RCCrawler Forums

Uroplatus

I wrote this for my site, www.ncrccrawlers.com, but thought I would share it here... easy how to with photos of doing a enclosed dig switch for the Berg or any other MOA righ.


MOA (Motor On Axle) Axles are great alternative to the Shaft Driven rigs out there on the market. Both seem to have there place in the comps and such. Here we will make a dig switch box for both front and rear dig.


You will need a few tools:

• Solder Iron and Solder
• Allen Wrench
• Philips Screwdriver
• Drill and 1/8th Drill Bit
• Dremel with Cutting Wheel

Other Items:

• Radio Shack 1x2x3 Project Box
• Radio Shack 275-0016 Switches (2)
• Deans Plugs
• 16 Gauge Wire
• Heat Shrink
• 4 M3x8mm Button Head Screws
• Micro Server
• Velcro and Servo Tape

We will start off with Modifying the Project Box. There are a few raised screw posts in the bottom that will need to come off. Use a Dremel cutting wheel to cut away the posts. These posts are on the bottom of the box and are very short. Don't mistake these for the longer posts that the lid screws to.



Should look like this:



Next lets place the switches. Put one of the switches in the box with the open end up and against one of the longer walls of the box. Mark the top lip with a sharpie where the notch in the switch lines up. Leave a little room for the posts on one side in the box so that you have room for the wires. You don't need a lot of space.



Now line the marks up on the out side of the box and on the switch and mark where you will need to drill 2 holes per switch for mounting. Repeat for each switch noting the direct each switch needs to be. Both of the metal tabs of the switch will face each other.



Now you will need to drill the holes you just marked for. Use the 1/8th bit to do this.



Next you want to cut the lip from the lid to ensure clearance of the switches.



Now that the box has been prepped, we can move to soldering the switches.

The following diagram was found on RRCrawler.com and should show you how it will be wired.



Lets start with soldering the ESC Positive Lead. When soldering wires to the switch, be sure to tin the posts and wires first, and don't let the switch heat up too much.





Now Note which side will be agianst the box and which won't. You will need to solder the wires so that the will stick out from the side and not straight off the back of the switch. This will ensure maximum clearance from the inside of the box. Solder the wire to the NC or #2 Post.



Eyeball the length of the wire and cut it. Solder it to the NC (#2) post of the second switch. Allow cooling between soldering to ensure the switch doesn't over heat.



Next solder the ESC Positive lead to one of the switches (doesn't matter which, but remember that will be the switch that the negative lead will come from for the ESC as well to help keep it clean).



Now cut a peice of black wire the same length as the red wire that joins the 2 NC (#2) switches. Solder one end to one switch on the NO (#3) post on one switch and the other end on the NO (#3) post on the other switch creating a jumper.





Now we will solder on the 2 motor positive leads to the switches. Each switch get one red wire soldered to the C(#1) post.



Now we will need 3 peices of black wire to run to each motor lead and the ESC lead. The switch that has the ESC positive lead will get 2 of the 3 pieces solder to it and the other switch will get 1. all get soldered to the NO (#3) post on the switch.



Now the switches are done. We will now mount them to the box.

Start by reaming the holes on the switch a little (not all the way through) with the 1/8th drill bit. You don't want to go all the way through, but enough to get the button head 3mm screws to start and tap them selves going in to the switch.



Now place the switches in the box with the metal tabs of the switch facing each other and screw in the screws to hold them in place.



Solder you favorite ends onto the leads. The red lead coming off one switch on the NC (#2) post and one of the 2 black leads coming off the post NO(#3) to a plug that will go to the ESC. Then solder one black and one red from each switch, posts NO(#3, black) and posts N(#1, red) to plugs for each motor.

Now its time to mount the servo. I used a micro Spectrum S75 and servo tape and placed the servo in the box with the arm set to nuetral and facing up in the box like in the next photo. You will also need to cut 2 slots oposite each other on the short 2 inch walls for the wires to exit the box. You will run your Motor Lead out one side, and the ESC, Motor Lead, and Servo Wire out the other.



With the lid off the box, adjust you end points on the servo so that you ensure proper travel as to not burn out the servo. Also you have your servo set on the transmiter in the desired direction that the switch travels. Also once you have your servo set, label each plug for each motor (front and rear) and go ahead and label your ESC plug so that you don't get things mixed up.



You are now ready to put the lid on. Screw the philip head screws in the lid and test to make sure noting is binding or hitting the lid. Make any modification needed if it does hit the lid bu cutting or filing the lid for clearance.



I used the Radio Shack Superlock velcro style fasternes to attach the box to the skid of my rig. Place a strip on the lid between the screws, incase you need to get back in the box at a later date.

Now mount your electronics to the bottom of the box and install in your rig upside down. Your Now ready to Dig!!



Any questions on this, feel free to reply to this thread. If you find anything wrong, or know of a better way to do somthing in this How To, feel free to reply to this thread and let us know!

Thanks

cartronicshn

Nice write up, and great pics

TheHeadHunter

Great Thread!!!!! thanks !!!!!

wrcfan29

nice write up, thanks for sharing that with us

pup

Dude that is a GREAT wiring diagram. Thanks

Good write-up, looks just like mine.

SuperBad

I'm going to Radio Shack tomorrow to get the box and some more switches to change mine...Nice write up Thanks

Uroplatus

Thanks guys!!! I am glad you like it ;)

tootallcrawl

yes very nice!!!

TheHeadHunter

sticky????

tedmales

I have this box sitting here on my desk, I have been looking at it for a week thinking I need to build a dig, and then you up and show me what to do. Great work.

dirtydirtysouf

man........that is one clean way to install a dig

'04 Rubicon

Very nice write-up and great pics. Looked at doing the same before making my dig units but that project box was too big for my liking. It takes up too much space in the smaller chassis's of today, got my whole dig unit in 1" x 1.5" space.

Uroplatus

I do have to agree with ya on the space thing. I had to trim it to fit in my chasis. I am running a 45mm skid, and the box is a tad bit to wide. I will look at making this smaller at some point, but my biggest goal here was having a back up dig unit incase I burned a switch and this made it pretty easy to swap out. You can consider this v. 1.0 Thanks on the comments!

toiboi808

nice write up with clear pics goin to have to try this out

Da Hermit

Very clean. Cleanliness is close to Godliness. Will have to try this one too.

jbrentd

Sorry if this has been asked before, but I'm just now starting to get ready for MDA/MOA's. In the diagram, it shows the positive lead from the ESC eventually going to the negative side of the front motor. Is that correct? And is there a brief way to explain that?

Uroplatus

One of the motors will have to spin opisite the other inorder to rotate in the same directions. Since the axles are reversed and not really mirrored one moter would turn backwards and one forwards. So if you wire the one that goes backwards backwards, it will run forwards... now did I confuse you?

jbrentd

Nope makes sense. Especially since the axles are pretty much interchangable from front to rear.

jombo

how does that work, in the diadram it shows when the switch is activated the positive is disconected and then the neutral is engaged. does this still give you dig or just free wheel . i am a bit confused here because i have seen it reversed with the positive activated to both positives and disconnecting the negitive wire. dont mind me i am just a bit confused here

Uroplatus

Basicly what I am reading with the switches and all is this... when the switch is open, it allows the power to run down the red wire, allowing the motor to turn. When you close the switch it dead shorts the motor which breaks the line of power running down the red wire. The motor locks, doesn't really free wheel due to the magnets in the motor. Open the switch back up and the motor is now running. Trip the other switch and the same thing happens.

All the switches do is break the line so that power can't reach the motor.