Drilled rotors

[Giggity]

Anyone have the pattern available? The link in Tech Tips no longer works.
Thanks

[fredintoon]

Anyone have the pattern available? The link in Tech Tips no longer works. Thanks

Hi Giggity,
Yammie brake disks are made of a stainless steel alloy that's tougher than old boots so a hand-held drill won't work too good at all, best use a drill press. Start with horkin' great centerpunch marks, 3/16" drill to start, finish with 3/8". Cobalt steel drills work best. Low speed, high pressure, lots of cutting fluid.
The pattern is all in your mind, the brake pads don't care. Just so the pattern you choose is sufficiently regular that it don't unbalance the disk.

[b.walker5]

I drew a CAD drawing a while ago that i was going to use as a pattern for drilling mine. Happy to email it if you have a CAD program to read it. It will plot full size on 2 sheets of A4 for you to tape together and overlay on your rotor.

[79XS11F]

In MHO by the time you ether pay to have them done or go through a pile of bits doing it yourself you are likely better off buying them done / refurbed. Without a good drill press and the proper equipment you might even mess them up and put them out of balance which will make wheel balancing difficult. It's really not the sort of job you want to be doing in your garage.
Rob

[b.walker5]

Agreed, it's a job that shouldn't be attempted by everyone, but anybody with a bit of DIY nouse, a half way decent drill press, a couple of good drill bits, and some cutting oil is more than capable of doing it. The only other things required are an accurate, symmetrical template or pattern and some patience. Granted there is a small risk of upsetting the balance but this would be easliy overcome by a good tyre fitter with the right equipment.

As a side note, for those interested in doing this, you shouldnt need to worry about countersinking the holes. It's time consuming and not nessecary, and it makes no difference to the brake pads. Just make sure you emery the surface of the disc a little to remove any burrs left by drilling.

[TopCatGr58]

Both tech tips fixed, links too!

Hey Giggity and others,

I found my copies of Ken's PDF templates, and uploaded them to the XS11.com server, Ken's ISP has a tendency to go down at times, etc. I also put the photos in the FORUM version, they were already in the drop down menu tips!

So..the PDF files are now linked and are housed on our server. You can access, download them and print them out for your use.
T.C.

[Ivan]

Go to your local industrial supply and get a straight flute carbide drill. Garr makes a good one. Straight flute drills are stronger than twist drills and drill a truer hole. Carbide is hard enough that you won't burn it up so easily. Use lots of cutting fluid and keep the chips clear. Use a drill press. Either be cutting or be clear of the work. Don't let the drill "float" on the work without cutting, that is the quickest way to dull it. When it starts getting easier and the drill is pushing through the other side, be really careful because carbide is very brittle and will shatter (think glass) and is NOT cheap. The best way is to have some mild steel under the work and drill into it, so the load on the cutting surface stays constant. Did I say carbide is NOT cheap?


A DRILL makes holes. A BIT goes in a horses mouth...you don't want those old machinists giving you hell about that if you go to buy one.

[b.walker5]

A DRILL makes holes. A BIT goes in a horses mouth...you don't want those old machinists giving you hell about that if you go to buy one.

So what is the machine that turns the "drill" called?

[Ken Talbot]

So what is the machine that turns the "drill" called?

Drill press...

And TC is correct, I'm still pestering my ISP to get my pages loaded after they vanished during a server crash back around Christmas. They're in Saskatoon - maybe I should be getting FredinToon to give them a friendly visit.

[Ivan]

So what is the machine that turns the "drill" called?

By hand its called a Brace. If it is a motorized hand tool, an electric drill or an air drill. If it just drills one hole at a time, its called a Drill press. If it has multiple drills its a Drilling machine. If it can move in more than one axis and the tool turns instead of the work, a Mill. If the work turns and the drill is stationary its a lathe. If they are stuck in cork and it smells like stale beer and cigarettes, Darts.

[b.walker5]

By hand its called a Brace. If it is a motorized hand tool, an electric drill or an air drill. If it just drills one hole at a time, its called a Drill press. If it has multiple drills its a Drilling machine. If it can move in more than one axis and the tool turns instead of the work, a Mill. If the work turns and the drill is stationary its a lathe. If they are stuck in cork and it smells like stale beer and cigarettes, Darts.

All of which take a drill bit, except possibly the mill and the darts, and if I ask my apprentice to hand me a drill and he hands me the bit only, then he's sweeping the floor for a week

[Crazcnuk]

I did mine with a drill press and a $9 set of carbide bits.

I used the template from here, but staggered the drill bit sizes, ie; I started with a 1/16" and went up in 1/16" increments. I also added an 8th hole, as there was lots of room left at the outside of the rotor.

Gave it a 'swirl' look.



I drilled through all 3 rotors at once, with one backwards for the left front.

[Ivan]

All of which take a drill bit, except possibly the mill and the darts, and if I ask my apprentice to hand me a drill and he hands me the bit only, then he's sweeping the floor for a week

Out of curiosity, what is your line of work? Around here none of the machine shops (even the big aircraft unionized shops) have apprentices. You can either do the job or not. The electrician's and mason's unions have apprenticeship programs, but I have never heard of a machinist's apprentice. Well, I did, but that was at a shop that fired a guy with 30 years experience because "they could hire a kid out of high school for 1/3 what they paid him". Their "apprenticeship program" was an excuse for not paying market value for work that equals market standard.

The electricians and masons actually get paid a fair wage for what they do, unlike we machinists in non union shops.

TBH, I would rather guys building my home have some great training. Hard to drag a mic across a house to see if it is scrap. You don't have to train a CNC machine, but I think not on building a house.

[oldyam80sg]

Totally off topic-but last year i applied for a job at a company seeking an all around maintenance person.They gave me an interview and all seemed to be going well until the money part came into play.The interviewer said we will call you.Called the job agency back and they said they were interested but seeking a machinist-Told the agency that is funny because i didn't even see a drill press let alone a machine shop there.The agency called the company and they told the agency we might get a shop later but not now.Last time i drove by the place it was closed.I have tried in the past to drill rotors but you really do need a drill press and some quality drill bits and alot of lubrication!

[Texas Rookie]

I used ken's templates, a drill press and a couple of $2.50 carbide bits (1/4") from HD and chainsaw bar oil for lub and did all 3 rotors in about an hour and a half. It is a messy operation however as I am still picking shavings and oil out of various parts of my anatomy. The secret: more lube, burned up one bit before i figured out the secret (more lube) then I used a squeeze bottle and continuously applied oil to the bit (whateva) and it cut like butta. i did chamfer the hole edges with a 1/2" bit and it looks very nice. Texas Rookie