MST TCR-M speed build for model show

[alvinlwh]

I discovered yesterday I have a new Aliexpress 'special' Mini body lying around thar I can build for the upcomingb local model show. It was really cheap (<£10 iirc) I think i bought it to test AE's quality. I also have a part MST TCR-M chassis unbuilt, perfectly for this body. I have a model club meeting and I have to rush to have at least something decently part finished to show and tell. 

Tearing straight into it, as I said this kit is not 100% complete. It's drive train were used on another TCR chassis to make it a twin motor and 4WD).

[Alex97]

These £10 shells are very thin and not really worth painting in my option. Your better off getting the L&L one. 

[alvinlwh]

I was actually further along rhe build than that first post suggest. However, I built so late into the night that when I tried to make the above post, I was already drifting off and typing gubbish. 

Anyhow, after a night's sleep, here is a proper progress report.

This chassis kit was bought a while back to use as a donor for parts to convert another TCR-M that I have in a twin motor 4WD, so all it's drivetrain parts had been used. While replacement parts are available, they come up to over half a dozen part numbers. Instead I bought the upgraded ball diff set, which then cuts the number of parts needed to just 4.

The diff screw, trust bearing washers, trust bearing balls, will all count as different parts if ordered separately. It had been a while since I built a ball diff trust bearings and they are tiny!

The upgraded diff is more difficult to build compared to the stock, luckily I have a spare pair of hands in helping me get the balls in.

The diff mounted onto the front as this will be a FF build, it's a Mini after all!

And the rear bulkheads mounted on the 210mm position.

Now I need to get the out drives from AT, which consists of 3 part numbers.

[alvinlwh]

11 hours ago, Alex97 said:

These £10 shells are very thin and not really worth painting in my option. Your better off getting the L&L one. 

They way I see it, nothing will be a waste when it comes to painting models. I had bought really old (and cheap) Tamiya and Airfix kits just for practicing painting. Their quality are crap and more likely than not, I set fire to them after I am done, they still served their purpose as a cheap canvas to try out new painting methods  

[Gebbly]

An interesting project. I like farmer Giles passing by in the background on his tractor  Looks really useful having a spare pair of hands especially smaller hands for the fiddly bits. How do you find the quality of components and clarity of the instructions from MST compared with Tamiya builds?

[alvinlwh]

43 minutes ago, Gebbly said:

How do you find the quality of components and clarity of the instructions from MST compared with Tamiya builds?

Components - great. This is a very cheap kit yet it comes as standard, bearings, fiberglass chassis deck and high strength plastic as standard. It does not have oil shocks as it is not that kind of suspension. 

Instructions - not so good. TBH, I doubt anyone can beat Tamiya on this one. 

The instruction for the ball diff is particularly confusing. This is the stock one.

The upgraded metal one's Instructions can be seen up top. I had built the diff wrong more than once.

PS - the WR-02G seen in the background is the one I originally built for the model show. Just happened to find this Mini in my store and decided to build it too.

[alvinlwh]

Speeding on with the speed build.

Gathered the electronics that will be used in this, a Tamiya 380ST previously used in another TCR-M, JX HV high speed servo and an ESC that can support thr HV servo.

So in installed the motor, bumpers, battery holder, rear wheel hubs (front has to wait till the universals arrived).

Due to the confusing instructions, my rear bulkhead was in the wrong position and things will not go together correctly. I had to relocate it correctly.

Front

I used some 2.5mm spacer between the motor and mount to allow for a bit of space for more cooling. These 380STs can run very hot.

Rear

While the battery cage is set up for standard at the moment, I may go shorty eventually. The problem is my only shorty battery is puffed up and ready to blow.

[alvinlwh]

As for the body. I had done the base color. I was trying to decide on which color for the car as there will be a flag on the roof. I do not want the usual red, blue or racing green. This left me with black or white, which neither appeal to me. Silver? Maybe. How about gold? Bingo! There is another reason for going for gold (literally) which will be revealed later on.

Also, my color selection is restricted by the paint I have on hand as I do not have time to gather and wait for an order from TTM. What I will be using will be Vallejo paint, not my favourite but they claimed to be suitable for PC bodies.

Lastly, on top of my original response to @Alex97, I am trying out a new painting method full scale first time. If it works, great. If not, I rather to be wasting a £10 shell than a £30 one.

So here is the shell with the base color on. I painted the grills and bumper on the inside but I am getting ahead of myself here.

The quality of the roof of this cheap shell is quite rough, but it don't matter as I am trying something new. It seems fine elsewhere.

To get to this stage, I first primed the inside with clear plastic primer, the same type of primer that yoy will use to prime upvc drain pipes before painting them with anything else. A professional (1:1) painter in my club gave me this tip. The primer allows paints other than PS to 'grip' to the PC. Of course a known alternative is Tamiya PS-55, but ordinary plastic primer is much cheaper.

Then I use a variety of paint markers and X/XF paint to do the grills. Then the actual gold, which I used Vallejo Game Air Polished Gold, something that I had used before on a Lunchbox Mini. Finally, it is backed by Vallejo Premium (suitable for RC) Black.

Next is masking the roof for outside painting. Also, the roof PC will be primed by the clear plastic primer.

3 coats were applied and as can be seen, it drys completely clear.

[alvinlwh]

Model club meeting tomorrow, so I am cracking in with thr build. The closer I can get to completion, the better.

First is getting the servo in. Connected up the electronics to test the motor and centre the servo. The RX is a temporary one as I have a HotRC RX with gyro coming in.

I do not really like to cut tabs off servos...

Installed with servo saver and steering arms. Normally these days I do away with servo savers but the horns supplied with the servo will not work here.

[alvinlwh]

Then the body. First attempt was a disaster. After using the clear plastic primer, I sprayed on Vallejo White Primer. Mecha Color is claimed to be tougher, able to withstand handling.

Well, it just does not 'stick'. After letting it dry for hours, I proceed to start with the masking. Pretty soon the primer stated coming off in sheets. There is zero bonding with the plastic primer. So I just sanded everything off, which also roughen up the surface for the next attempt to have a better key. At this point, I noticed that the plastic primer is still attached to the PC as I am sanding it off. This is actually good to know. After sanding I sprayed another 2 coats of plastic primer.

Then to prime for the final coat, I used Mr White Surfacer 1000 as the base coat. I have to use white as I will be working with yellow, which will be horrible over anything other than white.

I also did some calculations to scale the flag design correctly to the roof.

Finally, I spray the first coat, which is the yellow part of the design. As yellow cannot be over anything else, it has to go down first.

The good thing about the failure of the Vallejo paint is that I am forced to use Mr Color, a paint that I am more comfortable with and is easier to work with.

[alvinlwh]

Rushing forwards with the paint job. The first 2 color went down and survived the masking tape test fine.

Now I am going to let it dry out properly (I only waited an hour before masking the yellow) before masking for the last color. Don't want to risk messing up at this point.

[alvinlwh]

Masked up for the last color.

And sprayed on the last color.

Roof mask removed.

And clear coated. I may do another one for better protection.

 

[rich_f]

What's the reasoning for painting the body on the inside but the roof on the outside?

[alvinlwh]

1 hour ago, rich_f said:

What's the reasoning for painting the body on the inside but the roof on the outside?

Speed plus ease of masking. Also want to test the tip I got from someone else about using the clear plastic primer.

Thing is this shell was a cheap shell, really bought for the purpose of experimentation. 

[alvinlwh]

Removed the body masking.

The Vallejo on the inside did poorly against a bit of masking tape that touched it.

Really annoyed but it's not the first time.

[markbt73]

Looks great for a cheap body shell!

Out of curiosity, what is the reasoning behind the primer? I use Vallejo paint on polycarbonate all the time, and I never prime. I just wash the body carefully. I've never had a problem with adhesion, as long as I let the paint dry fully (2-3 days) before removing the masking.

[alvinlwh]

2 hours ago, markbt73 said:

Looks great for a cheap body shell!

Out of curiosity, what is the reasoning behind the primer? I use Vallejo paint on polycarbonate all the time, and I never prime. I just wash the body carefully. I've never had a problem with adhesion, as long as I let the paint dry fully (2-3 days) before removing the masking.

The primer is to try and improve adhesion. In fact, when possible, I use Vallejo primer as they come in white, black, silver, and a few other colors. However, I never find Vallejo to be good for any surface, they just peal off in sheets and have very poor scratch resistance. I had battery wires rubbing off Vallejo paint in the past. In fact it was white Vallejo primer that just pealed off completely from the roof. Their primer does not stay on top of primed surface! 🤷‍♂️🤣

Now back to the primer, while Vallejo primer does not stick, I have other modelling paint that I want to try. And they stick well enough.

One thing is, it is very difficult for me to get PS paints where I am. There is only one retailer that is willing to ship to me, and I need to gather an order of £45 to get them to ship. However I have nearly the whole catalogue of Mr Color and Tamiya Acrylic paint. So if the primer worked (which it seem to in this experiment), there is no need for me to use expensive PSon my PC shells anymore since i have a limitless color selection right here already.

A side note, the Mr Color were masked over after an hour of warm air drying and mask removed after about a day of warm air drying. No pealing.

[alvinlwh]

Some printable vinyl arrived so on with the logos.

I started out painting the main body gold without a plan or reason, and it turned out to be the right choice!

[alvinlwh]

Installed the electronics. The RX is a HotRC one with gyro. This chassis drives really well with a gyro.

Pulled the 'body shocks' off another TCR-M I have as they will not work because I converted that one to 225mm WB.

[alvinlwh]

Local holiday over here today and just received a delivery from AT with the bits needed to build the universals.

Shame that 3 separate items are required to build such a tiny part, MST should just package it up as one item, same as what they did with the ball diff set.

Installed to the front and instead of the brake discs, I am using the free metal hex I got with each AT order. Reason is I will not be using the kit wheels and tyres, which are too big for a Mini.

Took it for a trimming run.

And that's the TCR-M FF chassis completed.

Next to finish up the shell.

[Andreas W]

Another nice MST TCR-build of yours. How is it compared with,  let's say,  an M-05? It must be lighter I suppose.

 

Can I ask which wheels you are running? From design they look like Ride. The thing is I bought a lot of Ride 60D tyres this winter to find out that the inner diameter is bigger than normal M-chassis wheels. Meaning Tamiya or Carten wheels would not seat inside the tyres. I have got more Ride wheels now, so no crisis,  but it would be nice to have other options. If you are running normal 55D tyres your wheels are the normal Ø=47mm on the other hand. Maybe they are the same as the 10 spoke Carten or Phat Bodies. 

[alvinlwh]

3 hours ago, Andreas W said:

Another nice MST TCR-build of yours. How is it compared with,  let's say,  an M-05? It must be lighter I suppose.

 

Can I ask which wheels you are running? From design they look like Ride. The thing is I bought a lot of Ride 60D tyres this winter to find out that the inner diameter is bigger than normal M-chassis wheels. Meaning Tamiya or Carten wheels would not seat inside the tyres. I have got more Ride wheels now, so no crisis,  but it would be nice to have other options. If you are running normal 55D tyres your wheels are the normal Ø=47mm on the other hand. Maybe they are the same as the 10 spoke Carten or Phat Bodies. 

The wheels are just some cheap Aliexpress I use for rough running.

https://www.aliexpress.com/item/1005004846345020.html?spm=a2g0o.productlist.main.69.17c86g5t6g5t5G&algo_pvid=2017f863-6622-4840-b628-56f96ea10d5c&algo_exp_id=2017f863-6622-4840-b628-56f96ea10d5c-34&pdp_npi=4%40dis!GBP!11.58!7.76!!!14.34!9.61!%402103895417231921602014871e2674!12000030722060328!sea!UK!1875226388!X&curPageLogUid=pdsJmNvA565O&utparam-url=scene%3Asearch|query_from%3A

I think they are slightly bigger than 55D but are still smaller than the kit ones, which are bigger than 60D.

I don't think it can be compared to a M-05 directly as it is lighter (like you said), far lower ground clearance, simple suspension and steering setup. Also, this is a true FF while the M-05 is a FMF. But back to the TCR, it actually drives great for such a simple chassis, very sharp.

Main reason I got a second one of this chassis is that it is a cheap chassis to set a body on. However this build turns out to be a little more expensive as I had stolen some bits out for the twin motor 4WD TCR-M and also the alum diff upgrade (to replace the stolen diff).

[Verskis]

Good looking body shell!

I am not familiar with the TCR-M at all. Seems interesting, is the suspension a bit like McPherson strut? And what do the bigger shocks laying on the chassis do?

 

I am also wondering, how does the Mini shell fit with the front bumper? Seems like it would be impossible to run the bumper under the shell, surely there is no space for that?

[alvinlwh]

3 hours ago, Verskis said:

is the suspension a bit like McPherson strut? And what do the bigger shocks laying on the chassis do?

I am also wondering, how does the Mini shell fit with the front bumper? Seems like it would be impossible to run the bumper under the shell, surely there is no space for that?

The suspension is indeed MacPherson strut suspension, without damper. The 'body shocks' is to stiffen the body a bit as this does not have a top deck like most other chassis, so it can bend, unlike this TA-02 I have which is very stiff. 

However, does those shocks do anything at all? Well, I am not sure. I have them spare, they make the chassis looks good, so they go on. I had someone telling me they need to be really stiff to do anything and 2 tie rods will do the job better. Maybe so. Which is why on my 225 one, I used massive big bores with stiff springs and a massive amount of preload dialled in.

You are right about the bumper. I will have to go without. Many 210mm bodies cannot fit onto a bumper unfortunately. 

[alvinlwh]

Final bits came to allow me to finish the build, Contact foam 45sh mini tyres.

Problem is even when using 55D M-chassis tyres, there is still body rub. These foam ones are 52.5mm. Above are L-R: Contact 52.5mm, Aliexpress 55mm and MST stock 60mm.

There is no body rub now but because I opened the wheel wells up a little to try and fit the 55Ds and now they are looking too wide. Since this body only cost just over £10, I am planning to get another one to try again.