Cylinder head material and weldability of DBD34 Cylinder head fins ?

[Stephen Foster]

Again ,
Hope this query isnt deemed offensive as relating to the single as opposed twin cylinder machine ?


I have a broken fin and one bent fin on the cylinder head of My "Gold Star" and before I set to welding them in place wonder if a knowledgeable member has any experience of welding these please ?

Im trying to find
1/ Material of cylinder head .
2/ welding rods or TIG repair of same .
3/Weld procedure which has been successful .
4/ pre-post heat used .

Thank You in advance,
Steve ..

[chaterlea25]

Hi Stephen,
I saw a facebook post last week from Seager engineering where he repaired fins on a DBD,

The experiences I have had getting BSAalloy bits welded up by my friend is that it welds well,
From memory,  (i hope to get him on the phone tomorrow to ask)
The rods are 4043
if the bent fin is not cracked? Try this,
Cover the area with black sharpie pen, heat until the sharpie ink has almost disappeared and leave to cool, this should have annealed the alloy fin enough to straighten it

John

[sean]

I have mig welded aluminum......, I pre heat to approx 150-200c every thing needs to be spotless no oil contamination, I have a dedicated stainless steel wire brush for cleaning , then go over everything with acetone , 4043 is the best wire for cast aluminum it flows better and has 5% silicon and I use 100% argon gas .....any tig welder with aluminum capabilities will work the same but with mig you need to push the wire as opposed to dragging .
good luck

[Stephen Foster]

I have mig welded aluminum......, I pre heat to approx 150-200c every thing needs to be spotless no oil contamination, I have a dedicated stainless steel wire brush for cleaning , then go over everything with acetone , 4043 is the best wire for cast aluminum it flows better and has 5% silicon and I use 100% argon gas .....any tig welder with aluminum capabilities will work the same but with mig you need to push the wire as opposed to dragging .
good luck

Thank You John ,
Will try that tip  .

[Stephen Foster]

I have mig welded aluminum......, I pre heat to approx 150-200c every thing needs to be spotless no oil contamination, I have a dedicated stainless steel wire brush for cleaning , then go over everything with acetone , 4043 is the best wire for cast aluminum it flows better and has 5% silicon and I use 100% argon gas .....any tig welder with aluminum capabilities will work the same but with mig you need to push the wire as opposed to dragging .
good luck

Appreciated Sean , I have an AC/DC TIG set so will be using that ..I had thought 4043 myself but wasnt sure of the head material ?

Thank You John ,
Will try that tip  .