Nocones $2020 challenge build thread

In reply to nocones :

The fiddle brakes seem to have the same requirement as a real fiddle..need to practice enough to play the thing. I cant see developing the muscle memory where I could use them instinctively.

Base frame is welded.  I forgot how long it takes to prep tube ends and weld.  It was 2 hours of work and all the tubes were fit and ready to go other then cleaning the ends.  Next step is the roll bar plates.

Nice welds!

Alfa Romeo made a lot of 5 on the tree cars in the 1960s/70s. They were not simple linkages though

In reply to TurnerX19 :

I just looked that up.  I was not aware of the 5 on the tree.  That's amazing.  I'm thinking mine will have the 1-2 shift be forward/backward with rotation being select vs the way those work.  So mine really is just anchoring a normal shifter on the column.

No physical progress but Episode 4 is up.  On this one I fab the seat mockup, and bend the main hoop.  That puts the videos about 3 work nights behind.  I'm unlikely to keep up the 1/wk videos but for now it's what's working.

Got a few hours to work this afternoon.  Base plates are done ready to be welded in.  I got to use CAD which is the best process ever.  

Question, should I drill them to plug weld them to the top of the chassis tube?  I'm going to weld all around them but not sure If there is anything to be gained plug welding them in the flat plate area.  

Tube / Metal used is now

4130 - 161.5"@ 6.50/ft = $120.79

2x2 - 267-3/8" @ 1.67/ft = $37.21

4130 Plate - 0.61 sq-ft @ $11.00/sq-ft = 6.70

Total = $164.70

In reply to nocones :

 That's amazing.  I'm thinking mine will have the 1-2 shift be forward/backward with rotation being select vs the way those work The exact opposite of what happens when you take a 4 on the tree Panhard and convert to a 4 on the floor D.B.! 1-2 is side to side in a D.B.2-3 is left a little, back a little, and more left. People won races with them, so why not???

I <3 the CAD method. I find cereal boxes to be perfect for most situations. I wouldn't both plugging the plates. 

I don't know why but I have the hardest time trying to cast your videos to my TV.  Might just be me.

I decided to not plug weld the plates.  They will be perimeter welded to the corner of the 2*2 tube.  

Also I was excited because I mostly remembered how to TIG weld.

I only had time to do 2 of the plates.  I didn't want to rush to weld the other two. 

Also I've switched basically full time back to the old school always on weld helmet.  Everytime I weld with an autodark the sensor gets obscured or the battery dies and I end up getting full arcy sparky to the faceball which seems sub par.   I've got two a cheapo and a Hobart and they both let me down.  

re: seats

I'd probably go with having a "pan" of sorts.  iirc, DPcars does.  One of the benefits of that, even in if you do an 'foam insert' thing, is that you don't need as much foam.  So the whole thing ends up lighter.  Maybe cheaper too?

I used to have a Harbor Fright auto-blinding helmet.  That thing was headache-city.

I bought a good ($200) Miller helmet and I can use it all day.  I've not even replaced the batteries in about 4 years of regular use.

I think some of the fancier helmets have sensors at the top and bottom of the viewing window so you're much less likely to block all of them.

Yeah the issue definitely seems to be with blocking the sensor.  I'll look at a different new helmet to see if I want to try another.  For now I am using a permadark for anything compromised and the autodark for tabletop work.

Got some more welding done.  Now all 4 plates are welded and the cage is TIG tacked back together.  Basically I'm back where I was but now nothing has to come out again. 

Next up is windshield bars and door bars. 

Looking good!

Not technically related, but your build came to mind when I saw it.

In reply to AWSX1686 (Forum Supporter) :

I've seen that one before.  And also the 32 ford F1 car.  I think that they all are cool, I just wish you saw more of them tearing up the track and less hard parked in someone's garage.

Upper (29.75") and lower (39") windshield bars are in.  Onward towards side bars. 

Tube / Metal used is now

4130 - 291.75"@ 6.50/ft = $158.03

2x2 - 267-3/8" @ 1.67/ft = $37.21

4130 Plate - 0.61 sq-ft @ $11.00/sq-ft = 6.70

Total = $201.94

I bent up a side impact tube.  I tried to avoid notching the door.  It fits ok, and gives more space for exit but I don't like how exposed your shoulder would be.  The harness bar is the top tape band.

I think I'm going to remake it and go ahead and notch the door post.  It will raise the bar almost 5" and still be able to have most of the extra space for entry.  

I motion that the phrase "I didn't want to cut..." be henceforth banned from this thread. 
Violators shall have to make penance by doing more extra awesome fabrication work for our viewing pleasure. 

In reply to barefootskater (Shaun) :

When you say it like that and looking at the pictures the fact that I want to try not to cut anything seems ridiculous..  I guess it's Grinder time

Since this has an open roof currently, shouldn't you make ingress/egress out the top? Need to maintain some side access in the event of inverted run conclusion, but that would be the emergency in my view. Remember that current GT rules now require top hatches for emergency use.

Yes the plan is to leave the top available for a hatch.  The stock roof was black vinyl covered fiberglass and some were removable fabric.   I'm probably going to use a similar design for the roof of this.  I like the idea of using/leaving functional doors of some kind.   Either way I want to be able to enter and exit through the door/window openings. 

My current brain noodle is if I need rear windows or if I can have a solid firewall behind the driver (Ala LMP type cars).  NASA and SCCA both don't really talk about rear windows much in the specs.   Prototype cars don't have them but are specifically homologated.   The rule books aren't really designed around turing a Subaru 360 into a Prototype...   

I re-reviewed the 3 major cage specs (NHRA, NASA, & SCCA) and I think the following design is the only one that will meet the letter of all 3.  

NHRA says little about the side bars but that either a X or a bar from shoulder to bottom of the front tube is acceptable (No specific allowance for FIA type X bars or NASCAR bars which are a top bar and a bottom bar).

There will be a single plane bow in this bar to give more space.  

I don't like that this style really relies on 1 tube in an impact (Through the center of the X).  I plan to post challenge add additional tubes (Or formed plate gussets) as shown in the dark black lines.  This will increase the load bearing across the X as well as improve coverage of the driver for impacts.   These will be a post Challenge mod as the cost to make them is about $20/side for either tube or gusset sheet. 

So time to grind out some door frames and bend another tube.   

FIA style X-bars are my favorite too and I used that style on the Ranger. Mine are not gusseted as the truck does not see w2w action or even track days so far...
It is a shame the NHRA rulebook spends more time delineating how to gusset an incomplete weld joint than it does on proper door bar construction. I see no reason an FIA style X should fail tech, but as you stated there is no specific allowance for it

X cross bar looks good. Version #1 doesn't look like it picks up your main hoop within 5" of the driver's shoulder, which, from memory, is mandatory (NHRA). Dumbfoundingly great work. 

On an somewhat unrelated note, your string model video was an absolute epiphany for me. I've been screwing with them for years and struggling. The problem was I wasn't starting with roll center, I was trying to work towards it from the control arms. Your way makes it look incredibly easy. The education is much appreciated.