Papa's Switchback Sawback

[papabash]

I picked this little jewel up in a trade with Jeepiac last fall at Crawlapalooza.




Jon builds his rigs right, so I knew I could count on it being a solid little rig, but the stock chassis really limited performance and the geometry made for a ride that was too stiff for my liking. This will be my 'fun rig' so I don't plan to go nuts with modifications and performance, but I still want it to have a familiar feel and be able to do what I ask of it. I had one of CBE RC Fab's super nice cf Switchback chassis on hand, so I decided to see how it would line up and work on the Sawback.



Before installing the cf chassis, I painted the outsides of the rails with satin black. I'm not going for ultra-realism on this build, but it's scale enough that I wanted to cover the cf pattern.

[JatoTheRipper]

Are you keeping the leafs?

[papabash]

Originally Posted by JatoTheRipper

Are you keeping the leafs?

Actually, this is the 4LS model, so no leafs to worry with.

[Jeepiac]

I sure do miss Al! Glad to see you're going wild with this one. I always liked it, but the link geometry killed my interest in it. Gmade using the Sawback chassis for the Komodo and 4LS was a cheap way for them to get more rigs on the market and they failed with the suspension imo. Can't wait to see what you end up with. I'm sure it's going to be outstanding just like your other builds! Buford says to tell you hi and I think he's liking his new home and all the attention he's been getting.

[papabash]

Originally Posted by Jeepiac

I sure do miss Al!

I'm sure you do! He's in good hands now, though.

Glad to see you're going wild with this one. I always liked it, but the link geometry killed my interest in it. Gmade using the Sawback chassis for the Komodo and 4LS was a cheap way for them to get more rigs on the market and they failed with the suspension imo.

Yeah, the stock geometry was horrible and constantly binding. I wouldn't call what I'm doing "going wild", but it will drive like it should when I'm done.

Can't wait to see what you end up with. I'm sure it's going to be outstanding just like your other builds!

Many thanks sir; it's mostly your work, I'm just making a few adjustments here and there.

Buford says to tell you hi and I think he's liking his new home and all the attention he's been getting.

Okay, now that was just mean! I miss that rig, but I have no regrets, and am very happy having Al in my stable.

[papabash]

Body-off shot before the dismantling:

[papabash]

And the fun begins!

[papabash]

I did a quick search and asked my CBE team mates and, as far as I (we) can tell, I am the first to convert a Sawback over to the Switchback rails. If anybody knows of another one, please post up, I'd be very interested in seeing it.

[papabash]

While it was apart, I wanted to put fresh grease in the transmission and axles. I had also ordered Gmade brass tubes for the front axle.



After tearing everything down, I discovered that Jon had already installed brass tubes in both axles. No surprise there, I should have checked before ordering... Guess I'll be selling a set.

[Jeepiac]

I know a guy that needs a set of brass tubes for his blue Bronco that happens to have GS01 axles under it. I also know the guy who originated the overdrive mod for GS01 axles. so if you want to put a set of R1 gears in the front end let me know. Now that I think of it, maybe you should check the front diff first. It might already have R1 gears in it, I cant remember.

[papabash]

Originally Posted by Jeepiac

I know a guy that needs a set of brass tubes for his blue Bronco that happens to have GS01 axles under it.

The tubes are yours buddy, same address?

I also know the guy who originated the overdrive mod for GS01 axles. so if you want to put a set of R1 gears in the front end let me know. Now that I think of it, maybe you should check the front diff first. It might already have R1 gears in it, I cant remember.

The ring gears look identical front and back, so I don't think you did the overdrive mod on this one. I would be very interested in doing it though!

[Jeepiac]

Same address. I'll dig through the computer and see if I can come up with pictures of the gear mod. Send me your PayPal address and I'll pay you for the tubes

[papabash]

Originally Posted by Jeepiac

Same address. I'll dig through the computer and see if I can come up with pictures of the gear mod. Send me your PayPal address and I'll pay you for the tubes

Packed up and ready to go out as soon as I can make it to the Post Office. My work hours are the same as theirs right now, lol. Don't worry about the PayPal, they weren't expensive.

[JatoTheRipper]

Originally Posted by Jeepiac

I know a guy that needs a set of brass tubes for his blue Bronco that happens to have GS01 axles under it. I also know the guy who originated the overdrive mod for GS01 axles. so if you want to put a set of R1 gears in the front end let me know. Now that I think of it, maybe you should check the front diff first. It might already have R1 gears in it, I cant remember.

Overdrive on a Sawback. I'm all ears! Please share.

[soze]

Nice, can't wait to see what comes out.

[papabash]

Originally Posted by soze

Nice, can't wait to see what comes out.

Thanks, me either!

[Jeepiac]

I'm planning on taking an axle apart, getting some pictures and posting a short how-to thread for yall. Did my first conversion over 2 years ago and haven't had a single issue. Yall gonna feel stupid when you see how simple it is

I'm done hijacking your thread now, Dave

[papabash]

Originally Posted by Jeepiac

I'm planning on taking an axle apart, getting some pictures and posting a short how-to thread for yall. Did my first conversion over 2 years ago and haven't had a single issue. Yall gonna feel stupid when you see how simple it is

Well, that didn't take long. I'm sure a lot of people will be doing this conversion now, including myself.
Overdrive your sawback

I'm done hijacking your thread now, Dave

You haven't hijacked anything; you're the reason this thread exists!

[papabash]

Over the last couple of days I was able to get in and work like crazy to get this switched over and running again. The conversion process was surprisingly simple.

The Switchback chassis rails have enough adjustment options already built in that the Sawback skid bolted right up. The Gmade front bumpers mount directly to the GS01 chassis rails. Since I didn't want to cut the mounts off of the chassis, I used some SCX10 rail ends to mount my bumper (rear bumper to be added shortly). The Gmade skid is wider than the SCX10 pieces, and although the Switchback rails obviously don't have the hard bends made into it that the original GS01 chassis had, they flexed easily to still allow for proper installation. Jon put a lot of work into the body, so to give it some extra protection I mounted a set of SCX10 sliders. You can see how everything lines up here:

[papabash]

My goal with this build was to keep it as much Sawback as possible, while using parts I had on hand to improve performance. To this end, I even kept 90% of the original crappy phillips-head screws.

Here is a list of things that are no longer stock:

* I used spacers to extend the lower links a small amount so that the wheelbase is now 12" instead of the stock 11.3". Most of the extension was in front, to move the tires closer to the bumper. I also put a mild bend in the rear lowers for added clearance:



*I made new Delrin upper links to adjust for the longer wheelbase. I made the rears long enough to clock the rear axle back enough to line up with the bends in the lower links. I used bent rod ends on the back to give them enough clearance when the axle is stuffed up into the frame:



*Jon had already installed Gmade CVAs and clearanced the stock Cs and knuckles which greatly improved the steering angle. I also flipped the knuckles upside down, which gave them about a 10 degree boost in caster angle. Steering is pretty good now:



*I used SCX10 shock hoops for added adjustability and added a set of CBE RC Fab Shock Keys in front to get the ride height and shock angle where I wanted it:



*Jon had already installed SCX10 Wild Boar driveshafts. I assume he had a pretty good reason for not running the stock shafts. I intend to only run this rig on 2S lipo, so these should hold up fine.

*The stock shock springs were way too hard for my taste, so I ordered the optional soft springs for both front and rear. They made a world of difference and, along with the angles the shocks are now installed at, do a nice job of flexing. I also used spacers to outboard the bottoms of the rear shocks about 1/2" on each side.



*Front bumper is an optional Gmade part:
HD front bumper for Gmade GS01 chassis [J30006] : JunFac.com
I trimmed the ends off to clear the front tires at full turn and drilled 2 holes in the factory recesses. This picture shows the holes drilled before cutting off the ends:



This allowed me to bolt it up to the SCX10 rail end that I drilled corresponding holes in. This was a quick and easy way to mount the bumper:



*Jon had installed an Axial 27 turn motor, which I will admit I was a little skeptical about running. I usually upgade my motors without even running the stock RTR ones but, after driving the rig yesterday, I have to admit I was pleasantly surprised. I don't know how long it will last, but the torque, speed, and control-ability are all right where I want them so I will keep running it as long as it lets me.

*In order to get as much of the weight up front as possible, I made a quick aluminum plate to mount my battery and electronics to. I trimmed the stock mounting brackets off of the Gmade electronics box so it would fit between the shock towers and mounted it with Shoe-Goo. I made a simple aluminum brace to raise the plate enough to clear the servo when the shocks are compressed:



*And, of course, I had to add a set of Motoworx aluminum wheels. 1.9 9 Hole SLW Wheel
I added a pair of brass brake drums for weight and then wrapped them in Pit Bull Rock Beast tires (the smaller non-XL size). I used the stock Pit Bull foams which actually work quite well for this rig.