HonkSolo

Our new GF01 is finished! Yay! I finished the build last week and we went right outside to test it! What a fun drive! I really think the 3000kV brushless motor is a great choice - it easily wheelies, but stays well controllable in general. Even driving on steep areas is no problem as long as one can keep the trigger from being pulled all the way ;-) I've put on the unpainted body shell for now to protect the electronics - after 2 hours of driving the shell looks really worn and torn ;-) I guess I will still paint it! My daughter also likes it a lot. Many thanks for all your help and suggestions!! PS: I was unable to keep the GF01 all stock, so my upgrades are all-sealed roller bearings, a 3000kV brushless motor and Mini CVA shocks (using the single hole pistons and large eyelets). We drive a lot on uneven ground (and also jumps etc.) and I cannot imagine the original shocks (pogo sticks) to cope with that well. For me that's a great combination and strongly recommended.

Yeah I got infected by the LiPo paranoia as well and went for NiMH for my current GF01. I knew that Li-batteries are everywhere and initially thought LiPo is a more dangerous variant of it. When I read up on LiPo I found that LiPo is indeed the current standard Li-battery with a polymer electrolyte (instead of a solid) that allows more freedom in the design of the battery shape. This is what is everywhere being used - in smartphones, tablets, even in houshold appliances etc. So for these devices nobody appears to bother at all about Li-batteries, but for rc cars it is a major concern? Of course for rc cars the batteries are being operated under harsh conditions (vibrations, shocks) and close to their max current ratings, so that certainly increases the risk for failure to some extent. Also the battery pack contains many large cells which makes quite a catastrophe when the battery goes mad. On the other hand, my laptop has even more cells in its battery and I don't worry about that at all.

You loose some, you win some. Trading performance for safety. I'm not aware of any soon-to-expect progress in battery technology that improves in all aspects at the same time.

Pretty standard engineering office space - at least mid 90ies I would guess from the use of 3D CAD.

Very nice! And a nice paintjob too!

There is already such a thing - LiFePo batteries. They are being used in motorcycles for many years now, do not need any special treatment and are very safe. Tamiya promotes them too, but they appear to be difficult to get in Europe for rc.

Not related to RC cars but still fun: I had a GPS mounted to my motorcycle; it required mounting an adapter and replacing the original screws with longer ones. I had the GPS mounted for 10 years and then sold the bike to a friend. I still had the original screws and gave them with the bike to my friend; he would remove the adapter, return it to me and fit the original screws. Guess what? He lost the screws I had stored for 10 years within one week.... He couldn't find replacements, so I had to wait months for the GPS adapter ;-)

I checked and cannot easily find a 18 teeth Tamiya steel pinion? Do you have a part number or link to an online store? Thank you ;-) In 1:1 sized equipment, yes. In RC-cars with its high rotational speeds 10 to 20min of running should easily do.

I'm sorry I did not intend to sound like Mr. Smarty Pants in my previous post. It was written in a hurry ;-) I do have a very long professional background in lubrication, friction and wear in machinery development, but my no means I assume that that is required for rc cars. If you don't have any issues with wear and tear with the gears than that's nothing to worry about. On the other hand I read the recommendation to use a steel pinion for the motor, so I automatically assumed there is some wear for the original Aluminum one and proper lubrication would be useful. In any case many thanks for the grease part number - I already ordered it together with CVA shocks ;-) I'm excited to continue building!

I see your points! Whatever works for you - I guess with an RC car one gets away with this minimum, almost non-lubricated contacts. That is a common misconception. Grease is worked out of the actual contact during the first operating hours. The excess grease then serves as sealing (in roller bearings) but still provides some reserve for lubricant replenishment. Churning losses (that's the technical term for 'more difficult turning gears') go down too. Also, this 'more difficult to move' is usually tried by rotating the gears without load (no torque being transfered) e.g. by hand. Then that's obvious - however, just put some torque on the gears and also non-lubricated gears will have more friction. Also, never assume industry uses too much of anything! They will always save whereever possible, be it only millicents.

You sure? This is grease! Use enough to cover the surfaces with a thin film (it is also for corrosion protection on steel parts). Just like it is done when assembling real engines ;-) The GF01 has many gears with large teethed areas, so the original tube goes flat very quickly....you also build 3-4 GF01's with one tube??

Today I had fun assembling the gear box of the GF01 - nice! However, I wonder how to handle the grease - 3gr is included and it is already gone! Yes, I like my gears and bearings well lubricated! I need to order more - do you have any particular recommendations? Is the original, included tiny tube considered to be sufficient for the whole model?

Yeah, I had that many times too. No discussion with the seller usually helps. In many cases refusal to send to other countries is written in the article descriptions in a way that makes you think that people from other countries are all criminals. Even with payment in advance by bank transfer some apparently still think there might be ways to make the money magically disappear after the item was shipped. Or, if not that, that the buyer will certainly complain aggressively afterwards. IMHO, there is a lot of fear of the unknown online that borders to paranoia. Strangely I get the impression almost never from buyers, just from sellers that sell only a few times a year stuff (online). Just for your reference: I'm buying and selling new and used stuff online on all platforms to all countries (even a few times outside EU/USA) using all payment options (even Western Union once) for 20 years now. (I'm not a professional or a business, just hobbies) Zero troubles except one fraud attempt. No lost packages at all, just one package taking 15 weeks to Sweden. Even in that case the buyer was patient (I had mailed him a photo of the package before shipping and then a photo of the shipping receipt, sadly shipping was without tracking). All that is needed is a clear and concise description of the articles with useful photos. EDIT: Thinking of it I find the fixed price agenda to be related. Some ads rather rudely state that their offering is fixed in price, no offers will be even responded to (why?? Are no offers better than one a bit lower in price?). I often get told that people refrain from selling online because they fear to constantly get "what's your lowest price" messages (which apparently they would find overly annoying). For me that's also part of the "fear of the unknown" as I don't have any such experiences. Certainly, people are often asking for a discount, because - quite understandably - everyone wants to save money (that's why we buy 2nd hand in most cases, no?). I usually consider that already in my initial price offering and can always go a bit lower.

GF01 Toyota Land cruiser ;-)

Maybe an update to that story could be of interest. The 1V battery pack charged without hickups to 8.4 V (as should be for a 6 cell pack), which looks very promising! However, my charger does not detect the 0V battery pack (which is not surprising). I read on the interwebs that some simply connect a fresh battery pack (same voltage, same number of cells) to it - so to jump start the shorted out 0V battery pack. Apparently, dendrites form in deep discharge which shorts the cell, leading to 0V. Jump starting such a cell with a high current (probably 20 A or so) burns out the short and is rumored to revive the cell. Well, I would never have thought of something so brutal (such a jump start certainly pumps dozens of amperes into the 0V battery pack), but I'll tried it due to lack of other options. The 0V battery pack indeed jumped in voltage to 4V or so and the charger charged happily. But only to 5.9V and then finito. No choice of charging current brought the 0V battery pack higher than 5.9V. It made the impression to me that 1-2 cells are still shorted. Given that I was prepared to dispose this 0V battery pack (responsibly) I give the 0V battery pack another 2-3 jump starts with the other (now full) battery pack. And whamm - the 0V pack goes up to 8.4V! Amazing, would never attempted such a thing but appears to be powerful. I'm curious if they stay up during use or if they go flat instantly, we'll see...