Senton Slipper Clutch Won't Tighten

[305HemiGuy]

Hey guys, from what I've read the slippers on the 3s line seem to be a weak spot. Looks like I finally broke the slipper on my Senton. When I give the truck throttle it doesn't move, I just hear the motor spinning up, and if I turn the center driveshaft by hand all 4 wheel rotate as they should. I tried what the Arrma manual suggests and put a wrench in the little screw inside of the slipper while rolling it, but the wheels won't ever firm up or drag on the carpet, they just keep rolling with little to no resistance. I think I have an extra slipper clutch repair kit laying around. Could someone tell me the exact item out of that kit that is needed for the repair, or do I have to buy a whole new slipper assembly? Also, what do you guys recommend to minimize slipper clutch issues? Thanks.

 

[SrC]

I feel the 4x4 slippers will always be one of several 4x4 weak links. Seems they work or they don't. Being a slave to tinkering with them at times.
I would just get a complete Slipper/Spur from JennysRC. and move on. Maybe buy 2 of them. Keeping a spare, you will most likely need it.
Have many rigs with slippers here. I gave up on Slippered rigs for this reason. Won't buy another.
Perhaps get a complete $4s$ 4x4 slipper. IDK.

 

[AIan]

It depends what broke in the slip assembly you need to take it apart to find what broke. Could be the little nut or the metal inside itself.

 

[305HemiGuy]

I feel the 4x4 slippers will always be one of several 4x4x weak links. Seems they work or they don't. Being a slave to tinkering with them at times.
I would just get a complete Slipper/Spur from JennysRC. and move on. Maybe buy 2 of them. Keeping a spare, you will most likely need it.
Have many rigs with slippers here. I gave up on Slippered rigs for this reason. Won't buy another.
Perhaps get a complete $4s$ 4x4x slipper. IDK.

Fair enough, I'll grab a couple of slippers and keep it moving. Sounds easier to just drop in a new slipper instead of tearing it apart every time it breaks. Conversely, if they tend to break often then that method could prove to be costly in the long run. Guess we'll just have to see. I also wasn't aware that the 4s slipper/spur assemblies were different, I'm sure the 4S assembly could hold up the stress better than the 3S assembly. You learn something new everyday here.

 

[AIan]

 

[305HemiGuy]

It depends what broke in the slip assembly you need to take it apart to find what broke. Could be the little nut or the metal inside itself.

Thanks for the video! If I can find the slipper repair kit in my bag-o-tools then I may open up just so I can finally use the kit. I bought the kit by mistake, just never returned it b/c it was only $6. Maybe I can finally get my money's worth from it.

 

[~Kaos911~]

Not sure if this helps, but knock on wood I have not had any issues with my slipper since. The last time I had issues, I replaced a seized bearing and pads, I put some loctite on the screw before putting the slipper assembly back together. I then did the "drag" method of tightening up the slipper. I double check the tightness before each run to make sure.
Be sure to inspect your assembly for cracks in the metal hubs as well as "burnt" pads.

 

[Velodromed]

Hey guys, from what I've read the slippers on the 3s line seem to be a weak spot. Looks like I finally broke the slipper on my Senton. When I give the truck throttle it doesn't move, I just hear the motor spinning up, and if I turn the center driveshaft by hand all 4 wheel rotate as they should. I tried what the Arrma manual suggests and put a wrench in the little screw inside of the slipper while rolling it, but the wheels won't ever firm up or drag on the carpet, they just keep rolling with little to no resistance. I think I have an extra slipper clutch repair kit laying around. Could someone tell me the exact item out of that kit that is needed for the repair, or do I have to buy a whole new slipper assembly? Also, what do you guys recommend to minimize slipper clutch issues? Thanks.

Have you opened the power module to make sure that the spur isn’t stripped or the pinion moved out of alignment?

 

[Surchaufeur]

If it doesn't tighten the threads have stripped in the hub

 

[SrC]

Not sure if this helps, but knock on wood I have not had any issues with my slipper since. The last time I had issues, I replaced a seized bearing and pads, I put some loctite on the screw before putting the slipper assembly back together. I then did the "drag" method of tightening up the slipper. I double check the tightness before each run to make sure.
Be sure to inspect your assembly for cracks in the metal hubs as well as "burnt" pads.

Blue TL for sure, just make sure not too much that slops all over. After adjusting it, don't run it. Just Let the TL cure for the better part of a day.

 

[dqb]

On my Vorteks there was a big gap in the power module that allowed a lot of sand and grit in, destroying both metal pinion and plastic spur gear. When you replace, it’s wise to seal this up somehow (grease, loop side of adhesive Velcro, foam, etc) and it will make it last a lot longer. Also metal spur gear is recommended. If you buy the parts separate and assemble yourself it works out to about the same $ as a fully assembled slipper with plastic spur.

 

[305HemiGuy]

After taking @Velodromed 's advice I opened up the power module and sure enough the spur gear is stripped. @dqb mentioned a gap that allowed a lot of dirt and debris in his rig, I found that area in my Senton also had a lot of accumulated debris and dirt there (I Cleaned it out some prior to taking picture). I guess the next step is to order a steel spur gear and go from there I wonder why Arrma decided to leave that space at the bottom and leave the spur gear exposed/open, seems like a bad design IMO.

 

[Surchaufeur]

Best thing is to cut a Slot in the chassis under the spur

 

[Velodromed]

After taking @Velodromed 's advice I opened up the power module and sure enough the spur gear is stripped. @dqb mentioned a gap that allowed a lot of dirt and debris in his rig, I found that area in my Senton also had a lot of accumulated debris and dirt there (I Cleaned it out some prior to taking picture). I guess the next step is to order a steel spur gear and go from there I wonder why Arrma decided to leave that space at the bottom and leave the spur gear exposed/open, seems like a bad design IMO.

View attachment 226067

View attachment 226068

I put a strip of soft Velcro across the bottem and cut out the space to expose the spur. That keeps out 70% of the crud. I’m also in the habit of opening up the power module and inspecting/cleaning every 4-five packs. It is not uncommon for the motor mount to shift slightly which can then lead to stripping the spur. Or the motor mount can bend slightly with the same result. And of course all the crap that builds up inside is not good. I also put a O-ring (with o-ring grease) and a washer on top of it under the pinion to help keep fine dust from getting into the motor bearing and use small pieces of electrical tape to cover the motor mount holes that aren’t being used.

On my two most used (and jumped) 3S cars I put in the 75 dollar M2C motor mount/brace. It keeps out 95% of the crud. I love it. I rarely have to open up and check those motor modules. I still do every 10-12 packs or so to make sure the motor hasn’t shifted. There’s hardly any crud inside when I do.

You can easily drop in a steel spur. Don’t forget you need an extra pad for it. But the plastic spur will last a long time if you watch over it and care for it. I have only stripped 2 over the last two years between four, 3S cars and I beat the crud out of them. Looking at your picture, you definitely need to clean more often regardless of whether you put in a steel spur or stick with plastic. It also looks like the motor may have shifted slightly in the mount, starting the strip process. You can ruin a steel spur gear as well by not paying intention to it.

Whenever I open the power module to clean I double check and often replace the motor mount screws. I like to use 243 locktite and I do not use motor mount cap heads more than once. Once removed I toss them into my misc screw box to reuse on less stressful applications. I like 12.9 tool steel cap heads. Same with pinion grub screws, Except I threw those away once I’m done. I like 5 mm long, flat tip grub screws. I’ve never stripped one of those out and the flat tip holds the pinion to the motor shaft extremely well.

 

[AIan]

I believe some people also cut the chassis under the spur gear where the indent is in the chassis under the power module to let stuff fall out, but I don’t know how well it works or if at all.

 

[Hector_Fisher]

I believe some people also cut the chassis under the spur gear where the indent is in the chassis under the power module to let stuff fall out, but I don’t know how well it works or if at all.

+1 I've done this. It actually does help.

 

[foobar]

hi there,
just grease your casing to seal the space between the cassis:

This works perfect. I use this for 6 months now and i bashed my senton a lot. I opened the power module only for maintenance two times so far. There was no single crumb of dirt. My spur gear still looks like the first day

 

[305HemiGuy]

Thanks for all the advice guys, I greatly appreciate it. I'm going to try the grease method. Seems like it yields pretty good results.

 

[Velodromed]

Thanks for all the advice guys, I greatly appreciate it. I'm going to try the grease method. Seems like it yields pretty good results.

Just remember that won’t help with the plastic ‘motor bearing killer’ dust that results from the metal pinion on the plastic spur. Regardless of the method used it’s still smart to open it up, check the mesh, mount and clean often.

 

[Pat_ranch]

Keep the slipper hub parts and make a spool with a trashass spur (38t iirc). Then grab a firma 150 from jenny's, put a 26t pinion on it, and you'll have a 60mph+ senton on 4s, and maybe 90mph on 6s
What could possibly go wrong?