A little bit disappointed...

[seph_16]

Hi everyone,

I'm pretty new to the whole scene but I'm sure you will all be able to offer me some valuable advice!

I've just finished building my Gravel Hound (my first proper kit) and I have to say, I'm a little bit disappointed with the speed.  My expectations may have been too high, but it seems pretty slow to be honest.  I'm sure I've built it right etc, no strange noises coming out of it, neither does anything seem to be straining.  Have I done something wrong or do I need more power in some form?  I've currently got the standard 540 motor fitted with a modelzone battery pack nimh 3300 mah which I was told would give me more "grunt".... aparently.

 I've seen the RS-540 motor knocking about on ebay pretty cheap, would that help?

 Thanks in advance,

 Joe

[jwrape]

If it's speed you want put a lower turn motor in it or re-gear it.

[Guest joelvardy]

No you haven't built it wrong (well I doubt it)

The car stock is very slow (sorry to let you down)

I was very disappointed when I built mine, it was slow.

The sports tuned motor wont really help as it is basically just the same as stock (just has different timings)

I would suggest maby a 27t motor, I know that means spending money but there is little other advise I can give you sorry.

Joel

[seph_16]

Sorry if I'm asking a very simple question here, but what does it mean by the different number of turns in a motor?

 Would you be able to recommend a decent 27t one, and if so, how much would it be roughly?

Joe

[Guest joelvardy]

sorry here is a good deal on a 21turn motor  (and speedo)

http://www.modelsinmotion.co.uk/product.as...&tamiya=258

The lover the turns the faster the motor will go there is sometimes a second number this is how powerful the motor is

EG,

A.   13X3   motor is fast and powerful

B. 13X1   motor is even faster but less powerful (better for on-road)

Hope this helps

Joel

[jwrape]

Unfortunately, I cannot recommend a Low turn motor because I usually use 55t motors for my crawlers

[seph_16]

Am I right in thinking that the lower the number of turns in the motor, the higher the RPM, but you sacrifice torque, and vice versa for higher turn motors?  I'm assuming I can't use the Tamiya TEU-101BK esc I just bought and has been in the car for about 6 hours if I get a lower turn motor?

 I'm sorry for the daft questions but I'm sure I'm not the first to ask!

 Joe

[Z]

You're right about the low turns corresponding to less torque. As far

as the esc goes, if you don't go down lower than a 23t motor, your esc

should be fine. Also, Joelvardy is mistaken about the "second number"

in motor designations (sorry, Joel[]). It refers to winds, or the

number of strands in the wire wrapped around the armature (if you don't

know these terms, don't sweat it). Basically, lower winds have faster

accelleration but lower top-end speed, and higher winds have slower

accelleration but faster top-end speed. I hope this helps, not confuse

you more!

[Shodog]

You didn't state whether you built it with bearings or not.  They make a huge difference especially on 4 wheel drive cars because their is a lot of moving parts in the drivetrain

[seph_16]

Don't worry, you haven't completely lost me.  I've dealt with 3 phase induction motors in my job (not quite the same as RC cars!) so it all sounds about the same.  With regards to gearing, do you buy the gears in sets?  I'd prefer to shave off weight somehow and sort the gearing rather than spend a load more money!  Not that I'm tight (well sort of) but this is only meant to be a small hobby, I just walked past modelzone and fancied one!

[seph_16]

The only bearings I used were the one's in the box!  There were a number of metal ball bearings which went on the drive train and the plastic ones which went on the wheels.  Other than the receiver and esc, everything on it came out of the box!

[rhenbelz]

You want more speed, change your pinion gear. More teeth equals higher top speed and lower acceleration. Tamiya gear ratios are usually conservative stock so try a different pinion before anything else. Make sure you aren't over stressing the motor and you should be fine. Want more speed, buy a Tamiya Sport Tuned motor. Cheap, reliable, fast.

[Rabiedmushroom]

My husband's Gravel Hound evoked the same response.

He was hankering after one for about a year before I surprised him for his Birthday. It was slow, and ground the belly out constantly off-road.

A Tamiya Sport Tuned motor and better shocks have done wonders.

Before he broke the driveshaft with enthusiatic driving...! []

 

[Guest joelvardy]

I need to learn the turns bit, I always mess that up!

Sorry!!!

One thing with the DF-02 (your chassis) is that because it uses "U" bolts to hold the wishbones on there is a week spot where they join the chassis.  ( I have 3 broken chassis's in my cellar in you want proof LOL )

[seph_16]

Cheers everyone,

I think i'm just going to put a slightly better motor in, some bearings all round and see what that does. 

 Joe

[KEV THE REV]

One small point to add, the higher rated battery pack just means a longer running time from the charge generally speaking

[Chain Driven]

Hi Guys,

Just my 50p information about the motor turns, the second number in "13x2" is giving you a hint about the torque because it is the number of wires used simultaneously around the rotor. in this case there is 2 wires going 13 turns around the rotor (well, 3x2 wires around the 3 pole of the rotor)

So roughly the higher the second number is, the more weight you have in rotation meaning more torque.

Just thought it might be good to know because before a venerable member of my old RC club explained that to me years ago I did not know what this was all about )

Cheers

 

Jerome

[seph_16]

Thanks everyone for the advice,

I've hunted around ebay and have made a few decisions.  I've purchased a 67t spur gear, but need the pinion to match (am I right in thinking this, or can the motor just be mounted closer?) so if anyone knows the part number or just the no. of teeth on it i'll need then that would be great.  Also, i'm going to get a Tamiya super stock BZ 23t motor and stick that in coupled with a heat sink on the motor itself and the esc, I guess that would do the trick?

 Any more tips would be great!

 Joe

[Gruntfuggly]

Before you put the new motor in, do the bearings. Make sure you remove the grease if you used it when you put the original plastic ones in. You should notice a decent improvement in performance. Once you done that, then try the new motor and see what the difference is like with that...

Don't be tempted to just put the new motor in without changing the bearings.

 

[seph_16]

Thats really good advice, thanks.  I'll give that a go first, then change the motor if I'm still not happy.

 Joe

[ChrisRx718]

Hmmm; so you found out the hard way eh?

Time to make the buggy quicker...

Notice the pinion gear on those things is black. This; my friend, is for good reason. The pinion gear is made of tougher-grade material. Using the standard one; Tamiya found that it melted!

So if you're changing the pinion, be careful that it doesn't get to much stress. ie - don't go locking the diffs with an aluminium pinion.

Secondly, the DF02 is not much of a chassis. It's the next step up from a Toy. Unfortunately, this is the truth about the DF02 and the TT01; designed to be user friendly, easy to assemble etc. The easiest way to go quicker qould literally be to buy a new chassis. A DT chassis like the Desert Gator/Sand Viper are more impressive than the DF02- and they can be modified (only 2wd however)

Maybe a new chassis on the cards?

Chris

[seph_16]

Hi,

wow, that's come serious advice!  I never considered the DF-02 chasis to be a toy, but then again, i'm pretty new to it all.  I do appreciate that there is a lot of money that can be spent on a chasis but this is only meant to be a small hobby just to occupy my time and take my mind off work. 

Considering I have owned the car for about a week or so now, and have run it 3 times, i think spending about £30 on it isn't such a bad way to start off rather than writing it off completely.  I have already bought a new spur gear ($4, and still need some help finding out what the right pinion is for this!) and some bearings (50p each) and a 23t super stock motor is on the way too for a very small sum.  I think some carbon fibre parts would be a good idea, mainly the suspension mounts to raise the ride height, and being a full time CAD technician (although I work mainly on buildings), these probably wouldn't take too long to design.

Out of curiosity, what makes the DF-02 and TT01 chasis slower?

If I do plan to get more into this scene in the future, a Dark Impact will probably be on the cards.  Looks pretty good, I've seen quite a few posts about them and they seem very cheap. 

 Thanks for the advice, and I'll keep it in mind.

 Any more ideas would be greatly appreciated!

 Joe

[civilguy]

Joe-

Where are you located?  I thought it was odd as I am a CAD design/drafter and got back into the hobby after 15 years to get my mind off work as well.  I find that sitting at the workbench and assembling (or fixing after a good bashing!!) is very relaxing to me.  (I'm in NH, USA)

I'm not up on the newer buggies- just having fun with my vintage rides!  Good luck to you-- there are plenty of folks on here with lots of knowledge for you to tap into!  Enjoy.

Jeff

[seph_16]

Hi Jeff,

 Thanks for the reply!  I'm in Kent in England, maybe there has to be a relationship between CAD designers and RC cars!? 

Unfortunately as I've only got one car and very few bits to add on, there's not a lot to fix!  I might take it apart again... just kidding.

I think RC cars are a great past time for people who are interested in engineering and design.  It develops not only practical skills in the building process, but the development and modification makes you really think.  I bet there's people on here that have gained a vast knowledge on subjects where they previously would have had no contact with what so ever. 

I'm not too hot on my American geography, where is NH?  Am i right in thinking New Hampshire?

 Joe 

[civilguy]

Joe- correct, I am in New Hampshire- northeast USA.  It's been mid-30s (F) this week, but tomorrow is supposed to be about 10F.  I figured I best get out and run some today.

My daughter is 7 and getting to be quite good with her Grasshopper.  When I got it out after 15 years of sitting, she disassembled the gearbox and cleaned out all the old, crumbly grease.  She was enthralled with HOW it worked-- we probably spent 10 minutes talking about differentials and bevel gears and how it all works.  Then she put it back together.  But she's a gearhead- in the spring she starts carting classes (go-karts that is).

You'll definitely see a lot of 'engineering' types playing with the vintage buggies-- so much of Rc seems to be RTR which to me is a shame.  Building the kits is something I look forward to doing with my kids.  It gets them thinking and I get to play with toys again!!

Jeff