Aluminum pre-heat for welding

[Kuma]

OK, I know preheat is needed, how much? is there a temperature to pre-heat to, I can use an inferred temperature readout just need to know where to go.

[dogger315]

OK, I know preheat is needed,

Actually, it's not. Welding on these Aluminum frames is considered pretty
light duty and any decent TIG or MIG rig will get the job done without going
anywhere near it's duty cycle. If you are concerned about the tubing moving
around going from cold to hot and back, just keep everything clamped up
until it cools back to ambient.

If you still want to pre-heat, use a torch and your IR thermometer to get
the metal up around 400 degrees. Aluminum dissipates heat rapidly so I
recommend you only heat a small section, weld and then heat and weld
the next section as you go.

I welded this frame cold with a Lincoln Square Wave TIG 185. I even used
a pulser to keep the heat down. I didn't use a jig, I just kept the rails
clamped up until they cooled - no movement at all.





dogger

[Kuma]

Actually, this is for welding up a new swing arm for my quad project. The previous arm broke, one weld failed then the other side broke. The material could have been thicker but there was no pent ration with the weld.
So is that 400 F or C?

[dogger315]

400 F.

If you're still not getting good weld penetration, post up what type
of welding you're doing and your settings. Might just need to tweek
your settings.

Good luck with it.

dogger

[mxdogger]

I am preheating my welds on the downtube to the billet y i use, the material is thicker with both pieces. aluminum can look like it is welded and not have proper penetration, if in doubt pre-heat.

a trick i learned is to turn just your acetylene on, blacken the aluminum with it. now fire up your mix, heat the aluminum until you burn the black off. the aluminum should now be up to temp to weld. thicker material may need more, this is a good guage when you dont have temp gauge.

[Kuma]

Assuming Honda uses the same aluminum for all their castings what rod works the best? I'm grafting a TRX450R swing arm, rear section to a CR 250 swingarm casting, pivot section. this is for my hybrid quad.

[Kuma]

OK, forget I said it was for a quad
Does anyone have an answer?

[Wiley13]

OK, I know preheat is needed,

Actually, it's not. Welding on these Aluminum frames is considered pretty
light duty and any decent TIG or MIG rig will get the job done without going
anywhere near it's duty cycle. If you are concerned about the tubing moving
around going from cold to hot and back, just keep everything clamped up
until it cools back to ambient.

If you still want to pre-heat, use a torch and your IR thermometer to get
the metal up around 400 degrees. Aluminum dissipates heat rapidly so I
recommend you only heat a small section, weld and then heat and weld
the next section as you go.

I welded this frame cold with a Lincoln Square Wave TIG 185. I even used
a pulser to keep the heat down. I didn't use a jig, I just kept the rails
clamped up until they cooled - no movement at all.





dogger

What year is that frame? Did you reuse the stock Y?