M-05 & M-08 duo rebuild/build

[Tamiyastef 1607]

Next up are the rear lower suspension arms, also using the TL-01 parts obviously 

 

The attachment for the stabilizer already installed and the whole rear end bolted together.

Installing the rear dampers with only the BB1 step screws and F4 spacers

as I will be using the carbon damper stay that includes ball connectors

That's done

[Tamiyastef 1607]

We got to the electronics part of the build and will be using what I think are the last blue parts

The manual shows the general electronics installation similar in most Tamiya manuals

 

And apparently there has been made another change to the chassis before the change to the version 2 chassis

  

During the original build I removed (cut off) the part of the ESC "tray" where you should screw the on/off switch so there's enough space for the brushless ESC. Note it isn't taped to the tray yet.

With this the M-05 build is almost finished (just the rear freewheeling axles, the wheels, body posts and body to go) and time get my focus back on the M-08.

[Tamiyastef 1607]

Opening screw bag C on the M-08 build has us officially passed the half way point in the chassis build and gives us the first steps on the front end

Front suspension arms

 

and mounting them to the chassis.

Already installing the base for the steering assembly before starting on the front axles.

All these shims on the axles   made me take another look at the left side of the manual  

This made me notice something I hadn't realised before. Each screw bag (for example screw bag C) contains several smaller bags with screws. Apparently Tamiya has them kind of labelled but don't put it on the bags... All items "named" MA come from the same small bag, this is the same for MB, MC,... If you keep the items from the same small bag together (and don't throw all items from screw bag C together in one tray) this makes it easy for knowing which (sometimes very similar) part exactly you need. Especially with all the almost identical shims this system makes life easier.

If you are aware of it. 

I wonder why Tamiya doesnt label the small bags C1, C2, C3,... 

 

Now step 24 starts with making "two of these" but then splits up between left and right.

If you didn't drill all the 2,5mm holes at once the first time they asked you to drill one, it's time to get the dril out again for the C-hubs in step 25 and 26.

and after that there's some fiddling required with the C6 parts... let's say we're not friends  but I didn't bother gluing them together so that part is on me I guess... First for the left, later for the right side.

Next is attaching them on the chassis

  

[Tamiyastef 1607]

Next up: the electronics page with (believe or not) my first Tamiya High Torque servo saver. There's probably a very simple system for this but let me say those spring steel rings kept me busy for a while...

but it looks all okay

untill I check the dimensions for the servo mentionned in the manual... dimensions for mine are the ones written in pencil...

decided to try and build ahead, maybe the extra height doesnt interfere with anything later on. Or I need to take another look at that direct steering video on youtube. Used some spacers to mount the servo.

 

On to the bellcranck

So nice it's fully ball raced , now getting it on the chassis and get the links installed

Jumped a few steps forward and did a "dry fit" of the parts that gets the pivot points of the bellcranck system secured,

Looks great IMO allthough completely different from the M-05...

Off course the stabilizer is still missing on the front of the M-08 but steering left and right reveals another difference 

 

Steering is (very) limited, especially compared with the steering on the M-05

 

Take into account the steering on the M-05 is more limited now than it was before. The version 2 chassis moves the motor more to the middle and makes the steering knuckle hit the gearbox earlier than on the previous version.

 

This limited steering on the M-08 is more than likely all down to the height of the "low" profile servo that isn't all that "low" it seems. Checking some online stores the dimensions Tamiya asks for are never in the descriptions... so buying another "low" profile servo may turn out to be another (costly) bad buy. I think I'll have to look deeper into the "direct" steering solution.

Bummer. I had my mind set on comparing the stock (with exception of the stabilizers) M-08 with an all hopped-up M-05. Not so keen on making such a drastic change...  and don't make use of this beautiful precision made and ball raced bellcranck in reinforced plastic. 

[Pylon80 1307]

1 hour ago, Tamiyastef said:

This limited steering on the M-08 is more than likely all down to the height of the "low" profile servo that isn't all that "low" it seems.

I can't quite see which part is limiting the steering. In any case, if you found that it was due to the servo being too high compared to the bellcrank, is there a way you could simply insert the required amount of spacer under a ball nut, i.e. under where MA10 meets part K2? (sorry I took a nice screen shot and annotated it but I got the usual "failure to upload" we have been getting over the past 2 weeks  ).

 

[Re-Bugged 9310]

Not wanting to highjack a thread here my friend , but I’ve just had a look at my M08, (not the R though) and from what I can see the steering has a bit more angle..

 

The only reason I can tell is that you had your concerns about the height of the Servo? It looks to me from your photos that the steering bridge is hitting the front two screws stopping it going any further.
On full lock on mine the bridge clears those screws.

Maybe take those screws out temporarily to see if you get any more angle. If you do using countersunk or something with a flatter head might work. 

[Tamiyastef 1607]

@Pylon80 this is a picture where you can see it is indeed the "bridge" of the bellcranck that doesn't clear the screws holding the servo because the servo is too high.

When I just leave the spacer in place (about the same thickness the lip on a servo is) you can see the bridge clears it.

It is just the grub screws that limit the steering then

@Re-Bugged you're completly right about the height of the servo being the problem here (btw mine's not an R either)

Before spending €50,00+ on another servo I'm gonna try to see if I can get the bridge of the bellcranck a little higher and use countersunk screws to mount the servo (or at least the two screws in front that is)

[Pylon80 1307]

2 hours ago, Tamiyastef said:

@Pylon80 this is a picture where you can see it is indeed the "bridge" of the bellcranck that doesn't clear the screws holding the servo because the servo is too high.

When I just leave the spacer in place (about the same thickness the lip on a servo is) you can see the bridge clears it.

It is just the grub screws that limit the steering then

@Re-Bugged you're completly right about the height of the servo being the problem here (btw mine's not an R either)

Before spending €50,00+ on another servo I'm gonna try to see if I canget the bridge of the bellcranck a little higher and use countersunk screws to mount the servo (or at least the two screws in front that is)

Oh I see it now. That's really annoying, Tamiya 😅 It sounds like you're headed in the right direction now. The CS screws would be the easiest solution (do not overtighten them else it might crack the case 😕). If you raise the bridge, you will probably need an equivalent amount of shims on the knuckles to avoid affecting bump steer (easy to do). Another solution could also be to remove material from under the bridge, if you feel like hacking a brand new kit 🫣

This discussion is exactly what makes these threads so useful.

[Tamiyastef 1607]

15 minutes ago, Pylon80 said:

This discussion is exactly what makes these threads so useful.

Yes indeed!

[Tamiyastef 1607]

Worked out a temporary solution, countersunk the screw holes in the servo lip and removed that little protrusion in the middle of that lip.

Put some washers between the bell crank arms and the bridge and backed of the pivot screws so their end is level with the bridge and not protruding underneath.

Steering is still limited somewhat (there remains a small gap of 0,5 to 1 mm between the grub screws and the c-hubs) but much beter IMO, see before and after pictures below.

 

 

This will have to do untill I can convince the wife I need (and deserve) another RC car, charger, some spare parts and a low profile servo which have been parked in my shopping cart for far too long now 

This also means I can go to the next step which needs bag D to be opened  This is always feeling very double to me. The excitement to see the end result on the one side and a bit of disappointment and sadness on the other because I'm done building. 

[Pylon80 1307]

On 9/9/2023 at 2:54 PM, Tamiyastef said:

Worked out a temporary solution, countersunk the screw holes in the servo lip and removed that little protrusion inthe middle of that lip.

That looks nicely done.

On 9/9/2023 at 2:54 PM, Tamiyastef said:

backed of the pivot screws so their end is level with the bridge and not protruding underneath.

I think you backed off the ball studs so that the adjusters wouldn't hit the bridge at full droop? If you want to be able to tighten them properly and have them symmetrical too you can add a spacer under the heads (53539 would be perfect).

On 9/9/2023 at 2:54 PM, Tamiyastef said:

there remains a small gap of 0,5 to 1 mm between the grub screws and the c-hubs

The angle looks alright. It sure would be cool to be able to use the grub screws as they are a really neat feature. If you can measure the steering angle I think anything above 20deg on the inside wheel will be sufficient. If you don't have a setup station, a straight edge resting on the wheel will allow you to draw the angles on a sheet of paper 👌

[Tamiyastef 1607]

6 hours ago, Pylon80 said:

That looks nicely done

Thank you

 

6 hours ago, Pylon80 said:

ball studs

indeed, not the pivot screws but the ball studs and thanks for the suggestion of 53539, will get a set of those.

 

As for the steering angle; will see how it goes once it's up and running. If I feel it can't take the sharp postal racing corners well enough I'll take another look at it.

[cstorckiii 153]

On 9/8/2023 at 2:24 PM, Tamiyastef said:

Next up: the electronics page with (believe or not) my first Tamiya High Torque servo saver. There's probably a very simple system for this but let me say those spring steel rings kept me busy for a while...

but it looks all okay

untill I check the dimensions for the servo mentionned in the manual... dimensions for mine are the ones written in pencil...

decided to try and build ahead, maybe the extra height doesnt interfere with anything later on. Or I need to take another look at that direct steering video on youtube. Used some spacers to mount the servo.

 

On to the bellcranck

So nice it's fully ball raced , now getting it on the chassis and get the links installed

Jumped a few steps forward and did a "dry fit" of the parts that gets the pivot points of the bellcranck system secured,

Looks great IMO allthough completely different from teh M-05...

Off course the stabilizer is still missing on the front of the M-08 but steering left and right reveals another difference 

 

Steering is (very) limited, especially compared with the steering on the M-05

 

Take into account the steering on the M-05 is more limited now than it was before. The version 2 chassis moves the motor more to the middle and makes the steering knuckle hit the gearbox earlier than on the previous version.

 

This limited steering on the M-08 is more than likely all down to the height of the "low" profile servo that isn't all that "low" it seems. Checking some online stores the dimensions Tamiya asks for are never in the descriptions... so buying another "low" profile servo may turn out to be another (costly) bad buy. I think I'll have to look deeper into the "direct" steering solution.

Bummer. I had my mind set on comparing the stock (with exception of the stabilizers) M-08 with an all hopped-up M-05. Not so keen on making such a drastic change...  and don't make use of this beautiful precision made and ball raced bellcranck in reinforced plastic. 

The SPT 4412 servo fits well... and they're cheap.

[Tamiyastef 1607]

 

These are the dimensions given on the SPT site, I have problems with the Carson that's 19 mm where the SPT is 19,8 mm and the M-08 manual asks for 17 mm or less...

Have you fitted one of these in an M-08?

[cstorckiii 153]

Yes, I have. That's how I know it fits.  And it's inexpensive enough ($20 USD, $9 USD at Aliexpress) that I use it in everything.

[Tamiyastef 1607]

So dimensions given on SPT site are incorrect? Or am I missing something else?

[cstorckiii 153]

I honestly don't know. I'll dig into my M08 after work and find out.

[cstorckiii 153]

Well, don’t listen to me. I just checked my M08 and evidently have the same problem and didn’t know. 

[Tamiyastef 1607]

@cstorckiii Did you notice anything of the limited steering while driving it?

That is if you have driven it or is it a shelfer?

I wonder if I would have noticed it myself if I wasn't doing a build thread.

[cstorckiii 153]

I didn't notice anything off with the steering, but I haven't driven it much. And I spent about an hour last night fixing the issue.

[Tamiyastef 1607]

16 minutes ago, cstorckiii said:

fixing the issue.

Which route did you go? Other servo, spacers, direct steering? 

[cstorckiii 153]

Issue 1: the screws. My M08 kit came with a couple of extra super thin head screws ( MC 4), so I used those at the front of the servo.

Issue 2:  the servo itself. With the servo sitting higher than it should the steering arms at the front bearings hit the front corners of the mounting tab on the servo. I removed the servo and rounded the front corners down with my Dremel and shoved the servo as far back as it would go. It swings lock to lock now.

[Tamiyastef 1607]

On 9/11/2023 at 3:19 AM, Pylon80 said:

That looks nicely done.

Looks even nicer now, thanks again for mentioning the 53539.

 

[Tamiyastef 1607]

Next step on the M-08 (number 32) not only requires screw bag D (the last one ) to be opened up but also which wheelbase will be used. I'll be building the L variant with the 239mm wheelbase. While this is an "M" chassis it has a longer wheelbase then the TA-03RS (IIRC 237mm) which is considered a touring car  

The S/M/L version you choose determine where these posts and bridges go on the two chassis' halves

Posts installed, and the bridges too

 

Next up is the front damper stay and attach it to the front bulkhead

For the time being I skip the body post installation. On the left of the manual the front stabilizer is mentionned

so time to get the specific manual and parts for that:

and get it istalled

In the same step the steering rod is made

Installation of the front bulkhead and the steering rod

 

Electronics will be for tomorrow...

[Tamiyastef 1607]

Back to the workbench and the M-05. I used some of the 53539 spacers on the M-05 as well to replace the split F4 parts and the black damper spacers I first used to replace them...

I can't have too much blue on this M-05 so I changed the spacers behind the shocks to blue as well