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Hi all - I have a new-to-me 480 Gold which is in marginal shape but I didn’t mind cosmetics too much as was going to use in a vintage, light-duty, occasional runner.

Problem is the mounting holes on the can are stripped - including one from each pair (!) so it can’t be mounted securely

Anyone have a workable solution? Doesn’t have to be perfect…

I don’t want to tap for a larger screw as would have to enlarge the motor mounting plate holes (happens to be going on an Ultima presently).

I’m tempted to try a little something inserted into the hole (like a very thin metal sleeve). Possibly alum foil or Teflon tape or something similar wrapped around the mounting screw? Just enough to give some interference so it can hold decently… but not something that could tear up the motor if it came loose.

Just discovered this tonight. Any suggestions appreciated!

Another motor or tap to M4.

morrisey0 wrote: ↑Tue Apr 19, 2022 9:20 pm Another motor or tap to M4.

Hi thanks - I maybe wasn’t clear above but can’t use an M4 without modifying the Ultima so don’t want to go that route. I could use another motor but wanted to run that Le Mans on the Ultima - I have another nice 480 gold in my collection to keep safe. This one was to run without regrets! I had one a long time ago so look forward to running one again

Anyway found some additional suggestions I might try in this thread - it was for Nylon repair but ideas might still work. I’m considering the Teflon tape, thread locker (maybe red), CA glue and an insert/helicoil. The threads are still somewhat there so a small fix may be enough.

https://www.rc10talk.com/viewtopic.php?f=38&t=33916

Fine M3 threads are .035 pitch, and I don't think there are any heli coil kits out there for that. You could try a course .05 coil, but the body of the motor doesn't have much to grab on to, so not sure if that is a viable option, but such things are available.

If the fine threads are stripped in the motor, then you basically have 3m holes. I don't think any kind of "filler" like tape, foil, or loctite (do you really want to bring red loctite near a RC car?) is going to do you much good. If there isn't anything there to grab on to, there isn't anything there to grab on to.

If you don't want to hurt the car, then just grab a $20 reedy and run it while waiting / looking for the perfect motor for it. Trying to rig a stripped out motor doesn't seem worth the hassle or possible damage to me.

M3 Helicoil. Install the coil with Locktite.

....We have a forum member that can turn a Trinity into a LeMan's (and looked really good). Ever considered running a counterfeit LeMans? Or even just the can from another motor?

Wood screws. No joke. I was poor and known to strip a lot of motor mounting holes.

I'd try a thread insert , they are designed to be used as metal thread inserts for plastic parts ,I have some in M3 , you stick them onto the tip of a soldering iron and push them into a plastic hole meeting them into place , they are knurled on the out side to grip , I think if you drilled out the thread to just the right size hole you could press one into the ally . Alternatively try glueing an M3 nut on the inside of the can

juicedcoupe wrote: ↑Tue Apr 19, 2022 10:15 pm M3 Helicoil. Install the coil with Locktite.

Seriously.

https://www.amazon.com/Threaded-Inserts-Stainless-Helicoil-Installation/dp/B07QWBS1VM/ref=pd_rhf_ee_s_rp_c_sccl_33/139-5920935-2826369?pd_rd_w=gVfSq&pf_rd_p=961484e4-9800-4359-8d69-ee5560f2fd47&pf_rd_r=0WHD1PVCXV84TP8NHXDR&pd_rd_r=73d5e003-2e14-4d29-9370-c0cfe4ea931f&pd_rd_wg=iR22A&pd_rd_i=B07QWBS1VM&th=1

This type of repair is literally what they are made for.

They are a little expensive for a one time use but it probably isn't the last M3 thread that you'll ever strip.

juicedcoupe wrote: ↑Wed Apr 20, 2022 4:15 am

juicedcoupe wrote: ↑Tue Apr 19, 2022 10:15 pm M3 Helicoil. Install the coil with Locktite.

Seriously.

https://www.amazon.com/Threaded-Inserts-Stainless-Helicoil-Installation/dp/B07QWBS1VM/ref=pd_rhf_ee_s_rp_c_sccl_33/139-5920935-2826369?pd_rd_w=gVfSq&pf_rd_p=961484e4-9800-4359-8d69-ee5560f2fd47&pf_rd_r=0WHD1PVCXV84TP8NHXDR&pd_rd_r=73d5e003-2e14-4d29-9370-c0cfe4ea931f&pd_rd_wg=iR22A&pd_rd_i=B07QWBS1VM&th=1

This type of repair is literally what they are made for.

They are a little expensive for a one time use but it probably isn't the last M3 thread that you'll ever strip.

Thank you for this. I was reading more about them and am quite encouraged this could work if I want to truly repair the can.

I’m uncertain about 0.5 vs 0.36 thread pitch as mentioned above but if’s a standard M3 seems it should work…?

Need to do more research. an M3 kit would be good to have in the tool kit.

THEYTOOKMYTHUMB wrote: ↑Tue Apr 19, 2022 10:49 pm Wood screws. No joke. I was poor and known to strip a lot of motor mounting holes.

I’ll look into this. It’s coarse (sorry couldn’t resist the admittedly very very bad pun) but could work here.

Dadio wrote: ↑Wed Apr 20, 2022 3:22 am Alternatively try glueing an M3 nut on the inside of the can

will have to think about this as another option. As long as I get it secured so there acceptably low risk of it coming loose inside the can and I check it periodically to make sure it’s tight. Maybe locktite would be enough. I don’t want to destroy an armature though.

Frankentruck wrote: ↑Tue Apr 19, 2022 10:21 pm ....We have a forum member that can turn a Trinity into a LeMan's (and looked really good). Ever considered running a counterfeit LeMans? Or even just the can from another motor?

Yes would consider this too. I’m sure I’m being stubborn but want to make as few changes as possible to the existing motor at this point.

b027 wrote: ↑Wed Apr 20, 2022 7:24 am

Dadio wrote: ↑Wed Apr 20, 2022 3:22 am Alternatively try glueing an M3 nut on the inside of the can

will have to think about this as another option. As long as I get it secured so there acceptably low risk of it coming loose inside the can and I check it periodically to make sure it’s tight. Maybe locktite would be enough. I don’t want to destroy an armature though.

Just had another thought that may work best in short term - if I put an M3 screw through from the inside the motor coming through the face plate and locktite in place it should be stable and not loosen up on its own. Then I can feed the screw and motor through the chassis mounting plate and secure it with nuts on the outside. Could use two nuts to lock them together.

I’m still going to look into the helicoil kits for a longer term fix (or maybe just a better motor/can), but I’m guessing this will work well enough for now!

Thanks for all the great suggestions! This place rocks

b027 wrote: ↑Wed Apr 20, 2022 7:24 am

juicedcoupe wrote: ↑Wed Apr 20, 2022 4:15 am

juicedcoupe wrote: ↑Tue Apr 19, 2022 10:15 pm M3 Helicoil. Install the coil with Locktite.

Seriously.

https://www.amazon.com/Threaded-Inserts-Stainless-Helicoil-Installation/dp/B07QWBS1VM/ref=pd_rhf_ee_s_rp_c_sccl_33/139-5920935-2826369?pd_rd_w=gVfSq&pf_rd_p=961484e4-9800-4359-8d69-ee5560f2fd47&pf_rd_r=0WHD1PVCXV84TP8NHXDR&pd_rd_r=73d5e003-2e14-4d29-9370-c0cfe4ea931f&pd_rd_wg=iR22A&pd_rd_i=B07QWBS1VM&th=1

This type of repair is literally what they are made for.

They are a little expensive for a one time use but it probably isn't the last M3 thread that you'll ever strip.

Thank you for this. I was reading more about them and am quite encouraged this could work if I want to truly repair the can.

I’m uncertain about 0.5 vs 0.36 thread pitch as mentioned above but if’s a standard M3 seems it should work…?

Need to do more research. an M3 kit would be good to have in the tool kit.

M3X0.5 is the common size.

I have that exact kit. After slightly modifying the tool, it works fine.

Helicoil is best. It's a tiny repair though so care is needed.

Alternately, do as you mentioned, run a screw from inside and turn it into a stud/nut arrangement. A single nut is fine, along with a washer.

juicedcoupe wrote: ↑Wed Apr 20, 2022 8:30 am
M3X0.5 is the common size.

I have that exact kit. After slightly modifying the tool, it works fine.

Thanks! Could you elaborate on the tool modification?

I haven’t done a helicoil before but have seen a couple videos so have a basic understanding at this point.