Dravpnir tries to build something small, again...

[Dravpnir]

For those who follow DravTech on FB have seen that there is some new mini parts in the works. Now the first prototypes has arrived of those parts, so let the building begins!

As there will be so many new parts I thought it deserved a new thread


First out is the chassis, namned SuDuZero. It is about 7" long, 2.5" wide and about 3" high. The skid do not arrive until Tuesday I am sorry to say.




The transmission will be placed so the motor sits as far in in the chassis as possible.




The Brood Mini Stubby will be able to fit fine too




A new chassis is quite nice, but it will be even better with a pair of new axles too!




The axles are based on MRCrackheads original awesome idea to offset the pumping to allow the servo to be placed beside it to get some really nice CG. Brian (89redranger) and I has been working on these axles for a while now (well tbh mostly Brian) and it is awesome to finally got them in my hands.

The axles in the pictures is only the first prototypes so there will most likely be changes made here and there. Some parts (like the servo plate) will also not be 3D printed but milled from CF on the final product. And yes, if there is interest we will try to offer these axles to the public.

The offset pumpkins will also line up beautifully with the transmissions that is mounted a bit to the side compared to the original MRC Pro chassis.

The front axles got mounts for shocks/lower link using M3 hardware. The ends on the axles in the pictures are made for AX10 chubs, but splines versions for XR10/Wraith chubs have also been drawn up.
I got 2 versions of the front axle at home. One where the pinion angle is at 7* and the servo is moved a bit more forward and one with 0* pinion angle. I need to double check that there will not be any clearance issues between the servo mount and the drive shaft using 7* pinion angle.






The rear axle got mounts for shocks/lower link using M3 hardware. The ends on the axles in the pictures are made for a single straight rear shaft, but there is a version using lockouts in the works too. The lockout version will use Axial rear shafts that you will need to cut down and grind so it fits the diff.






There is also some knuckles in the works. These are the second version of this idea, but it will need atleast one more version..






To go with the knuckles I have shrunken down the design of DravTech's Tri -Blade Cyclone CF wheels.




Another small new part is a CF motor plate for the MRC/Slickrock transmission. I need to make a slightly different version to be able to mount the Brood Mini Stubby to the original transmission.




And luckily I saved the last pair of the DravTech stainless MRC spools for this project
I haven't decided yet if I am going to drill out the stainless spool for the rear axle and solid shaft or make a new spool out of aluminum.




I will be using the HR gears in the transmission. I will also try to glue in the output shafts in the final gear to see if that can allow me to use the final gear too or if the shafts will still destroy the aluminum gear.
The drive shafts will be the nice SDI4x4 ones (4 mm to 4 mm).




And a last picture that do not show anything new, but it really capture the idea of this project I think...




And of course I need to make a template for the panels so Michelle can make some skins for it

[winnerone23]

Hot Dam that looks Way Killer in Black!!!



Drooling on myself here....

[89redranger]

Here are a few renders of the splined version of the OCP MRC housing, as well as a few of the interior volume of the center section and cover. I will get some more renders up of the rear housings with lockouts ASAP.

My intent with these was to design in as much beef as possible while also remaining as simplistic and light weight as possible.

A HUUUGE thanks should go to MRCrackhead for not only building the first, but supplying all the numbers and details to make it all work in harmony. Really, these are all a combination of a lot of parts (DravTech Wraptors for example), a lot of time, and a lot of ideas.





















And a few "teasers" of a printed c-hub design I am working on for the DravTech 0* knuckles...

[MRCrackhead]

Freaking unbelievable!

A Sudu mini chassis? Are you kidding me?

New wheel options? Sweet!

This thread just blew my mind. I knew about the axle, but the rest........wow.

That rear axle is absolutely beautiful! Nice work, indeed.

You really need to make more of those lockers so these two new axles can see their full potential. 3s, universals, and heavy duty rear shafts.....mini's may move into a whole new state of evolution.

Thanks to Brian for including me in the design process. It was fun to help out on a project that I felt would change the game in the mini axle category.

Two questions, though.

Do you think 2 screws will be enough to keep hold of a 7950 type servo?

My axle has 4 screws holding the servo in place, and I felt that was needed with the servo hanging off the back of the axle so far. It seems to have a lot of leverage against the mount.

Also, would you consider 2mm shock mount holes?

You may be the only one on earth with those ultra cool shortened SCX10 shocks.

The rest of us are running Losi Pro shocks, and they are 2mm at the bottom.

Seems it would be very easy to drill a 2mm hole to 3mm if you wanted to; but not so easy to go the other way....

[Dravpnir]

Thanks Brian for sharing those photos

Originally Posted by MRCrackhead

Freaking unbelievable!

A Sudu mini chassis? Are you kidding me?

New wheel options? Sweet!

Nope, no kidding around here

So far I am very pleased with how the chassis turned out. The skid will need a revision though I realized yesterday. Angled mounts for the rod ends in the skid would be to some great advantage with the short wheel base of the mini.

I will do my best to get this crawler RTR for the Nordics in the beginning of June to really try it out.

Originally Posted by MRCrackhead

This thread just blew my mind. I knew about the axle, but the rest........wow.

That rear axle is absolutely beautiful! Nice work, indeed.

Coming for you, that means a lot, thanks

Originally Posted by MRCrackhead

You really need to make more of those lockers so these two new axles can see their full potential. 3s, universals, and heavy duty rear shafts.....mini's may move into a whole new state of evolution.

I have made a small modification on the locker and made a spool for the rear axle for a straight single shaft. I will see what they will cost to make, but last ones wasn't cheap. So I hope I can make more, but I will not promise anything.

Originally Posted by MRCrackhead

Thanks to Brian for including me in the design process. It was fun to help out on a project that I felt would change the game in the mini axle category.

Two questions, though.

Do you think 2 screws will be enough to keep hold of a 7950 type servo?

My axle has 4 screws holding the servo in place, and I felt that was needed with the servo hanging off the back of the axle so far. It seems to have a lot of leverage against the mount.

Also, would you consider 2mm shock mount holes?

You may be the only one on earth with those ultra cool shortened SCX10 shocks.

The rest of us are running Losi Pro shocks, and they are 2mm at the bottom.

Seems it would be very easy to drill a 2mm hole to 3mm if you wanted to; but not so easy to go the other way....

Actually in the version in my pictures there is 4 screws securing the servo mount to the axle. The two front servo screws goes through the plate and into 2 mounting posts in the axle.

Regarding the shock hole diameter, I either have to start selling the mini SCX10 shocks, or just do like you mentioned. The later seems to be a better solution. Thanks for pointing it out. It is easy to get "home blind".

[MRCrackhead]

Originally Posted by Dravpnir

Actually in the version in my pictures there is 4 screws securing the servo mount to the axle. The two front servo screws goes through the plate and into 2 mounting posts in the axle.

Sorry, it was very late and I simply didn't look close enough.

The bottom picture clearly shows the mounting posts below the servo screws.

Very clean, nice work.

Also, I forgot to say how awesome those knuckles are in my last post.

There was just so much awesome in your first post, I was overwhelmed......haha

Lots of really cool ideas at work in those knuckles. Again, nice work.

[chris.martell]

I also had a concern on the shock mounting holes being 3mms and thought last night that it would be awesome if you could produce a shock end that had a 3mms pivot ball but threaded onto a mrc pro shock. Possibly a cheaper route than those sick scx shocks you have.

[chris.martell]

I'm super excited between this thread and Merc's Mini Super thread my interest in crawlers is starting hook me again.

[89redranger]

These are what I use on my Wraptors to fit the bottom end of my mini shocks, and they work pretty slick actually. The same parts you guys all use to mount the upper ends of your shocks anyway. I know some worry about the shocks popping off, but I've only had it happen a few times, and as I've said, if the shock didn't pop off in that instance it probably would have broken or bent the shock anyway. I'm sure Tobias and I will have a few more chats about these before all is said and done anyway, and the shock hardware holes may change, but this is an option. It's actually a very light and simple solution that is probably still stronger than the little tiny M2 hardware...

Losi: Ball Stud, Long & Shock Mounting Brace: MRC: Losi (LOSB1444)

[Dravpnir]

Originally Posted by MRCrackhead

Sorry, it was very late and I simply didn't look close enough.

The bottom picture clearly shows the mounting posts below the servo screws.

Very clean, nice work.

Also, I forgot to say how awesome those knuckles are in my last post.

There was just so much awesome in your first post, I was overwhelmed......haha

Lots of really cool ideas at work in those knuckles. Again, nice work.

Well it is not that clear if you ask me

But people should not be afraid/shy to ask questions if you see something that you think looks strange or bad. It is too easy to overlook something...

Most of the knuckle idea comes from Dlux's 2.2 knuckles, so I cannot take much credit for those, but yeah they sure are nice
Like I mentioned when I showed pictures on the first version of the knuckles. If I am going to offer the knuckles to the public it will be under "license" from Dlux as I feel they are to much of a copy from his 2.2 knuckles.

Originally Posted by chris.martell

I also had a concern on the shock mounting holes being 3mms and thought last night that it would be awesome if you could produce a shock end that had a 3mms pivot ball but threaded onto a mrc pro shock. Possibly a cheaper route than those sick scx shocks you have.

The shortened SCX10 shocks is quite easy to do with only hand tools, but I will look into offering them. The hardest part is to find cheap SCX10 shocks for me that is living on the other side of the pond...

Originally Posted by 89redranger

These are what I use on my Wraptors to fit the bottom end of my mini shocks, and they work pretty slick actually. The same parts you guys all use to mount the upper ends of your shocks anyway. I know some worry about the shocks popping off, but I've only had it happen a few times, and as I've said, if the shock didn't pop off in that instance it probably would have broken or bent the shock anyway. I'm sure Tobias and I will have a few more chats about these before all is said and done anyway, and the shock hardware holes may change, but this is an option. It's actually a very light and simple solution that is probably still stronger than the little tiny M2 hardware...

Losi: Ball Stud, Long & Shock Mounting Brace: MRC: Losi (LOSB1444)

That is a nice idea Brian, but yes one more thing to consider for the final version

Originally Posted by chris.martell

I'm super excited between this thread and Merc's Mini Super thread my interest in crawlers is starting hook me again.

That is the best result ever with this thread. There cannot be to many mini's out there


I feel it is time for me to dig though my boxes here at home to dig out some parts to sell. There will be much needed $ to bring all of these ideas into reality and I am not patient enough so I want it to happen sooner than later

[MRCrackhead]

Originally Posted by Dravpnir

Well it is not that clear if you ask me
The shortened SCX10 shocks is quite easy to do with only hand tools

You'll have to explain that further. I purchased a 3mm die and attempted to extend the threads on shock shaft.

Thought if I could extend the threads, then cut some off, I wouldn't have to mess with the c-clips end of the shaft.

It did not work.

I limited the shocks instead.

[89redranger]

^I too ran into this, and instead plan to drop my billet Icons off with a machinist to have the shafts and bodies shortened. Tobias, please do elaborate when you have time. As you know, I've had my go-rounds with these shocks a few times now, and they still continue to sit because of trouble re-threading the shaft. Shortening the bodies shouldn't be a big issue, but I may as well have them machined for a few extra buck at the same time as the shafts. For a while EY was selling Ti shafts in custom lengths for SCX shocks, but I believe they were designed around the Eggressor threaded delrin bodies and Traxxas seals, which is an even larger investment yet...

[Dravpnir]

I only fastned the shock shafts in a vise (think I used aluminum jaws to keep the shaft in place without damageing it) and extended the threads. While the thread die still was on the shaft I cut off the shaft and then back out the die to clear up the threads that got damaged in the cutting. I used a normal cheap HSS M3 die. I might have used some WD40 as cutting oil, I cannot remember.

I had much more trouble to make sure I cut the the body straigth. As I use bladders in my SCX10 mini shocks you need to cut the body pretty straigth to avoid that the shock will leak.


Most of the axles parts has now be altered a bit and new prototypes has been ordered. This time I also added some weight holders to the rear axle. Hopefully I wil get everything home and manage to assemble the axles so I can run this mini during the Nordics. CF parts has also been ordered so I can put together some proper axles.

[MRCrackhead]

Perhaps another attempt is warranted.

I had the shock shaft in a drill chuck.

This particular drill will try to break your wrist before it lets a stuck drill bit spin in the chuck.

I kinda figured if that wouldn't hold it, nothing would.

Thanks for the info.


Love the idea of rear weight holders, by the way.

That rear axle just keeps getting better.

[Dravpnir]

Originally Posted by MRCrackhead

Perhaps another attempt is warranted.

I had the shock shaft in a drill chuck.

This particular drill will try to break your wrist before it lets a stuck drill bit spin in the chuck.

I kinda figured if that wouldn't hold it, nothing would.

Thanks for the info.


Love the idea of rear weight holders, by the way.

That rear axle just keeps getting better.

No problem and thank you

Realized that I have forgotten to post some pictures of the skid that arrived tuesdays.

It fits and works as I had hoped


The CF edges are fully protected.




The motor sits quite far into the chassis and the outputs from the transmission almost lines up perfectly with the outputs from the axles.

[89redranger]

Gonna look sexy with all blue printed parts! I can't wait.

Game changer? None of us but MRCrackhead and RICrawler really know yet...

Positive evolution for a once dying class? Absolutely!

[OTHGbronco82]

Is the chassis going to work with regular MRC axles too? Either way I want one.

[Dravpnir]

Originally Posted by 89redranger

Gonna look sexy with all blue printed parts! I can't wait.

Game changer? None of us but MRCrackhead and RICrawler really know yet...

Positive evolution for a once dying class? Absolutely!

If this leads to that some people get inspired to dust off their mini's and get them back on the rocks again, I think that alone is some excellent result

Originally Posted by OTHGbronco82

Is the chassis going to work with regular MRC axles too? Either way I want one.

Yes, of course it will work with normal MRC axles too. After Nordics I will put it together with my old MRC axles and take some pictures.

[Krawler Konceptz]

Skins designed

[89redranger]

Originally Posted by Krawler Konceptz

Skins designed

Skins look awesome!

Does this mean there will be clear panel sets available as well?