Rod clamp stud thread size

[Jason Groombridge]

G'day All,

I am just servicing a Penn Inter 50TW and both the rod clamp studs are broken off in the frame. Not enough sticking out to grab hold of so I drilled them out and tried the ezi-out. No joy. Drilled further and then tried to pick the brass bits out. Still no joy, the brass is just so corroded in there that I can't get it out. Next step is to tap but I don't know the tap size. Anyone know what size thread is on the 34-50T rod clamp studs?

Cheers

Jason

[alantani]

move on up to 1/4-20 studs.  that will be your best bet. 

[Jason Groombridge]

G'day Alan,

Sounds good to me as I have a 1/4-20 tap. What would the part number for the larger studs be then?

Cheers

Jason

[Robert Janssen]

The studs on a 50TW are already 1/4" -20. But i suppose you noticed that already. (or do they step down a size upon entering the frame?)

But it might help you to drill smaller straight through the remaining stud and try using a suitable size allen wrench for torque, or a regular thread tap. IME they tend to get a better grip than EZ-Outs do, using the tap to drive the broken part straight through rather than back and out. It often helps to soak it with penetrating oil (anything really). Citric and phosphoric acids are great for brass corrosion; oxalic acid too.

For new studs you could get away with using stainless all-thread rod.

.

[Tightlines667]

Not fun.  I have had to do this on a number of ocassions.  If you do have to step up one size, make sure you have access to a drill press, in order to make sure everything is centered and square.  Thankfully you don't have to drill the hardened SS reel seat on these.

Best of luck.

[Jason Groombridge]

G'day Guys,

Yep I went ahead and tapped it 1/4-20, which matched up with some studs off an old Senator I have so I suspected it was right.

The bits of left over brass were so corroded in there that I had to pick them out AFTER re-tapping the holes. There was a fair bit of corrosion in there which means that the threads are quite loose unfortunately. Hopefully it will still work OK. If not I'll get the reel back, drill and tap for M8 then get some M8 stainless bolts, trim the head down in the lathe and then centre drill and tap them 1/4-20 so they can accept the standard stud.

Thanks for your help, much appreciated.

Cheers

Jason

[Tightlines667]

You can add a strong metal bonding agent to the studs to help secure them, or you have to reap with a larger size, or use helicoio inserts.