Hi everyone, I'm getting closer and closer to doing the actual welding of a CM cage into my doorslammer.

Question on filler rod:

Should I use non-copper coated steel?

I have seen pics of welds under magnification where the copper looks to be floating above the pool and not really a part of the molten steel.
Thanx.

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Go NAPA/ Rockstar funny car team!

Use Er70s2.

Paul,

Torch here. Call my cell when you have a chance and I will give your
answer.

949.842.3657

See you,

Torch

is er80s-d2 the best for 4130?

Yes, with clairification:
Somewhere in recent history when Oxweld 65 seemed to go away, (ESAB nows owns the name) Triple-deoxified is the term that went with that brand. It seems that the "equivilent" charts refered to E-70S-2. The spec. now allows Single-deoxified, so many (mostly foreign) manufacturers are supplying rod that tends to weld "dirty".
ER80-D2 IS Triple-deoxified by spec. and will weld far cleaner.
Under NO circumstances do you believe most "Drivel" on internet welding sites about using stainless rod by some individuals, go with Lincoln or Miller information or anything supported by AWS, not somebody who's Uncle lives four doors down from a guy who knows ......... (insert famous name here)!

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Bob Meyer Race Cars / San Diego
2005 Our 40th Anniversary

Thanx gentlemen!

I'm having the damndest time making the joints for the tubes.
Quickly found out that a bi-carbide hole saw on an "ole joint jigger"
does not stand up to chrome moly tubing. Wiped the teeth out fast!

Where can I find one of those end mill drill bits that looks like the rotor in a screw blower? What size bit do I want? Tubing is 1 5/8" 4130 from aircraft spruce in Corona.

Would I be able to hold a hand held grinder and do them?

If you plan on doing a lot of chassis work, get one of these
http://www.mittlerbros.com/Tube_Notcher_Ultimate.htm

A little pricey but they are great to work with and well worth the initial investment!

They also sell the bits your looking for, atleast the ones that fit their machine. Use the same bit size as the OD size of the tubing your fitting to.

If you aren't going to do more than one car, stick it out with the notcher and hole saws(don't spin 'em too fast and keep plently of cutting oil handy). Just becareful when they get almost all the way through, they love to grab and try to turn your wrist directions it should never go. Or just whip out the grinder and do them by hand. That's the best way to learn anyways!

Your spinning the holesaws too fast, I've notched plenty of CM and the holesaws last me quite awhile, I put my joint jigger in a drill press and changed the pulleys to make it run really slow, use very little force on the quill feed, plus I use water soliable cutting oil. When using any kind of saw with teeth ther should be aleast three teeth on the material at all times, any less the teeth will hook then brake off, if the three teeth is not possible a real slow speed and light pressure will keep you from braking teeth off.

You are absolutely correct ! 200 rpm is about right. Use one finger on feed handle, so you don't have a lot of down pressure and if a tooth catches, you finger pops off without hurting the saw. Remember.... it is a SAW, not a punch!

__________________
Bob Meyer Race Cars / San Diego
2005 Our 40th Anniversary

Your drill press is running to fast. If your useing a hand drill then thats your problem. Hole saws on Jig a joints or other QUALITY fixtures and mounted on a drill press or Bridgeport running at slow speeds last a long while. Most people will say to use alot of WD40 or cutting oil while cutting the joint. PERSONALLY I don't like that because it promotes contamination of the welded joint. It can never get clean enough. Always seems 1 in 10 joints get contaminates when I use a lubricant of some kind. Maybe I'm just the dumb arss. I just go slow dry.