ThunderDragonCy builds a, er, Thunder Dragon

[ThunderDragonCy 7881]

Yes, I am building another namesake buggy. My original and beloved Thunder Dragon as now modified so far from stock, and i have so many spares as a result that i thought it might be nice to have a stock version. Thanks to some brilliant members and fellow Thundershot chassis sniffers, along with the availability of rere new parts from the Terra Scorcher rere, here is the start... 

Now, when i say "stock" its not going to totally as per 58073. Firstly, i am big on using up as much spares as i can these days, so whilst the rear shocks will be yellow CVAs (with mostly new parts) the front monoshock will be a spares box black CVA2 spaced down to 85mm eye to eye length. 

For driveshafts it will be getting Tamiya DF02 universals at the front because i have some. On the wheels, i can't be bothered with the mega wide fronts and random sizing of the originals, so it will be running black 2.2" wheels with decent modern tyres. I will also be fitting my Super A5 that's just arrived from Shapeways, using the 58mm M05 shafts. 

Motive power is from a 1060 esc and 17t motor, coupled with a steel 13t 32dp pinion from the spares box. 

Other than that it will be bone stock apart from bearings. I am even going to resurrect my original 1989 silver shell, and use the vintage uprights with tall upper arm fixings. 

The plan is to get it running "stock", see what i think of the handling, and do a bit of tuning to get a nice runner. 

Should be interesting. 

[ThunderDragonCy 7881]

Made a start. Used arms are pretty battered, but serviceable. Quite squashed in that way thry get. Used an old 630 beating to take up the slack. I can see me getting some fresh arms at some point and making some sleeves for the inner pivot to keep the arm ends correctly spaced

B8 installed upside down for some toe in. Added benefit of fresh holes for the screwpins

Original vintage on the right. Fire Dragon onwards and rere's on the left. I am using the originals. Will give a much higher roll centre, which could be good for astro and grass which are high grip. 

Rear end together. 

Super A5 installed on the front. Solid! They are on my CTE RC Shapeways store if you want one. 

Front on its way. Need to order some spare driveshafts so i can swipe the universals out of the back of my DT03

Body posts on tub and gearbox and motor installed. Bottom gearbox holes are knackered, so thinking about a solution if i can find an M3 x 75 screw to go all the way through. 

That'll do for tonight. 

[BBenny 12]

Watching with interest. Need to sort out my vintage runner with hinge pins that don't back out every 2 minutes. Also prefer 2 front shocks and thinking of trying to get the terra scorcher mount for better geometry. My shocks need new seals.

So much to do but so little time.

[ThunderDragonCy 7881]

49 minutes ago, BBenny said:

Watching with interest. Need to sort out my vintage runner with hinge pins that don't back out every 2 minutes. Also prefer 2 front shocks and thinking of trying to get the terra scorcher mount for better geometry. My shocks need new seals.

So much to do but so little time.

I got lucky with those. I forgot to say. They are out of the Yeah Racing TL01 set i got off rcmart for a few bucks. I have no idea where the short 25mm pins are supposed to fit on a TL01, I couldn't figure it out, but they happen to be perfect for the 23mm wide blue arm ends. Search Yeah Racing TL-009SV. rcmart have them for $1.99!

[taffer 948]

On 5/20/2020 at 8:51 PM, ThunderDragonCy said:

Made a start. Used arms are pretty battered, but serviceable. Quite squashed in that way thry get. Used an old 630 beating to take up the slack. I can see me getting some fresh arms at some point and making some sleeves for the inner pivot to keep the arm ends correctly spaced

 

If sleeves keep the blue arm ends from bending in on knocks and crashes, won't that just transfer the shock to the hard black plastic???

I've always resisted doing it, in the past I be gone down the path of using spacers to keep the arm in position once the ends have started to bend, it took hours and hours of running to get that far though!

Regular 2.2 wheels and tyres? Although they look good, it raises the chassis even higher!? When I put df-03 wheels and tyres on it already felt like I'd stripped the character from the buggy, too grippy and not much sliding, I only tried it on tarmac though but that was enough to go back to stock tyres and wheels.

If I was trying different wheels etc in the future again I like the look of egress black wheels, the knobbly tyres are not too grippy on tarmac either.........

[ThunderDragonCy 7881]

20 minutes ago, taffer said:

If sleeves keep the blue arm ends from bending in on knocks and crashes, won't that just transfer the shock to the hard black plastic???

I've always resisted doing it, in the past I be gone down the path of using spacers to keep the arm in position once the ends have started to bend, it took hours and hours of running to get that far though!

Regular 2.2 wheels and tyres? Although they look good, it raises the chassis even higher!? When I put df-03 wheels and tyres on it already felt like I'd stripped the character from the buggy, too grippy and not much sliding, I only tried it on tarmac though but that was enough to go back to stock tyres and wheels.

If I was trying different wheels etc in the future again I like the look of egress black wheels, the knobbly tyres are not too grippy on tarmac either.........

I think spacers will help. I haven't had any issues with the stiff TRF arms on my original Dragon, and that's been run (and cartwheeled!) at the track a fair bit. 

Just comes from my own experience with my original Thunder Dragon. I tried the egress wheels but even then i struggled for balance. I find these cars very "on the nose" and trying to get enough rear grip is the thing. I only run on grass and astro, and i have lots of 2.2" tyres for that. If it's a little high, i'll lower it. 

[taffer 948]

Interesting.....I only seem to run on tarmac for the last few years, sometimes off road.

On tarmac I like the fact the wide spike original tyres have less grip and slide around (similar to dirt) , which is then exaggerated as the tyre becomes bald, I wouldn't want it any grippier!?

But it's everyone's driving preferences I suppose!

[ThunderDragonCy 7881]

Dampers. Going full old school. OG narrow shock tower, lower mounting for short shocks. All new parts from spares topped up with a few parts. Still cheaper than black CVAs so that's nice. Build kit spec larger 2 hole pistons, 400cst oil. 

Only nod to more modern thinking is red o rings and green top seals. Should keep them running sweet. 

Old school like the old school. 

Had to use slightly longer spacers on the bottom of the shocks and m3 x 30 screws because of the toe in. In a fit of pique a few years ago i cut down my original rear springs, so they are useless. These are the stiffest silver springs from the DF03 setting spring set. Hopefully they work. I still have my original front spring, but it seems really long, so it's going to generate a lot of preload when fitted. I guess we'll see. 

Original plan for spares box black cva for the front stumbled on my having used up all my shock collars putting cvas on my departed konghead, and now top oil seals. These are bigger than the green ones, so the ones i have don't fit. The ones that so are out of stock everywhere and the shock collar sprues are a bit pricey too. Plan B is that i have bought another set of yellow CVA plastics for a fiver, and i have everything else i need, so full original suspension spec beckons. 

I assembled more of the front having swiped the universals out of my DT03. Original 1989 kit body mount and anti roll bar

I am missing a single kingpin for the steering knuckles, so if anyone has one spare i'll take it! 

Solved the knackered gearcase threads by drilling it out and putting a threaded rod through, then trimming

That's about it. Waiting on some adjusters to finish the steering and for one of my fellow Thundershot fans to hopefully dig out a prop shaft, as i have lost my original. I guess this is parked for a few days then, but not much more to do. 

 

 

[BBenny 12]

Thanks for the link Cy. After a bit of searching here, I came across the idea of inserting the threaded hinge pins in the reverse direction. Seems a reasonable idea and puts less stress on A5. A dab of cyano on the threads and I'll see how we get on. I'll order in the shafts anyway I think.

New problem uncovered is the fractured top holes on the chassis where the front box mounts. Seems a very weak area that gets a fair load of stress. This is a vintage chassis. Any good ideas how to repair that area? 

[ThunderDragonCy 7881]

@BBenny Reversed screwpins could work. Unfortunately those broken tabs are new tub time. You might be able to get creative with some epoxy

[taffer 948]

Using plastex you can shape a mold to recreate the tabs but you need a complete Chassis to get the mould!

[taffer 948]

The screws that go on the tabs front and rear I always add a 3mm washer to spread the load

[BBenny 12]

1 hour ago, ThunderDragonCy said:

@BBenny Reversed screwpins could work. Unfortunately those broken tabs are new tub time. You might be able to get creative with some epoxy

At least new chassis seem to be available. I'm going to try something with steel plates. Had an idea about using the sides of a bicycle chain, will let you know how I get on.

Thanks

[ThunderDragonCy 7881]

Preliminary electronics install. Using the crappy double sided foam tape that never sticks, so i can move if needed! 

Terra Scorcher 2020 manual calls for the esc to be stuck on top of the servo, but i am not that keen on that. I have slid it into the old msc servo slot. It won't get much airflow there though, hence temporary. 

Receiver sticks quite nicely out of the wat on the side of the tub, but that means the aerial won't reach the antenna tube mount on the other side of the tub. Not the end of the world. Again, didn't want to stick it directly on the servo in case of interference. We'll see. If it doesn't work, i'll dig out my old MSC tray and stick the esc up there. 

[taffer 948]

I wouldn't worry too much, my cheapo orange Rx is stuck on my hk servo, 6 years no problems!

[ThunderDragonCy 7881]

Postie brought the last bits today so i could things finishes. Before i start i want to say a massive thank you @taffer  @jonboy1 and @mman2005 for the help and generosity in getting this build done.

Anyway, front shock to kit spec including original spring. Red orings and modern top seal though 

Now that was all done the front end could be installed and steering rods added. Used spare TRF ti 3x32 for the arms and kit threaded rod for the centre link. Hi torque servo and servo saver from another build. Random one-left-of-each TRF adjusters for the centre link too. 

Fitted the bumper and found the servo saver too long. Oops! I found the kit item in my original box and compared and the shortest hole option on the new one was about the same so i relocated the ball stud and trimmed off the rest of the servo saver, re-centred it on the servo. Works perfectly. 

So, i could get it it's wheels

These wheels are off my other Thunder Dragon. Schumacher Full Spike rear, mini spike front. Great for wet winter grass, but has been fun on my other Dragon last week, so thought i would give them a go. I do have a set of wheels for this, but i am going to try a few different tyre options out of the spares box before buying some tyres just for this and gluing the new wheels. 

OG shell. Very cracked, but i think with a bit of lexan offcuts glued on will be just fine. 

Gorgeous day here so came straight up to the park to give it a spin. 

Straight off the bat it's very soft and grip rolls, lots of front end in the usual Thundershot chassis way. Making steady steering inputs helps, but it's ridibg really high at the back. Manual demands preload clips, but given i am running lighter lipo, i took those out and it immediately helped. Ride height was lower and more even and was fun to drive. Having the solid top arms really transforms the stiffness of the suspension, and they still give plenty of camber. If you have a Terra Scorcher rere I might suggest giving it a spin with the solid top arms installed. See how you like it. 

Anyway, i have to tinker, and front seems really soft. I brought my bags of slrings with me so i installed a silver (stiffest) front spring from the DF03 spring set, and added some preload clips to space it out. It doesn't coil bind at full compression, and it's not super stiff as it needed a coupke of extra small preload clips to get it to a reasonable ride height. After this it was really fun to drive. Bit calmer on the front, and once i had driven it a few minutes i checked the steering as everything was at 100%. Tutns out i could dial bqck the dual rate to 80%  and still get full steering lock, and that helped some more, but it still have a slight tendency todig in a roll at full lock. After a bit of experimentation i ended up with 75% on the dual rate, but end points both still 100%. This calms the steering nicely, and stops the digging in at the expense of a bit of turning circle. 

One thing is that the 17t motor was really, really hot at the end of battery. It went really well, but given i am on the smallest 13t pinion, i might need to consider a cheap brushless system. 

Overall i am super happy. It runs so well! Although i don't regret going on my quest with ny other Thunder Dragon, does make realise with some (ok, a lot) more knowledge i wouldn't have done half the mods i have, but that was the whole point of building this. 

 

[Collin 1956]

Nice build. Now as it done, you could start a bid modifying it, no?

[mman2005 443]

1 hour ago, ThunderDragonCy said:

Postie brought the last bits today so i could things finishes. Before i start i want to say a massive thank you @taffer  @jonboy1 and @mman2005 for the help and generosity in getting this build done.

Anyway, front shock to kit spec including original spring. Red orings and modern top seal though 

Now that was all done the front end could be installed and steering rods added. Used spare TRF ti 3x32 for the arms and kit threaded rod for the centre link. Hi torque servo and servo saver from another build. Random one-left-of-each TRF adjusters for the centre link too. 

Fitted the bumper and found the servo saver too long. Oops! I found the kit item in my original box and compared and the shortest hole option on the new one was about the same so i relocated the ball stud and trimmed off the rest of the servo saver, re-centred it on the servo. Works perfectly. 

So, i could get it it's wheels

These wheels are off my other Thunder Dragon. Schumacher Full Spike rear, mini spike front. Great for wet winter grass, but has been fun on my other Dragon last week, so thought i would give them a go. I do have a set of wheels for this, but i am going to try a few different tyre options out of the spares box before buying some tyres just for this and gluing the new wheels. 

OG shell. Very cracked, but i think with a bit of lexan offcuts glued on will be just fine. 

Gorgeous day here so came straight up to the park to give it a spin. 

Straight off the bat it's very soft and grip rolls, lots of front end in the usual Thundershot chassis way. Making steady steering inputs helps, but it's ridibg really high at the back. Manual demands preload clips, but given i am running lighter lipo, i took those out and it immediately helped. Ride height was lower and more even and was fun to drive. Having the solid top arms really transforms the stiffness of the suspension, and they still give plenty of camber. If you have a Terra Scorcher rere I might suggest giving it a spin with the solid top arms installed. See how you like it. 

Anyway, i have to tinker, and front seems really soft. I brought my bags of slrings with me so i installed a silver (stiffest) front spring from the DF03 spring set, and added some preload clips to space it out. It doesn't coil bind at full compression, and it's not super stiff as it needed a coupke of extra small preload clips to get it to a reasonable ride height. After this it was really fun to drive. Bit calmer on the front, and once i had driven it a few minutes i checked the steering as everything was at 100%. Tutns out i could dial bqck the dual rate to 80%  and still get full steering lock, and that helped some more, but it still have a slight tendency todig in a roll at full lock. After a bit of experimentation i ended up with 75% on the dual rate, but end points both still 100%. This calms the steering nicely, and stops the digging in at the expense of a bit of turning circle. 

One thing is that the 17t motor was really, really hot at the end of battery. It went really well, but given i am on the smallest 13t pinion, i might need to consider a cheap brushless system. 

Overall i am super happy. It runs so well! Although i don't regret going on my quest with ny other Thunder Dragon, does make realise with some (ok, a lot) more knowledge i wouldn't have done half the mods i have, but that was the whole point of building this. 

 

Do you think switching to dual shock front would help with handling Cy? 

[ALEXKYRIAK 1046]

Wonderful build and thread, Sir!  thanks for sharing. 

[ThunderDragonCy 7881]

1 hour ago, mman2005 said:

Do you think switching to dual shock front would help with handling Cy? 

It might, but it's not far off. Going to try much heavier oil. One shock effectively doing the job of two, so some more damping probably good. Front is noticably quicker than rear despite running same pistons and 400cst oil as the rear. I'd like to get it running sweetly with the monoshock. 

[ThunderDragonCy 7881]

Alternative shell whilst I patch up the Thunder Dragon? 

 

[Collin 1956]

Much better!

[mman2005 443]

17 hours ago, ThunderDragonCy said:

Alternative shell whilst I patch up the Thunder Dragon? 

 

Looks good! Where did you get the shell from? Is it the re-re one?

[ThunderDragonCy 7881]

1 hour ago, mman2005 said:

Looks good! Where did you get the shell from? Is it the re-re one?

Its Team Blue Groove with MCI custom colour decals. I bought it for my Grasshopper 2 Ultra G, but the fit is a bit awkward. Does sit nicely on this. 

[mman2005 443]

1 hour ago, ThunderDragonCy said:

Its Team Blue Groove with MCI custom colour decals. I bought it for my Grasshopper 2 Ultra G, but the fit is a bit awkward. Does sit nicely on this. 

Agree, does sit nice. 👍