Chombi1 

I'm not sure if my puny Dremel drill press would be up to the job....
You know, the drill press with all the plastic parts......
I won't be doing anything fancy or heavy, just some lighte ing holes on derailleur jockey wheel cages and bore some lightening holes through some bolts to replicate what the French pro teams did on their bikes in the 80's.
Might I just end up messing up a couple of SLJ derailleurs with my toy-like drill press?? Or has it been successfully done with such equipment?

Charles Wahl

Not having tried it, in my head, it seems like a) even spacing and b) keeping the holes in line with one another are the big problems you always see on homemade drillium. I like my Dremel a lot, but I don't think it's powerful enough to do this sort of work with any efficiency; you might end up ruining both an SLJ derailleur and your Dremel.

Chombi1 

My Dremel is the model 4300 so it's quite powerful but I agree that it is keeping the drillium holes spacing and in line that will be the challenge as I suspect that there might be enough flex in the hobby grade drill press that I might end up with bit drifting and chattering when I drill the holes especially on convex surfaces.....

thook

I don't think the motor on the dremel would be robust enough. I dunno....maybe if you spaced out driling time so the motor doesn't get too hot. Even then, would the dremel have an adequate slow speed? Having said that, it doesn't hurt to try. I'd get the DeWalt industrial cobalt bits, though. They have the pilot tip and don't hang up in that last little bit of material as it's finalizing the hole. I've been using them on a job building a pea fowl habitat using heavy gauge steel pipe as the framing. We have to drill a lot of holes for the fasteners, and those bits do the job better than other varieties I've used....and dulled....lol! Oh, and they stay put on the round surface....not walking all over the place without having used a punch first.

ps. If there's something valuable I've learned about drilling in this job, is to not press too much into the material. Let the bit cut....don't press through. As well, try to keep the bit nice and perpendicular to the surface best you can. But, maybe you know this already

repechage

Stiffness of the drill press "frame" mechanism is I think a big deal.

the surface where the drill bit engages if not perfectly perpendicular to the bit, the bit will want to wander.

a spring punch can help - lots of effort.
not impossible but... reference short jobber drill bits - less flex- less depth to the flutes making the bit stiffer.

xiaoman1 

Chombi1,
For best result, I think that you need a jig...can't find anything on the web to help you.

https://www.rouleur.cc/blogs/the-rou...ty-of-drillium
https://www.bikeforums.net/classic-v...-drillium.html
Best, Ben

ehcoplex 

Aw, don't risk ruining an SLJ......

Chombi1 

if anything, the SLJs have mostly flat suflaces (Except for one side of the RD cage plates.) which could make them maybe easier to drillium....

Atlas Shrugged

You will find it extremely difficult using the equipment you described. Even with a high quality drill press and toolmaking equipment this would be a challenging process. Perhaps find a piece of scrap metal and try drilling 10 equally spaced 1/8” holes in a precise line perfectly countersunk evenly. If that works out try a circle, again evenly spaced and countersunk. Master that and you should be ready to give it a go.

eeuuugh

I would 'blue' the part with a sharpie, use a set of calipers to scribe your layout, and centerpunch each hole to be drilled. Then bolt the part down to a sacrificial piece of scrap that can be held in your drill press vise. If you search on youtube for laying out and drilling a bolt circle, you'll find lots of videos on how to do this kind of thing.

AngryFrankie

I remember reading a story online a few years ago about a guy who became kind of famous in the bike community for doing drillium, when that was a thing. He talked about his templates a lot, like that was a big part of his success. I've seen amateur drillium in the parts bin at the co-op. It is not pretty. Have fun though. There is no shortage of cheap bike parts in this world!

satbuilder 

The person you are describing sounds like Jon Williams, known on this board as Otis. His work is legendary.
Gone way too soon. RIP

iab

The drill used is somewhat irrelevant. If it spins and has a depth stop, cutting aluminum is easy. Invest in fixtures. Holding and moving your part with accuracy is 90% of the job.

repechage

there was Frank Spivey
Velo-Retro: Peter Johnson
at the bottom of the page.

there was Art Stump.
can be found on the classicrendezvous site in the USA section.
art used a micrometer and careful control of his milling machine. Very hard to match.
I did see it exceeded, but that was a guy while had access to a CNC mill in 1974 his name ( raised!) in a slot of a Stronglight crank- back then the programming time was outrageous.
machine time? Moonlighting defense contractor work.

WGB 

Chombi1,
For best result, I think that you need a jig...can't find anything on the web to help you.

A few weeks back I was over hassling a local frame builder and IIRC he had a template for drilling either stem or seat post from back when making bike components to make them lighter and therefore faster was the rage.

I'll try and trace it down and at least photo it for posterity. Maybe if you have a name of a maker you could locate the template that you need.

Update:
https://www.instructables.com/Make-Y...ke-components/

Reynolds 

Those chainrings and chainguard look decadent.

Moe Zhoost

This project is a great justification for investing in a desktop CNC milling machine.

smontanaro 

There is someone on Instagram or Flickr (want to say "campagnolo kid") who posts his drillium including pix of jigs. I think he recently bought a small Proxxon mill, but I'm having no luck finding anything at the moment.

63rickert

Skip

Yellow Jersey up in Arlington has a late 70s pantograph for sale. Was used for all the panto-ed Rossin parts on US market. And for lots of other stuff. Talk to them. And go into production.