FanRC FR01 TEN4.1 (Revised)

[morrisey0]

I had to revise this conversion because I was writing it out in order that I was doing it, but half way through, realized I needed to build it backwards, so I wanted a build thread that more accurately shows my method for going about this conversion. It will probably still be a bit choppy, and there will be pics that won't look in order, but it should be fine.

So with the FR01 and TEN 4.1 conversion kinda coming out about the same time, it felt only natural to me that they should come together.

I haven't done a full write up build in awhile, so here goes one.

#1 The TEN 4.1 conversion kit is not designed for carbon fiber chassis per FactoryWorks. For liability sake, I will say the same! So, let's build one.

You will need:
* FR01. The chassis will need to be stripped of all its sub-assemblies; down to a bare chassis.
* If your FR01 is well used, maybe you want to get bearings for the transmission? You are going to be in there, so might as well if you have some time on the rig.
* TEN 4.1 conversion kit from factoryworks.com
* Traditional 6565 style stealth transmission case. Your stock FR01 case will not work. Everything else in/on it is fine, but the case halves themselves won't work.
* Really just an extension of the above. You need those four motor mount spacers for the 6565 style trans case. Your FR01 didn't use these.
* A standard 2.25 stealth differential (separate from the one that is in your transmission). This is not in the pic below as I forgot I needed it and forgot to rebuild it before starting.
* RC10 aluminum nose piece (temporarily). Preferred junk one that can be sacrificed, but if you are gentle, you can use one and not destroy it (not my style)
* 4wd wheels and tires (the ones in pics are just super cheap ones I got just to have something to put on, they are not permanent)
* 100* countersink bit. Not in pic, but you will need one. Remember 100 degrees! The ones in the big box stores won't work unless you want to change all the fasteners.
* Standard drill bits (mainly 9/64 and 5/32) and hex drivers and all the normal building stuff.
* Drill press preferred, but may be able to do it with hand drill
* (2) 8-32, 7/8", 100* countersunk SS screws. You can build without these and easily swap later. But order them so you don't forget.
* (2) 4-40, 3/8-1/2", countersunk screws
* (1) 8-32, 1/2", 100* countersunk SS screw. This isn't really necessary, but RC10 guys have them around, so grab one if you got one.

[morrisey0]

Please do not take what is in the thread as a complete setup manual for this swap! Read the FTW manual thoroughly! This is not a substitute for the manual! Many things are missing in the posts that you need to read about in the manual. I am mainly pointing out the changes needed to do this swap on a FR01, not everything that you need to know about the kit.


For the FR01, we are going to start with the front end of the car instead of the back, like the manual does. The reason for this is that we are going to be drilling and countersinking holes in the chassis, and it is much easier to do this with a blank chassis than one with stuff attached. Any chassis that I work with that I want to keep nice, I cover with masking tape while building, and for this drilling process, I am going to be flipping this over so both sides will be hitting surfaces, so I covered both sides. This also gives me a surface to remind me what side I want to countersink, because yea, I would be that guy.

You are going to want to drill holes in the chassis to match the holes that are located on a stock aluminum nosepiece. There are different ways you can line all this up, and my method is easy, but it will probably mess up the threads in the holes, so don’t use my method with a good nose piece that you want to keep. Use only a junker. If you don’t have a junk one, use a good one as a template to mark holes, and then drill from there after removing the nose piece.

I also recommend a drill press for this to keep it all straight, but you do you.

Attach the aluminum nose piece to the chassis as shown. I just threw a couple of nickels in there to hold the nose relatively parallel to the chassis. You will need to drill the outer holes behind the ones that are there, and the two center holes. Use a 9/64” bit to drill out the holes using the nose as the template. While doing this, there is a good chance you are going to screw up the threads in hole(s) of the nose piece, so this is why you may want to use a junk nose if you go this route. From here, remove the nose piece, and drill the holes out to 5/32”. Then countersink the holes on the bottom, ON THE BOTTOM, with a 100* countersink bit.

Quick note here. For my build, I am simply taping down the steering servo. If you would like to fasten yours down, you need to figure that out about now. The stock holes will not work, and you will need to rotate the servo so that it is perpendicular to the chassis. If you want to drill servo mount holes, I would leave the masking tape on, and temporarily install the bellcranks as in next step. Then you can figure out your mounting locations, and drill and counter them now instead of when it will be more difficult in the future.




That was it! That was the hardest part of this conversion. The rest is mainly just building.

[morrisey0]

Next is the bellcrank and the belt tensioner. For the bellcrank screws, use one of the longer ¾” screws for the right side, and preferably cut the other ¾” screw down a couple of threads or so, or use one of the 5/8” screws. If you use the full ¾”, it will hit the tensioner, but the 5/8” doesn’t get all the threads in the top plastic nut, something that sits flush at the top of the plastic nut is what you want (my screw sits a little high). Everyone has those wire cutters with the bolt cutters built in right? Then for the belt tensioner, use the 3/8” that was with it in the front, and for the rear, grab a ½” SS 8-32 screw from your personal stash that every RC10 owner should have. If you don’t have any, just use the other 3/8” there.

Grab your front suspension assembly, and remove the shock tower and install the 4-40 3/8-1/2” countersunk screws in the blocks where the old screws were. Remove bottom shock screws, remove shocks, reinstall screws. Remove one e-clip from each outer hinge pin, and remove it. On the arm mounts, drill out the inner holes to 5/32”. Now install arm blocks and arms on vehicle, and install the outer screws. Remove all the ball ends from old steering / suspension components and move them over to the corresponding components on the new set up. Pic shows hex head shock tower mount screws installed; those should be the CS ones. Set the chassis aside at this point, and build the front sub-assemblies.

[morrisey0]

Front transmission. The front trans is simply a drive gear driven by the belt pully, and that spins the differential. It is just like the rear without an idler. I did have a bit of endplay on the drive gear this time around, and one shim per side cleaned it up nice.

I did run small issues with drive / idler gear shaft. 1) it seems that maybe during the drilling and tapping, it expanded a little at the end of the shaft. Not a biggie, easy filing got it straight. 2) the hole for the roll pin is just ever so slightly off center, which leads to it being difficult to get the pulley on. I test fitted the pin to pulley before installing it on the shaft, and they fit together great, but once the pin is in the shaft, it rubs up against one side of the pully groove just a little. Being a bit of a bull in a china shop, I probably didn't choose the best route here, and I went with the vise pressing technique, and I had to go a little harder than I wanted, but it worked fine. Taking it apart may be a different story.

I am not knocking the kit at all here!!! The manual makes it very clear that this kit is for builders with plenty of experience in building RCs, and this is part of the reason why. This is all custom stuff here, and sometimes custom stuff needs a little tweaking to make work. I fully expected things like this from the very beginning, and there will probably be more. This kit has done nothing but impress me so far!! Edit now that it is done, no other real issues found!!

Next was front CVAs and steering knuckles. I have a 50/50 shot of getting this correct, so it is probably wrong, but seems right so far. (Edit, this is correct) Hardest part here was the 12mm hex keeper screws, which should be the simplest. You have to find a phillips screwdriver that is small enough to fit, but has enough of a handle that you can torque a little. Then, please put the hex in the vise (so it is only gripping the bottom part), and torque down on it there. Don't try to hold it all in your hand and torque it down. That has putting a hole in your hand written all over it. You have to torque these quite hard to get them to clamp.

[morrisey0]

Now, put the front transmission in place and use the provided ¾” screws from the bottom through the [drilled] blocks, and into the transmission. Since our chassis is a little thicker than the intended one, with the ¾” screws, there is still about 1/8” of thread space in the transmission mount, so swapping these over to 7/8” is recommended (remember, 100* countersink).

Swap everything from the old shock tower to new. Use the top middle holes for the shocks, and the most inner holes for the camber link ball ends. Then install the outer steering setups in the outer hinge pins. You will need to adjust the camber links, but they will work and you can eyeball it for now. The steering links will need to be adjusted in about as far as they can, with maybe a thread or so for adjustment later. Install the shocks, blab la bla, just put it all together as usual ………………. except there are driveshafts and a transmission there now. Note that for right now, and maybe permanently, the servo is taped down. I did not drill for fastening the servo down. I need to add a note to an earlier post about when you would want to do this if you did want to.

[morrisey0]

Now we move to the back. You will note in many of these pics that there is nothing on the front. That goes back to me doing the back first, and then reversing that and starting in the front.

First is the rear bulkhead. This is all straightforward. The screw is already installed on the bulkhead, so just loosen it and install the two 1/8x5/16 bearings, and reinstall screw. Install the new shock tower as you would normally, while lining up the hole for the belt with the bulkhead. Swap your camber link ball ends to the bulkhead, but you will be changing holes (well, if you used the innermost holes under the wing tubes like I did during the original build). You will now be using holes in the location that they should have been on your FR01 originally, and I am pretty sure the camber links will like these holes better as they were stretched a bit far for those inner holes. Remember that the FR01 didn't come with the proper Worlds holes drilled, and this bulkhead has them. I will update and verify this in a couple of steps when the rear end gets put back together. With that, install the new bulkhead and tower using the stock hardware.

The rear transmission. Take your old transmission apart and set the case halves to the side. My FR01 was new, so I saved and reused the bearings (you will need the two in the old idler gear). On the left side replacement case, you want to install a bearing where the idler pully was (the middle gear), and use the bearing as a guide to drill a 3/16" hole through the case. Then remove the bearing and ream the hole just a little (manual says drill bit, unibit, or exacto knife). I just grabbed a body hole reamer and gave it a couple of twists on each side of the hole, and the new idler fit nicely. At this point, you are just putting the case back together with the new idler gear in place of the old. Remember you will need those motor plate spacers. When done, you are checking for free play at the idler, and installing shims as needed. Mine ended up with hardly any play without any shims, which means I probably did something wrong, but it seems right so far.

[morrisey0]

I think I had my rear shocks set up per the World's manual, and the inner holes on the TEN 4.1 shock tower are the same width as I had them set up on the FR01, so inner tower holes and outer arm holes should be right, but I may be off there. It is good enough to start with either way.

And with that, install the belt, and adjust the tensioner, and you are basically done. You will need to adjust your camber and caster links of course, but the stock links still work. I do have an interference issue with the belt hitting the battery hold down strap, even with the tensioner set higher than I want it. I'll need to figure out something there.

[morrisey0]

I made up a quick 2mm spacer for the belt tensioner, and the belt now clears the battery strap, but it is a little tighter than I am really comfortable with. A belt with one more tooth (3mm longer) will be here in a couple of days. If you space up the tensioner, remember to go with longer fasteners.

[GoMachV]

Sorry just got back home from a long weekend, yeah the spacer would be needed since you are missing the step that a bolt on nose plate has. The build looks amazing, nice work!

[morrisey0]

yeah the spacer would be needed since you are missing the step that a bolt on nose plate has.

Yep, and the longer belt is needed because the kickup on the FR01 is more forward than the aluminum tub, hence the aluminum nose piece can "small spoon" inside the FR01 kickup while mounted to the same bellcrank holes. With the more forward kickup plate, the front transmission ends up being mounted more forward as well, ergo a longer belt is required.

Not needed I don't think, but as I wait on some parts and such, I keep thinking about a spring loaded tensioner.......................

[Frankentruck]

Is a spacer needed under the front gearbox too? The spacer under the tensioner looks like it puts the lower belt run very close to the upper run.

[GoMachV]

chassis flex would definitely be less of a concern with a loaded tensioner, but the top belt needs to be direct as its under tension, and not a lot of room to play with the bottom belt. Something in a compound pulley arrangement with a torsion spring might work but would be a super tight fit.

I will say too that the the old mip cars tended to skip the belt and I suspect thats how they ended up with a front slipper at the end of its production run. I would run the front diff a tad loose to allow a slightly bit of slip. You are looking more for front wheel assist than a front wheel drive car dragging the back half around.

[morrisey0]

Is a spacer needed under the front gearbox too? The spacer under the tensioner looks like it puts the lower belt run very close to the upper run.

There is a decent gap there now, and with a longer belt (if I go that route), it will probably end up even closer because I will probably end up raising the tensioner more. Static should be worse case scenario for how narrow this gap should be, so running them closer together shouldn't be an issue. Speaking from my minutes of experience. If they hit, I am sure they will tell me.

I did get some electronics in my rig this evening. Original plan was brushed, then brushless, then went back to brushed. For what this rig should end up as, I think some solid NIMH / brushed runtime is all she needs (the 5Ks may be a little long). I loved that my ESC used blue / yellow motor wires, because let's be honest, that is what should be on a FTW motor!

[mikea96]

Looks really good! I really need to get the last few things for mine so I can start building it.

[morrisey0]

Got the longer belt in, and without adding another idler or something, it is just too long. That extra 3mm makes a lot of difference.

So, just going to run the original set up for now, and I think it will work just fine. The lower belt is probably going to ride on the battery strap some, but don't see an issue with this really. This is with a 2mm spacer under the tensioner.

Got in some 807C wheels for it to try them out. I am playing around with different thicknesses of adapters. I think they will be great so I have some 807C tires coming in also.