Drilling into tubing

[Rutedog]

I need to dill 3 1 5/8 holes into a 2 1/4 16ga SS tubing. What would be the best way to drill these holes? I was thinking using a tubing notcher and a 1 5/8 hole saw, but most tubing notcher's only accept 2" tubing. I don't have a drill press, just a drill and these holes have to be perfectly aligned. This is for a log type manifold. Any help would be really appreciated.

[Richs]

Without at least a drill press using that hole saw it's gonna be tough. Especially since it's light gauge and stainless has a tendency to work harden. Hole saws will guide themselves once they get going but, they make a sloppy hole. That tube notcher would be nice if you could fit it, which you say it can't. What might be easiest is to trace out the hole you need (notch a piece of 1-5/8 tube with a 2-1/4 hole saw and use that to make your trace against the 2-1/4 tube) then drill a large pilot hole (unibits work exremely well) and finish up with a carbide burr out to the trace line.

[hankj]

I can't see any way to do that by hand and get the hole dead square with the tube. I'd hire it out.

Hank

[Richs]

the manifold gonna be for? Just curious...

[Masher Mfg]

Hole saws generally bore a hole 1 size larger then the marked size so a 1 1/2 cutter would be better.

If the holes are 90* to the tube a notcher won't help. Clamp it into a drill press and go from there.

Or send it to a machine shop, this isn't much of a problem on a vert mill. Make sure you give them accurate measurements otherwise you will end up with a wrong part built to your drawing. Sending a gasket and flange for checking would be a good idea too. Tell them it is for a exhaust manifold and discuss the tollerences. Stating the holes must be exactly 1 5/8 (1.625 ) and having the part come back 1.625 + - .0001 will cost you much more $ for no gain.

[Rutedog]

I think I'll be getting me a drill press .

Richs,
It for a turbo project. Going to boost a non-aspirated car.

Thanks for the feedback guys.

[Masher Mfg]

Some sort of V6? Or puting a turbo on a Sprint 3 cyl?

[Rutedog]

Masher,
I'll make sure to get a 1 1/2 cutter instead of the 1 5/8. Thanks for the heads up.

[Rutedog]

V6 3800 Series II

[MAC702]

It for a turbo project. Going to boost a non-aspirated car.

Does it have warp drive? Or did you mean naturally aspirated?

[Rutedog]

OOOPS!
Yeah, I meant naturally aspirated.

[hankj]

Hole saws generally bore a hole 1 size larger then the marked size so a 1 1/2 cutter would be better.

My Lenox hole saw kit cuts a hole the same size as the OD of the cutter. When you say "one size", do you mean by the sixteenth, or what?

Hank

[blueoval557]

Hank, Ive heard you always buy the size down from whatever size you really want, as they are never perfectly true and spind out of round sometimes. Ive always interpreted it as whatever the next size down is on the shelf...thats what you buy. Im with you though...Ive always drilled the hole with the exact size I needed...but I have heard this elsewhere as well.
Kyle

[Rutedog]

I'll pick up both sizes. I'll start with a 1 1/2 and see how that goes.

Off Topic

BlueOval,
I was in Sacramento last weekend and the heat you have to put up with is insane. I think it was 109 and I was there for an outside wedding .

[hankj]

OK.

I went out and grabbed a 1-3/8" unsused Lenox hole saw. Measured with a dial caliper, it reads 1.380 on the outside of the tooth cast. That seems like 1-3/8" to me. A "size" (32nd? 16th? 8th") either way would seem to be a big mistake in labeling. I never cut door hardware in 37 years with an under or oversized hole saw. If it's a 2-1/4" hole, I used a 2-1/4" hole saw!

Lo siento mucho, y buenos noches.

Hank