[Sin]

And if anyone knows his diff strokes, It would be Sin

But yes, Self tapping screws are the type of screw that have a "v" cut into the actual threads, Where as a self drilling screw has a smooth shanked tip with a "v" cut into it followed a 1/4" up the shank by threads. Self Tapping screws are used primarily for sheet metal, Whereas Self drilling screws are used where metals are thicker . Without a pilot hole and needing to be drilled thru prior to the addition of threads.

Self tapping screws will require a predrilled hole close to its size. On its first few turns, it will produce a thread pattern the rest of the screw can use till its tight.

Self drilling screws will work on metal that does Not have a hole predrilled and upon "drilling thru the metal" it will act as a self tapper above.

Plain Sheet metal screws require a hole to be drilled near the thread range for ease of instalation.

I know right about now, Sins probably saying "I put any ****er in the drill, and its going in" LOL

I'm just pointing out the differences in terms really to inform others out there, not nitpicking on what you use.

Altho I should add a disclaimer, "Any screw can be used for the wrong reason to get desired results" Sort of along the line of using a hairbrush to mix paint cause the bristles add more turbulance LOL Just pointing out the slight misconception lots of peeps had when I dealt with the hardware store for 20 years.

Plain sheet metal screws are great for the EPA caps if you predrill to the appropiate size.you aren't looking to thread them anyhow.

Dynojet kits do come with the drill bit and the sheet metal screw.

:::Waiting for the Arsenic "DJ sucks large farm animals" comment:::: LOL

alright i think that makes you me and maybe 5 other people on this site that actually know that much about screws and bolts

but yes you are correct and i probably know more about screws then most people really want to know since ive spent my whole working career as a machinist/welder/engineer

but it makes me happy to know someone else out there knows the diff now if that could teach the rest of America that SAE bolts have no business in this world anymore then ill be happy

[arsenic]

:::Waiting for the Arsenic "DJ sucks large farm animals" comment:::: LOL

Dynojet sucks large farm animals, there happy now?

[danp2630]

Dynojet sucks large farm animals, there happy now?

Man am I glad you said that! Finally!!!

[Newbie2it]

alright i think that makes you me and maybe 5 other people on this site that actually know that much about screws and bolts

but yes you are correct and i probably know more about screws then most people really want to know since ive spent my whole working career as a machinist/welder/engineer

but it makes me happy to know someone else out there knows the diff now if that could teach the rest of America that SAE bolts have no business in this world anymore then ill be happy

I agree on the S.A.E bolts, But people still look for them. I dont see that going away anytime soon unfortunately.

Dynojet sucks large farm animals, there happy now?

LOL I knew that was coming so I left the door open for ya Arsenic

[mharrison]

I got caps off pretty easily, I didn't end up using a drill stop, but carefully drilled into the cap until eventually, it wrapped itself up around the bit and pulled right out.

FYI, for a quick cheap drill stop, put a few rounds of masking tape on the drill bit. It won't stop someone running a drill full speed and pushing as hard as they can, but for someone drilling through a cap like this and trying to be careful it is extra insurance and WILL do the job.

Not the right depth, but you get the idea:

[versionpardner]

I'm gonna be that idiot but I drill out my cover with a regular bit and pried it out with a small flathead screwdriver. The key is restraint with the drill. However if I knew about the homemade drill stop I would have used that.