Street S Maxx build

[Snook Man]

Back at the drawing board.
I’m designing a chassis for a custom Street SMaxx build.
Nothing extreme, but a different layout. I’m gonna try and make a recessed fuel tank up front so that it fits between the chassis braces. It will be extended front and rear with about a 16 inch wheel base.
Being 2 wd it will give me the room for the recessed tank and I may try to also make a center mounted steering servo if I can figure out the linkage and use a direct pull throttle.
Here is what I’ve got so far in the way of chassis design.

It should look similar to this when complete.

[Wolfslash16]

Good to see you again! I was starting to think you where going to leave us in the dark! Can't wait to see this one finished too! This is the first S-Maxx build I've ever seen, so this should be interesting. What car is that is the last pic?

[Snook Man]

Thats the custom chassis I built a few years ago. I used it for mock-up to see what the XO-1 wheels and tires would look like on a Maxx platform and to get an idea of the gearing I would need. I also wanted to see what kind of speed potential it would have with a good engine. I was pleased, so I started designing the chassis to fit the need for speed.

[Wolfslash16]

I'm guessing your refering to the 100mph car... Can't wait to see that one finished too...

[DBG]

Any Updates Snook?

[Snook Man]

Nothing major in the way of progress. I spent some of the day in mock-up designing a little different chassis since I had some free time.
Decided to go with a direct pull throttle and moved the recessed tank location further toward the front and worked out the linkage and clearances for the wider stance of the steering posts. I also decided to widen the distance between the front bulkheads so that a hump pack will fit comfortably between them to get some weight forward and low.

It will be a little while before I start cutting any aluminum for the chassis.

[stallion 63]

Hi Snook,what came of your 100 mph rocket?

[Snook Man]

The rocket is just sitting to the side for now, waiting for a body and springtime before anymore speed runs.

I did a little more experimenting with the layout and saw that I could mount the steering servo on the top of the front skid plate if I raised the tank up out of the recess a little.

Don’t know if I will go with it yet, just toying with the idea. It would leave me many more options with the chassis deck without a typical top mounted servo though.

[stallion 63]

Ok Snook,just keep us updated on the progress.Spring time?I thought you said in October?
You know that many like me have been waiting a very looong time to see that thing scream,right?In the mean time,pls keep posting the vids of your test runs.Cheers.

[Snook Man]

After a mock-up using 3mm aluminum plate as a 2 piece chassis deck, (1 front and 1rear plate with the center open to the chassis braces) and 2mm aluminum skids with the remainder of the truck being stock plastic 1 got a weight of just over 7lbs rtr minus the lid. With a few cutouts in the chassis plates I think I can get it rtr at less than 7 lbs.

[Nitronaught]

I was thinking,,, The motor mount/cradle could be dropped (probably tranny as well)... That would drop he COG a good deal if possible....

Looking forward to this and the Dragster....

[stallion 63]

Hi Snook,I was wondering why you had not designed your dragster and this street s maxx with laid down shock set ups as in the revo?I'm sure,it'll be a worthy attempt for someone with your skill level.Just something to keep your creative juices flowing!

[Snook Man]

NN, I’ve played around with the idea of dropping the engine and tranny lower before but the primary shaft bulge of the tranny is pretty prominent especially on the pipe side and the chassis braces need to be widened considerably to clear the bulge just to drop it 1 inch. Unless you can lower the tranny, lowering just the engine is not a viable option due to clearance of the rear shaft and gearing/mesh becomes an issue.
I would love to lower both but the extra bracing/mounting needed to lower the tranny gets complicated and ends up adding a lot of weight.

Stallion, I haven’t used the revo shock/push rod design mainly because of the space needed to make it work.
On the Dragster, my rear end was chopped considerably from stock and leverage comes into play with that type of suspension. The revo uses a lot higher shock spring rate than a maxx and when you shorten the a-arm length tuning the shocks with the correct springs and oil would be a lot harder.
I have run the Maxx and Revo set up for on road with the VD shocks & with the suspension squatted low and there really is no big difference between the 2 in handling on road when set up for it. The big difference with the revo suspension comes into play when you go off road.

[Snook Man]

Still playing with the design (since I’m stuck in Mississippi for the weekend).
This layout is more balanced and will allow for right or left throttle servo mounting for left or right side pipe, and either right or left steering servo position if I decide to change the steering servo mount on the skid plate to the upper deck.
Way too many options and decisions when designing the layout.

[Snook Man]

A little progress.

I have finally decided on the chassis shape and layout. I wanted it to be versatile so I again re-drew it.
Pretty much the same as before, but with a few differences.

With the fuel tank and hump pack in the center, the receiver box and throttle servo should offset the weight of the header and pipe and make for good balance all around.

I may sweep the front of the front plate back a little more but have to do some measuring to see if there will be enough clearance.



I mocked it up with thin plate aluminum and everything is working out so far. After a few tweaks I will start cutting the 3.5mm 7075 for the top plates and 2mm 7075 for the skids.

[DBG]

Looking nice Snook...
Wow...Another Novarossi? How many You have?
And what is the Part # of the receiver box?

[NitroTrout]

Looking good Snookman. Your chassis layout kinda resembles my pistol grip chassis.
Are those GA bulks you're using?

[Snook Man]

I pulled the Nova and pipe off the twin engine build just for mock-up to be sure a BB and big pipe would work with the layout and that there was sufficient room on the rear plate for engine mounting.
I haven’t decided what engine I will run but I should be able to fit anything I want from SB to BB.

The receiver box is just an old 2.5 box, part # 4924. I somehow have about a dozen of them so I thought I would put 1 to good use.

Those bulks are ACNCM, just for mock-up to keep everything aligned for measurements. The stock bulks (which I will use to save weight) are a little harder to work with during mock-up when your assembling and disassembling a lot and measurements tend to be more accurate with aluminum.

[Snook Man]

A little more progress:

I designed a new front plate with the front swept back and the steering servo mounting areas moved 5/8 inch farther toward the rear.
If I decide to use a top mount servo the spline is offset perfect for the stock steering setup.
I also worked out the skid plate mount steering servo setup. It works well and I have 4mm of clearance between the bottom of the recessed fuel tank and the top of the steering servo horn.
I have the front and rear top plates scribed for cutting and the skids are roughed out already. I should have some free time in a couple of weeks to start some assembling.

[DBG]

Nice^^^^^

Updates?

[Snook Man]

Front and rear chassis decks are rough cut. There almost as light as a stock 4910 chassis plate, with a little more cutting/finishing they will end up lighter.
Working on a new shock tower design to also be lighter than stock, and have a built in wing mount attachment.

[DBG]

Front and rear chassis decks are rough cut. There almost as light as a stock 4910 chassis plate, with a little more cutting/finishing they will end up lighter.
Working on a new shock tower design to also be lighter than stock, and have a built in wing mount attachment.

Nice...

I was looking this pic and i have a question...:



For what are you going to use those 2 holes? I dont think is for dual steering servos because after that pic there is another one with the steering servo...So I am a bit confused

[Snook Man]

Those locations are for mounting a steering servo on the upper deck like a stock maxx if I wanted to convert it to 4WD. I can use a single servo on either side I want and it makes the chassis lighter and more symmetrical with 2 cutouts.

[DBG]

Those locations are for mounting a steering servo on the upper deck like a stock maxx if I wanted to convert it to 4WD. I can use a single servo on either side I want and it makes the chassis lighter and more symmetrical with 2 cutouts.

Ahh, Ok thanks....

[Snook Man]

Got a little done today.

The front plate is complete except for a little trimming & polishing, I may also add a few more cutouts later but I will leave it as is for now.
I made a couple plastic brackets for securing the fuel tank to the chassis; I will trim them up a little also.
A top mount steering servo can be fitted to either side and the receiver box is also reversible to either side. Hard to see in the pics but I cut down the receiver box for a lower profile as well.
I may get to work a little on the rear plate tomorrow.

[sergio1]

The cuts are clean. what tools do you use?

[Wildman4910]

Lookin good!

[Snook Man]

The cuts are clean. what tools do you use?

I make the rough cuts with a jig saw with the aluminum plate(s) mounted to box/table with a sacrificial piece of wood under the aluminum.
Others have asked in the past so I took a pic of the table during the process this time.
I then finish the rough cuts to the scribed lines with an assortment of carbide dremel bits and sanding drums chucked in a drill press. With a good jig saw and blades you can get very close to the scribed lines with practice and leave very little finish work.



I trimmed up the rear plate today and did a mockup of the entire build using the aluminum bulks to get an idea of the actual weight. RTR without fuel and the aluminum bulks with a big ol heavy .28 on it; it weighs 7lbs 5 oz.
Not bad for full aluminum chassis plates, skids, bulks and braces and a 15 ¼ inch wheel base. The difference between stock bulks and aluminum is approx 4 oz so with a little more removal of material from the chassis plates I should be able to keep it rtr @ 7 lbs or a little less. If/when I add a rear wing, that will put me over 7lbs, but only by a few oz’s.

[danielhr77]

Subscribed! Very, very nice! Wish I could draw in 3D... And, check my 10x10 E-Maxx build...

[Snook Man]

I finally got the time to make the front and rear shock towers and a rear wing mount plate.
I did almost a full mock-up with a wing except for a few linkages for a weight check, and just as I suspected its well over 7lbs with the BB and wing (7lb 11oz). With stock bulks and removal of the wing it will save 9oz, but with a BB engine I don’t see me getting it under 7lbs without sacrificing some strength of the chassis components.
I have some new replacement parts on order and should be able to start the final assembly in a few weeks.

[Wildman4910]

Man that bad boy is going to fly.

I tried your box method for cutting out parts & I think I like it better then the band-saw I have been using.
Thank You for posting it.

[Redsawacs]

there is one among us who possesses serious skills!

Lookin good

[Snook Man]

While waiting for some parts on order I set up the throttle/brake linkage and made a easy secure way to fix the battery between the front bulkheads.

The throttle/brake linkage was pretty simple being the servo is on the passenger side with no fuel tank in the way and no bends in the linkage to clear the transmission housing.

To make everything fit as level as possible I added an extension to the top of the brake post on the transmission and cut the servo mounts down so the servo would sit lower to the chassis deck.
I made a custom angled horn from a round servo horn and added a small stainless steel extension to the end of the horn to attach a throttle return spring directly to the engine block (the Nova has built in spring attachments on both side of the block).



I stuck a HD self adhesive felt pad directly to the front skid plate for the battery to sit on and made a cross bar with a pad on the bottom that screws directly into the top of the bulks to snug up the battery. I made a cross brace from a wooden dowel that sits in the open holes of the bulks were the diff collar would be to keep the hump pack from having any chance of sliding back toward the steering linkage.
The battery is snug as a bug when installed but I can pop it out with 1 finger when the cross brace is removed.



Time to break it down and start polishing

[danielhr77]

Too nice! Are you going to use RPM parts?

[Snook Man]

I may use the rpm front bumper, but that would be it with this build.

[Snook Man]

Anyone have an idea as to why I did this?

[Wildman4910]

Anyone have an idea as to why I did this?

So you can straighten the angle out between the cups & dog bone.

[Snook Man]

Yup. almost 0 degrees at the diff. And after loosening the front screw, you can swing the cup downward and remove the dog bone without removing anything else.

[sefh]

Awesome design. I can't wait to see a video of this thing running.

[B3nno8]

looks awesome mate! wish I had the time and patience to do some thing like that. can't wait to see it up and running around