Let's Talk Tractor / Truck Pulling

[morrisey0]

Anyone here into tractor pulling? I have been anxious to get into some sort of local RC competition, but 1:8 buggy racing is out of my skill set, and everything else is just too far away to justify getting into. But, through a FBMP deal this evening, I heard that there is a LHS that does pulls about once a month. Even I can build a rig and try to go straight until it stops! I have reached out to them through FB and am waiting for their response. But I am also diving into the research, and a little shockingly, it isn't all out there and obvious as I was expecting.

Being still a niche part of the RC world, I was hoping to approach it just as I did crawling 20 years ago .............. design / build it yourself.

I am leaning more towards a 2wd electric class, but haven't even gotten far enough it to know classes. I have seen some twin rear axle semi type rigs running also, which would also be up my alley.

Just wondering if anyone here is into the scene, and has any resources to share. The chassis and front look a bit open game, and a bit easy. The rear end types and gear ratios and such is what I want to learn more about right now. Many available chassis look direct drive, pan car like, but close ups and specifics look hard to come by.

edit: well, I found rules, so I will start there. http://nrctpa.org/wp/wp-content/uploads/2018/08/2024-NRCTPA-Dirt-Truck-and-Tractor-Pulling-Rulebook.pdf

[RC10th]

I'm watching with interest, surprised Lowgear hasn't chimed in.....

I've always enjoyed reading the RCCA coverage of pulling events but there was never anything local enough to me. I remember my LHS having an Astroflight Pullmaster motor in the case which always intrigued me.

Hopefully some more people respond to this thread..

[1911Colt]

I have nothing to add except that I am looking forward to seeing what you build. If the rules aren't too restrictive, I think you could make something pretty wild. I am picturing a circle of 4 or 5 motors all turning the same spur gear, maybe driving a scale looking Dana axle from a crawler.

[Lowgear]

I'm watching with interest, surprised Lowgear hasn't chimed in.....

Here I am! I just spent the last 7 hours working on the site, and it's now 8:00am here, and I'm on my way to bed.

I'll post more when I wake up but yeah... I have an unhealthy obsession with pullers. I've never pulled in a sanctioned competition before though. I'm more into the engineering and fabrication aspect of them. I've had a number of them over the past 20 years or so. I'm currently working on two, but I own four at the moment:

Sportsman / Open I class
Garden Tractor class
'90s Big Rig Carpet class
'80s Cox powered tabletop puller

[morrisey0]

Yay! Someone who knows what they are talking about!!

Sportsman or Open I is what I am thinking about after looking through the classes.

Of course I am going to try to make this as much of a parts bin build as possible, so came up with this out of spare parts. I think the frame will work out well, and was from an extra, unexpected slider that was thrown in on another deal. The front suspension will be greatly reduced or eliminated. Steering completely redone, and I think I can use the original tranny servo mount to help with this. Somewhere in some box I have an aluminum semi front axle. I have a deal worked out for some original white Clod wheels in the next couple of days, so my new purdy chromies can go on this. Also had an oddball, incomplete set of custom aluminum semi wheels that I picked up for near nothing that should work great on the front. I found an old Bolink funny car body that I thought was going to be perfect, but it is a little small for the task.

This is all the easy stuff I think. The rear end is a complete mystery that I haven't even thought about.

The local group is supposed to have a run this Saturday, but weather isn't looking awesome. Hope it works out.

[morrisey0]

So, from the very few pics I am gathering from the interwebs, the FDR I am coming up with 6" Clod tires, is in the ballpark of 20:1. I know nothing about what motors are being run in these scenarios, just that they are running double pinon-spurs, at around 20/90 each.

I decided to take inspiration from my Advanced Engineering dragster, and try to set this up with timing belts. The components are available, and just feel like it will be something a little different than the gear or chain sprocket setups. Obviously will need a thicker / wider belt type, so that will be an experiment. Hopefully I can design and print a "casing" for it all that will last more than a few seconds.

[Frankentruck]

It's like a Hyperdrive tractor puller!!!

[Lowgear]

Alright, I'm finally awake again.

There's a class for seemingly everything these days. They even have one for BoLink Diggers. Find out what classes are being run at your local event, so you don't show up with something you can't run.

I'll give you my personal take on pullings backstory, which may not be 100% gospel. Like with the rest of R/C, pulling had its heyday in the '80s and '90s. The majority of pullers were scratch built from aluminum, and there were only a few classes. Pulling was so popular at the time that it was enough to sustain the entire organization. After that, it started to wane enough where additional classes were occasionally added to keep interest up. It finally reached a point where that was no longer enough, so monster truck racing was incorporated into the fold. Now they've even introduced a demolition derby event into things. The NR/CTPA used to have their official forum on RCMT.net until it shut down a few years ago. We even had a dedicated pulling forum on ClodTalk.

Sportsman was always the most popular class in my eyes. They used to only run Clod sized tires like you're doing, but now it's become seemingly more popular to run Midnight Pumpkin / Lunch Box tires which are referred to as 'pumpkins.' As long as the tire is under 7" tall and 4 1/2" wide, you can run whatever type of V-tread tire you want in sportsman class. The two most popular axles sizes run are either 1/4" or 3/8" diameter. If you're going to run Clod tires, stick with 3/8" diameter as you'll have a good chance of bending anything less. That's if you're machining the entire thing yourself using no off the shelf pieces. Now in your case where you're using various kit parts, it may be the easiest just to implement an entire a Clod axle, with a gear reduction if you can.

You'll also need some kind of front weight which can consist of lead or steel suitcase weights or a weight box filled with weighted material. Additionally, weight is sometimes placed in front of the rear wheels to gain better traction. Speaking of wheels, you'll need to either glue the tires to the rims or run beadlocks. The tires themselves usually have the back of every lug shaved at an angle to cause a forward edged biting surface.

Pullers are always either gear to gear, shaft, or chain driven. I don't recall ever seeing a belt driven puller before. No matter how you do it, I don't think it's feasible.

[RC10th]

Correct me if I'm wrong but weren't the carpet big rig pullers the big daddy of the pullers?


Always wanted one of these..... still do

[morrisey0]

Yep, I stopped by the LHS this afternoon to gather as much information as possible, and again, what I gathered was not all that much. The guy I spoke with was into the whole thing, and ran a puller at their meets, but once I got a little technical, and mentioned things like FDR, he was quick to tell me he wasn't the guy to talk to about all that. He did tell me that if I show up to the pull this weekend, there should be plenty of people available to help me out with the technical stuff.

They had a Dirt 2wd up on the counter for sale, and bunches of rigs of different varieties in the back, so this was the puller place. He showed me a bunch of rigs in the back once I started asking about classes and such, and they seem to run a bunch. I found a puller bodied Sportsman on the shelf, and asked if many people ran that class, and he told me they did, so I am going to run with that for now. I found a Parma (looks to be re-pop) Ford puller body on ebay, and got that ordered. I do have another body sitting around that would be a little short, but maybe good enough to run the same truck in Open I.

I think a lot of the rigs that they run are made at the LHS, as I see a common theme in their FB page posts.

For now, I am just enjoying learning about it! What is ironic is that the wife and I passed a 1:1 tractor pull place while on vacation a couple of weeks ago, and I kinda had to explain the whole thing to her. Weird that I get introduced to the RC side of the same sport just a couple of weeks later.

[Lowgear]

Correct me if I'm wrong but weren't the carpet big rig pullers the big daddy of the pullers?


Always wanted one of these..... still do


DragginWagon.jpg

Yeah, I'd say there's a case for that. The carpet pullers in general pull much more weight than their dirt equivalents due to the superior traction surface. I could very well be wrong but it seems to be not nearly as popular as dirt pulling. Likely due to competitive carpet pullers having to be entirely scratch built for the purpose, where just about anything can be pulled on dirt with some modifications. The baddest pullers of them all as far as weight pulled is concerned are tabletop pullers. They can't be considered R/C though as they're not radio-controlled. They run on an elevated heavily varnished wood surface with silicone capped wheels. They don't have any steering, and are guided along with a 3-sided acrylic guide with handle. The operator holds that in one hand, and controls the throttle with the other hand via a tethered cable to the nitro engine. It's incredibly wild! The sanctioning body for them is the National Micro-Mini Tractor Pullers Association: https://www.nmmtpapullers.com/ I was just checking out their site, and now see they run electric pullers with an R/C transmitter for throttle which is something brand new.


The Draggin Wagon sleds had a cool look, but were mainly a novelty. They were string driven, and could only handle very little weight. The mass-produced competition sled back in the day was the MaxTrax Eliminator by Hobbico. Most sleds in pulling from then to even today are of the custom one-off built variety. Although there have been several attempts at low volume production runs to varying degrees.

[RC10th]

Well yes the Draggin Wagon is cheap but it makes a cool display piece and conversation piece.

Those table top pullers look serious

[Lowgear]

Tabletop pulling has been around since the '70s but you hear/read next to nothing about it these days. Not many people even know it exists. Seems to be predominantly a Midwest thing here in the states. The 'vintage' tabletop pullers were even wilder due to having no control over them besides being guided by hand. They all ran cox engines which where started wide open with no throttle control, and went full bore until they ran out of fuel like a tether car. The tractor varieties were converted from Ertl toy tractors with the treads ground off the hard rear tires to create slicks. Then they were soaked in things like diesel fuel to soften them up.

I have an early to mid '80s 4WD truck variety with an .051 Cox Tee Dee engine I have to restore one day in the next 100 years.

[RC10th]

Having a quick look and found this fun article on the 98 worlds....

On carpet

2wd Sportsman pulled 269.5 pounds
2wd Open I pulled 332 pounds
2wd Open II pulled 580 pounds

On dirt

2wd Sportsman pulled 60 pounds
2wd Open I pulled 90 pounds
2wd Open II pulled 120 pounds

[juicedcoupe]

For some reason, I like this idea.

http://www.rcsoup.com/2012/04/project-puller-converting-a-rj-speed-digger/

Maybe because it's simple and I have always been a fan of the Diggers.