Jump to content

Recommended Posts

So I have bought myself a well used (I admit this may be a bit of an understatement) Gravel Hound from everyone's favourite on-line bidding site.  As is often the way I was looking for a new Tamiya project (snappily codenamed the Christmas/Birthday money project) and I happened to stumble upon this little fella.  I wasn't looking for anything in particular just something new and as I haven't owned anything on the DF-02 chasis before I decided to take a punt as the price didn't seem to bad.  To be fair to the seller he was upfront and honest with his photos and description -

 

"very used RC car in semi working order with plenty of wear due to age and use"



 

And it's hard to argue with that.......................
 
20190318_124051s.thumb.jpg.43947e51064d5ef65a59d3c86c3dc0cb.jpg
 
Freshly out of the box and bubble-wrap....
 
 
20190318_124518s.thumb.jpg.81ca90c78e0449f6c98f4ccfef358ab5.jpg
 
It has certainly been enjoyed!
 
 
 

Share this post


Link to post
Share on other sites

20190318_124741s.thumb.jpg.07bf17e243e92b710debcbc37359ab2d.jpg

Enjoyed rather a lot actually......

 

20190318_124607s.thumb.jpg.2c7e38b4aa6b310b1f1dfa05cfcc44ba.jpg

A slightly saggy back end (but then most of us have)

 

20190318_124658s.thumb.jpg.d8285a0a980756228cdb5f879712be53.jpg

Admittedly a bit of a wash wouldn't go a miss either!

 

20190318_124300s.thumb.jpg.5b716a52285532534dd40060426bad6a.jpg20190318_124246s.thumb.jpg.65f826c637cf31f7a017fc543edc8797.jpg

 

 

The shell isn't too bad at all considering the state of the body.  Aside from the piece missing from the front the lexan is in a decent state as are the majority of the remaining decals.  After a much needed wash (for the shell not myself) I'm hoping to leave the decals that are up to scratch and possibly replacing the others with some home made attempts.  I will definitely be removing the paint and choosing something a little less green!  

 

But that is for a bit later...............now it's out with the tools!

 

  • Like 5

Share this post


Link to post
Share on other sites

Stripping the car down it was obvious that there were issues with both sets of joint cups, dog bones and all four uprights.  It all seems to have stemmed from worn plastic bushings which have allowed extra movement in the wheel joints, and so in the drive shafts and finally in the cup joints attaching to both diffs on both sides.  What is more I don't know if it is simply the passage of time or that these bushings have become very hot but they are unmovable from the hubs.

 

20190325_154521s.thumb.jpg.f48913f889eb034dbd5078fc35b0f46e.jpg

It might not be clear above but the dog bones are worn like pickaxes!

 

20190325_154725s.thumb.jpg.31bbc4f345d32108165e1f1d84b6aeba.jpg20190325_154558s.thumb.jpg.a60a18f7be5e0f246d34046e2a445fe2.jpg

 

20190325_160157s.thumb.jpg.e5fe6e469b59862006d37aa68b213f37.jpg

Interesting use of the glue gun but I don't think it helped much

 

20190322_121508s.thumb.jpg.bbdaf96215a3ac7d465495d34e9e9bf1.jpg20190323_182722s.thumb.jpg.e09255b55701dfefb7d168529df2ed48.jpg

 

Given the amount of wear externally I wasn't sure what to expect in the gear box departments.  Turned out to be a bit of mixed bag.  Worth noting that although the bearings are heavily corroded the gear boxes were pretty clean inside.

 

20190328_135527s.thumb.jpg.05b40a53571d3753389f2fd9a45e3214.jpg

This is what I found inside both differentials

 

20190329_155000s.thumb.jpg.7a766f574a84e5beb542410e53d146df.jpg

After a good scrubbing in soapy water - still not great!

 

20190410_175815s.thumb.jpg.9a33467b3f221c54c3c130bbdc31fe91.jpg

As good as I'm going to get metal wise at least

 

The substance in both differentials proved really difficult to clean.  It was tightly packed in and made up of very fine particles (like clay powder).  Given that both units seemed well sealed is this what is left of the grease/oil mixed with ground metal powder from the noticeable wear on the star shaft and the backs of the small bevel gears (they are all worn flat and should have a circular ridge)?  Despite all this the gear casing themselves seem in good order (does anyone have any advice for cleaning them further as I feel I have gone as far as I can with my cocktail stick and wet wipe combo! - would boiling them up be a good move or a terrible one?) as does the spur gear and both propeller shafts.

 

Next it's on to what is clearly masquerading as suspension!

  • Like 3

Share this post


Link to post
Share on other sites

I must admit that I had read various accounts and opinions regarding the exact make up of the Gravel Hound XB suspension and so I wasn't sure what it's exact make up would be.  All looked good from the outside so I was expecting oil, piston rods, o-rings and seals but what I got was this!  Nothing left in the dampers themselves other than the residue of some very unpleasant looking white gloop.

 

20190410_181121s.thumb.jpg.e649bd7f1ac939d8aad2f229699fc968.jpg

My new additions to my spare/scrap box (x4)

 

Not sure what else to add here.  They were always going to be replaced so I didn't bother to even give them a wash.  I did, however, measure them before stripping them down:

 
Front 70 mm (centre hole to centre hole)
Rear 95 mm (centre hole to centre hole)

Share this post


Link to post
Share on other sites

:D It certainly is TwistedxSlayer which to be honest was part of the attraction - I like the idea of it having a bit of care and attention thrown it's way and enjoying a second life.  The only problem is the more I looked and cleaned and thought the less of the original car is left!  Updates coming soon.........

  • Like 1

Share this post


Link to post
Share on other sites

While I find myself at the mercy of the post man I decided to keep myself busy with a look at the electronics that came with the car.  Naturally this involved removing quite a bit of mud and general filth from pretty much every component using my now trusty wet wipe and cocktail stick technique.  In keeping with the rest of the car this was very much a tale of the good, the bad and the down right ugly - but isn't that half the fun!

20190506_163413s.thumb.jpg.35b122c51bab3b915be71f80e03cd135.jpg

That really is a clean as I can get the motor!

 

 

Tamiya TP-S3003 Servo
 
 A good clean was all it needed so happy days and here's to many new turns ahead (though I'm pretty sure not in this car).
 
 
Tamiya TEU-101BK Esc
 
 The cars Ebay listing stated that the switch wasn't working so I was fully expecting a bit of soldering one way or the other but it turns out that there was that much mud caked onto the rubber switch cover that it was stopping the movement of the switch.  
 
 
Tamiya TP-R132JE AM 27MHz Receiver
 
This car really did have the full Tamiya package!  Unfortunately the ariel wire had been snapped and I couldn't seem to find a definitive answer as to it original length.  I have a few other 27MHz receivers but they are all Acoms so I concluded that their length and thickness was the way to go so a new wire was sourced, soldered and cut to length - 49cm from outside the box to be precise (though I should say that what was left of the original wire was of slightly thicker gauge).  Happily it seems to have been worth the £1.99 wire investment though I have yet to test it's range.
 
 
540 Silver Can
 
Described as "running a little rough" the motor does turn over but is best described as sounding very much in pain.  Aside the noise and the smell of burning mud the whole armature rocks forward and back as the sparks fly and more dried mud falls from its housing.  I'm no motor expert but all doesn't seem well - connecting wires to be removed and the rest filed under b for bin.
 
 
 
 
If I'm honest I'm still not sure what if anything is going to go back in the car.  I have a few Hornet/Grasshopper type projects that I want to give my attention to at some point so anything I don't use on this Gravel Hound will be used in them.  Certainly I am going to install a 2.4MHz receiver and I was toying with an upgraded steering servo (Hobbyking perhaps).  The Esc depends on which motor I finally settle on but at the moment that ranges from a Tamiya Sports Tuned to something from the Super Stock family but that is likely to change knowing me!
 
Now where did I put that horrible green shell?

Share this post


Link to post
Share on other sites

This is just the kind of project i like. Striping, cleaning, assessing and repairing.  

  • Like 1

Share this post


Link to post
Share on other sites

Given how expensive tamiya motors get quote quickly I have been just going straight to 13.5 brushless with the Tamiya tble02s ESC on most of mine. Its not the most sophisticated, but gear the car appropriately for the motor and they properly go. Lipo helps too, just get a little voltage alarm for a couple of quid off ebay. 

  • Like 2

Share this post


Link to post
Share on other sites

graemevw - Don't get me wrong I appreciate a nice, fresh, out of the box build as much as the next man but for me there is a certain extra layer of satisfaction in the striping, cleaning root - plus until you get to have a good look at everything you never really know what you've got.  Though in saying all of that with all the hop-up parts I am waiting to arrive I think this time around I may be a little hypocritical with regards to that statement - but I'm desperately trying to use original parts :unsure: 

Share this post


Link to post
Share on other sites

Hi thunderDragonCy and thank you for your post.  I am genuinely unsure which way to go regarding the motor.  Initially I was thinking I would reuse the TEU-101BK Esc as I have a couple of new Sports Tuned motors waiting for a home (but now I'm thinking these would be a better fit for the afore mentioned Hornet/Grasshopper projects).  My only other options are a couple of Super Stock motors (RR and BZ) but given the price of new brushes I'm not sure that is the root to go down for a car that I intend to use frequently.

I don't own anything brushless but I have been reading up on them but I am happy to take advice from someone more experienced in that field.  I was thinking of getting a TBLE-02s as a solid (and not too pricey) starting point but I only own and use NiMAH batteries as it stands.  Please could you give me more details regarding your 13.5 brushless motor.  Hopefully I can say thank you in advance :rolleyes:

Share this post


Link to post
Share on other sites
20 minutes ago, stoatyWeasle said:

Hi thunderDragonCy and thank you for your post.  I am genuinely unsure which way to go regarding the motor.  Initially I was thinking I would reuse the TEU-101BK Esc as I have a couple of new Sports Tuned motors waiting for a home (but now I'm thinking these would be a better fit for the afore mentioned Hornet/Grasshopper projects).  My only other options are a couple of Super Stock motors (RR and BZ) but given the price of new brushes I'm not sure that is the root to go down for a car that I intend to use frequently.

I don't own anything brushless but I have been reading up on them but I am happy to take advice from someone more experienced in that field.  I was thinking of getting a TBLE-02s as a solid (and not too pricey) starting point but I only own and use NiMAH batteries as it stands.  Please could you give me more details regarding your 13.5 brushless motor.  Hopefully I can say thank you in advance :rolleyes:

I use Speed Passion 13.5R MMM 3300kv motors in most of my cars, mainly because they are available for a good price in the UK. I had this motor on a tble02s in my DT03 as my first foray back into rc a couple of years ago. The esc with this power motor has no issue at all, and I have run 7.2 and 8.4 nimh as well as high C rated lipo with no problem at all. Some people have trouble setting up the esc, but if you buy a kosha version with a paper manual to read and follow I haven't found any trouble. Bonus with brushless is you can adjust neutral stick (drag) braking and overall braking power which means you can tailer them quite well to what you want. It sounds like you can solder, so you will just need to clip the Tamiya motor plugs off and solder to whichever motor you buy. The key with brushless is gearing. For 13.5 or anything around 3000-3500kv you need to get the final drive ratio (FDR) down to 7 or a little less. All mine with this motor run around 6.7 quite happily and fly along. 

  • Like 1

Share this post


Link to post
Share on other sites

Had a quick look at the df02 manual and it is very low geared as stock. Doing a bit of searching on here it would seem that your solution if going brushless is the TT01 58t spur gear from 53665 and a 0.6module 22t pinion. Will give you a FDR of 6.85 which will be spot on. 

  • Like 2

Share this post


Link to post
Share on other sites

Thank you very much ThunderDragonCy for your effort and advice - very much appreciated.  Given what you've said I think I will stick with NiMAH for now (mainly 7.2v to be honest) and will look into both the Speed Passion 13.R MMM and your gearing recommendations - and also price them up!  I was able to arrive at your Final Drive Ratio of 6.85 (took me a while to count the diff gears!) but I was wondering why with a 3000-3500kv motor 7 or less was the goal (certainly not doubting it but purely due to my own ignorance)?

Share this post


Link to post
Share on other sites

I don't know the exact science, but brushless motors have much, much more torque than brushed, and maximum torque from zero revs, so you can get great performance from relatively modest motors by gearing them right. 

This is a gearing chart I use that I found on the Internet a while back and its proven really good. 

2019-05-03_01-13-55

 

  • Like 2

Share this post


Link to post
Share on other sites

I see, thanks for that, and I'm pleased that you don't know the exact science either :D 

I've been looking into the combination that you suggested and happily I think I can afford it - bye, bye birthday money :blink:.  Looks like I will have to get a TT-01 motor mount to accommodate the 22t pinion but an alloy upgrade would seem sensible anyway.

Just in case of any doubt I take it this is the specific motor you were referring to:

https://www.modelsport.co.uk/speed-passion-1-10-competition-mmm-series-13-5r-bl-motor/rc-car-products/368333

Share this post


Link to post
Share on other sites
17 minutes ago, stoatyWeasle said:

I see, thanks for that, and I'm pleased that you don't know the exact science either :D 

I've been looking into the combination that you suggested and happily I think I can afford it - bye, bye birthday money :blink:.  Looks like I will have to get a TT-01 motor mount to accommodate the 22t pinion but an alloy upgrade would seem sensible anyway.

Just in case of any doubt I take it this is the specific motor you were referring to:

https://www.modelsport.co.uk/speed-passion-1-10-competition-mmm-series-13-5r-bl-motor/rc-car-products/368333

Thats the one! 

  • Like 1

Share this post


Link to post
Share on other sites

Love restoration threads. Seeing a beat, muddy mess come back to life is as much fun as building new imo. 

Boy, got your work cut out on that one. Driveline looks like it has taken a beating! 

  • Like 1

Share this post


Link to post
Share on other sites

I certainly agree with you regarding all (maybe most :o) things restoration wise OldSchoolRC1 and you're spot on regarding the external drive train - but in saying all of that I bet a load of fun was had but seemingly little in the way of maintenance. 

Still, one man's unwanted toy is another man's project :D

Share this post


Link to post
Share on other sites

The weakness in the DF-02 chassis is pretty well documented and I decided to address the problems surrounding the U-shaped shaft set-ups as best I could.  Stage one I think is universally accepted as the way to go and that comprises of reinforcing the underside of the chassis 'lugs' which hold the U-shaped shafts front and back.  My product of choice following a few test subjects was good old Milliput (the black variety needless to say).

 

20190513_152907s.thumb.jpg.2b55929a8216139b7289265fa947303e.jpg20190517_154047s.thumb.jpg.bff6256ad41d945e35885f4b33d867a3.jpg

Before and after

 

I'm not sure if this counts as a spoiler alert but I sort of feel like I need to justify what I did next and why!  As part of my shopping spree I was lucky enough to acquire the rear carbon fibre skid plate made by Square (STG-15R).

 

818RNs9elmL._SL1500_s.jpg.ef404f9fa70bbddbb129df44ba924830.jpg

A thing of beauty!

 

I do intend to fit it at a later date (with a slight mod to it's set-up which by reading on I have no doubt you can guess yourself) but since I'm going to be using the buggy for a fair bit of bashing about for a while, I'm almost ashamed to say it but, it's just too good to risk at the moment!  Given that the carbon fibre plate sits 1 mm lower than the rest of the chassis  (which already has more deep grooves than a 70's disco) and coupled with my limited driving ability it wouldn't take long for there to be tears a plenty.

However, inspired by the anodized loveliness I wanted to see what I could do using the original bumper/skid plate.  I know there are a number of discussions and solutions dotted around the inter-web, and I'm certainly not trying to claim I have reinvented the wheel or take credit when it isn't deserved, but this is what I have ended up with:

 

20190517_172441s.thumb.jpg.f6759b1134c112af8c768e957f951208.jpg20190524_154218s.thumb.jpg.c0a8dd353b4bcc5e5e26cb7026806e61.jpg

 

It is certainly good and solid with no slop in the arms but I wont bore anyone with any of the finer details (unless asked and I happily will do) but I would be interested in what people think - be it good or bad.

 

20190517_172748s.thumb.jpg.d6c5011383119072b445349209a71840.jpg

 

 

Admittedly the above photos isn't going to win any photography awards but hopefully it demonstrates that the two nyloc nuts (complete with rubber washers on the back) don't interfere with the pinion or the standard 70t pinion.

  • Like 4

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×
×
  • Create New...