Xjeepguy
Super-Secret Yarmaluthe
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Well, now that there are 3 Groms in the fleet, it’s time to really start an official build on one of them.
I was tinkering with the green one, and installed shorter shocks, so that I can get that CG nice and low for the new carpet track at the LHS, and decided to go a completely different direction for the first official build. My builds always start the same way.
Yep. I measure everything I plan to replace or modify. This allows me to cross reference parts that may be made for other rigs, but may work on the project rig.
I usually use the “notes” app to record all of the info. I’ve learned that there are big differences between micro servo mounting tab placement, and that is something that can determine whether you can use stock mounts, or if you have to machine something or modify parts. The more research you do, the less chance you have of buying something you can’t use. Sometimes “factory upgrades” are nowhere near as good as something made for another rig, that can be adapted to the project. Never be afraid to modify stuff. Some of my best builds have parts that were never meant for it.
Have a detailed idea of what purpose you want the rig to serve, and what areas of the rig need improvement. In this case this Grom will have a lot of power. Seriously dude, a lot of power. So I took the truck apart and inspected the drivetrain. The factory plastic axles and hexes are fine for stock, or slightly increased power, but not where I’m going lol. So I bought this factory upgrade kit.
As you can see, it’s way, way better than stock. Many would argue that this kit should be stock on the truck, but you have to realize that this is a $130 truck, from a brand name company.
There was one issue with it, I got down to the last hex adapter, and noticed it would not fully seat on the pin.
Kind of a bummer, considering this is a $40 kit for a mini truck. I basically de-burred it with a hobby knife, until it fully seated onto the pin. You can see on the pic that the machining was sub-par. The other 3 were flawless and looked awesome.
I have a lot of parts ordered, and they’ll all be here by Wednesday of next week. Here’s what I have so far.
The motor mount kit allows me a lot of gearing options, without having to fire up the mill. I may still make a slotted aluminum one, mainly because I always prefer to set my own mesh. I went with a NSDRC servo, and put the Reefs back in the race buggy. I’m starting with an 18t pinion, but I’m sure I’ll be going higher with the motor/ESC combo I went with. If you are considering doing something like this, make sure you use a Mod .5 pinion. There are several pitch sizes out there, and you don’t want to get that wrong. The motor and ESC should be here Monday, and I’ll update the thread and show what it is. It should be a tight fit, and I may have to cut some chassis to get it to fit, but this thing’s gonna scream.
I figured I’d break the process down for the folks that are new to this sort of thing, and show how I go about starting a build.
I was tinkering with the green one, and installed shorter shocks, so that I can get that CG nice and low for the new carpet track at the LHS, and decided to go a completely different direction for the first official build. My builds always start the same way.
Yep. I measure everything I plan to replace or modify. This allows me to cross reference parts that may be made for other rigs, but may work on the project rig.
I usually use the “notes” app to record all of the info. I’ve learned that there are big differences between micro servo mounting tab placement, and that is something that can determine whether you can use stock mounts, or if you have to machine something or modify parts. The more research you do, the less chance you have of buying something you can’t use. Sometimes “factory upgrades” are nowhere near as good as something made for another rig, that can be adapted to the project. Never be afraid to modify stuff. Some of my best builds have parts that were never meant for it.
Have a detailed idea of what purpose you want the rig to serve, and what areas of the rig need improvement. In this case this Grom will have a lot of power. Seriously dude, a lot of power. So I took the truck apart and inspected the drivetrain. The factory plastic axles and hexes are fine for stock, or slightly increased power, but not where I’m going lol. So I bought this factory upgrade kit.
As you can see, it’s way, way better than stock. Many would argue that this kit should be stock on the truck, but you have to realize that this is a $130 truck, from a brand name company.
There was one issue with it, I got down to the last hex adapter, and noticed it would not fully seat on the pin.
Kind of a bummer, considering this is a $40 kit for a mini truck. I basically de-burred it with a hobby knife, until it fully seated onto the pin. You can see on the pic that the machining was sub-par. The other 3 were flawless and looked awesome.
I have a lot of parts ordered, and they’ll all be here by Wednesday of next week. Here’s what I have so far.
The motor mount kit allows me a lot of gearing options, without having to fire up the mill. I may still make a slotted aluminum one, mainly because I always prefer to set my own mesh. I went with a NSDRC servo, and put the Reefs back in the race buggy. I’m starting with an 18t pinion, but I’m sure I’ll be going higher with the motor/ESC combo I went with. If you are considering doing something like this, make sure you use a Mod .5 pinion. There are several pitch sizes out there, and you don’t want to get that wrong. The motor and ESC should be here Monday, and I’ll update the thread and show what it is. It should be a tight fit, and I may have to cut some chassis to get it to fit, but this thing’s gonna scream.
I figured I’d break the process down for the folks that are new to this sort of thing, and show how I go about starting a build.
