No hijacking
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No hijacking
After looking at the photo of the inside of the breechblock I can see no reason why the entire rear face that has cracked out cannot be built up with weld and remachined to increase the rear face by 1.5mm (.060"), rebore the pivot hole, anneal then re-case harden the entire hammer. If you get binding from the mainspring at full cock, then a small radius could be filed (before hardening) at the junction of the two faces to bring back that small area to the original dimension. You would need to do a sketch with accurate dimensions first so you can accurately position the new pivot hole.
That's pretty well what Mr Vulcan and I came up with in the weekendQuote:
Originally Posted by gundoc
Now I need to sit down with my welding guru and see how he would approach it
What's not so obvious it it's a surprisingly small hammer with a small diameter pivot screw
With a very powerful main spring that has quite a static weight
I guess that's why the Ballards were legendary target rifles
Ha! Great minds etc.:thumbsup:
A pump repair I had to do a while back looked something like that - couple of pins cracked and flogged out which prevented the parts engaging correctly and the end result was a timing issue that locked the thing up. Different machine but similar fault be the looks of it.
The repair was to pin the part down hard, put a mill through the pin bores and sleeve the holes to the correct dimension with a polished hardened sleeve. The edges of the carrier plate were carefully welded up by a tig maestro with something tough as a filler, with heat control measures taken to not alter the hardened gear forming the center of the carrier. Then after the carrier was welded, the holes were machined out using a bloody expensive cobalt mill and the sleeves were pressed in with never move (tm) retaining poo. The sleeves were about an inch wide (bloody thing was all imperial) and once in place the sleeves were ground down to the required thickness - ground once in place made them a lot easier to hang onto and the assembly acted as the heat sink for the sleeves... Worked, and meant that the pump was out of service for a couple of days or so rather than several weeks while the 'correct' part was made wherever the thing came from.
I hate bores with thin walls on one side - it's always a place of failure and always ends up swelling out at a crack where it's thinnest which takes everything out of alignment. We can do better with design by just not removing so much meat around pins!
i would weld it and re heat treat like gundoc said
I got a bit side tracked by life and this project stalled
Well I decided to make a new hammer so no harm in firing it with the existing original that's faulty
Can't make it much worse and nice to finally fling some lead from a rifle that's been in collections for many decades
Shooting a known to be under size bullet the group is ok
It did loosen and lot of historic lead fouling that a lot of cleaning by me had not freed
So I need to cast and powder coat a better size bullet and test again
Attachment 214493
I had just fitted a newly made 4340 lever pivot screw
The original was worn and slightly bent
The new one is hardened and tempered and very closely fitting and has dramatically tightened the action without any other pins or links needing to be done
The problem with your hammer is that some dick head has tried to open the action lever while the hammer was on full cock, this breaks the web at the back and elongates the hole.
The fix is fairly simple, as there is plenty of meat above, below and in front of the break use a hardwood dowel in the top curve and a brass plate behind the full cock notch and squeeze it back together in a good metal vice, it will rebound a little bit ( could tig it if you wanted to ) this will let the half and full cock engage ok and be perfectly safe it wont pull apart again.
I have done this myself and it works, I used a metal bolt on top which left a slight mark on the hammer curve, so I suggest a good hard wood dowel.
Welcome aboard @George75Quote:
Originally Posted by George75
You sound like a man who knows his way around a Marlin Ballard
Cheers
I'm No expert, I do have a few I've worked on ( can only afford the cheapies) another tip for you is , if the lever droops a little after your lever and link and screw repairs , is to carefully peen downwards the back rear of both breach block halves ( not much) where they connect on the frame, don't over do it.
This will let the lever close tight with a nice sharp snap .
@George75 the lock up is nice and tight and no lever droopQuote:
Originally Posted by George75
The new lever 4340 lever pivot screw sorted multiple small problems
And the links and pins were all just fine
So I will strip the breech block tomorrow and look at that technique you described earlier
post some more photos please this is bloody interesting
Wel I implemented the solution given by @George75
I turned a 7075 alloy rod to match the hammer curve
Put it all in the vice with a 3mm alloy shim to protect the trigger notch
Closed the gap easily with very little spring back
When in CHCH next I will get some laser welding done across the crack
The pivot screw now has very little play and I expect this will be perfect for my needs
It's never going to be a high volume shooter
But nice to do a good fix that keeps it as original as possible
Attachment 215964
looks good laser welding is bloody interesting to
