Cracked Headtube Repair?

[MSYT]

Hey folks

I see there’s been lots of threads asking for new frames or warning others to check for a cracked headtube but I can’t seem to find one about a repair… if that’s even possible.

See, I’ve just picked up a Planet X Jack Flash. When it arrived it had a funny stain on the head tube so I cleaned it off and found a small crack. The seller didn’t notice and has offered me a refund and said to keep the frame but I would really like to use this bike.

I know it’s a dangerous spot. Right on the front. If left it could suddenly and dramatically cause me to lose some teeth… and more. Are there any options out there that have worked as a repair though?

The frame is 7005 aluminium if the grade makes any difference.

Reckon it would be possible to weld up the crack and then reinforce with extra material on the outside?

Or any recommendations for repairers?

Cheers
Mark

 

[novocaine]

It's heat treated any weld will destroy that in the area and make it soft. It will also need reaming round again afterwards and a headset may be sloppy in the hole afterwards.
Any good TIG welder should be able to V it out and lay in a new bead but I'd still be worried about it given its location and the abuse the frame is designed to take normally. If I was using it afterwards I'd want to use a deep cup headset like a Chris King or An achos.

 

[legrandefromage]

@danson67

 

[gtturbo]

As above Danson67 is your man. He has just done this one for me.

 

[ishaw]

In addition to welding the crack, you could have it sleeved for extra strength.

 

[MSYT]

It's heat treated any weld will destroy that in the area and make it soft. It will also need reaming round again afterwards and a headset may be sloppy in the hole afterwards.
Any good TIG welder should be able to V it out and lay in a new bead but I'd still be worried about it given its location and the abuse the frame is designed to take normally. If I was using it afterwards I'd want to use a deep cup headset like a Chris King or An achos.

I've looked in to 7005 a little and it looks like it isn't necessary to heat treat 7005, unlike 6061. Reynolds say:

Industry standard 7005 using zinc and magnesium alloying elements to provide strong, light frames. We recommend that frames are aged after welding to the T6 condition to achieve optimum properties. Unlike 6061, this alloy does age-harden over time, reducing the need for a full frame heat-treatment.

So... it may not have gone through a specific heat treatment.... which is a plus I guess

 

[MSYT]

As above Danson67 is your man. He has just done this one for me.


View attachment 771546View attachment 771547

Looks grand! I'll fire them a message

 

[MuchAlohaNui]

His rates are very reasonable too.

 

[Retro Spud]

Dan

Sorted my cracked Manitou out for me and did a corking job
See link in signature below