Margouillat AR60

[TotoRax]

Hi,

Like always, fantastic work!
Why the change from the Stuby to the Puller?
Weight?

Puller or Stubby have almost the same weight.
I am very satisfied with the stubby, but I sent back him for reconstruction (it had almost 2 years). Like that is going to set 2 months (very long post delay)... he needs that I run meanwhile.

I also tried some different springs,for me it's most important to get the best sidehilling performance.But i'm not sure what works best

Yes, for me too. But a shafty does not adjust as a pro.
The dig allows to correct (to mask) certain problem, not on a shafty, particularly in crossing of axles. it is thus necessary to watch to master well everything aspect of the comprotement of the crawler.

 

[TotoRax]

Hi,

I try a modification which trots me in the head since a certain time, and that will be the occasion to test the print with aluminum and steel.
The idea is to improve the existing Cardan joints. They function correctly in spite of the extreme steering angle that I imply to them. But without surprise, that causes jolts not always pleasant and which can in certain cases harm piloting.
Egressor had already to work on this kind of project, but I have neither equipment, nor his talent of machining, I will thus be satisfied with simple parts printed to start.


The principle is to create a part to be intercalated between the two parts of the Axial Cardan joint.


Then it is enough all to go up (one needs 2 sets of Cardan joints to do one of them, because the small parts should be recovered)




That implies a new C-Hub and knucke.


Thus it has needed to create these new parts and as long as to make bring some modifications, as the integrated steering supports.




With its Cardan joints, it nor will have more jolts and operation will be much more smooth, because each Cardan joint will take with the max only 30 or 40°.

C-Hub will be printed out of aluminum, while knucke and the connector of Cardan joint will be printed in steel. One should not expect printed parts of the very high mechanical characteristics, and the connector of Cardan joint should not support the efforts of operation a long time. Here, it is just a prototype, to validate the whole of the elements, and to make some travelling tests.
I think that the printed aluminum c-hub should hold in time. The knucke could be also out of aluminum with some correction of design.

With final, with a hub of wheel of 5 or 6 mm, I should preserve the current track width.

The parts are already in print, I need as usual watching for the post-men :twisted:

@+

 

[Del Monte]

Very cool idea! Are you planning on using an axial inner shaft?

I bet those parts aren't cheap to print in metal :shock:

 

[xkill]

Like always, fantastic job!

 

[TotoRax]

Thanks Del Monte.

Yes, I planed to use the axial inner shaft.

Steel print price is correct, but expensive in aluminum. I I have test in Titane, but 250€ for each parts :shock:

 

[TSK]

Ei recall Egressor doing something similar but he used CVD style ball stubs instead of the universal type joint. Very cool

 

[Del Monte]

Thanks Del Monte.

Yes, I planed to use the axial inner shaft.

Steel print price is correct, but expensive in aluminum. I I have test in Titane, but 250€ for each parts :shock:

:shock:

Although, if you we're to pay a shop to machine just 1, it would probably cost more.

 

[TotoRax]

Like always, fantastic job!

Thanks

Ei recall Egressor doing something similar but he used CVD style ball stubs instead of the universal type joint. Very cool

Yes, I have just read again his post and it is impressing the number and the quality of the modifications which it made!!

 

[TotoRax]

:shock:

Although, if you we're to pay a shop to machine just 1, it would probably cost more.

Yes.

I like the 3D print because that allows quickly and at a cost reasonable to make very succeeded prototypes "thumbsup"

 

[TotoRax]

hi,

A short teaser :mrgreen:



To follow...

@+

 

[xkill]

How does that aluminum part feel?
Strong or bit "soft"?

Great job, like always!"thumbsup"

 

[TotoRax]

Hi,

As you were able to see it, parts arrived :mrgreen: The printing of the metal parts is apparently much longer than that plastic...

The aluminum and stainless rooms are of very good quality, very solid, And one nice finish, I am the surprised first one. I think that the connector of universal joint could hold a few hours of functioning. But the precision is not there... I have of big gap from measure in particular at the level of the bearing housing :evil:

Thus a pic of the printed parts. The steel parts look like a little the fantasy jewel :roll:




To fix C-hub, it is necessary to cut the end of the axle at the level of grooves.



Having played a moment the dremel, in particular to take back the bearing housing, the final set up.




And now, it is the moment to study the problems which puts this type of assembly. On the paper it is great and simple , but there are 2 major problems.
The first one it is that a part of the universal joint have to can slide when we increase the angle of the universal joint. Then, according to where we place the point of pivot that the direction, 2 parts of the universal joint do not take, as we could believe it, the same angle. This second problem is generated by the first problem which tends to move the universal joint.

On this assembly, the point of pivot is quite logically placed in the middle of the universal joint. It is like that that I made it make.
At the level of the modelling, I had already identified that the main tree should slide of more than 3 mm, then than for streering of 80 ° (the absolute limit that I settled) the external universal joint took more angle which that interns.



To harmonize the angle of universal joints, I have to move towards inside of 2mm the point of pivot of the steering. And there, angle are almost equal. But it is to be studied closer...


Here is where I am there, today.

@+

 

[Cirederf]

A VERY VERY VERY BIG CONGRATS to you mate !!!! Wolrd Champ in 2.2S !!!!!wow You rule it and worth it !!! BIG UP to you Steph ! i hope my visit get you mood back in ....;-)

 

[xkill]

Congrats Stephan!!
Having watch you drive that car almost one year ago I can only imagine how it was today!
Again, congrats for the Top Spot! "thumbsup"

 

[clod booster]

Congrats world champ and a very interesting read! Cant wait to see when you make some more progress.

 

[JatoTheRipper]

This is incredible! Nice work.

 

[maduff]

Bravo encore.............quelle démonstration!
Ah oui et merci pour le test drive...

 

[Del Monte]

Amazing drive at World's! Congratulations!!

Also, thank you for letting me drive your creation on Friday. I have never driven a 2.2s rig before that could keep up with my 2.2m :shock:

 

[TotoRax]

HI,

Thank you guys for your comments "thumbsup":mrgreen:

... i hope my visit get you mood back in ....

Thanks Fred "thumbsup" Which regret not to have seen you on rocks

Amazing drive at World's! Congratulations!!

Also, thank you for letting me drive your creation on Friday. I have never driven a 2.2s rig before that could keep up with my 2.2m :shock:

Thanks Jake, it was a privilege to meet you. I was not able to see you drive during the competition... I just saw your finale in 2.2m and it is impressive to see your piloting. Everything seems so simple, it is fluid, without stress. It is a very beautiful 1st place. Samu as extremely good during the races, but in less successful during finale... Congratulations also to Laalaa for his very nice 2nd place.


Otherwise, I am more than satisfies results.
In 2.2M, I manage to finish all the races with my shafty, with a final classification in the 29eme place and a widely negative score (-53). The races 2.2M were very well drawn, of beautiful difficulties and especially all the races were finisable.
In 2.2S, he has really needed to fight to hope for a podium with so many good current pilots. It was necessary to finish all the races and to make all the doors bonus. The gods of to rock were with me and I was able to make quite bonuses except one, but I was a little bit ambitious on his approach, that would have been able to pay. There also the races were very well drawn and I took a great pleasure to make them.

Margouillat great well worke, no problem on all the races (6 in pro and 6 shafty) and on a however testing spot La Couronne, it is a good indicator of reliability. The 3D parts perfectly held shocks.

Another big big bravo to Samu Team for this comp., in spite of my doubts to hold a schedule so tight, congratulations "thumbsup""thumbsup" And I repeat but also one thank you for Cougar Team for the part stewardship of this comp. You mighty worked well.

I has to forget too many things ... saddened ... but it will remain an exceptional experience!!

 

[ZZR 1100 Racer]

BIG congrats worldchampion in YOUR class! How somebody said "...now it's official...", but me and some more knew since some years the name "mr. shafty" came not from nowhere! Enjoy the rumor my friend!!!