Trailer Coupler Safety Pin Mod - drill out from 5/16" to 3'8" to fit a padlock???

   / Trailer Coupler Safety Pin Mod - drill out from 5/16" to 3'8" to fit a padlock??? #1  

hankross

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Trailer Coupler Safety Pin Mod - drill out from 5/16" to 3'8" to fit a padlock???

Maybe I'm missing something...I have always used a 5/16" safety pin to lock the coupler on my 6x16 landscape trailer but was looking for something a bit more secure and I am NOT a fan of the 1/4" coupler locks that are readily available. I would like to replace the pin with a padlock but the current hole (for the pin/lock) is too small. Primarily to keep honest people honest (don't want this to turn into a debate about the BEST coupler lock/protection).

No worries, I thought as I grabbed the drill and a selection of 3/8' drill bits. I tried all the drill bits I had (including some Cobalt types) and made virtually no progress. I drilled at slow speed and used cutting oil but still had no luck. Some questions for the group:

1. Is it a bad idea to drill out (assuming I can get a bit that will cut) the safety pin hole on the trailer coupler from 5/16" to 3/8"?
2. Is there a reason that you don't see padlocks installed as the safety 'pin' on the trailer coupler?
3. Is the coupler material typically a hardened steel? If so, please provide recommendations on drilling in a hardened material.

As always, thanks for your thoughts and welcome to alternative ideas. And yes, the drill bits are sharp! :)
 
   / Trailer Coupler Safety Pin Mod - drill out from 5/16" to 3'8" to fit a padlock??? #2  
Re: Trailer Coupler Safety Pin Mod - drill out from 5/16" to 3'8" to fit a padlock???

I use a padlock on mine. It has a 5/16 loop.

Or you can use the alternate method.

DuctTapeLatch.jpg

Bruce
 
   / Trailer Coupler Safety Pin Mod - drill out from 5/16" to 3'8" to fit a padlock??? #3  
Re: Trailer Coupler Safety Pin Mod - drill out from 5/16" to 3'8" to fit a padlock???

I tried drilling mine to enlarge the hole just a little. Same results as you.
 
   / Trailer Coupler Safety Pin Mod - drill out from 5/16" to 3'8" to fit a padlock??? #4  
Re: Trailer Coupler Safety Pin Mod - drill out from 5/16" to 3'8" to fit a padlock???

A carbide tapered rotary file will enlarge the hole,, no problem.

rotary-file-carbide-bur-Dumore-R877-0054.jpg
 

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   / Trailer Coupler Safety Pin Mod - drill out from 5/16" to 3'8" to fit a padlock???
  • Thread Starter
#5  
Re: Trailer Coupler Safety Pin Mod - drill out from 5/16" to 3'8" to fit a padlock???

CADPlans-
Thanks for the tip. I need to get one of those carbide tapered rotary files and get after it. I can already see other uses for the new tool. Sounds like they are typically used in a die grinder or similar tool - correct? Can you use them in a regular cordless drill or is very high speed recommended? Thanks again.
 
   / Trailer Coupler Safety Pin Mod - drill out from 5/16" to 3'8" to fit a padlock??? #6  
Re: Trailer Coupler Safety Pin Mod - drill out from 5/16" to 3'8" to fit a padlock???

All those pins do is keep the lever from popping up. It's not a security feature. Locks can be bypassed in seconds. Even BIG locks.
 
   / Trailer Coupler Safety Pin Mod - drill out from 5/16" to 3'8" to fit a padlock??? #7  
Re: Trailer Coupler Safety Pin Mod - drill out from 5/16" to 3'8" to fit a padlock???

CADPlans-
Can you use them in a regular cordless drill or is very high speed recommended? Thanks again.

I use mine in a cordless drill all the time.
 
   / Trailer Coupler Safety Pin Mod - drill out from 5/16" to 3'8" to fit a padlock??? #8  
Re: Trailer Coupler Safety Pin Mod - drill out from 5/16" to 3'8" to fit a padlock???

If I need to lock our trailers on the job site (construction company) I usually just carry a padlock that will fit it. Used to have a trailer lock somewhere and still do but don't know if I have keys anymore. If your needing to lock your trailer I would recommend just going and buying a proper trailer lock
 
   / Trailer Coupler Safety Pin Mod - drill out from 5/16" to 3'8" to fit a padlock??? #9  
Re: Trailer Coupler Safety Pin Mod - drill out from 5/16" to 3'8" to fit a padlock???

If I need to lock our trailers on the job site (construction company) I usually just carry a padlock that will fit it. Used to have a trailer lock somewhere and still do but don't know if I have keys anymore. If your needing to lock your trailer I would recommend just going and buying a proper trailer lock
Look underneath on many trailer couplers and you will see a big nut that can be loosened to adjust the coupler. Remove it and the lock on the handle of the coupler does you absolutely no good.

Aaron Z
 
   / Trailer Coupler Safety Pin Mod - drill out from 5/16" to 3'8" to fit a padlock??? #10  
Look underneath on many trailer couplers and you will see a big nut that can be loosened to adjust the coupler. Remove it and the lock on the handle of the coupler does you absolutely no good. Aaron Z
In about the time it takes you to kneel down to look I'll have the lock cut off with my cordless angle grinder.

image-3315404600.jpg
 

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