SCX 24 - Layer by Layer

[Bray D]

Originally Posted by HumboldtEF

Just keep in mind the dimensions will change and some parts will warp a fair bit. CNC kitchen on Youtube has some good video's on Annealing.



https://www.youtube.com/watch?v=dOzVuoBP9gY

I watched a couple videos - looks like the dimensional changes are significant, but I could design around it for some parts. Still pretty awesome that you can change the mechanicals of plastic with such a simple process.

Originally Posted by chaotic_life

Thats pretty cool... would you mind sharing the STLs for the linkage?

I'm a stickler on protecting intellectual property, so I'd rather not distribute the files. I'd encourage the support of forum member RexRacer19 via his Shapeways store if you need to buy a set.



https://www.shapeways.com/product/PP...73656&li=shops

[Bray D]

Revisions. I didn’t like how chunky the steering links were so I modeled up a more aesthetic version. It’s definitely more svelt, which may prove detrimental at some point.

At least I have spares now, haha.

[Bray D]

The motor came in so I spent this morning stuffing that in there.

I scanned the motor plate, modeled it, and printed it. Bad idea. My nozzle is too big for the small features and there’s no way the plastic would hold up. This piece needs to be metal.





My next approach was to drill out the existing plate. I printed a ‘drill guide’ and gave it a shot on the big machine. Not my best work, but it got the job done.

[Bray D]

I had to trim the passenger side front leg off of the battery tray, but otherwise it fit great.



I also had to swap the pins in the plug as it was spinning backwards out of the box. Everything is moving the right direction now and the increased torque is noticeable. 100% would recommend this motor. Seems to be the same speed as the 88 turn 030 motor, but it definitely has more torque.

After that I swapped on the EMAX servo as a test run. As expected, it’s slightly longer and requires longer screws to secure it to the mount. I plan to make a new mount so I can use the original hardware. For now, longer screws works.






Plenty of room with the front crossmember. I’m not running a bumper though, so keep that in mind.




Noticeable improvement with this mod too. I think just having a fixed horn made a huge difference; the increased steering torque is icing on the cake.

It feels like a legitimate crawler now. Good low end torque and modulation. Strong steering. All good stuff.

I’ll clean up the servo install when I make a new mount. I’m looking forward to getting my receiver and Micro ESC installed too.

[Bray D]

I thought I’d start chipping away at the servo mount tonight and the next thing I knew it was done and printing. I’m not 100% sold on the print quality, but it assembled beautifully. If it fails I’ll make some adjustments and give it another go.













Still need to trim the steering horn and clean up the wiring, but it’s getting there.

With the servo mount printed and proven, I have a solid baseline for integrating link mount options. The gears are turning.

[Gramps]

That looks really nice. I've been working on one, but I made mine flat like the Hot Racing one. Still trying to get the geometry correct. What orientation did you print your at? I printed mine upside down with supports, so it doesn't clean up as well as yours.

Open up the Emax and shorten the wires, they are easy to get to, I made mine just a bit longer than stock. I had taken the yellow wire off before I took the picture, htis is the before picture.

[Bray D]

I printed mine with the servo mounting face flat against the build plate and used supports. I knew the back wall would be pretty grainy, but I figured that orientation would be best for ensuring the critical features were pretty solid. I still have some work to do to get my printer dialed in a bit more, but the piece works for now.

Shortening the wires and resoldering them to the board is pretty bold! I'll likely cut it down and build a new plug. I've done that in the past with success and it's lower risk with my skillset, haha. I'd like to wait until I get my receiver and ESC mounted to make sure I have sufficient length first though.

[Bray D]

My Sidewinder Micro 2 arrived today. It’s (comparatively) huge! It’s essentially the same size as the battery.

It has me second guessing my ambition to replace the 2in1 unit. It would be nice to be able to use my GT5, but I honestly don’t need any of the features it offers. They’re marginal gains at this point.

I may play around with sinking the existing electronics as deep into the chassis as I can and go from there. I’m not dismissing the Sidewinder entirely yet, but the size and required wire management isn’t appealing.

[PFongemie]

Originally Posted by Bray D

My Sidewinder Micro 2 arrived today. It’s (comparatively) huge! It’s essentially the same size as the battery.

It has me second guessing my ambition to replace the 2in1 unit. It would be nice to be able to use my GT5, but I honestly don’t need any of the features it offers. They’re marginal gains at this point.

I may play around with sinking the existing electronics as deep into the chassis as I can and go from there. I’m not dismissing the Sidewinder entirely yet, but the size and required wire management isn’t appealing.

The sidewinder micro fits great under the battery tray. Just a couple of zip ties to hold it in place. At full suspension compress there’s about a 1/8 inch of clearance.






Sent from my iPhone using Tapatalk

[Bray D]

Originally Posted by PFongemie

The sidewinder micro fits great under the battery tray. Just a couple of zip ties to hold it in place. At full suspension compress there’s about a 1/8 inch of clearance.

Nice! Thanks for the pics.

I talked myself off the ledge while at work and came home to see where I could put it. Under the battery tray will be perfect.

That leaves the factory esc/receiver tray open for the new receiver, but that’s no fun. I have a new receiver tray printing right now that will give me some more clearance with the body and drop the receiver down a bit. I’m anxious to see how it works out.

In the meantime, here’s some weights for good measure. The ESC is essentially the same weight as the battery. Mounting it below the tray will keep the weight low and the rig happy.












And a pic of the current state of the truck for good measure.

[Bray D]

The receiver mount turned out pretty nice. It still blows my mind how you can model parts, print them, and bolt them right on. It’s awesome.

I modeled the receiver with mock plugs in all 6 channels just for the space claim. I also put a slot in the plate so I could fish the steering servo wire through it for a direct path to the receiver.









I could move things a mm here or there to lower it a bit more/gain some more clearance, but it’s tucked in there pretty good as is.

I’m pretty much down to wiring at this point. I plan to shorten everything as much as possible in hopes of having a clean install.

I think the last decision I need to make before I do that is determining what plug I want to use for the battery. Deans seem huge. The PH2.0 seems small.

What are you guys running for battery plugs?

[HumboldtEF]

I'm using a JST plug for the battery. If thats too small for you theres the XT30 but I think thats maybe a bit overkill.

[Gramps]

I switched both of mine out to XT30 I cut the battery wires in half then put the XT30 connector on the ends. I now leave the PH 2.0 plugged in all the time.

[Bray D]

Thanks guys. I ordered some XT30's to see how I like them. If they're too bulky I'll drop down to JST.

[Damion10]

Forgive me if this has been asked / answered already , but are you going to share the files you came up with / 3d printed?

[Bray D]

Originally Posted by Damion10

Forgive me if this has been asked / answered already , but are you going to share the files you came up with / 3d printed?

I don't plan on it. Engineering isn't free, but engineering software is! Download Fusion360 and build whatever you need for your rig.

[Bray D]

I was less than impressed with my cut up stock foams, so I bit the bullet and ordered a set of soft micro foams from CI.

They’re so wide you can get two for one! Cut in half, they’re still wider than the stock foam. I was comfortable going a bit narrower than most since I’m on a narrower wheel as well.



These bad boys are soft. I like it so far, but we’ll see how they look once I build the rig back to full weight.




I also decided to make some changes to the servo mount. Note the high clearance mounting tabs and the notch at the rear to allow the servo wire to pass through more freely. It’s printing as I type.



Edit: print is complete. The clearance mods worked nicely. The receiver tray slides past the servo beautifully and there is plenty of clearance with the body posts.

The Y link is still rubbing the driveshaft though. I’ll print another one with that mount slightly higher to eliminate that issue. I know full axle compression is unlikely, but I’d still like to get it as low as I can for when I swap shocks. I may need end up running a super low ride height. Not sure yet.

[Gramps]

Your rrx tray does a good job of setting the rx lower in the chassis. Nice design

[Bray D]

Thanks Gramps. With how light this receiver is it’s almost pointless, but keeping it low should keep my body options open too. Building is a good chunk of the fun for me anyways.

I ended up making multiple servo mounts today trying to get that fitup perfect. The final version has shorter mounting tabs and a slightly higher Y link mount. No pics as it’s nothing too novel.

I’m splitting hairs with the rx mount too. I widened the slot a bit so the servo wire is more relaxed and added another shock mount. 20* laid back per CAD.




I made new rear shock mounts as well. These are essentially test pieces to see where I want the final location to be, then I can print some more aesthetic mounts.

These are 20* laid back just like the front. Unfortunately there is a fatal flaw both front and rear. The shocks pass directly over a frame mount screw that would hit the shock body if fully tightened. I’ll need longer bosses if I want to stick with the 20* orientation.





I designed these so the truck would have the same full compression stance as OEM. At this angle and spring rate, that could very well be ride height once I get the electronics on it, haha.

This shock work may have to wait until I get some longer shocks to play with. I need more flex!

[Gramps]

I saw where someone took screws from a servo, maybe a mini not sure, and used it as a replacement shaft in the stock shafts. It was on YT I think they went full droop and didn't use springs or maybe used some 3D printed collars.