Maybell

iTrader: (2)

here=hatchet center! opposite of wrench....

lets take great new designs and regress them 10 years!

yah, that will be dialed!

John Stranahan

iTrader: (27)

Its hard not to reply to your rudeness, twice now. But how do you figure that removing 20% off the weight of a race car is regressing 10 years. We basically have off-road sized shocks because those were produced first.
John

adamge

iTrader: (1)

John, those look like steel fasteners on your car. You can save around 25g by switching to 7075 T6 Al.

rezenclowd3

iTrader: (17)

Those look to be rc18t shocks? I used to drive one at Revelation in Ontario quite often, however I switched to the Losi Mini-T shocks because 1)they didnt leak near as much 2)They felt much smoother 3) Were easier to build IMO.

Good luck! Maybe a vid of you racing sometime?

John Stranahan

iTrader: (27)

Adamge-They are steel. I'll think about using some Aluminum fasteners. The 3 mm size with fine threads have a bit more meat on them than the 4-40 sized screws. Does someone make a kit now for the TC5.

Rezencloud. They are associated RC18T rear shocks. I will try those Losis next time they need a rebuild. One advantage of these is the ball shank uses the same size tap drill as a 4-40 ball stud. The shanks are about the same strength then. How about the Losi. I'll see about a video later on. The new camera can shoot a 20 minute digital video. There is a short video where I am driving a wide pan car against a touring car along with a little discussion here. I am wondering if with a years worth of progress and maybe a little lightening if I can reverse the situation. So far my custom 3-link pan car's best is 17.8 seconds. The TC5's best lap is 18.9 s. Note in the video the pan is not completely sorted out nor is it my custom pan and it is turning 19's. You can see quite a gap developed on the straight on the second lap.

John

rezenclowd3

iTrader: (17)

^^^I dunno...I had the RC18T over a year ago. I only bought it to see if I would like the nasty dirty offroad The guys one the other side of the pit tables from the onroad course seemed less sophisticated also I believe I used the same parts from the RC18T to use the Losi Mini-T shocks. Keep in mind the fronts are shorter than the backs.

Thanks for the vid! Being a nitro guy, its weird to start warming up to tiny electric vehicles. Now if I can find a way to run a pan car with brushless and still be on par with the 4 cell NIMH 19t guys...

adamge

iTrader: (1)

I have a fair bit of experience with the Al fasteners from these guys:
http://www.fastener-express.com/

I've used their Al M3, 4-40, and M2 screws.
I haven't stripped a single hex head.
I haven't stripped a single thread.
And I'm damn happy with their product. These are seriously good screws.

-Adam

yyhayyim

iTrader: (26)

Alumin or Titanium screws will help, as well as Ti hinge pins, turnbukcles, and ballstuds...also using an LRP X11 BL motor will help, as its only about 167g...maybe the LRP 3.5?

John Stranahan

iTrader: (27)

Rezencloud. That would be ideal if the Losi MiniT shocks fit the same Associated RC18T ballstuds.

YYhayyim. Agreed. I am usign the X11 LRP 3.5R motor.

Adam-
Aluminum Screws
I ordered some Aluminum Screws from Fastener Express.There is no screw kit so I ordered the following sizes
25-3 x .5 x 6mm. Flat head Socket head cap crews
25-3 x .5 x 6mm Button Head Socket head cap screws
No shorter sizes are available, but you can cut these down where appearance matters with a Dremel Cutoff wheel. Only the 3 Spur gear screws need to be shortened. This is enough to complete most of the screws that can tolerate aluminum on this kit. I plan to exclude the hinge pivot screws, the two steering bellcrank screws. The screws that hold the motor plate to the rear bulkhead. If you leave this screw loose or missing you run the risk of stripping the spur when you you have a little head on with a pipe. That motor will flex forward and the wheels will be braked hard on the pipe.
The tiny screws I would leave steel as there is not much weight savings and steel is much stronger.

If you are running lead ballast then of course the use of Aluminum screws is not helpful as they are much weaker than the stock steel screws. Stainless steel screws are about 1/2 the strength of the black screws that come with Associated kits as well.

I'll check on Titanium hinge pins. A kit is not available. I probably can meet my 43 ounce target weight with just the Aluminum screws and smaller shocks. This happens to be the weight of the pan car prototype.

Center Shaft Play on braking
I have started to notice a little shudder in the car when I brake. I have traced this to play between the spur gear adaptor and the shaft. That little cross pin beats the slot longer as you apply brakes and then power. On the Losi JRXS I fixed this with blue locktite paste in the slot. I have tried this now on the TC5. I do notice that TIR offers an all metal center shaft/spur gear adaptor. Generally these increase rotating weight over the plastic parts, but it should reduce the play. I loctited the other two cross pins as well.
On most layouts braking is not needed. My track has two hairpins where braking seems to produce better lap times. It is also a more exciting way to drive the car hard.

I have tried three ways to enter the sweeper. Hot, the car tends to drift too wide, a quick shot of brakes has been successful, this is what the nitro guys do. That shudder has been compromising corner entry. Go to coast early and enter not so hot using just drag brakes. I am still trying the 3. With the pan car I can enter full speed hot and it has sufficient turn in to make passes right there.

Note that this adaptor is a good place for Aluminum screws. Because of the high rotational speed they would do the greatest to improve punch.

John Stranahan

iTrader: (27)

Center Shaft and Pinion side Motor Bearings
After reassembling the center shaft. I discovered the driveline had excess friction. I removed the pinion contact from the spur for a good test by hand. The spur side bearing on the centershaft was toast.
My experience with the pan car tells me these 3.5 motors are hard on the pinion side motor bearing and the opposing bearing that supports the spur. Both are much longer lived with a 4.5. This is the case here with the TC5. You need to check this center shaft bearing every time the motor is out. Lube the motor pinion side bearing every two runs or so. The center shaft bearing was sealed but responded to some oil. I replaced it with a spare. It is a 4 x 8 mm ASC 31402. Have a couple of these in your kit. I prefer contact seals for long life outdoors.

The pinion size motor bearing for LRP X11 motors is ASC part # 50608, 9.52mm x 4.762mm x 3.175mm. I believe they will come two to a package. The non pinion side motor bearing will rarely fail and is part #50607. I just hate the way they specify these obviously non metric bearings.

The bearing is also .375, .1875 x.125 These are the specs of the pinion side motor bearing for X11 ordering elsewhere. I would get a ceramic hybrid ( ceramic balls, steel races, steel cage) with a high RPM rating and a yellow rubber seal and oil lubricated for best life (or metal shields). I'll put up a Boca part number after a while. The Novak outer bearing is .5 OD so it will not fit.

These are the posible consequences of a seized motor bearing which I have experienced. Total destruction of the speed control, LiPo battery and Motor. In spite of your stalled rotor protection. Check that bearing often. Oil it often. Put together a set of screws and washers to gently press a new one in its place. A wing nut works nice. It is hard to tell the bearing is going bad on the track. It is easy to tell by spinning the pinion by hand off the car or spinning the spur by hand which is less sensitive.

Here are some specs on my two choices for the X11 motor from Boca Bearings. This is based on a years worth of experience with 3.5's. The rubber seal will make the bearing last longer. The ultra seal is a non contact type but is a tighter gap than metal seals. There will be slightly less friction and heat. Both bearings are rated over 80,000 RPM when run in oil. I found this rating important to keep the cage from exploding on 3.5's. The $1 bearings do not hold up. Failure is somtimes catastrophic on the electronics from the sudden stop and current surge that results from a seized bearing.

Part Number: SR166C-2YS NB2
Product Type: Radial Bearings
Description: Stainless Ceramic Hybrid Lightning Series Rubber Seals
List Price: $13.95
Your Price: $9.95
http://bocabearings.com/main1.aspx?p=product&id=4494&n=SR166C-2YS_NB2



Bearing Material Stainless Steel 440C
Rolling Element Mat. Ceramic SI3N4
Two Seals
Enclosure Material YU Stain. Ultra Seal
Enclosure Type Non Contact Seal
Retainer Material Stainless Steel
RPM Oil (x1000) 90

http://bocabearings.com/main1.aspx?p=product&id=4495&n=SR166C-YUU_NB2

Rub Point
I noticed my front belt rubbing the bellcrank support post. It has worn through the blue. Tightening the belt may have solved the problem or it may need a touch with a small dremel drum sander. It is mighty thin there already.

ooliganRC

John the titanium racing layshaft is good. comes with new pins for the plastic layshaft gears and is much more secure.

I dont have and back lash in my layshaft gears.

kn7671

iTrader: (16)

Regarding the LayShaft and pulleys, mine too starting knocking fairly quickly while running carpet foam stock.

To solve I simply disassembled the it to clean with motor spray, then while reassembling, super glued the two belt pulleys together. You will still keep the pins in the assembly, but while gluing them together place a little rotational pressure on each pulley, like your trying to twist them apart. This twist will lock each pin in their min/max play conditions, thus eliminating the knocking for good.

Granted once you do this, you can't disassemble the belt pulleys from the layshaft, but you really never need to disassemble it anyway. The only parts that need servicing are the bearings and spur gear, the rest can stay together forever.

John, clean all that blue crap out and glue the pulleys, I promise you will be happy with the results.

thunderbt3

iTrader: (14)

I had some rubbing issues too, i realized that my front diff was in the wrong direction. I flipped the diff and problem solved.

John Stranahan

iTrader: (27)

Kn761 Nice tip! I'll try it if my blue crap does not work. It worked fine on the JRXS. I assume you glued the pulleys to the spur gear adaptor which is where most of my play is.

Thunder BT3-Thanks for the post. My diff is in the right direction. Front belt is on the left. It is a light rubbing that might cost a little bit of speed.

OoliganRC-I like the rotational inertia advantage of a plastic spur adaptor. It might be a close call though. I'll try a couple of these fixes first.

ooliganRC

TiR layshaft weighs less than the layshaft and plastic spur adapter.