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Dadio wrote: ↑Sun Jul 10, 2022 1:40 pm @silvertriple ,I really was joking

You didn't saw any of the smileys in my answer?

Added upper arms now. They are tie rods, with rod ends. I'll probably have to print the rod ends as the part of those I got have been cut too short.


Remains Shocks, servo saver, tires (rims were done first, but I still have the tires to do)... I will skip the MSC

I quickly did the servo saver yesterday before going to bed


and this afternoon, I added few things on the model



I have a doubt due to the servo. The head is supposed to be centered, but when it is centered the fixation slots on the servo collide on the left side of the bottom chassis. The manual says "cut the unnecessary part". The servo is figured out without the fixation slots... Would be great if one with a Tomcat/Bearcat/Bearcat SS confirms the setup here with pictures of the steering servo in position... Another element added to my todo list...

Remain shocks and tires to do.

I used a bit of force, as suggested by @Dadio to put the diff down to parts and being able to model it... But it did not separated as expected.



It seemed I needed to use more force again.

Flinstone mode on, with a bit of precautions, and the right tool (a mass ), I succeed to operate both the separation, and the reparation. Flinstone mode off.


And by the way what was mentioned in my previous post:

This mention is subject to doubt. I'll have to check the chassis again...

@GoMachV, if your Tomcat tires are not under blister, it would be great if you can take some measurements and pictures of the spikes : The wheels I have are quite depleted by usage, and I have no clue about the tires profile (rear). The Front one seems good, but on the other hand, I can't confirm they are original tires (it's likely, but the only way to confirm is to get pictures of new ones).

I upgraded my computer today. It was set up while I was doing my job, as a background task. The Surface Book 2 has been replaced by a Surface Laptop Studio. More Ram, and both CPU and GFX are of the newer generation.

Front Trail Masters are easy to measure, and I did them easily. For rear, i measured what was possible to measure on my set of tires, and derived from there and the pictures I found on Internet...


The new computer is definitely faster than the previous one : I did not have to wait while combining 73 bodies while it was slow with the previous one. The upgrade is validated

Next was to put thee tires on the rims... Joints are also faster.


Shocks remain to do, but I need to tear them off first...

Sorry I forgot to look!

Base of the cylinder 6mm diameter approx 1mm tall
Base of cone 4.5mm diameter approx 4mm tall

Thanks, I'm not that far of that. I'll review the cone. It seems the pictures I found were used tires rather than new. I'll replaced them by new ones

Bank Holiday today: I had a bit of time to do some CAD work.

I started by the shocks.
Everything is the same between rear and front, except the shock body, which is shorter for the rears. (I do not display the spring, as it is the side would required to be different based on the suspension movements (61 mm long, 12 revolution, section 1.25 and 15mm of internal diameter)...


Then I went back to the car model.
I first changed the tires with virtual wear by brand new ones (Thanks @GoMachV ), and I brought in the shocks.


I then put them on the chassis. Doing that, I noticed a mistake in the manual of the Bearcat SS, as it can't mount with the indicated damper bushings A at the rear. I replaced those faulty parts by a second set of damper bushings B (and that's the way the car was when I received it)...


I still need to check the steering servo position (bottom chassis to deck may require a rework for this) and review a few details...

At this stage, I don't know if I'll print parts or not for this car: almost none of the parts requires it. I'll put all parts in a cleaning solution at some point and will try a rebuild from there... And that is when I'll decide if I do print parts or not for myself.

silvertriple wrote: ↑Thu Jul 14, 2022 8:35 am I still need to check the steering servo position (bottom chassis to deck may require a rework for this) and review a few details...

I checked on the chassis and the servo I had in the car. I did not have a chance to drive it before tear it down, but I remember the front wheel were not lined up properly.

I had a look at the standard servo and the way it should be to have the head centered: in the case it is centered, it does collide (slightly) with the bottom chassis. I could gain slightly by reviewing the profile of the sides of the chassis, but it would still collide a bit, requiring at minima to file something (either the chassis or the servo holes extension)... I'll review the side profile, the top deck and will call it done .

Long pending update...

The model did not correspond perfectly to what I had in hands... I had few review of dims, more than once without finding the culprit...


In the car I had some standard servo which I'm used to have on many cars. This time I took the servo (Graupner C505) and measured it... And in fact, the servo I used as a reference is not proper. Servo length is too long (about 1.5mm) and the servo head is in real more closed about the left end by 2mm...

I'm assuming I searched for nothing and my model is correct...


Few details remain to do : making sure the walls of the gearbox are printable (I need to make sure I have always 1mm thickness everywhere), and review the diiferential case as I have a small doubt (I need to make sure it is right as it is the same for both Zerda and 44B (I don't have one yet, but I hope to find one at some point)...

Once this will be done, the files will go on Thingiverse after some prints for checks...

I don't know why I got this appearing in my items proposals on Amazon, as I did not searched for that whil looking for some cables for the printer... But it appears that pulleys are easy to find in 20T and 16T GT2, and it is the same for timing belts in GT2 in different dimension... That may be a very good reason to consider doing another diff and another Pulley in GT2 format for our Hirobos...

The gearbox halves were not printable in their original state if I refer the minimal 1MM thinkness requested by most of the printers


I reviewed the walls to get that proper.

And once done for the first half, I did it for the second one...


There is few remaining notes in my todo list :
- review the diff case : I have 1 mm doubt on the pulley position I will need to recheck
- find a solution for the top shaft bearings : initially the bearing (no ball bearings) are 5x13x5. There is no ball bearing of this size. I woulld think to do a 1MM thick printed washer (5x13x1) to complement a ball bearing

I'll do this later within this week, and once done, I'll extract all the stl files, unelss I decide to do a Powergrip GT2 version of the transmission, which means it will take slightly longer before I come to the stl extraction stage (not too much longer, that said

silvertriple wrote: ↑Wed Oct 12, 2022 4:18 pm The gearbox halves were not printable in their original state if I refer the minimal 1MM thinkness requested by most of the printers


I reviewed the walls to get that proper.

And once done for the first half, I did it for the second one...


There is few remaining notes in my todo list :
- review the diff case : I have 1 mm doubt on the pulley position I will need to recheck
- find a solution for the top shaft bearings : initially the bearing (no ball bearings) are 5x13x5. There is no ball bearing of this size. I woulld think to do a 1MM thick printed washer (5x13x1) to complement a ball bearing

I'll do this later within this week, and once done, I'll extract all the stl files, unelss I decide to do a Powergrip GT2 version of the transmission, which means it will take slightly longer before I come to the stl extraction stage (not too much longer, that said

Saw 5x13x5 bearings on eBay bearingsrus but unshielded

silvertriple wrote: ↑Wed Oct 12, 2022 4:18 pm The gearbox halves were not printable in their original state if I refer the minimal 1MM thinkness requested by most of the printers


I reviewed the walls to get that proper.

And once done for the first half, I did it for the second one...


There is few remaining notes in my todo list :
- review the diff case : I have 1 mm doubt on the pulley position I will need to recheck
- find a solution for the top shaft bearings : initially the bearing (no ball bearings) are 5x13x5. There is no ball bearing of this size. I woulld think to do a 1MM thick printed washer (5x13x1) to complement a ball bearing

I'll do this later within this week, and once done, I'll extract all the stl files, unelss I decide to do a Powergrip GT2 version of the transmission, which means it will take slightly longer before I come to the stl extraction stage (not too much longer, that said

Would the revised gearbox halves still mate up with the original ?