View Full Version : MiX Universal 1:28 AWD chassis, progress continues... and continues...

2008.05.31, 08:48 PM
I intend to update my TinyRC blog (http://www.tinyrc.com/forums/blog.php?b=53) with more progress on my MiX chassis... I recently solved most of the problems I was having with the concept, so I am hopeing to have an operational prototype soon... I am currently sourcing parts for the prototype...

For now, my first blog post on the MiX is about the past concepts I have tried... some of the renders of the versions before I was really serious about this thing are quite funny looking. :)

There are better 3D Renders then I have shown in the past of more recent versions as well...

So.. is anyone still interested in this? am I wasting my time? I will be making at least 1 for myself... if it works I will be selling kits, and they will NOT be cheap.

2008.06.01, 02:19 PM
I'd be interested in one if it was indi-suspension and was able to be turned into a buggy easy with different suspension arms, driveshafts, links, and a body. If you need some to test one out you can e-mail me at Mattdg67@hotmail.com

2008.06.02, 03:13 AM
It was and still is a very cool concept. My only concern is that with 1) the number of parts to build a single car and 2) the number of parts to support its numerous configurations, the cost is going to be way too high for you to make even a few cars. And belt drive... materials selection is going to be crucial for the belt, the standard timing belts intended for small machines and 1/10 TC's just aren't going to wrap around tiny pulleys. Either that or you could go the TGR way with a non-tooth belt (you could even use a 3mm wide rubber band) but then the drivetrain wouldn't be very free.

Suspension-wise, I love the concept but I fear that in 1/28, unwanted friction will hurt its effectiveness. If I had full reign over the design I might even try out a deDion tube suspension for its almost frictionless action (and then use a tunable damper in conjunction with it).

Your car though, I just wanna see something cool come out of your 7-year project. ;)

2008.06.02, 08:53 AM
It looks like your main goal is to get this chassis to fit most all the bodies availalbe out there. Id have to see some better renders to get an idea of how it will handle compared to the current MA010. If it will allow me to run a bunch of different bodies, but its not cometetive on the track, then I wont be interested. Heck, I dont think think it will be a big seller if it turns into a high priced MiniX.

I have been interested in this for a long time though, so Im very curious as to what direction it will head :D

2008.06.02, 10:35 AM
In the end my chassis will be cheaper then a fully configurable Mini-Z, not to say some one is going to buy every setting of every part... but if you were to buy all the alloy tie rods, knuckles, motor pods etc... needed for every length width degree and setting... it would actually be cheaper to buy my chassis... I am hopeing to charge in the $250 to $500 range, depending on the warranty included with it, if say it turns out to be a really good and strong design I may charge close to $500 for a kit that will include a lifetime warranty (on most of the parts) you send in a part broken for any reason, and you will get a replacement of that part, installation and shipping would not be included. So even if you have a chassis with old parts, if those old nylon parts break you will get an updated metal version if you send in the parts...

Most of my parts will be metal, some alum, some brass, and some NEED TO be titanium or a strong steel... there will only be about 6 or 7 plastic parts... the battery bay has to be or it might short (even carbon can short a battery), but there will be a few other nylon/abs parts, the first prototype will be mostly machined nylon... what survives as nylon might stay nylon in the first few versions.

One draw back of my chassis is it might wind up being heavier, at least the prototype will be because I might be able to widdle down wall thicknesses and put holes in some of the parts to save weight.

The goal of my chassis is to not have to swap out any parts when changing the race settings, I hate having to take the car apart and swap a tie rod just for 1 degree, test it, not like it then have to swap it back... in my car you pull the car up to you, pick it up, losen a screw move a part tighten the screw back up and slap it back on the track... just like most larger RC cars.
This is true for length, width, toe, camber, caster, and ackerman.

Right now if you want to change from a 86mm Porsche body to the 102mm LM bodies... you do not have to buy or have any spare parts in your tool box. You just swap, or MiX ;) the parts around on the chassis and your good to go.. you will not even have to swap the rims or even the belt!!!! I got the belt setup so it works from 86mm to 102mm... This was just a fluke of the current design it kind of freaked me out when I saw it was possible, it actually wound up using less parts than an adjustable length shaft!!!

However to go longer (truck/monster) you will need to go to the 2nd sized belt. So, you will have to replace parts to change from racer to truck, or you will have to buy the expansion kit to change to the AWS, MonsterMiX, BuggyMiX, or 1:18MiX mode (Longer A arms, Half Shafts, and possibly shocks).

The motor looks high in the renders (Render is 90mm long, narrow-est width), but the top of the motor only just crests over say the bottom of the windows on a F40 body... and that is pretty low, it will still fit the LM porsche bodies and I think it may even fit under the shelby cobra body and that is a convertible with no top... so I believe the MiX is low enough, and adjustable enough that it can be adjusted to handle the way the driver wants. I strongly beleive it has potential to race better... but obviously it has not been track tested so it could totally flop, which is why I have not accepted any $ for pre orders yet, and why I am currently sourcing parts for the first true prototype, im sick of only having a 3D-prototype.

2008.06.05, 04:23 PM
... More that I didnt answer.

The belt is toothless, it was problems with a toothed belt that caused me to abandon it in the beggining... I was developing a way for the front to differentiate from the rear and it always resulted in making parts that could slip... well a toothless belt can just slip over if it needs... or it can act like a clutch/traction control... It will basically be a large O-ring for the most part. The pulleys are similar to size/shape of some of the lego pulleys, and would use a similar sized belt system. I cannot use a rubber band the stretchyness of it would bind the pulleys... and it would not work right.

The DeDion suspension I do not like, it apears that it would just compound any body roll ... but I do not know much about it.

I do expect a friction issue with the suspension ball studs, but I do not expect it to be a problem the way I have it... at least it will not be as much friction as the current Mini-Z knuckles sliding up and down a shaft.

2008.06.06, 02:45 PM
Wow... Long time no see.
Its cool your still working on the MiX. :D
Remember... Count me in for 1 full option kit. ;)
If you need any help with parts sourcing drop me an E-Mail... Me and my Dad may be able to help. (iPhoneJames@gmail.com)

2008.06.15, 12:20 PM
Still working on it...

Since I do not yet have my own rapid-prototype machine, I have been fishing for quotes for my few plastic parts on the car... these are the only complex parts I have... the battery bay/door and differential housing etc...

These parts and a set of temporary parts like test rims, and A-arms etc... will cost me $1200 on one car, and that is not even 1/4 of the parts... :) I am wondering if it would be possible/cheaper to have the parts milled... not sure the part can be its kind of weird shaped.

Strangly all the other parts in the current concept apear to be rather simple and easy to make... I may even be able to make half of them on the wire EDM machine, lathe, laser cutter, water jet etc... in the school machine shop. I would rather just pay some one else to make the parts though rather then fight the learning curve on the machines, especially if I am going to make more than 2 or 3 of these things.

So.. all that is holding me back right now I guess is money... and maybe finding places that I know/trust/can afford to make the parts in mass quantity later.

Would anyone mind having to cut the corners off of the Nose Mount for their bodies to use them on the mix? It may effect weather the nose mount still works on the Kyosho Chassis... since it thinns the area around the screw... (I use the other 2 holes to mount to the MiX). I had to do this to make 1mm more of space where I moved the shocks... I asked a similar question in an old thread before but it was about shaving the center area to clear the diff house, the belt drive fit with out having to do so in this version.

2008.06.15, 02:41 PM
Hate the learning curve.

Iíve been thinking about trying something like this, using epoxy molds for prototype parts:
But it would be so much cheaper and if someone else would try it first:D

2008.06.16, 06:54 AM
Drac, IMO you should try your best to avoid having to modify stock parts, especially a modification that will weaken it, like cutting the front clip. You could reduce the steering angle; the "outside front" wheel (turning towards the front) only has to go about 25 degrees to get enough steering for 99% of situations, so you might consider pushing the shocks out 0.5-0.75mm to take advantage of the space freed up after doing so.

LBRC- Dude... home injection molding... :eek::cool::D I certainly want one of those too, it would be so handy! Don't have to worry about the repeatability of machining 40 Delrin bulkheads, I can just get one perfect one and copy it over and over again with molten Delrin scrap... :)

2008.06.16, 11:10 AM
The part of the front clip that I cut off is the part that usually breaks off anyway ;). I already played with all the space I had up front... It is possible I will use a spring-only shock, if my nano-oil filled design fails... in that case it will be smaller DIA and it will fit with out cutting the corner off.

This is more than would need to be cut off... would only need to cut off half as muc or even less... I may also put another screw hole in so the lower end of the shock can move over, but this would only be useable in "wide" stance when the knuckle is moved outward.

2008.06.16, 11:46 AM
I wouldnt cut my body clips to mount to your chassis. I do too much switching from body to body and chassis to chassis. I wouldnt want to deem any body (or clip) un-usable. Besides, I wouldnt want to weaken up "the part that usually breaks off anyway".

2008.06.16, 12:39 PM
I double checked it and the way it is right now... if you only use RACER/AWD bodies, and the RACER/AWD ride hight/stance... you will not have to cut the nose mount at all, but it comes really close to touching, so it may need to be sanded or shaved depending on the thickness of certain body's nose mounts... however when the car leaves the ground the shock spring will force itself down to the nose mount limiting the rebound. This is the only reason to cut it on a racer. As long as the car never leaves the track by jumping or rolling this really wont be a factor. The MR02 has 0 negative shock travel so nothing is really lost. I however want this to be a sort of RALLY chassis... so making the space for extra shock travel was important.

If however you want to raise the body to overland or monster stance and still use a body that uses the nose mounts, you will need to cut the corner off, so the spring area can clear... this is why I think just adding another hole will solve the problem you can just use the 2ndary hole in monster mode and not have to shave/cut the nose mount...

Also Kyosho sells the nose mounts to most of the bodies seperate. If anyone swaps chassis back and forth a lot, they should have more than one anyway... They should just sell 2 with the body... and do away with the extra packaging and part tracking/shipping... might save money in the long run.

This is the clearance with out it being cut or shaved, with a slightly exagerated worse case scenerio nose mount...


2008.06.16, 03:20 PM
Relocate the lower mounting point of the damper 0.5mm outwards and you'll be fine. ;)

Btw you've got some tiny hardware in that design of yours... looks like Micro-T caliber hardware with a hex head to boot, lol. If it's possible please try to use a size around 2mm dia. as anything smaller is a pain to work with. That's just my $.02 from a consumer standpoint.

2008.06.16, 03:48 PM
I cannot really move the shock out .5mm and it is still not quite enough to completely clear the nose plate... I still do not think rounding off or chamfering the corner will harm the Nose plate that much...

A lot of the stuff does go below 2mm dia. Typically 1.5mm... however the ones that do, it is usually just an area of the part that does... reason I will need hardened parts and not cheap zinc parts. There are a few REALLY small parts, for example parts similar to the U joints on the Kyosho AWD... these are not intended to ever be taken apart again once assembled... hopefully they will just come assembled... but they can be.

If the design works.. I expect a lot of people to be ordering just my differentials and shocks for their own projects... micro T, AWD Dnano lol... etc...

2008.06.16, 06:26 PM
I cannot really move the shock out .5mm and it is still not quite enough to completely clear the nose plate... I still do not think rounding off or chamfering the corner will harm the Nose plate that much...
Believe me, it does. Those plastic clips break pretty easily in a crash, so if you have your customers even modify the clips a little bit you're essentially asking them to buy whole new body clips for every body they run, for one chassis. On this point I do sympathize with hrd.

If you can't move the dampers then maybe you should just stick to an Xmod-style shock. If you design some grease grooves you can still have damping, of course the trouble is that the front and rear springs would be different sizes. :confused:

2008.06.16, 09:19 PM
As I said it does not have to be cut nearly as much as I did in the render above... just sanded off...

2009.03.15, 04:06 AM
As usual every march I get in the mood to update my plans for the MiX Chassis.

I decided to sacrifice compatibility with a few bodies... and put the shocks back on top of the chassis. This should be better then shaving the nose plate, and there was other complications with putting the shocks there anyway.

It is likely there is enough room for most of the bodies this way, I was intentionally over estimating how low the hoods where... the LM porcshe might be the biggest problem.

This would not have been possible if I didnt have the "duh factor" when realizing I could save space by having the shocks share the top screw. :)

Here is a new shaded drawing, showing the MiX Racer and the MiX Truck - NO parts are swapped to make the two, other then tires. Just a few adjustments of length, width, and height...


2009.03.16, 05:23 PM
Added the Monster Mode... This will require a longer piece kit, axles, a arms, belt, etc...

2009.03.16, 06:24 PM
Looks very cool Drac! Maybe you'll finish it one of these years... :)


2009.03.16, 07:06 PM
The design is finished...
I just need to machine a prototype to test the 2 or 3 things I am worried about in the design.
And before I do the prototype I need money, I cannot even afford to eat let alone build a $1500+ prototype lol...

I am very eager to build myself a prototype, so I at least have a REAL mix, a real copy of all my work...

But I am not in a hurry to mass produce these, since there really isnt any legal race to run them in... maybe 50 of them at some point.

2009.03.23, 04:41 PM
all i can say is wow:eek:you definatly put some effort into you car. i wish i had that kind of money to put into a car. If you need a tested just let me know as i would love to see what this car could do.

2009.10.19, 03:09 PM
nice design... but personally, I would go for the gear/shaft driven (if 4WD) rather than the belt... because finding a commercially available belt would be harder.

BTW for a cheap option for prototyping... have you come across this group

maybe you wouldn't need $1500 to make a prototype.

2009.10.19, 03:45 PM
I am heavily into those RP machines... but if I was to build a prototype on a rep rap... It would have to be 3 or 4 times the final size... due to the low tollerances on the prototype machines. Even the $1,000,000 machines are still not quite accurate enough to do small parts.

My dream machine is the Arcam... it makes Titanium Parts!! I REALLY want one, I could just design RC car parts hit print and mail them off :)... well almost, they would require a bit of post processing.

And I replied to your PM.

2009.10.19, 04:01 PM
This is an old version, the last of my Gear Train versions... I could always go back to the gears, if I found an EASY/CHEAP way to make them, but the gears alone where costing MORE than $200 a set lol... and the kit price woulda went above anything anyone would have paid.

This is actually the current version... although there was a few small changes made since I made this image.


2009.10.19, 06:05 PM
Can it be possible to use the differential gear of the AWD Mini Z (MA010) - MD005 is about 630 yen (about $6) a piece, the pinion and spur gears (MD006) will be about 735 yet (about $7) a set(?) .... to bring down the cost.

With this set-up it can be an optional FWD, AWD or RWD with a mid motor mount.

2009.10.19, 07:05 PM
I cannot use a Kyosho DIFF.. its too big for the space I have left for my diff. :) My chassis is designed to fit around my special Diffs...

I am also hopeing for improved belt performance by using a special chemical that increases friction, but not adhesion for the belt drive. I still have yet to source the product from the person that has the copy rights though... it was a business teacher I had a class with in college, still have to make sure it will work the way I intend, and remember what that teachers name was... lol

2009.10.19, 07:22 PM
all i wanna know is.......

2009.10.19, 09:04 PM
It would be nice....

I litteraly have $0.00 though... so I cannot afford to build a prototype...
I may also be busy around the time of the race... but if I am I will have the money for the prototype then, but I would only have a week to take it from 3D cad drawing to actuall chassis, then fly to the race location.

2009.10.20, 09:58 PM
Very cool design for 1/28 scale. Since you can't afford to make one your self, have you thought about selling the design to either company of Xmods or to Kyosho? Or perhaps Team Losi? They should venture in the 1/28 scale and your design look's like it would fit with their other stuff I'd think.
I know there's nothing like making it your self, but at least your own design would be out there! Just a thought :D

2009.10.21, 03:42 PM
Very cool design for 1/28 scale. Since you can't afford to make one your self, have you thought about selling the design to either company of Xmods or to Kyosho? Or perhaps Team Losi? They should venture in the 1/28 scale and your design look's like it would fit with their other stuff I'd think.
I know there's nothing like making it your self, but at least your own design would be out there! Just a thought :D

yup... I think HPI would consider that too and probably even the chinese aftermarket makers like 3Racing and Din ball (aka RC Mart).

Din ball have this 1/24th scale mini-X that seems to be failure due to some material and design flaws of the product.

2009.10.21, 05:57 PM
That Mini-X was a neat idea, but it was junk. It was cheap clear plastic, ugly clear wheels, and way too heavy to be any good. Suspension was inovative, and well, it just sucked. LOL!
I bought one cause I liked the idea behind it and it was way before the MA010 was released. But, all in all it was a POS. This look's way cooler!