2012 AARCMCC EP10 OFR NATIONAL CHAMPIONSHIPS - April 4 - 9
03-27-2012, 08:08 AM
#511
Hey guys,
with the massive entry list and the run times we now get with Lipos, is there any plan for controlling practice on Wednesday if the lines get huge? With 2 cars and a pitman you can easily stay out on the track for 30 minutes now
cant wait for next weekend!
Ray
with the massive entry list and the run times we now get with Lipos, is there any plan for controlling practice on Wednesday if the lines get huge? With 2 cars and a pitman you can easily stay out on the track for 30 minutes now
cant wait for next weekend!
Ray
03-27-2012, 02:27 PM
#513
Hey guys,
with the massive entry list and the run times we now get with Lipos, is there any plan for controlling practice on Wednesday if the lines get huge? With 2 cars and a pitman you can easily stay out on the track for 30 minutes now
cant wait for next weekend!
Ray
with the massive entry list and the run times we now get with Lipos, is there any plan for controlling practice on Wednesday if the lines get huge? With 2 cars and a pitman you can easily stay out on the track for 30 minutes now
cant wait for next weekend!
Ray
As it is now in timed practice on Thursday we are looking at 3 x 7 minutes per car for the day and this is with heats of up to 12 drivers and a 1 minute turn around between heats. This is for the sanctioned classes only with Shortcourse to get 2 x 30 minute sessions for 53 drivers.
Any feedback or suggestions welcome.
03-27-2012, 04:28 PM
#515
I can't see a problem with extending practice on Wednesday. Maybe 30minutes earlier and later (I'll check with the track guys and see if this is enough time to get things sorted).
As stated I'm sure if your on the stand for too long you will be dragged down the stairs by an angry mob.
03-27-2012, 07:27 PM
#517
I agree Ray but it's hard to police in a free practice format especially not knowing who will be turning up on Wednesday.
As it is now in timed practice on Thursday we are looking at 3 x 7 minutes per car for the day and this is with heats of up to 12 drivers and a 1 minute turn around between heats. This is for the sanctioned classes only with Shortcourse to get 2 x 30 minute sessions for 53 drivers.
Any feedback or suggestions welcome.
As it is now in timed practice on Thursday we are looking at 3 x 7 minutes per car for the day and this is with heats of up to 12 drivers and a 1 minute turn around between heats. This is for the sanctioned classes only with Shortcourse to get 2 x 30 minute sessions for 53 drivers.
Any feedback or suggestions welcome.
Just get a clock, white board and a marker. Draw a table with a slot for every space on the stand. When a driver goes up, they write their name and the time in one slot. After say 10 minutes, anyone waiting in line will be able to yell up to the stand that so and so's time is up.
It's low tech and self policing.
03-27-2012, 08:16 PM
#518
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If I may be serious for a moment. At the practice meeting there was a cell size checking box, and many competitors had trouble squeezing their cells into it. I was one of those people. None of my cells fitted (in fact all my packs are saddles and none of the halves fitted) even though the manufacturer gives their nominal height as 25.1 mm. I'm confident the battery dimensions (unlike the car dimensions) in our rules have always been nominal dimensions (i.e. as specified by the manufacturer)*, however I have taken my cells home and experimented with what to do to get them to fit.
I'm posting the information below as it may be useful to others.
A pack I had 80% charged measured 26.15 mm, others were similar. After discharging a couple down to 6V they were all more than half a mm thinner. Putting the pack in the fridge (not freezer - artificially cooling packs is not allowed, so there is no point simulating anything below ambient on a cold morning) also helped a little bit.
After taking some careful measurements I find that the stickers on either side of the battery are a little over 0.10 mm each. Hopefully we are not going to be asked to remove the stickers as this will make them impossible to verify as ROAR/BRCA approved at meetings in the future.
The batteries I tested were predominantly IP 5200s. I also have some IP 5400s that are brand new never been touched since their arrival. Their nominal dimension is 25.1 mm (http://www.ip-battery.com/epro_show....=pro&id=13&p=1) – the maximum in the rules. At the edges of the packs the height is 24.9 mm. In the centre the pack is just legal if I take the labels into account and depending on how tight I hold the verniers. I haven't tried discharging them further yet.
Someone suggested a vice to me. I don't have one, and I don't particularly think it is a good idea to try and crush a cell into dimension, and I don't want to see anyone else try it either.
At the World Championships, the only other place to my knowledge where cell checking of this type has been carried out, those using packs with chassis positioning nodules had to grind those off, voiding the warranty. Since then the IFMAR wording has changed to include this phrase "Chassis location features additional to this dimension are allowed" with regard to the height. I think Gavin indicated that packs with these types of nodules could be measured across another part of the pack (correct me if I'm wrong), so don't go grinding bits off is what I'm trying to say.
* Previous rule book editions always used the word nominal when talking about cell dimensions (NiCd and NiMH). The current dimensions in our rule book are the same as ROAR (and IFMAR). However, ROAR specify them as 'case dimensions' rather than battery dimensions, i.e. the undistorted dimensions of the case. The IFMAR rules now also indicate case rather than battery sizes.
Our rules are written so that the dimensions and the ROAR/BRCA approval applies. ROAR previously had cells "grandfathered" into the regulations. That is they were outside the nominal dimensions by quite a bit but were still ROAR approved. Recently these were taken off the list so I believe everything on either list should meet the nominal dimensions specified in our rule set.
Last edited by Radio Active; 03-27-2012 at 08:38 PM.
03-27-2012, 10:24 PM
#522
The battery box is totally dumb. Either a pack is approved, or not.
If it's to prevent 'dangerous' puffing of cells, then it should be based on a percentage. I could have a 3800 pack that's crazy puffed, but since it fits in the box, it's fine to use.
I hope some common sense prevails on this at the Nats.
Cheers,
Scotty P.
If it's to prevent 'dangerous' puffing of cells, then it should be based on a percentage. I could have a 3800 pack that's crazy puffed, but since it fits in the box, it's fine to use.
I hope some common sense prevails on this at the Nats.
Cheers,
Scotty P.
03-27-2012, 10:28 PM
#523
There would have been a need when there were packs out of dimension grandfathered in. I had some of those and they didn't fit in my car. I had to sell them again at a loss.
The pack dimensions are in the rules so chassis manufacturers (and scratch builders) can build their car and have the packs fit.
I agree those are odd, and they don't appear in the ROAR or IFMAR rules.
A negative tolerance on a maximum dimension is completely meaningless.
The positive tolerance listed in all cases is 0 mm. Except when it comes to width, then the reg reads "0mm-2mm". This could be a typo but any student of grammar will tell you that means 0 to 2 mm. This would mean the pack could be 2 mm wider than the dimension listed.
The pack dimensions are in the rules so chassis manufacturers (and scratch builders) can build their car and have the packs fit.
A negative tolerance on a maximum dimension is completely meaningless.
The positive tolerance listed in all cases is 0 mm. Except when it comes to width, then the reg reads "0mm-2mm". This could be a typo but any student of grammar will tell you that means 0 to 2 mm. This would mean the pack could be 2 mm wider than the dimension listed.
03-27-2012, 10:44 PM
#524
The St Ives club will be guided by AARCMCC on the battery situation. At this point in time we have been advised that batteries will be checked pre meeting and if they do not slide into box they will not be allowed to be used at the meeting. I'm not saying I agree with the rules but this is an AARCMCC sanctioned event so we (the club) are bound by the rules set out by AARCMCC.
While were at it what is the reason for AARCMCC rules setting the tyre limit to 6 sets per class? Am I missing something? If you make the A final you will have 7 races so I don't see it as a money saving rule as I don't think another $30 spent at a National event is going to stop anyone attending. All it does is add another thing that has to be scrutineered.
While were at it what is the reason for AARCMCC rules setting the tyre limit to 6 sets per class? Am I missing something? If you make the A final you will have 7 races so I don't see it as a money saving rule as I don't think another $30 spent at a National event is going to stop anyone attending. All it does is add another thing that has to be scrutineered.
Last edited by mharlow; 03-28-2012 at 12:25 AM.
03-27-2012, 11:01 PM
#525
On another note why do the AARCMCC rules limit tyres to 6 sets per class? If you make the A final you will have 7 races so I don't see it as a money saving rule as I don't think another $30 spent at a National event is going to stop anyone attending. All it does is add another thing that has to be scrutineered.
Originally Posted by AARCMCC EP OFR Rules, Jan 2011
9.5 Control Tyres
9.5.1 Tyre type: Rubber only with foam inserts.
9.5.2 Control tyres must be used for all classes.
9.5.3 Specified control tyres must be fitted on the correct axle.
9.5.4 All tyres must be black. Foam tyres are not allowed. Foam/cap tyres are not allowed but internal foam inserts are permitted. Tyres will not be modified in any way that will affect their original dimensions or construction; tyre beads can be trimmed to fit into bead mount areas of rims.
9.6 Control Tyre Selection
9.6.1 The type of tyres and combinations are decided by the AARCMCC Electric Executive together with the race organiser (from race organiser recommendations). The race organiser will forward the recommendations to the AARCMCC Electric Section four (4) months before the event. The final decision will be made Three (3) months before the event, between the AARCMCC Electric Executive and the race organizer.
9.6.2 The selected controlled tyre for all classes must continue to be commercially available in all Australian states for six (6) months prior to the event and up until the commencement of the event.
9.6.3 The host club has a duty to ensure that, as part of its selection process, the preferred tyre will be readily commercially available from Australian hobby shops for the duration of the period from their announcement until the meeting. The tyre combination should also be suitable for expected weather and track conditions.
2WD and Truck: Rear tyres controlled only, front tyre is open.
4WD: Front and Rear tyres are controlled, different types maybe selected for the front and the rear axles.
9.5.1 Tyre type: Rubber only with foam inserts.
9.5.2 Control tyres must be used for all classes.
9.5.3 Specified control tyres must be fitted on the correct axle.
9.5.4 All tyres must be black. Foam tyres are not allowed. Foam/cap tyres are not allowed but internal foam inserts are permitted. Tyres will not be modified in any way that will affect their original dimensions or construction; tyre beads can be trimmed to fit into bead mount areas of rims.
9.6 Control Tyre Selection
9.6.1 The type of tyres and combinations are decided by the AARCMCC Electric Executive together with the race organiser (from race organiser recommendations). The race organiser will forward the recommendations to the AARCMCC Electric Section four (4) months before the event. The final decision will be made Three (3) months before the event, between the AARCMCC Electric Executive and the race organizer.
9.6.2 The selected controlled tyre for all classes must continue to be commercially available in all Australian states for six (6) months prior to the event and up until the commencement of the event.
9.6.3 The host club has a duty to ensure that, as part of its selection process, the preferred tyre will be readily commercially available from Australian hobby shops for the duration of the period from their announcement until the meeting. The tyre combination should also be suitable for expected weather and track conditions.
2WD and Truck: Rear tyres controlled only, front tyre is open.
4WD: Front and Rear tyres are controlled, different types maybe selected for the front and the rear axles.
Personally I think it should be 1 set per 2 races in Mod, and one set per 3 races in Stock. If a soft compound won't last that long then a harder one needs to be selected.