How to: Building custom width Twin/Mad Force axle
 

I'm constantly getting Emails and PM's about building custom width Twin axles. It's no biggie,just thought maybe if there was a thread it might help explain better and give people a place to ask questions. Mods,feel free to sticky this if you like.

First off,my pictures didn't turn out all that great so I just scanned pics from my manual to help with this. If anyone has any question,just post up and I'll try to answer. If somethings unclear,I can try to edit the steps to make it easier to understand.

The beauty of Twin/Mad Force axles,you can build dang near any width you want. As long as you have a dog bone that'll fit in the drive cups and stub shafts your golden.



Step 1. Assemble the center section with diff or spool inside and ready to run. (see picture below)

http://img.photobucket.com/albums/v7...iffhousing.jpg


Step 2. Insert the hub carriers as if you were going to assemble.


Step 3. Slide desired dog bone into axle tube and make sure it's all the way into the drive cup on the differential.


Step 4. Measure the distance between the pin on the dog bone and the knuckles pivot point. The knuckles pivot point is the hole that the 5mm bolt and collar goes through on the hub carrier(See picture below,red arrow). This distance is the amount of increased or decreased width you will obtain.

http://img.photobucket.com/albums/v7...cklecenter.jpg


Step 5. To decrease width,it's simple. Just cut off the measurement you got in the previous step from the assembled diff housing in step 1 and assemble the axles.


Step 6. To increase width,you will need extra hub carriers. Depending on how wide you go will determine how many extra hub carriers you need to buy. I believe you can get an extra 2 inches or better with each hub carrier. If you want to gain 1" of total width and put the pig right in the center of the axle,you'll need 2 extra hub carriers(1 for each axle). In my honest opinion,adding roughly 1" of total width and running 2 long side axles is about as wide as you'll ever need. Any wider and it gets a bit to wide.


Step 7. To add the extra width,pay no attention right now to the smaller section of tube(the section that slides inside the outer axle tube). From the spot where the tube changes size,measure over towards the hub carrier(remember the measurement you made?) and make your mark(See picture below). Cut this section off a hair big and sand with a disc to the exact distance then clean edges with a file or sandpaper. Make sure you don't cut to small,if you do,your screwed and that piece is junk. If anything,leave the cut piece a hair big. Even if it's an 1/8" big thats O.K.,we'll deal with that in a bit.

http://img.photobucket.com/albums/v7...winknuckle.jpg

Step 8. Now slide the cut piece into your assembled diff housing assembly and either CA glue them in or screw together. I've used screws to do this and I've used CA glue also. Either way seems just as good as the other and I've never had a tube fall apart.


Step 9. If your gonna glue these together and still run the factory 2 link arms for link mounts or servo mounts,better install them now. Now we'll slide the final and outer section (hub carrier) into the cut section and attach with either screws or CA glue.


Step 10. Slide your new dog bone into the axle tube and make sure it's all the way into the drive cup on the diff. Once installed all the way,see how the pin on the dog bone lines up with the hole in the hub carrier. It should be centered with the hole. If it's to short,don't sweat it,if it's about 1/8" to short,just take a ball point pin apart and cut about 1/8" off the spring. Dip the tiny section of spring into grease or Vaseline,this will help keep the spring on the ball while sliding down the axle tube. Attach the greasy spring to one of the balls on the dog bone and slide the dog bone (springside first) down into the drive cup on the diff.


Step 11. Now you can assemble the rest and put your knuckles,wheels and tires on and your ready.


Step 12. Double check all your joints,weather you screwed them together or CA glued them,make sure everythings tight and commence the rest of your build.

Thanks man..i was just about to start a search and youve already answered my question.

could you use a sleeve that fits tight over the original housing and glue them together? im thinking like pvc pipe or aluminum turned down.

Well,I guess you could. Adding thickness to your axle tubes will give less ground clearence. You also loose the factory link/shock mounts that are on the collars.

It could be made to work,but not the route I would take.

nice write up. surprisingly easy to adjust width, shame all axles wernt like that.

Thank you. IMHO,the Twin/Mad axle is a perfect axle for shaft driven crawlers. Tougher than crap,dang near any width is doable and can be built for both classes. They are the Dynatrac Pro Rock 60 of RC crawlers.

do they still make the twin/mad forces? i think i saw them on towerhobbies but there were like $300 or somthing is that a good price? or is there a place i can buy just the axles

I've heard they are still making the Twin Force Spirit,same truck but with carbon fiber chassos plates,but have yet to see one. They are a bit higher than the regular Twins. I'm hoping for a new release of the Twin. Gotta few builds I wanna try and will need a couple complete kits sometime this winter.

The best place or way to get Twin/Mad axles is at RCP Crawlers That is a smoking deal. RCP can get anything Kyosho,so you could get the tranny or anything else all in one place.

ok cool ive been looking for a pair of wider axles for my 1/6 scale body i have and i been going back and fourth between the forces and the wk

i went to hobbytown here in town and got the housing and knuckles for $75. the housings were like $12 for the outside half of the sleeves.

so on your 2.2 hustler did you do custom width or narrow/narrow? If you did custom what dog bones did you use? Also are there CVD's for them or are they just not needed? Stock do they get enough steering?

Currently,I'm running 2 shortsides in each axle on my 2.2 Hustler. I am though looking at a few options to get a skinnier trac width. I'll post up the widths and numbers when I get more info.

Stock,the Twin knuckles do have a pretty good throw to them. On my super,with stock knuckles,I can turn it 180 degrees in just a hair over 3 feet

Thanks!!....can you run 12mm hexes on the tf axles? where do you find 2.2 wheels in 14-17mm hexes??

You can drill the 12mm hexes out for an 8mm stub but they get thin. I kept cracking mine after applying a little power to them.

For my Hustler though,I took a set of flat maxx wheels and cut the center out to fit inside a Pede wheel. Then,I cut the factory center out of the Pede wheel and glued the maxx center in there. Walla,2.2 wheel with a 14mm hex. I was worried about it failing,so far,it's done great. No signs of weakness yet. Once I get a few things wrapped up on my super,gotta get it ready for the Nat's,I'm gonna concentrate on building my own wheel. Might look into having a set custom machined,not real sure yet.



We NEEEEEEED 2.2 wheels with a 14mm hex. Common guys,build us some good strong wheels here. 14mm hexes would be allot stronger. Since they come on the WK's and would easily adapt to a TLT stub.....WHY NOT?:lol:

Unimogger is making some ericksons with neg back spacing for 2.2 clods and WK's maybe we could get him to do a few with 14mm hexes, couldn't be that hard to make the hexes bigger;-);-)

I'd be down for a sets after the Nat's. That is if the back spacing is correct.

I just pm'd him...I think he is out of town for a while, probably the more that ask the more likely it will happen;-)

please pics, dont understand all of the mod.

peter

What exactally don't you understand?

So If I use 2 short side axles on one housing will that be within comp specs for 2.2 class width? You answered tons of my questions with this one post Raptorman"thumbsup" I'm sick of breaking TLT axles and dont want clods again.