Best glue to fix broken stud

If it is MTH, they make a stud repair kit.  I don't have the part#

I repair those with JB-Weld.  If the post is split, I will encase it in a piece of appropriately sized brass tubing and then fill it with JB-Weld, and also secure it to the shell.  Drill a new hole, and it's stronger than new.

gunrunnerjohn posted:

I repair those with JB-Weld.  If the post is split, I will encase it in a piece of appropriately sized brass tubing and then fill it with JB-Weld, and also secure it to the shell.  Drill a new hole, and it's stronger than new.

John is right. I'll add I use solvent glue to attach the stud.....then fill around it with JB  or a good 5 minute epoxy. 

Plus 1.  The brass tube will prevent future splitting.  Very common.

A true stud is never broken.   

Thirded or fourthed.  In extreme cases, I may drill out the hole and put in a piece of music wire or brass rod, then JB Weld. 

Mitch 

gunrunnerjohn posted:

I repair those with JB-Weld.  If the post is split, I will encase it in a piece of appropriately sized brass tubing and then fill it with JB-Weld, and also secure it to the shell.  Drill a new hole, and it's stronger than new.

X 2 for the technique using  JB Weld just remember that it requires a 24 hr cure period before reaching maximum strength.  JB also makes a 5 minute epoxy but IMO, the standard JB is stronger.

It's not just your opinion Dennis, they actually state that on the specifications for the JB-Kwik vs JB-Weld.   I confess, I frequently use the JB-Kwik anyway, it's plenty strong for the job, and I can complete the repair on the spot.

gunrunnerjohn posted:

It's not just your opinion Dennis, they actually state that on the specifications for the JB-Kwik vs JB-Weld.   I confess, I frequently use the JB-Kwik anyway, it's plenty strong for the job, and I can complete the repair on the spot.

Agree......plenty strong for fixing toy trains......but I like to 'overkill' when fixing things!

AMCDave:

"I'll add I use solvent glue to attach the stud"

Yes. The best "glue" to use on any plastic repair is a solvent - that is, regular plastic cement, like Testors. Certainly it has to be the right glue for the right plastic, but most of our plastic stuff is styrene and its cousins, so Testors (etc) does the job. It's not really a "glue" (CA is a glue, or adhesive) - it actually melts the plastic back into one piece. Better than CA - for this.

To the point:

I also use CA and epoxy and brass tubes and such - all good - when making repairs, if needed, but "re-merging" the material is always the strongest start.  

(Much of the above does not apply to most plastic RR trucks material (acetal) - who knows how to fix that stuff.)

 I've filled brass tube with solder, drilled and set a self tapper in it.

I usually just use straws and cut the straw off later if needed.  I usually use JB regular for posts to ensure enough work time for "drizzling" the straw full of JB Weld. Extra coarse grooves/sanding in the plastic helps the bond just like toe nailing nails does with lumber. Adhering to plastic varies by item. It isn't even a brand or color issue. I have Lionel  JBW repairs that are perfect and others that it cant stick well to at all.