Lastek 40 E

Pore free welding of dirty cast iron

Nickel cored electrode with a special coating for welding grey and malleable cast iron. It has a “pulsating” way of welding. There is alternately a phase where the arc only creates “heat” without deposit (oil and grease are burned out of the base metal during forward motion) and a phase (backwards motion) where a droplet on the cast iron is projected. In this last phase, the slag is pushed backwards and a very large area around the molten pool stays visible, permitting easy control of porosity on contaminated or oil soaked cast iron. Due to the pulsating properties (controlled heat input) and the possibility to use the negative pole for the first pass (slower cooling rate and thus less hardening of the heat affected zone), a soft, machinable and dense deposit without undercutting is easily obtained.

Specifications & Usage


Recommended for welding cast iron that has to be leak-tight and machinable, such as cracked motor blocks, pump housings, gear wheels, rebuilding the bed of a lathe, valve seats.

Hardness: 130 - 160 HB


For the first pass on cast iron, Lastek 40E is welded on the negative pole with a weaving technique(weaving forwards and backwards in the direction of travel)

Following passes can be welded on the positive pole to increase travel speed.

Peen the deposit after every pass to reduce stress build-up.


Welding proces: Covered electrode (SMAW)
Material Type: Cast iron
Welding positions: All
Norm : EN ISO 1071
Classification: E C Ni-CI 1
Norm: AWS A5.15
Classification: E Ni-CI
Minimum packing: 5 kg in a plastic box