  

Now back to our regular programming. 

[invision]

Well, after a little hiatus into the world of composite panel fabrication, it's time to get back into some metal work.

The last time we left off, I was in the process of shaping the exterior pieces/panels. The time has now come to start joining those pieces together creating body sub assemblies.

Work begins to weld up the front fascia. While it's a tedious process, this is where things start to shape up...no pun intended.


Grinding down the weld proud.


Time to flip things over. Prepping and tacking the pieces together for the bottom front fascia. Final welds will be about 2" at a time with no less than 30 welds.


I don't rush the process. Once the panel is welded it's allowed to cool down until I can touch any area by hand. Then the grinding begins.


First pass of grinding down the weld's pride.


Second pass...


My brother-in-law dropped by the shop while I was working on the front sub assembly and wanted to help out. Prior to this he never shaped metal nor welded before. It was a perfect opportunity for him to jump in with both feet and fabricate the fascia's bottom corners. After showing him how to use the Shrinker/Stretcher and English Wheel I set him up with some cardboard to create a template. He then transposed this to a piece of sheet metal and started shaping it to the appropriate curve.


Then the real fun began. He was to weld these pieces into the corner areas. He scribed the pieces, trimmed them and carefully tacked them into place.




Steve grinds down the tacks in preparation to planish them.




While planishing, Steve learned how to control the sheet metal around the tack to create a seamless butt joint. His next task was to weld up the joint...not too bad for his first time. Good penetration...just that pride was a bit high...meaning more time and material(grinding disks) to clean it up.


Unfortunately, we didn't get any photos of the bottom fascia ground and finished up. Will try to remember to get a shot next time I'm working on the car.

[mayoturbo]

Awesome work and great skills. Will keep checking your threads! Is there any reason why you use a MIG welder over a TIG?

[invision]

Mar 22, 2014 17:51:57 GMT mayoturbo said:

Awesome work and great skills. Will keep checking your threads! Is there any reason why you use a MIG welder over a TIG?

No particular reason. We have both. One can move much faster with a MIG than a TIG. The biggest thing when MIG welding is to run HOT and quick...otherwise you end up with a high proud requiring more work to clean up... like in the last photo. This was his first attempt, so having learned what not to do and how it feels to weld sheet metal, he'll improve.

Thanks very much!

[Robinxr4i]

How have I missed this? Brain melting fabrication skills and vision, truly inspirational.

[DMS]

Feb 4, 2014 13:17:54 GMT invision said:

Hi DMS!  I can do one better. Here's a step by step on making one.

Doesn't take long ...bout 25 minutes...and you can create a surface profile that meets your requirements. Usually, flatter is better...but not too flat. Spreads the impact's contact face over a larger area resulting in averaging out convolutions in the metal.

Rough outline of the overall general shape on a truck's leaf spring.

I didn't get around untill now to say thanks: "Thanks!"

It sure is helpfull.

One questions though. Is it necessary to for the metal to be of spring leaf material. It's a bit hard for me to source around here.

[invision]

Mar 25, 2014 14:41:44 GMT DMS said:

Feb 4, 2014 13:17:54 GMT invision said:

Hi DMS!  I can do one better. Here's a step by step on making one.

Doesn't take long ...bout 25 minutes...and you can create a surface profile that meets your requirements. Usually, flatter is better...but not too flat. Spreads the impact's contact face over a larger area resulting in averaging out convolutions in the metal.

Rough outline of the overall general shape on a truck's leaf spring.

I didn't get around untill now to say thanks: "Thanks!"

It sure is helpfull.

One questions though. Is it necessary to for the metal to be of spring leaf material. It's a bit hard for me to source around here.

You can get by with mild steel if you're in a pinch. However, it'll begin to peen rather quickly and any imperfections in the metal's surface will marr the face your slapper. The harder the steel the better.

At times I'll turn my slapper on edge and strike it with another hammer to clean up a feature... Well, this has caused that top edge to peen and I'm using spring material already.

[invision]

The beginnings of a new...hood. Yeap...you read that correctly. I didn't like the features on the first one so we're redoing it. After the fresh sheet metal pieces were cut out based on original templates, a little more 'bump' was rolled into them with the wheel.




Once the overall curvature was established in the main area a reverse curve was created using one of the sharper lower anvil and carefully rolling the trough's edges until the panel started to relax upwards


With the pieces formed… fitting begins.


Slowly starting to look like a hood. Condensation is a strange thing…soon as we opened the shop doors that particular afternoon a small patch of surface rust appeared on the centre panel. No worries as the DA will take care of that.


A little tuck shrinking to deal with the flange’s excess length. The metal will actually get hammered into itself.


Almost there…a little more work and we’ll have a nice smooth curve.


Side flanges bent and pieces finally fit to each other. Next step… tacking!




Panels lined up and ready for welding.


During the tacking process panels are constantly tweaked in order to ensure a nice smooth curvature.


With each tack the hood is getting to sound…right. After the tacks have been completed and hood cools off grinding can begin.


First pass at grinding the welds.


After some more grinding out comes the flat file to reveal the highs and lows. However minor these areas may be they need to be addressed.


Working with the hammers, spoons and dollies... highs and lows are normalized until you get a smooth consistent surface.

[dw1603]

Following your thread, it would be easy to believe that you had spent a lifetime as a coach builder, or maybe worked in a prototype shop. To realise that you are self taught is astounding. You must be quite a teacher too, judging by your brother in law's first attempts at metal shaping and welding. I have tried both skills and I mostly produce scrap metal. Very impressed.

[invision]

Thanks very much dw1603! It's all a matter of mileage. I just keep working away at something till I'm pleased with the results.

[varelse]

This build is amazing! Your skills are incredible!
It's really cool to watch the car forming up in to a more complete picture.

[invision]

Thanks varelse.

[invision]

Hi everyone!

Here's another installment on R2's build journey. With the hood skin more or less finished, it was time to re-create the front moisture trough. I wasn't happy with the way the sides looked the first time I made them.. too narrow.


On the second version, you'll see that it has more continuity. With only a few tacks and self-drilling/self-tapping screws holding the front compartment surround together it's taken out and work begins to make things a little more permanent.


Working the area towards an invisible butt joint.


Where strength is required joints are overlapped and plug-welded.


Can never seem to have enough clamps. Need to ensure panels are mated with no gaps for a uniform weld distribution.


All done and ready to be installed later...


Thanks for checking out the progress.

[invision]

Some work done on the front inner fenders...

While they were mounted inside the buck witness marks were created and self drilling-self tapping screws used to temporary fasten the two pieces together.


Exterior piece gets a reveal created for additional strength as well as a seat for the the inner piece to sit in.


Some additional trimming and hammer/dollie work along the edges was required for a nice tight fit.


Assembled, welded and cleaned up with a flap disk...the piece is ready to be reinstalled.


Finishing up the front fenders.


The two pieces were fit and tacked together earlier on the buck. Now it's time to complete the joint.


Grinding off the proud... taking it slow so as not to build up too much heat.




Very close to an invisible joint. After going over the area with a file followed by a DA loaded with 80grit only few small flaws remain. These will still require a few more minutes to planish and clean up.

[invision]

The exterior skin is only as good as the structure used to support it. Working on the inner rockers that will basically connect the front and rear of the vehicle together.

After the box section were bent holes were created for plug welds.


As the pieces are being welded together the flanges are tapped down ensuring a tight fit.


...a good peak of an an arc flash.


Have a great day everyone!

[eurogranada]

Amazing as ever!

[DWDarkWheels]

My vocabulary is too limited to do justice to this. Just checking in for more awesomeness.

[kev13s]

That is a truly epic undertaking, what I wouldn't give for a quarter of you're ability.