How to reinforce my universal drive shafts

[BigGinge]

Hi, I've taken my little XLF F16 buggy out for a quick lunch time blast these last two days and both times I've ended up with a 2wd car after running it for a few minutes (yesterday it probably lasted about 3 minutes, today more like 15). This has been caused by a 1.5 x 10 mm dowel pin in the universal drive shafts (used for both the front and back wheels) coming out so that there is nothing coupling the drive shaft to the wheel. The other wheel on the pair then gives up on trying to drive the car as the diff just spins up the split drive shaft.

 

I've managed to find a bag of 100 pins for not too much money, so the loss of the pins isn't the end of the world, but it is annoying having to fix this on the car so often and it would be nice if I could stop it. I was wondering if anyone here could offer any suggestions.

 

The 1.5 x 10 mm pins I'm loosing are held in place by a small coil of wire that is pushed into a groove over the universal cup. I'm not sure if this wire is shifting and allowing the pin to escape but given the rest of the assembly seems to stay in the correct position I suspect this is what happening. Does anyone have any suggestions on anything I could use to replace the wire coil (it would need to be low profile as it needs to fit into the car hubs) or to improve the retention of this on the drive cup?

 

 

[walkbythesea]

That’s a very common construction and I’ve never seen one come out before on anything - will watch with interest!

[Lone-wolf]

Heat shrink over the wire coil that tries to hold the pin in place

[BigGinge]

Heat shrink might work to keep the wire in place, I'll see if I can remember to pinch a bit that the right size for this next time I head into the office.

 

I was also wondering about the possibility of swapping the coiled wire for something like the a cir-clip or snap/retaining ring (see pictures below). I'm not sure that there will be enough space for the cir-clip but the snap/retaining ring would almost certainly fit. The only issue with the retaining rings will be finding something suitable in the right size (without needing to buy thousands of them); anyone know of any suppliers who might be able to help out with this? I have found one supplier in the US who seem to offer a part that would be a good fit for this but I'm guessing they won't want to sell me 10 of these.

 

https://www.smalley.com/ring/hsm-11

 

 

 

[DJFRC]

Hi BigGinge, just wondering if you found a solution to the wheel shaft issue on your XLF F16?

I've got the same problem with my XLF F18. The little pins dislodge and the universal dog bone shaft become two separate pieces. I've broken two in the last two weeks....starting to get a little pricey.

Keen to find a solution. Any luck so far?

Cheers,

DJFRC 

[BigGinge]

I picked up some heat shrink so I could try putting this over the retaining coil that holds the pin in  but I've not gotten round to actually trying this out yet as I've since built up a new LC racing truggy which I've been taking out in preference to the XLF F16.

 

I also ordered a bulk bag of the 1.5 x 10 mm pins that had been falling out so I could fix any drive shafts that failed as this worked out much cheaper than just buying lots of new drive shafts (and somehow all of the other bits always seemed to still be there when the pins fell out):

 

https://smile.amazon.co.uk/gp/product/B07MR3RD1B/

[DJFRC]

Heat shrink sounds like a possible solution. Thanks for the link to the pins. Much appreciated.

 

Where did you get the spec drawing you have in your original post?  (I haven't been able to find part numbers for any of the XLF F16/17/18 variants.

 

In my case, I'm losing the part labelled F16054 as well as the pin, so I'll need to find a replacement/solution to this part also.

You mention the pins are held in place by a small coil of wire. Is that the F16054 you're referring to?

 

Another idea I had was whether there might be another dogbone/CV joint component from a different RC car that might work as a cheaper replacement.....?

[BigGinge]

So, the little coil of wire is probably the F16077 on that assembly diagram, it wraps around the groove one the outside of the domed bit of the drive shaft to cover the holes used to install/hold the pin.
 

The diagram was just one In the user manual that came with the car but I didn’t have too much luck searching for parts using those numbers. I’ve not tried looking for replacements for the little F16054 parts so don’t know if you can buy those separately. 

I suspect there would be other, stronger, drive shafts out there that would fit but I have no idea how you would find them as I don’t think I’ve ever seen accurate specifications/drawings for any of these parts anywhere. 

[Tucker427]

I had the same problem and used thread-lock to solve it. Just be careful when applying it so you don't lock the whole thing up. 

[DJFRC]

On 03/10/2021 at 16:57, BigGinge said:

So, the little coil of wire is probably the F16077 on that assembly diagram, it wraps around the groove one the outside of the domed bit of the drive shaft to cover the holes used to install/hold the pin.

Nice one. Thanks for that. I hadn't actually noticed that those wire coils on the outside. I'll keep searching when time permits and report back if I stumble upon any similar parts and/or full assembly that would work as a substitution.

 

Tucker427, that's a good suggestion. Good to hear you've had success with it too. Perhaps that and BigGinge's great idea of some shrink wrap around the dogbone - CV joint section in question might prove to be pretty decent workaround solution. The combined result might be a significantly stronger joint, and might stop the bits flying off (i.e. help retain the 10mm pin and the F16054 part in place so it can be repaired again if/when it breaks again).

 

 

[DJFRC]

On 04/10/2021 at 04:52, Tucker427 said:

I had the same problem and used thread-lock to solve it. Just be careful when applying it so you don't lock the whole thing up. 

 

Tucker427, where exactly on the assembly did you apply the thread-lock? I used some today but had another break. Only lasted about 5 mins unfortunately.

 

Any assistance would be great.

 

 

I've borrowed BigGinge's drawings (thanks) if it helps explain the location...