John Stranahan

iTrader: (27)

Nimo-Thanks for the posts. Hope they see the light over at BCRA. I am not a fan of 1 cell either.

Gareth-here is a view of the 1/12 car from the back. I still need a new bottom and top plate to move the motor to the right. I have in stock now the new "brushless" hubs to allow this. I have a 66/41 gear in the car now to run some stock on a tight track.

john

JR007

That is exactly why a few friends and I are trying to get 1/10 pan back by using 13.5 and 2 cell Lipo. Down here 13.5 is our Superstock touring class, so a lot of guys have the electronics, it's just another chassis.
Also, 90% of our tracks are outdoor asphalt, and watching a 1/10 on single cell go around would be slightly more painful than watching paint dry!

John Stranahan

iTrader: (27)

JR007 Well good luck.


1/12 Scale Dual A-arm Front End, 3-Link Rear End

I thought I would talk about weight with the new Prototype 1/12 scale. It seems that 730 grams must be just achievable. Well you don't get something for nothing so I expected to add a little weight because of the front end. It is know 10 grams heavier than the CRC front end. It is ideally oil dampened however which is worth time on the track.

I had the LRP TC edition dummy speed control installed, I was at 212 grams for the chassis only without body. I had no idea what bodies weighed at that point but the Protoform Speed 12 b light weight I have now is 44 grams with the paint over spray film in place.

I removed the LRP speed control and added a new Havoc one cell speed control with built in voltage booster. The Novak box seemed really heavy. I put the speed control on and two problems developed, I gained 10 grams and was at 222 grams. This is without the glitch buster receiver capacitor they recommended. The unit was also very tall.

This is what I did to shave a few grams. I removed excess speed control signal wire and servo signal wire with a splice. The servo wire was very long so this netted 3 grams. I removed the switch as I normally end up doing on most of my cars for reliability. One battery lead removed makes a nice switch. I cut battery and power wires to a minimum while allowing a nice radius. I replaced the motor sensor wire with a shorter flex version. I replaced the Beautiful Red aluminum O-ring posts with a modified plastic wing nut. I cut the heat sink down to a flat plate but left a course 60 grit finish for high surface area. This was just cheaper than paying shipping and cost for a new short heat sink which is available. By the way the heat sink presses on some rubber conductive material that is more like a gasket, so it is easily removed and replaced. The chassis was now 206 grams. I lost 14 grams. So with body and without transponder I am at 250 grams or 20 grams over. I don't see anywhere else to cut significant weight. I know a cheesy non metal gear servo would save some.
John

John Stranahan

iTrader: (27)

1-12 Scale Carpet Knife V3.2

Work continues on the carpet knife. I had mentioned the need to offset the motor for brushless. It would need to be moved right by .160 inch based on the difference between the new brushless CRC hubs and the old Carpet Knife V 3.2 hubs. I plan to do this. If anyone is interested here are some PDF files that can be printed, Cut out, taped to graphite plate, and reproduced with a Dremmel. I have put extra lines in the holes to help align a center punch.

The procedure on a small drill press would be center punch, drill with a small center drill (#1), through drill with a .113 drill, countersink the bottom side of the bottom plate which is shown with a 82 degree countersink bit. Cut out with a Dremmel cutoff wheel. Sand with a medium grit medium size Dremmel drum sander and then follow with the small diameter sander. Wear gloves, sleeves, and respirator.

These two plates will breathe new life into an old very nicely made V 3.2. There are a couple of extra holes in the bottom plate for the 3-link, don't drill those.

If you don't like the shape of the top plate draw your own shape in tracing the old part . I think this will allow a top install of motors with lead wires soldered on. I will find out tomorrow.

As far as I know these are not available for sale.
john

John Stranahan

iTrader: (27)

Here are a couple of pics of the new brusless pod for the Carpet Knife v3.2.

The motor has great clearance on solder tabs and is an easy top install now with leads soldered on. In addition I get a very rugged and stiff chatter free pod for 3-link use. Short test tomorrow on a tight outdoor asphalt track. The mod makes the left and right side pod weight more even and took away a nasty tweak problem on the main frame as well.

It seems the new ads in the picture viewer are clipping the bottom of the picture on my machine. Click again for a full size view.

Yes I will call this the Scimitar 1/12 Prototype, but I have no plans for production.

John

tudor_47

Hi All!

As I understand it the 235mm chassies are not 235 mm wide over the rears?
how wide are they?

and how wide is the front? outside wheels?

I have a Xray X10-link and I would like to make it wide but that requires making parts for it... so I need to know the width at front, so that I know how much I need to widening the mounting plate..

thanks!

John Stranahan

iTrader: (27)

The rear of wide pans varies from 220-235 mm. My new Scimitar is at 232 mm at the rear. The front is about 215. Both with BSR tires. That is a good fit to the bodies.

John Stranahan

iTrader: (27)

1/12 Scimitar Prototype Ready for test.

tudor_47

Thanks John!
PS
I am thinking of getting a car from you ......
as the Xray can NOT fit 48Pitch spurs as they get to big diameter, so that there is no room for pinions...
I got a 92T spur and it left me with 1mm space between the spur and the empty motor shaft! No room for a pinion there!

So I am not sure what to do when I get a hotter motor such as the 3,5T when I need to go 48P...... I am now running 64P as I have no 48P spur that fits..

John Stranahan

iTrader: (27)

tudor 47- When you get an urge to buy that 3.5 give my new Scimitar Pro 10 some thought. It does have good clearance for spurs and pinions. I have run 93/15 in it.


Scimitar 1-12 Scale First Track test with body

I put about 20 minutes on the car today on a tight outdoor asphalt track at M&M hobbies in Houston. First I will have to say the 1 cell 17.5 car was pleasant to run. I felt I had enough power for the job at hand. the 1/12 scale suited the small tight track. I first ran on the layout with dust on it. Cornering was very good. Corner exit was good. in the middle of the straights I could over throttle the car and cause a snap spin. That is typical pan car. Good corner exit manners is not typical on the larger more powerful scales when its dusty. I thought I could drive and race the car well on the dusty track after I got used to the car.

Then we treated the track with sugar water.
I ran at the same time as Dan with a 4 cell pan car. In the beginning, I felt he was gaining on me, but then I just put the pedal to the metal and started gaining on him. I swapped over to his car and Chris drove my car. I drove quite a while getting used to the car. It was a bit darty in the front. I got the feel for it and was making good laps. At this point Chris passed me with my car, but then he is just faster regardless. He could drive the car right off the bat. Dan could not and was banging the boards. I don't know why and after driving his car I am surprised.

So what is the difference between the two cars. First I did not see the standard pan car (CRC I believe) in the dust. I have seen on there in the dust and it was just a handful. Mine was better behaved. On the treated track my car was much more supple. The body did no clang. It did hit the ground with body and chassis like the other car. I felt I had more mid corner steering with mine with the car at some roll. The standard car did not roll perceptibly, but it had good traction with the sugar water.

Note the two cars are not equal in voltage or weight. Dans pan running 4 cell is probably heavier but has an extra 1.2 Volts or so. A one cell LiPo is really equivalent to 3 cell NiMH. I don't know which is typically faster.

Adjustments-On the dust I thought I lacked a tad of steering coming of the straight. I raised the outer lower arm .020 inch at the kingpin with shims. Now on the sugar I had too much steering. I turned the dual rate way down. I went back .010 on the shims and liked the result a lot. No extra steering throw like SW tour was talking about on the oval. I did not bring a set of springs. I ran a 3 lb/in in the front and a 1 lb/in in the back. I may work better with 2 lb all around.

Here is a short video of practice on the tight track. We have a 1.1013.5 2s car chasing a 1/2 touring car with 2s, 17.5.

http://redirectingat.com/?id=42X1295...%23post7903728

John

Watchman

What's the latest on the WGT and 1/12 cars...??

NiMo

CRC Gen-X10LE

Watchman

I was inquiring on the latest for the Scimitar Oval, Scimitar Pro 10 and Scimitar Pro 12 cars...

John Stranahan

iTrader: (27)

Watchman thanks for the interest-

Scimitar 1/12 Prototype, Track test.
I had one more session with the car this time with a bit less traction. In the previous test the car seemed perfect. Huge turn in traction, very adjustable with front roll center, little tendency to lose the back end. I had 3 lb/in front springs and 1lb/in rear springs. There really was no need to change the setup but then what is the likely hood of having it just right the first time.

I went with 2lb springs front and rear. I got strange results. I lost front turn in (front cornering traction). The car was more supple but not really better anywhere.

I went back to the original setup and turn in returned.

So why the strange results. I have a suspicion that the car was punching through the dust better on the outdoor asphalt track with the stiffer front spring. Normally a rubber tired car will do just the opposite with a stiffer front spring. This car was getting more load on the outside front and also getting more grip.

I have experienced something similar with the wide pan as I changed overall weight of the car. I found at 39 ounces it was just not punching through the dust well. Forward and cornering traction were reduced. At 43 ounces good traction returned.

Anyway on asphalt these are things you might try in reverse (stiff front spring, heavier car) if your car is not gripping well.

Scimitar oval and wide pans are awaiting a shipment of parts.



CRC Gen X 10 LE

This car is pictured above. Thanks NiMo. If it was sized a little smaller though we would not have to scroll to read this text.



I thought I would comment on some changes.

• The front chassis brace is now included
• The battery top plate is minimized like most of mine are at present. This saves some weight.
• There is no battery tray nor slots for NiMH cells. This should allow the placement of the battery slightly further back against the football. This will free up room at the sides for electronics closer to the battery.
• The chassis has lost its diamond shape. It is a little narrower at the middle like my Scimitar wide pan.
• The rear of the pod has a beefier X brace. This should help stiffen that minimized left pod plate.
• The front center shock height is no longer adjustable. Truthfully, I don't use that adjustment myself.
• NICE!

JR007

Has anyone tried the Gen-X10 with trailing front axles? Mine ar in-line as per the kit recommendations, but i'm having trouble with stability entering and exiting corners, and thought this might help.
We had very low traction at our last meet, and I was finding that the car was quite nervous, and often hooking coming out of the corner prior to applying any throttle.
At first I thought it was spinning out for loss of rear traction, but it is possibly too much front traction. I'm using Jaco purples and Red springs at the front. Would having firmer springs make the front push more?