Amateur hour with NMO hole saw and 2016 Silverado

[guttapercha]

I had finally gotten up the courage. I had my checklist:

1) Laird HS34
2) Blue tape, tools and such
3) Compressed air to blow away metal filings
4) Safety glasses
5) Comtelco 3/4" NMO assembly

I measured..measured again.. and measured again.

I proceeded to drill. It worked! There was a little nubbin of metal at the bottom of the hole that could have used some deburring, but the mount seated just fine, as I was able to check the base through the dome light.

Two problems:

1) Chipped 2 teeth of the HS34 on the first use.


2) Took 2 hrs to get the seatbelt guide assembly back onto the B pillar. Here's a helpful hint for others using the B-pillar on this vehicle: The assembly might not come out in one piece and will separate into two layers of seatbelt guidance plus the outer piece. Make sure to grasp the outer piece plus the one directly underneath before pulling to get the clip out of the body.

Unfortunately I have one more hole to drill and using the saw with the missing teeth on a vehicle seems risky.

To be continued..

[clbsquared]

How fast were you drilling? Take it slow. Don't force it. Let the bit do the work. I have that same hole saw and it has done close to a hundred holes.

Sent from my HTC One A9 using Tapatalk

[guttapercha]

Originally Posted by clbsquared

How fast were you drilling? Take it slow. Don't force it. Let the bit do the work. I have that same hole saw and it has done close to a hundred holes.

Sent from my HTC One A9 using Tapatalk

I was going for about 6 revolutions per second (the instructions stated 460 rpm max) but definitely possible that I got anxious and sped up.

[Mark]

A little cutting oil also should help...

[guttapercha]

Originally Posted by Mark

A little cutting oil also should help...

That would have been smart. Watched too many youtubes with no lubes (on people's hole saws, that is).

[jonwienke]

Not just smart, mandatory when cutting metal (except for a few cases using carbide tools to cut aluminum).

[Mark]

Originally Posted by guttapercha

That would have been smart. Watched too many youtubes with no lubes (on people's hole saws, that is).

Yeah done some work with hole saws 1" and larger at work on dry brittle stainless steel
1/16th and thicker.Slow speed and lots of cutting oil..Gets smoky buts saves bit for a while.
Even with that hole saw blades don't last long on stainless metal.. A few holes is most you get before they are done..

[guttapercha]

Originally Posted by Mark

Yeah done some work with hole saws 1" and larger at work on dry brittle stainless steel
1/16th and thicker.Slow speed and lots of cutting oil..Gets smoky buts saves bit for a while.
Even with that hole saw blades don't last long on stainless metal.. A few holes is most you get before they are done..

Sage advice. Thanks.

[FFPM571]

Originally Posted by jonwienke

Not just smart, mandatory when cutting metal (except for a few cases using carbide tools to cut aluminum).

I've drilled thousands of antenna holes in 20 years in the upfitting and 2 way business, never used cutting oil. Steady even pressure and an a constant speed. If you are missing a tooth or two its fine . That first tooth on the blade always seems to be the one that gets lost first.

[FFPM571]

Originally Posted by Mark

Yeah done some work with hole saws 1" and larger at work on dry brittle stainless steel
1/16th and thicker.Slow speed and lots of cutting oil..Gets smoky buts saves bit for a while.
Even with that hole saw blades don't last long on stainless metal.. A few holes is most you get before they are done..

Silverado roofs are not stainless steel

[jonwienke]

It's mandatory if you want to maximize cutting tool life, and also helps keep the cuts cleaner. A properly-lubricated cutting tool lasts longer, and chatters less. Particularly when cutting steel.

[Mark]

Originally Posted by FFPM571

Silverado roofs are not stainless steel

Wow..Really? didn't know that..LOL
Thousands eh? In the Chicago area bullet holes don't count.

[ka3aaa]

Green Lee whole punches work much better and are considerably faster than a hole saw.

[R8000]

Originally Posted by FFPM571

I've drilled thousands of antenna holes in 20 years in the upfitting and 2 way business, never used cutting oil. Steady even pressure and an a constant speed. If you are missing a tooth or two its fine . That first tooth on the blade always seems to be the one that gets lost first.

Same here. Been doing it for 13 years myself.

[Mark]

Originally Posted by ka3aaa

Green Lee whole punches work much better and are considerably faster than a hole saw.

Yeah Green Lee's are nice when you can get the space..
Electricians at work use them to punch conduit holes in their electrical box panels.
Great tool.

[FFPM571]

Originally Posted by jonwienke

It's mandatory if you want to maximize cutting tool life, and also helps keep the cuts cleaner. A properly-lubricated cutting tool lasts longer, and chatters less. Particularly when cutting steel.

Yea because using cutting oil on a hole being drilled in a roof so it can drip into the vehicle's headliner and stain.. Not needed when drilling a body panel that is less than 1/8 in thick...

[n9mxq]

First one is the worst one.. You learn a new trick each time..

[12dbsinad]

Thousands of NMO holes here as well, no oil either as I don't want to be responsible for telling the owner of a brand new 75,000 + vehicle why there is a large oil stain in the headliner. Blades last a long time if you proceed slow and let it do the work.

Eventually you'll need to replace it like any cutting tool, but should last forever if not drilling holes on a professional level, especially with the new aluminum bodies. You can pretty much spin the saw backwards and make a decent hole.

[n3obl]

I keep spare blades on hand. And you need a nice slow speed with not too much pressure. Drilled hundreds and only issue i ran into was not checking the underside when i drilled hole one time and found a hidden crossmember. Made a chore running the coax.

[prcguy]

Not in a sheet metal car roof.
prcguy

Originally Posted by ka3aaa

Green Lee whole punches work much better and are considerably faster than a hole saw.