Keyword

TOPIC:

Dan's first Hotshot restoration 5 years 8 months ago #50940


Well, I finally got to tearing into the first of the two Hotshots I picked up a few weeks back. This is my first Tamiya, and also my first non bucket/open body RC. To be honest, I only found my way into RC via two Traxxas Stampedes at a yard sale barely 2 months ago! But a bottom to top rebuild of those two trucks boosted my confidence just enough to dive right in on these beauties.

Given the base materials I'm working with, and the fact that I am replacing motor and speedie at the very least, this is not going to be a bone stock refurb. If this needs to move to another thread, I completely understand!

The first task was removing the bottom tub, and front and rear gear boxes. While I have the original manual, I started in on this without it, and wound up removing suspension along the way. No big deal, as I made sure to track my steps in photos, and labeled all hardware in plastic bags for re-assembly. Overall, things looked pretty good so far, and a good cleaning of plastic parts, and polishing of metal, worked wonders on visual appeal.

Drive shaft before cleaning


Drive shaft after cleaning with Blue Magic polish


Opened up both cases and was relieved to see that all gears are in good shape. Looks like the previous owner had applied grease liberally, and so a good cleansing of gears and cases with 95% rubbing alcohol brought them back to ground 0, and I applied a thin coating of lithium grease all around. Unfortunately, I did not take photos of the clean, reassembled interior.


Next up, I gave all plastic parts a thorough inspection to assess damage. Sure enough, one of the rear uni-shock brackets is cracked nearly all the way through. It looks like after the original owner upgraded to dual shocks, he tried to fill that gap with a rubber grommet that didn't quite span the distance, and after tightening one too many turns, the bracket finally gave. I superglued as best I can for now, and used two bearings and a piece of plastic as a brace between the two sides in the hopes that I'll get a little more life out of this before it goes altogether. Needless to say, I have a parts tree with the cases on the way for when it goes!

Please Log in to join the conversation.

Dan's first Hotshot restoration 5 years 8 months ago #50941

Final step for the day, I cleaned all plastic parts on the suspension arms, polished the drive shafts, polished and greased the hinge pins, and reassembled. The front shock was surprisingly close to topped off with oil, but I went ahead and changed the shock oil while I was in there and cleaned up the shock tubes and spring.


The body paint is fair, and I'm going to paint a new shell when it comes. For now, I hit the shell and wing with Tamiya PS3 spraypaint to fill in the chipped parts, and the color doesn't quite match what he brushed on 30+ years ago. I'll start from scratch on the new one when it comes, and thankfully the previous owner did not use the original decals, so I'll have those to work with when applying the finishing touches.



Here's the cleaned up frame and suspension so far. Next steps are to install the RZ Super Stock motor (waiting on a new motor plate/mount), and load up the tub with receiver and ESC. I'm installing a Hobbywing Quicrun Crawler Brushed ESC, which I have in one of my trucks and I really like, and using a Spektrum DX5C controller/receiver set up. Hope to update the thread with progress later this week!

Please Log in to join the conversation.

Dan's first Hotshot restoration 5 years 8 months ago #50942

I should also add that while there were some ball bearings used in the original build, I still replaced all bearings with brand new sealed bearings. I'm REALLY looking forward to driving this. I imagine I will eventually add dual shocks to the front, and maybe try to figure a way to minimize bump steer (does that bump steer eliminator actually work?? - there's a Parma brand locally that I'm tempted to buy). I do plan on driving this with some regularity.

Please Log in to join the conversation.

Dan's first Hotshot restoration 5 years 8 months ago #50943

You already have some nice ally option parts. So and nice shocks. Maybe better than original setup. It should be a nice runner. I don't think that you need a dual shocks front suspension setup

Please Log in to join the conversation.

Dan's first Hotshot restoration 5 years 8 months ago #50944

Nice restoration and upgrades. Looking forward to see this thing in action :y: :cheer:
Signature now gets correct formatting if you edit it in your Profile. Use normal BBcode if you want.
www.tamiyabase.com was formatted automatically.

Please Log in to join the conversation.

Dan's first Hotshot restoration 5 years 8 months ago #50957

Thanks guys! Pulled a motor plate and motor shims from my red Shot (were missing on the blue Shot) and planning on getting back on this build tonight. I just soldered a nimh battery connector to my Hobbywing ESC, and am off to the store for bullet plugs for the motor.

Still waiting on a new body, tires and wheels, and a few other items to get it looking tip top, but I just may have this baby put back together with the parts I have on hand for a test run later tonight! I'll be sure to post pics, as well as an "in action" video once completed.

-Dan
The following user(s) Liked this: larbut, stingray-63, Al

Please Log in to join the conversation.

Dan's first Hotshot restoration - UPDATES AND QUESTIONS! 5 years 8 months ago #50960

I unfortunately was only able to spend about 30 minutes on the Hotshot last night, but managed to cross a few small tasks off the checklist.

I mounted both front and rear suspension arms and gearboxes on the body, along with the driveshaft, battery brackets, front stabilizer bar, and motor.


Quick question on mounting the motor: anyone else bypass using the motor spacer brackets? I'm running a 15t pinion (until the 13t arrives), and following the diagram in the manual of 2 on each side of the adjustment screw, I'm unable to fit the pinion against the drive gear sufficiently to turn the gears. I've only adjusted pinion/drive gears on my Traxxas trucks which don't rely on brackets. But you have complete visual and physical access to those gears and are able to make an accurate fitting right there. With this closed gear box, I basically fit the two gears together by feel, just barely backing off in the hopes of not fitting too tightly. Anyone else do this?

I don't have bullet leads on my ESC yet, but did hook the motor up to the ESC one of my trucks, and the motor and gears all seem to function well. I say "seem" as while they turn as they should, I'm not used to the running noises of this car, and am not sure if the gears and drive shaft are turning as freely as they should from the "whirring" noise I'm hearing. It sounds like there could be some resistance or friction, but maybe this is all within the range of normal. I'm used to my trucks where after hitting the throttle and then resting in neutral the wheels spin freely. Not so with the Hotshot, as the wheel mounts come to a halt as soon as I let off the throttle.

Here's a video of it in action and I'd love to hear another, more experienced user's opinion:

<a href="
" target="_blank">Hotshot Video
Attachments:

Please Log in to join the conversation.

Last edit: by danrighton.

Dan's first Hotshot restoration 5 years 8 months ago #50967

No wheels on thr car there, so no inertia to keep things spinning ... but things do sound tight. I would suspect the motor pinion - either it's in the wrong position on the shaft (so face is rubbing on something else), or the mesh is too tight (check the tooth count & the number of bars/motor position, IIRC that motor has more than one pair of mount screws too, so something else to go wrong ... 4th possibility is are you using a 32dp pinion rather than 0.8 mod?

:)

Please Log in to join the conversation.

Dan's first Hotshot restoration 5 years 8 months ago #50973

No wheels on thr car there, so no inertia to keep things spinning ... but things do sound tight.
:)


I think that's all it was...just had the pinion and drive gear teeth too close. I don't know what I did wrong yesterday, but I just sat down and used the mounting spacers again with the 15T and all sounds MUCH quieter...or at least "free-er" if that makes sense. No more round squeaking/squealing.

I also was pouring over the manual again and realized there are urethane bushings missing in the gearbox joints. Ordering from Tamiya today. Not sure if I'll be able to wait to test this out though should I complete the build before they arrive!
The following user(s) Liked this: Gripper107

Please Log in to join the conversation.

Dan's first Hotshot restoration 5 years 8 months ago #51031

OK, finally received some much needed bits to get the car running again. I was having a heck of a time finding 3.5mm female bullet connectors that fit the motor plugs snug, and so finally just settled on soldering new gold connectors on both motor and ESC in order to have a tight match.


With that, I mounted the Hobbywing ESC, Spektrum receiver, and a new Traxxas 2018 servo for steering inside the belly of the beast. I've never been much for cable management, and you really have to get crafty in this tight little space. I can't imagine trying to shove the old MSC back in! The little on/off button fits just right underneath the body.


I couldn't wait for the new body + wing, gold wheels and rubber to arrive, and so slapped the oldies on in order to give this a test run. Wow, does this thing move with an RZ Super Stock loaded! I'm a little concerned, as the motor gets hot after only a few minutes of running. I'm thinking of switching out the 15t for a 13t to lower my top end, which would in theory cut down on heat a little, right?


I have a couple of questions too. One is, in building this car out, I've needed to pull some parts off my red 'Shot. One of them is a steering arm shaft and adjusters - parts MT1, MP3 and MP4 in the new manual. I'm having trouble finding these online (or at least spelled out as such). Are these in a parts bag by chance? I've searched for "M parts" with no luck...

Also, I noticed in the Re Re there is an inclusion of polyurethane bushings for the drive train cups, which were not included in the original kit (which this 'Shot is). Should I throw some in? Does it help reduce wear and friction significantly? This is what I'm talking about - part MD2. I ordered some just in case. Figure they'll come in handy down the road if not now.


I'll post a video of it running next!
The following user(s) Liked this: stingray-63, Al

Please Log in to join the conversation.

Last edit: by danrighton.
Moderators: caprinutstingray-63AndyAus
Time to create page: 0.199 seconds
Cookies are required to make this site work. If you continue to use this site you permit us to use cookies.