Driling My Discs

[mason79]

Originally posted by DiverRay
Mason,
I (gasp) held the disk down by hand!! And no, it wasn't that hard, There is a LOT of mass, so it didn;t try to spin very much.
Ray

you are pretty big, you have met me, do you think it's dangerous for me to hold it down?

[mason79]

Originally posted by Dennyz


I don't have a drawing of the pattern to send. The pattern is pretty easy to set up, however.

If you notice, the top hole lines up with the previous set's bottom hole. This makes it easy to create a template that locates on the rotor's center hole and only has locations of one set of holes.

I center punched a set of holes, rotate the template (indexing with the last (bottom) hole and punch another set.

To make sure the right side and left side would match. I started from a rotor mounting bolt hole.

ok then what was the radius of your sweep,

if i measure the straight line distance from cl of the first hole to cl of the last hole of a set of holes, i can place this measurment on the sweep, and space out the holes equally.

you have 12 sets of hole per discs right?

then i would put a clock pattern on the disc with straight lines radiating from the rotor's center, starting the first set of holes from a rotor bolt hole.

then i'll use this pattern and gap adjacent lines from bottom of one to the top of the next line; ccw for the right rotors and cw for the left rotor.

is the rear rotor the same dia and the fronts?

do you think i am on track or off track? thanks

[Dennyz]

do you think i am on track or off track?

You are right on track.

There are 12 sets of holes. The top and bottom holes are on the hour (every 30 degrees). The rest of the holes are on the second (every 6 degees).

The top hole is centered on the top wear line and the bottom hole is centered on the lower wear line of the rotor. The remaining holes are centered between the top and bottom holes and where the 6 degree angle intersects. This is what creates the arc.

I drew the lines in with a pencil to make the visible to the camera. You are looking at the template as it would apply to the right side.

Remember to start the pattern from one of the rotor mounting hole at 12 o'clock so the right and left side will match. You will notice that one of the mounting holes is centered on a rotor spoke. That is where I started.

Yes, the rear rotor is just like the right front rotor.



Happy drilling!

[mason79]

Originally posted by Ken Talbot
Mason, try the pdf template files on this link I just checked it out and did not have any trouble.

As you scan the article, you'll see I had no trouble drilling the rotors with plain, garden-variety cheap drill bits. Mind you, I did use a fairly decent sharpener to change the bits to a better split point, and ket the bits sharp. The the rotor material is not difficult to drill if you use a low feed speed, cutting fluid, and a freshly sharpened split-point drill bit.

hey ken,

do all drill sharpeners have the ability to creat a split tip on bits?

[planedick]

Drill sharpeners...

Only sharpeners that do 135 degree split point are professional models, way too expensive. However with the years of experience I have doing that I can do it on a bench grinder. Get some old drills and practice, you can probably do it too. If you buy them that way and don't wear them out too much you can put a new edge on them pretty easily.

[Ken Talbot]

Originally posted by mason79


hey ken,

do all drill sharpeners have the ability to creat a split tip on bits?

I'm only familiar with the Drill Doctor units. Their models 500 (1/2" max) and 750 (3/4" max) will both do split points. I've got a model 750 on its way for my BL and it cost US$119 plus shipping. The lowest price I've seen online for a model 500 is about US$88. They also have a model 350 that can be had for about US$59, but it will not do split points.

[mason79]

Originally posted by Ken Talbot
Mason, try the pdf template files on this link I just checked it out and did not have any trouble.

As you scan the article, you'll see I had no trouble drilling the rotors with plain, garden-variety cheap drill bits. Mind you, I did use a fairly decent sharpener to change the bits to a better split point, and ket the bits sharp. The the rotor material is not difficult to drill if you use a low feed speed, cutting fluid, and a freshly sharpened split-point drill bit.

since this will be my only drilling project, how much cutting fluid will i actually require? 8oz? 4oz?

[Ken Talbot]

Probably not even an ounce to drill a set of three rotors. Just buy the smallest bottle you can find. The 4 ounce bottle I bought still has lots left.

[mason79]

your the man!

[mason79]

there are different sizes of center punches i have learned which should i use?

[Ken Talbot]

I use a 1/8" punch for just about everything I do, but that's really because the next biggest size in my toolbox is dull. Like a lot of tools, you just want to be sure your punch is sharp enough so it doesn't bounce or skate all over the place when you give it a whack. You don't need to keep hitting it till it has produced a 1/8" crater either. A crater between 1/32" and 1/16" will be plenty if you are using split point bits.

[mason79]

thanks, should i bother the check the thickness of the disc rotor and account for the scoring, or just drill and pray? or play rather.

[planedick]

Scoring?

I wonder why you would put so much effort into drilling discs that are scored. If they are badly scored they may be no good anyway unless there is enough thickness to clean up and still be thick enough.

[mason79]

you know that i am bored, and i am not buying new ones, they stop fine, i'm doing this mostly for show, i will ride 5k miles a year, so i'll look good for 5 ....maybe....

[mason79]

2 down 1 to go

thanks guys again for the xs university.

drill press 39.95 plus tax

cobolt drillbit 2.50 ebay

center punch 4 bucks

cutting fluid 4 bucks

protractor 4 bucks

countersink 2.00 harbour freight