Kraton EXB Prowler edition

[Prowler666]

The beginning of my RC journey stared about 40 years ago with a Tamiya Sand scorcher, Last year decided to buy my eldest an RC for xmas so bought him a Hobao hyper ST (Nitro) not realizing batteries and motors had improved so much over the years, after a big learning curve of jumping into nitro and the normal problems/annoyance and general noise of them I converted it to brushless.. then got the bug haha.
I did some research and watched a shed load of vids and made my mind up to get...an EXB
Then ofc started on the tweeks and upgrades
First thing done was removing standard decals and replacing with custom ones. Screw down body mainly because it's easier to attach imo, Spring loaded wheelie bar installed for obvious reasons
Wheelie Bar:- https://www.aliexpress.com/item/100...earchweb0_0,searchweb201602_,searchweb201603_

Pretty standard electrics at the point of taking these pics HW Max6 1650kv combo with 20t pinion, Radio link RC4GS v2 with telemetry and the R7FG receiver including gyro (so should be good for 600m range)
Transmitter:- https://www.aliexpress.com/item/32809441148.html?spm=2114.13010708.0.0.3a994c4doEOQ8j
Receiver:- https://www.aliexpress.com/item/330...earchweb0_0,searchweb201602_,searchweb201603_
Servo:- SPT5828W-180 28kg 8.4v 0.06s Waterproof High Speed/Voltage
https://www.aliexpress.com/item/1005001877175960.html?spm=a2g0s.9042311.0.0.27424c4dpD6W6o

Once all this was installed and about ready to run it kind of seemed too heavy for the spring rating, so located some big upgraded springs which are more than twice the lb/mm rating of stock. Supplied by Flexo springs
Rear https://www.flexosprings.com/search-products?sku=343732
Front https://www.flexosprings.com/search-products?sku=343728

Following more research into heatsinks/fans found that most need modding to fit or that due to the fins on the can heatsinks might not be the best idea so it got my mind to thinking of an alternative way to mount a fan far enough away from the motor as to not be affected by the motors emf and to not put excess weight directly onto it, so designed the following two brackets to test (going to try the single to start with to see if it's enough)

Fans are from ali express, which are really nice for the price
https://www.aliexpress.com/item/4000726684212.html?spm=a2g0s.9042311.0.0.27424c4dB26kIJ

 

[#ARRMArcfanboy4life]

that is a very nice rig

 

[Prowler666]

Next up is my own design and making of ESC fan mount bracket, drawn on Solidworks then printed out at 1:1, glued onto some 5mm thick aluminium then drilled filed and sanded.
Just a few boring pics of my process to make the fan mount, but maybe might inspire someone to do something similar as its not that hard to do with a few basic tools Once fitted I don't really think anyone could tell

And finally the finished item..

Reinforced the shell with Hitack drywall tape and clear silicone sealant, which keeps it nice and flexible and is really cheap compared to shoegooing it

I looking at the Proline mx38 tyres but seem to be out of stock in most places at the moment, but will be investing as soon as i can get some

 

[#ARRMArcfanboy4life]

those tires put a lot of stress on the drivetrain and steering servo try a smaller tire (this is not from personal experience but from the incredible people on the forum telling me so)

 

[Prowler666]

those tires put a lot of stress on the drivetrain and steering servo try a smaller tire (this is not from personal experience but from the incredible people on the forum telling me so)

I do have a set atm but they are on my sons Hyper ST, that atleast seems to run them with no problems so far, so i will probably throw them on mine for a few packs to see how they feel before jumping in to purchase tbh.

 

[Prowler666]

Finally got the fans fitted and tested now, I decided to go with the single motor fan to begin with to see if it enough on its own. Motor fan linked to the receiver via separate switch, so I can turn it off and on as required. still need to find a better place for the switch to mount rather than the brace arm.

 

[Prowler666]

Fan covers arrived and installed today stainless steel mesh with aluminium outer
Covers supplied by Farnell
https://uk.farnell.com/sepa/fm40/emc-fan-screen-grid-40mm-ss/dp/2493520?st=40mm fan cover

 

[Prowler666]

A few updates installed over the weekend

Centre diff hybrid build to test (front end with max LSD rear end open) 60k oil

Vitavon front and rear hubs

RPM front arms
HR rear gearbox housing
HR Bellcrank
M2C shock pistons (Hybrid)

Drop test of the above with My heavy springs on and hybrid M2C pistons

M2C rear shock tower
M2C Rear shock tower brace

GPM front and rear centre brace mounts

 

[Prowler666]

Received some even heavier springs to install on the rear, much testing to come lol.

 

[jschlosser0405]

What is the material you used for the pistons?

 

[Prowler666]

What is the material you used for the pistons?

In the pics it was a thin plastic sleeve that i had some tools or something in, different thicknesses will give different results so need a little experimenting.

 

[jschlosser0405]

Ok sounds good. Thanks

 

[YoEddy]

Keep up the good work ... have also used many of the same M2C /Vitavon/HR ... parts on my EXB project, and I'm curious about your further experiences, especially regarding the modified springs, because with a current total weight of approx. 17lb, that's definitely an important issue...!

 

[Prowler666]

Will do, I haven't had much time lately to wrench and bash but will hopefully get back on track soon.

 

[blackops]

@Prowler666 nice looking rig man, turning out pretty sweet and giving me more ideas for my Kraton 6S EXB build.
How did you end up doing the screw down attachments for the body posts? That looks interesting and has me thinking.

 

[Prowler666]

@Prowler666 nice looking rig man, turning out pretty sweet and giving me more ideas for my Kraton 6S EXB build.
How did you end up doing the screw down attachments for the body posts? That looks interesting and has me thinking.

Thanks, the posts I just ordered some 4mm x 20mm grub screws, then some thumb screws from Ali express. Cut them off just above the point that the body touches with a small hacksaw so they will screw it down tight.

 

[YoEddy]

Hello follow your construction closely and are currently also before the decision of new springs ... because my EXB has virtually Full-M2C installed and is therefore significantly heavier, as series ...!

How is your Kraton the current status regarding the springs?

Would like to have springs that are significantly better cope with the weight but still do NOT neglect the soft component ..., because too hard is then more of a disadvantage as too soft springs !

Have me on the basis of the tests of "East Tactics" for the combination of 5000 damper oil, M2C EXB piston plates and the 10548 Century Spring's decided what me at springs unfortunately much ..is too stiff, so my question to you, how current your experience are with the FlexoSprings
Front 343728 and 343732 Rear, because your drop test on Youtube with these springs look very promising !?!


Best regards !

Translated with www.DeepL.com/Translator (free version)

 

[dure16]

Can you tell me about those shock/spring covers?

 

[YoEddy]

Can you tell me about those shock/spring covers?

Do not understand exactly what is meant by the question, sorry!

 

[dure16]

Do not understand exactly what is meant by the question, sorry!

It looks like @Prowler666 has covers over the springs. I'm looking for a link to buy them.