Aluminum Cylinder Head

[Ed in Ga]

My reason for buying a tig welder was use in rebuilding older motorcycles, mostly Brit bikes. The heads are sand cast aluminum and I understand the need to seriously clean the head issues. To attempt to build up an area for machining a new valve seat location what would be the amperage requirements? With preheat is 185 amps enough or is more required?
Ed

[Jerry]

Your not talking about that thick of aluminum, so yes with a pre heat I would think your find with a 180. I have welded many of these, I pre heat and I have a miller syncrowave 250, yet its not at all turned up.

I recently bought the tig torch stubby set-up parts for my weldcraft torch. I'm sure you know it can be a bear getting into those cylinders otherwise.

Good luck

[Ed in Ga]

Jerry,
Thanks for the reply. What rod do you use 4043 or 5356?
Saw a small torch somewhere that I think was made by weldcraft you could get into the space of a nickle, but it required water cooling.
Ed

[Jerry]

Both my tig machines are setup with water cooled torches and this is a must for welding aluminum, for the heat is much more then steel. I've used both types and I'm not really sure which I'm better off with right now. I'll have to pay better attention , but you know is it cleaned well is there any moisture or crap that is contaminating weld , sometimes hard to tell.

[Scott V]

Ed,lower your frequency down around 25/30,and try it on some thick aluminum.Watch how easy the puddle gets wetYou will not need a water-cooled torch with your setup,because of the true squarewave output.Your duty-cycle will kick in probably before your torch gets hot.I use a air-cooled torch on my 300 gtsw.

[Ed in Ga]

Thanks guys. I'll scrounge up a ruined head to play with. Read on another site to boil the head or casing in water until oil stopped coming to the surface to clean. Might be worth a try.
Ed

[Jerry]

I not sure I agree with you Scott, when duty cycle kicks in is to vent heat from machine but not the torch. Welding of aluminum takes more heat than steel because of the heat transfer with alum. Have you welded aluminum with your setup and if so what thicknesses. I know a person could stop and wait for torch to cool down if it becomes hot, which I think it will but when waiting no money is being made.

[Scott V]

Jerry, you have to try a real ac/dc inverter to see what I am talking about.the air-cooled torches do fine for most things,but not for production work at hi amps.If you tried a air-cooled torch on a Miller 180 at full output,you could not hold the torch for very long.If you did the same with a Thermal-arc 185 the torch would barely get warm.Thats why I said the duty -cycle will probally kick in first.I have had two watercooled setups one on my Esab 252,ac/dc(315 amp),and one on my Thermal 300 inverter.Also the puddle get wet way faster with lower amps with a inverter.You don't have to full throttle the inverter like a transformer machine.The whole setup is way beyond any transformer machine on ac it's not funny,but you can do great work with either one.It's just easier all around with the inverter.as far as thickness you could weld .250 aluminum very easy with a air-cooled 185 Thermal-arc.I use my power mig 300 for thick stuff.

[Jerry]

OK I do have one inverter welder which is my Pow Con tig welder and I do have a Bernard water cooler on it for when I weld it does get hot and then I'll turn it on for a while and then back off but this machine is only DC unit.

I have to ask how many welders do you have, it seems to me I've heard you talk about quite a few different ones. Are you self employed Scott or a dealership which Rocky states.

I have been hearing more about Thermal Arc welders. How long have they been around.
( Hey the Pow Cons fixed ) Going to auction tommorrow hope to buy some stuff Mill, Lathe, iron worker, welder, welder whatever.

Just bought Lincoln generator and tried it out, seems ok it just has to weld a couple of parts together once in a while and I'll be happy. Most my work is in shop.

[Scott V]

Jerry, lets just say I am not a welding dealership,It's just I went through a couple of welders looking for the right setup for me.I kind of got into welding from autobody work,and it has kind of expanded out into other type welding.That's kind of why I like my machines to weld down low very well.Right now I am kind of trapped in a heathcare issue as far as work.(caregiver)

[Ed in Ga]

Gentlemen,
I think Rocky's comment was made as a joke as Scott has gone through several welders in a recent period. Wish I got his deals.

Rebuildng motorcycles is a sure way to lose money no matter how much of the work you do yourself. Just my hobby or interest.
I mentioned the water cooled torch only because of its size.

Thermal Arc, Dyne or whatever seems to have been around at least since Miller bought Hobart.

Anyway, I'll find out when I get an old head.
Thanks for the help,
Ed