Garage Lcg Crawler Build

[Jimbobjr]

I'm going to start building a lcg crawler from scratch. The chassis, servo mount, links, body/bumper mounts, and sliders will be made by me in my small garage machine shop. Chassis will be flat rail, 7075 aluminum with an angled skid similar to g speed and pro crawler.

The trans will be Salinas, servo Holmes hobbys, motor Holmes hobbys brushless stubby pp, and esc will be the castle micro x.

For the axles I had my heart on the stock scx10 3's but they are hard to come by and very expensive when found. The aluminum offerings are too heavy for what I'm doing so I'm going with the much cheaper and easy to find trx4 axles. They are more bulky and steering is less than the 10 3 but I think I can get another degree or 2 of steering by altering the cvd shaft, cup and removing a little plastic...

I can't really do much until I get the trans/motor mount. Salinas makes them as ordered so idk...3 brothers is a lot more denero and they are out of everything...

This will be bought in stages. My gearbox and axles are on their way. My material for my chassis is here. Tires, shocks, electrics and body will be on the next billing cycle to try and sneak some of this past my wife.

 

[Greywolf74]

Good stuff!

 

[WickedFog]

This will be fun to watch! But you are going to make me wish I had a garage!

 

[Jimbobjr]

Got my first order of parts. Jenny's RC comes thru again. Trx4 axles, shocks, links and hardware. The links will be custom length so I will be using the ends and cutting these down. Maybe I can mod them for high clearance since they are the longer defender ones.
My trans is in the mail and also my losi springs for modding the trx4 shocks. Not sure about wheels and tires. I may get some canyon trail wheels/tires for 22$ from Jenny's and call it a day. After modding the tires I really dont see much difference between them, the hyrax, or trencher. Of course I wont have the comfort of over paying...dtr a will certainly use something better but will need the extra coin for other things...

 

[Edough13]

Looking forward to another of your amazing builds @Jimbobjr! Sounds like this is going to be an awesome crawler for sure!

 

[Jimbobjr]

Looking forward to another of your amazing builds @Jimbobjr! Sounds like this is going to be an awesome crawler for sure!

Thanks! This is a learning experience for sure. Kind of waiting for stuff to come in the mail. I did get my losi mini t springs to do my own version of the dixieland hobbies mod for full droop shock setup using the trx4 shocks. I used a fine sharpie pen for the spring keeper and machined a step in the shock bottom for the other end. Could not find any small plastic bar stock so sacrificed a couple sharpies...

 

[Edough13]

That's awesome! So what is the benefit of the short spring only up to the bottom of the shock body over the standard shock setup?

 

[Jimbobjr]

That's awesome! So what is the benefit of the short spring only up to the bottom of the shock body over the standard shock setup?

The travel is the same. With a droop setup the shocks are pretty much fully compressed. When the rig bellies out, if its spring corrected, the tires fall away looking for grip. This allows the truck to be low but not get stuck on everything. I'm certainly a beginner at this but that's the way I understand it. I can change them back to a normal spring if needed.

 

[Xraycer]

Canyon Trail tire fan here as well. I have a set of much, much more pricey Hyrax with dual foam set-up, and I really can't tell the difference either.

 

[Edough13]

The travel is the same. With a droop setup the shocks are pretty much fully compressed. When the rig bellies out, if its spring corrected, the tires fall away looking for grip. This allows the truck to be low but not get stuck on everything. I'm certainly a beginner at this but that's the way I understand it. I can change them back to a normal spring if needed.

OK I see what your saying again looking forward to the build as you always make some amazing custom stuff and awesome rigs!!

 

[Greywolf74]

The travel is the same. With a droop setup the shocks are pretty much fully compressed. When the rig bellies out, if its spring corrected, the tires fall away looking for grip. This allows the truck to be low but not get stuck on everything. I'm certainly a beginner at this but that's the way I understand it. I can change them back to a normal spring if needed.

Sorry I dont follow. Can you try and rephrase your explanation please? I'm also curious to understand that set up

 

[WickedFog]

Sorry I dont follow. Can you try and rephrase your explanation please? I'm also curious to understand that set up

Basically, with full droop, your shocks are 'just' fully compressed by the weight of the vehicle. When a wheel goes over a lower piece of terrain, the wheel drops down and a little spring pressure help push it down.

 

[Pat_ranch]

Having recently run klr voodoos, trencher crawlers, and cut canyon trails, I can say that I don't see a ton of difference in the performance. The spendier tires are better, but it's a small margin.

 

[Greywolf74]

Basically, with full droop, your shocks are 'just' fully compressed by the weight of the vehicle. When a wheel goes over a lower piece of terrain, the wheel drops down and a little spring pressure help push it down.

I kinda get that but how is making the spring only go half way up the shock any different than the spring going all the way to the top other than it seems like it would limit travel although I know Jim says it does limit travel. I'm just not getting how this works

 

[WickedFog]

I kinda get that but how is making the spring only go half way up the shock any different than the spring going all the way to the top other than it seems like it would limit travel although I know Jim says it does limit travel. I'm just not getting how this works

The spring doesn't limit the travel, the shock shaft does. In those two shocks, they are different size springs. I am guessing the shorter, smaller diameter one is a lot softer spring.

 

[Jimbobjr]

Sorry I dont follow. Can you try and rephrase your explanation please? I'm also curious to understand that set up

sorry...the guys above pretty much nailed it. The little springs are used because idk of any regular springs soft enough. Plus without the adjuster they can be mounted up side down for a little more lcg. The shocks still have all the travel, they just look like they don't. the front will be very soft and firmer in the rear. On a climb I want the front to stay compressed as long as possible before they release and rear springs compress.

I kinda get that but how is making the spring only go half way up the shock any different than the spring going all the way to the top other than it seems like it would limit travel although I know Jim says it does limit travel. I'm just not getting how this works

Theres not a regular spring I can use to do what I want this to do. Performance on steep hills/rocks and side hilling is what I'm trying to accomplish at the expense of trail performance. Keeping the rig low and light weight Instead of loading down with brass to keep all fours is what I'm trying to do. More or less learning as I go thru youtube and running my other rigs on the rocks. I don't really have anyone around to copy or get advice...in real life anyway...

I think the only thing that will keep this rig from being really good is the trx4 front axle steering angle. Most guys using portals on these run the axial scx10iii or capra axles. Some will even run a portal in the rear and scx10ii in front for an even lower front end and tight steering (the gearbox needs to be modded for this to properly drive both axles.) the trx4 cvd maxes out at 45 degrees. To make it better it have to relieve the cvd cup and ball in the lathe, shave off the stops on the boxes and c hubs and make a different drag link (stock hits the pumpkin, maybe it could be raised...). I think I will just leave it alone, get a strong servo and run with the locking/unlocking diff. I think it might steer a little tighter with the rear open. I really do not want the added weight and complexity of the servo but will give it a go.

I'm hoping my gear box and skid come tomorrow. I just saw team garage hacks new lcg gear box and its gorgeous. Kind of wish I saw it before the Salenas but it is I good bit more money. They look to be a copy of one another. Not sure who copied who... The Salenas has other gears you can buy to mess around with overdrive and also has a mirrored plate so you can switch it all around to run the motor on the opposite side.

 

[Greywolf74]

sorry...the guys above pretty much nailed it. The little springs are used because idk of any regular springs soft enough. Plus without the adjuster they can be mounted up side down for a little more lcg. The shocks still have all the travel, they just look like they don't. the front will be very soft and firmer in the rear. On a climb I want the front to stay compressed as long as possible before they release and rear springs compress.

Theres not a regular spring I can use to do what I want this to do. Performance on steep hills/rocks and side hilling is what I'm trying to accomplish at the expense of trail performance. Keeping the rig low and light weight Instead of loading down with brass to keep all fours is what I'm trying to do. More or less learning as I go thru youtube and running my other rigs on the rocks. I don't really have anyone around to copy or get advice...in real life anyway...

I think the only thing that will keep this rig from being really good is the trx4 front axle steering angle. Most guys using portals on these run the axial scx10iii or capra axles. Some will even run a portal in the rear and scx10ii in front for an even lower front end and tight steering (the gearbox needs to be modded for this to properly drive both axles.) the trx4 cvd maxes out at 45 degrees. To make it better it have to relieve the cvd cup and ball in the lathe, shave off the stops on the boxes and c hubs and make a different drag link (stock hits the pumpkin, maybe it could be raised...). I think I will just leave it alone, get a strong servo and run with the locking/unlocking diff. I think it might steer a little tighter with the rear open. I really do not want the added weight and complexity of the servo but will give it a go.

I'm hoping my gear box and skid come tomorrow. I just saw team garage hacks new lcg gear box and its gorgeous. Kind of wish I saw it before the Salenas but it is I good bit more money. They look to be a copy of one another. Not sure who copied who... The Salenas has other gears you can buy to mess around with overdrive and also has a mirrored plate so you can switch it all around to run the motor on the opposite side.

Still trying to learn about crawlers. I havent gone down that road yet. Maybe one day so I'm trying to study up on them a bit in the mean time. I understand what the mod accomplishes I'm just unclear on the exact mechanics behind it. What is that type of shock mod called? Ill do some google-fu on it

 

[WickedFog]

Still trying to learn about crawlers. I havent gone down that road yet. Maybe one day so I'm trying to study up on them a bit in the mean time. I understand what the mod accomplishes I'm just unclear on the exact mechanics behind it. What is that type of shock mod called? Ill do some google-fu on it

I have actually never seen anyone do that by using smaller shock springs. It is interesting for sure.

 

[Greywolf74]

I have actually never seen anyone do that by using smaller shock springs. It is interesting for sure.

I've seen it on a v1 Bully based MOA comp crawler that I bought from SlowNGreen here off the forums years back but I never understood why the shocks were that way. Plus I never got around to actually building that kit out. I ended up reselling it to fund other stuff I was more in to at the time.

 

[WickedFog]

I've seen it on a v1 Bully based MOA comp crawler that I bought from SlowNGreen here off the forums years back but I never understood why the shocks were that way. Plus I never got around to actually building that kit out. I ended up reselling it to fund other stuff I was more in to at the time.

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It has to be because you are using a much smaller, hence softer spring to get the droop.