How to protect slot?

[kotlec]

Hello all

I am newbie welder. I need to close hole for rethreading in this stainless part. But how do I protect slot ? It is only 0.3 mm and I have no chance to clean it if stufed.

Any ideas ?

 

[Pete.]

Any ideas ?

Helicoil

 

[Gritineye]

AS above helicoil, or slide a bit of 0.3 brass sheet down in there, bit thin but might not blow through it if amps are low.

 

[kotlec]

Helicoil wont do in my case. Brass worth trying.

 

[Pete.]

Stainless can be the devil to do this kind of work on and if you stuff a 10 thou brass shim in that gap then weld against it you might never get it out again and that's if it doesnt melt which it's almost certain to do. What stops you using an insert?

 

[Agroshield]

Does the upstanding piece the other side of the slot also have a hole? If not, how will you re-drill and re-tap the thread if you weld up the hole?

Cut the projecting piece off at the bottom of the slot, V-prep the joint and weld a new piece back on.

0.3mm spacer in the joint to stop it closing up. May be better to tap the hole before welding back on.

 

[kotlec]

What stops you using an insert?

I can not touch hole on another side of slot wich can happen when I try to thread bigger diameter here.

 

[kotlec]

Does the upstanding piece the other side of the slot also have a hole? If not, how will you re-drill and re-tap the thread if you weld up the hole?

Cut the projecting piece off at the bottom of the slot, V-prep the joint and weld a new piece back on.

0.3mm spacer in the joint to stop it closing up. May be better to tap the hole before welding back on.

There is hole trough. Must be left untouched. Device is ultrasound cutter head. It is very delicate. Even slightest changes throw it off resonance. Big headache.

 

[Morrisman]

Make a brass plug that slides into the rear hole, with a shoulder on so it just passes the slot by a tiny amount. Then weld the hole up and you may get away with it.
Distortion from welding with probably be awkward.

 

[addjunkie]

How thick is a junior hacksaw blade?

 

[BrokenBiker]

There is hole trough. Must be left untouched. Device is ultrasound cutter head. It is very delicate. Even slightest changes throw it off resonance. Big headache.

i may be stating the obvious here, but would a new part not be the easiest and safest option?

how thick is the section to be welded? my concern with welding would be the distortion altering the tickness of the gap

 

[kotlec]

my concern with welding would be the distortion altering the tickness of the gap

That can possibly be biggest concern. Did not thought about that .
Looks like I'll be buying new part and saving time and effort.