Sunday, August 7, 2011

Where did you go?

Into the shop, of course.

I will be posting pictures of the A3 Golf safety cage build up, and putting together a thread about Megasquirting the Jetta.

Right now, I'm having some issue controlling the fast idle circuit and need to dig in and see if there is some test software available so I can check the output at the before it wanders too far away from the I/O on the MCU.

My pressing projects finding me wishing I had an Oxy-Acetylene set, and an Oscilloscope. Yin and Yang?

Monday, May 30, 2011

Rally Minnesota- Jetta rental

Chad Eixenberger put the Bent Mettle Racing Jetta on the podium at the recent Rally Minnesota event held May 20-21 in Park Rapids, MN.  The event was marked by very wet road sections on the stunning, long stages.

For interested parties, we are making the car available for either a standalone rental, or can put together a complete arrive and drive package.

Chad will be campaigning the Jetta again next month at the Nemadji events and then taking delivery of a newly prepped 1995 VW GTI.

Sunday, April 17, 2011

Rally computer magnet mounting

The Jetta is equipped with a US made and supported Alfa Pro rally ( computer to measure time, speed, and distance.

The Alfa uses a switch to ground to trigger the pulse counter to measure distance- for cars with a VSS, it will interface directly, but on the Jetta, we used the included Hall effect probe and magnets.

The magnets were glued inside the rear left rotor, with the probe mounted off an ear from the rear stub axle fixing bolt.  This worked great until the rotor finally succombed 5 seasons of use and cracked.  In the rush to replace it, something went wrong with the magnet mounting leaving the unit unable to measure distance.

A Garmin Zumo GPS measuring speed and distance has been the extended temporary workaround for the past couple of seasons, but definitely wasn't optimized for rally use.

With the Jetta starting duty as a rental the rally computer made the list of "must fixes".

An email to Mike Friedman later, and I had a new probe and magnet kit sent out.  We are using the same basic layout for the probe, but with a removable ring mounted to the inside of the disc.

This only requires that the rotor be drilled and tapped to mount the ring.  The holes are easily layed out with a caliper, then drilled and tapped by hand from the front side.  The magnet mounting disk is reusable when the time to replace the rotors comes around again, which should prevent a repeat of the issues encountered last time.

Serviceable, durable, and done.

Friday, April 15, 2011

Small big lathe project

Over the course of the last 5 seasons, the bearing housings on the strut mounts have gotten pretty beat up.  With one cracked, it's time to make new ones.

This part starts off life as 4" diameter stock, and is stepped down to 2".  A 4" chunk of aluminum is reasonably hefty. This piece, 16" long, cost a cool $100.  With the relatively large diameter, the linear speed across the cutting tool is somewhat high, and will load up the machine if the depth is too great.

It sure does look pretty impressive sitting in the lathe, though.

For something of this size, the use of a live center while turning is a must.  The chuck jaws have been reversed, and the part is centered with a dial indicator prior to center drilling.

Then it's just a matter of whittling away- it's going to take about 65 passes. Yikes!


No pictures of the boring steps, but eventually the housing made it's way to the mill for holes and getting squared up.

The DRO speeds up punching holes in the part, as well as the milling operations. Rather than spin in the part center with a indicator, an onsize plug for the bore was turned center drilled.  A center drill in the mill to pick up the center gets within .004" or so of center.  For this part, that's accurate enough for the remaining operations, and significantly faster.

The balance between time and cost comes down to knowing required tolerances for a piece part, as well as the assembled part.

Monday, April 11, 2011

Bending stiffness- door bars

Multiple tubes in the same plane are required to prevent side intrusion. The builder is left with several options as to tubing diameter and wall thickness. This spreadsheet compares idealized properties of the tubes to give an idea of how adding extra elements would affect weight of the assembly, or overall bending stiffness. (Stiffness largely drives energy absorption unless the tubes buckle or otherwise plastically deform)

Number of Tubes

constant OD (inches) thickness I 1 2 3
Relative mass per unit length
Stiffness to mass ratio

0.04900 1.50000 0.095 0.10376 0.1038 0.2075 0.3113

0.04900 1.50000 0.120 0.12456 0.1246 0.2491 0.3737

0.04900 1.75000 0.095 0.16937 0.1694 0.3387 0.5081

0.04900 1.75000 0.120 0.20482 0.2048 0.4096 0.6145

0.04900 2.00000 0.083 0.22964 0.2296 0.4593 0.6889

Friday, April 8, 2011

Steering stops

It's difficult for privateer competitors to fully develop their vehicles in a vacuum. Even after years of active use, I find myself poking through some of the parts manuals that Volkswagen had provided for both their 2nd and 3rd generation Golf platforms.

Both prep manuals show spacers on the steering rack, and after incorrectly implementing them, I've realized they're primarily there to limit steering rack travel.

Evidence of tire contact on the transmission and/or brake lines in the wheel well sometimes appears, but I hadn't connected the two until this weekend while replacing the steering rack.

If you have bare spots where your tires have been rubbing inside your wheel wells, some spacers will prevent that, as well as take a bit of strain off your CVs.

Contact me for more information on the where/what/how of installation...

Tuesday, March 15, 2011

The New Jetta enters the garage

Matt just told me that the new Jetta roller has made it into the garage.  He says he has plans to make it into a rally car too.  Then he can rent one out for races or wear them both as roller skates when he's operating his robot megasuit.

This car is alot like the other Jetta except that it's not five different cars welded together.  The new Jetta is just two different cars and they are  bolted together instead, so that part is much different.

I assume that there is alot of planning that goes into the construction of a rally car.  I bet Matt has been having some serious discussions with his team of development engineers on how to maximize important rally car vehicle attributes like body strength, low vehicle weight and roof cargo capacity.

My proposed design addresses each of these.  To shield against unplanned excursions into the woods the Jetta will be covered with 22 impenetrable panels fashioned from Brazilian teak.   The overhead cargo rack can carry 200 kilos of spare parts, camping gear and serendipitous roadkill finds.  Installing three aft mounted louvered intake fins will funnel massive volumes of air into the trunk thus making the back end of the car lighter at high speeds.   I am still working on equally innovative ideas to lighten the front end.  Feel free to comment and let me know if you have any bright ideas.

The New Jetta coming to a rally special stage soon- shown with versatile Kid-Cam® in-car video system.

Tuesday, March 1, 2011

100 Acre Wood G2 Regional Recap

The 2011 Rally America Central Region Group 2 points race tightened up again this weekend with three competitors swapping times- and podium spots during the 2 day event in Salem, MO.

Day 1- Trespassers Wil Regional Rally
The Trespassers Wil event started with less than half a second separating Chris Greenhouse, Billy Mann, and Matt Bushore on the rutted mud of the Potosi Lions Club stage, with each driver sneaking in under the minute mark for the stage.

Greenhouse and co-driver Brian Johnson found their pace quickly on the fast and smooth roads that make up the specialstages of the Ozark Mountains, opening up an 8 second lead over Bushore and brother Andrew Bushore, and besting Mann and co-driver Don Burress by 22 seconds over the 10 mile stage with a stage time of 9:21.3

Greenhouse found another 2 seconds on the second running of the crater pocked Superspecial, with Mann slipping back another 4 seconds against the class leader in the second outing of his newly completed Honda Civic.

A delay as stage crews worked to move the mangled shell of Travis Pastrana's STI left the teams concerned about their lack of driving lights, however, the stage opened for competition just as twilight was falling. Billy Mann continued to build pace on this running, with both Bushore and Greenhouse falling off their previous marks, with Greenhouse edging Bushore by under 2 seconds.

Knowing that the 11 second gap would be difficult to close, Bushore had even more work ahead with the cancellation of SS5 due to flood waters on the transit, leaving only SS6 to try to close the gap to first place. Mann, comfortably in 3rd place with a 2 minute gap over the 4th place team of Ian Topping and Jeff Secor, stood to benefit from any mistakes made by pushing on the final stage of the evening with only a 20 second gap to 2nd place.

The final stage of the evening started significantly tighter than the previous stages before opening up to finish fast over numerous jumps, requiring a change in pace and driving style that left the Bushore team struggling, while Greenhouse adapted quickly, securing the stage win, and ultimately, first place in class for the day. Mann completed the stage briskly, earning a 3rd place podium spot.

Day 2- 100 Acre Wood Regional Rally
The scheduled 80 stage miles of day two's 100 Acre Wood regional rally met the competitors early with a Parc Expose in downtown Salem. Following the restart, Bushore was scheduled to follow Greenhouse on the road, with Mann separated by only a few cars.

The 10.85 mile Southern Loop opened the event with an abundance of water crossings, leaving several teams to struggle with rough running engines leaving the deep low water bridge 4 miles from the stage finish. An aggressive approach to the water with a car proven to handle deep water better than most put Bushore up 10 seconds over Greenhouse, with Mann nearly 35 seconds off the class winning stage time.

The second running of the Southern Loop was pulled due to an incident with the team of Lagermann and Beavis; the announcement to hold came over the radio with only 10 seconds remaining before the stage start for Bushore, Greenhouse having left one minute earlier. All teams would receive the same time for the stage.

Using the 7.3 mile SS9 to exact his revenge, Greenhouse won the stage, beating Bushore by 6 seconds and Mann by over 25 seconds, and closing his gap to first place to a mere 4 seconds.

Greenhouse gained another second in his first place quest on the third running of the Superspecial, but Billy Mann struck back on the third running of the Floyd Tower roads of SS11, besting both Bushore and Greenhouse, and winning the extraordinarily fast stage with a 9:23.

Mann again clawed back with a 5 second margin on the SS12 class win, while the trio finished the short sprint through SS13 with a margin of less than 2 seconds between Bushore, Greenhouse and Mann.

The gap between first and second remained at a mere 9 seconds with 3 competitive stages left in the evening.

That gap increased to almost 14 seconds after SS14- another long, faster 10.45 mile stage that saw the Volkswagen edge out the Neon by less than 1 second per mile.

SS15, a short twisty 4.2 miler would see the door start to close on Greenhouse's hopes for another first place in the regional as Bushore gained another 7 seconds, with Bill Mann scoring a 2nd in class on the stage.

The event closing 10.1 mile stage would prove another tight race- with less than 5 seconds separating the winning stage time from 3rd place- but not without drama.

A noting error on the final corner of the last stage almost led to total destruction when Co-driver Andrew Bushore called the medium turn before the flying finish as one to enter full throttle. The Jetta narrowly missed a row of trees on the side of the road, leaving the team shaken on the transit back to Salem to discover they had won the days contest, as well as the inaugural Honey Jar Challenge.

Billy Mann picked up 3rd in class for the second time in the weekend, moving him into 3rd in the points race with 132 points. Matt Bushore, placing first in the C3 event, saw a big jump to 216 points and 2nd place after the weekend, with Chris Greenhouse narrowly retaining his leading points position at 235 points.

Monday, February 14, 2011

This Chery is a Peach

I talked Detroit Hooligan and man about town Steve Brock into getting his Lemons/Chumpcar dumped off at my house.

It's a Chery Windcloud, which is a Chinese domestic market licensed copy of a Seat Toledo, which is based on the VW MK2.  Which means it's made of really thin mental, but all sorts of VW parts bolt into it.  The car was in the states for some drivetrain development, found it's way to a junkyard, and then into my garage.

Steve and friends picked up a cage kit from SW Racecars which mostly fits.  The A pillar tubes stop where the dash would be, so it's not going to be really comfortable getting in and out of.

The rest fits well, and is reasonably tight to the roof. Some photos of the cage welded to the pads, and dropped through the floor getting the topside welded up...

Saturday, February 12, 2011

Honda Steering Quickener

Billy Mann and Paul Eddleston stopped by today to pick up some used tires and get some machine work done on Billy's steering column.

Billy did the work on the bracket, but needed the Honda parts grafted onto the quickener shaft.

I turned some stepped shafts to locate everything co-axially, then used the TIG welder to fuse the shafts together.

The input side was clean metal that handles the welding well- using stainless filler rod leaf a cosmetically pleasing bead that won't rust, either.

I'll have to have Billy send me photos of the installed part to see how it all finally fits up.

Saturday, February 5, 2011

Sno*Drift Recap

Our first Sno*Drift in 2005 was probably a bona-fide disaster.  We hit a stump the first night, tearing off a control arm, bending a strut, and destroying a halfshaft.  The several mile ride out of the woods bouncing along the skid plate was "interesting".

The next day, we proceeded to slid into a snowbank and re-wreck that same corner of the car, along with the borrowed halfshaft.

Six years later finds both of us far more experienced, a bit jaded, and more focused on regular sleep than extreme driving. The event previous, LSPR, was uneventful in nearly all aspects, leaving minimal carnage to take care of on the car.

With the luxury of time on my hands, I swapped to softer springs for the snow event- the logic being that a lower friction surface won't generate the lateral force that a surface like gravel does, and with the lower forces involved, a higher spring rate on the suspension doesn't allow things to move like they should.

We also opted to try a Note Familiarization Pass aka (somewhat incorrectly) as Recce.  This has been available to US competitors for a couple of years now, but requires an extra day at the event.  With no worries about vacation time, trying it here was nearly a no brainer.  Spending all day pre-driving the course at moderate speeds was mind-numbing.  At the time, I had little positive to say about the experience, although in retrospect, Andrew suggested he felt far more confident in the notes, and was able to try to push the pace from his seat for the first time.

While we were out on Recce, our father Barney, and brother Marc lumbered up to the event with the Van, rally car riding comfortably on the trailer.

They managed to successfully register, get the car through scruitineering, and find the nearest public house.  We joined them after Recce for a carbonated beverage, and retired to the hotel to await the arrival of our hired guns, Erik and Kenny.

The addition of 4 more people into the room made it painfully obvious that we were now well above capacity.  Kenny jockeyed for the coveted floor spot while Erik made his nest perched upon a series of chairs set next to each other.  It looked uncomfortable, bordering on torturous, despite his claims of absolute comfort and total bliss.

Our first leg out of Lewiston was unremarkable.  Sno*Drift rewards those who stay on the road.  We ran a brisk but steady pace, and kept our (and the cars) noses clean.  We were rewarded with a 2nd in class spot in the regional event going into the first service.

Things became more interesting in service.  The cold weather conspired with some dodgy crimp connectors to render the light pod connectorless. We tossed it into the trunk, along with some tools, and anxiously sat through the RGC with the plan to fix the wiring during the fuel depot stop immediately after the RGC.

While we were chewing our frozen fingernails,we noticed that Chris Greenhouse hadn't checked into the RGC with us as expected.  When he finally did, he was facing a time penalty over 2 minutes for the lateness incurred to get a balkly alternator belt back onto the car.

We'd been running neck and neck all day and this placed us firmly into the number one spot in the G2 regional.  We just needed lights.

While the crew fueled the car, I used butt connectors to repair the pod wiring.  After fueling, Andrew was to pull the car around near me to install the lights.  This went like clock work, and we set off onto the transit.

6 miles out of town, the front end began shaking, and it became obvious something was very wrong with the car.  That something wrong was a flat tire that Andrew is convinced was caused by his striking a curb while driving it into the parking lot.  A rapid tire change left us with mis-matched front tires, a lost wallet, and the need to adhere to the upper end of the speed limit to ensure we'd get to the next control on time.

No one likes to arrive at an ATC in the middle of their minute; any road blockage would have let to lateness.

Running the next few stages on two different sized front tires was annoying, but workable. We had a sizeable lead in our class, and were able to maintain our pace.

On the final stage of the evening, we passed a stopped Chris Duplessis, which we immediately recognized as leaving us in 2nd place in the Thayer Automotive Sno*Attack 2WD Challenge for the weekend, sitting right behind Dillon Van Way.  Within minutes, the feeling of elation was one of exhaustion as we attempted to extract our car off a small snow bank at the bottom of a medium right hand turn I'd mis-navigated.

A failed rescue attempt by Matt Marker left us with no tow rope, and sunken spirits as car after car passed.  Finally, Chris Greenhouse, who had started behind us due to his service issues, stopped and yanked us out.  By catching us, he was securely back into the class leading position, and being the true sportsman, he wanted to ensure we'd get going again.

The conclusion of the stage was uneventful, with plenty of time to stew on What-Ifs.  Our final obstacle of the evening was to find my wallet that had dropped out of the car at some point.  After driving to the pullout where we'd changed the tire, Andrew found my wallet, and we headed back towards Atlanta, exhausted, and 10 minutes down to other competitors.

We finished the Sno regional event well down in class to newer competitors who had cleaner runs, and well out of the money in the Sno*Attack event.  Still, the car was in good shape, running well, and mostly needed the tires juggled around.

Marc led Erik and Kenny through the evening service routine while Andrew and I tried to decompress and prepare for the early Saturday morning that was rapidly approaching.


Sunday, January 16, 2011

Figured this year was as good as an to get rid of the old unsupported content management system and delve deeper into the dark soul of the Googlempire.