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View Full Version : Fab ideas, for router/cutter/miller type lashup...



RoadWarrior222
04-11-2011, 12:59 PM
Hi guys...

This will take a bit of 'splainin'...

This don't sound heavy duty, but I am pretty sure it will work. What I have is some normally very spendy high speed precision cutters, from 5mm to .8mm, made for running at 25,000 RPM. Then also I have a dremel router/shaper table, and a knockoff rotary tool that is quite beefy especially at high speed (I ported a head with one). Anyway, suffice to say that the tool mounts to the table, and can spin the cutters at 25,000 with a reasonable amount of torque.

So I can use this for precision cutting of flat sheet stock, or routing channels in it... I think it will shove the 1/4" cutter through 1/4" of steel if I feed it slow. Precision cuts get the smaller cutters of course.

Anyway... two projects I have in mind for "in the future" because they are contingent on things coming apart for measurements are port plates and a crank scraper... should be doable in thin stainless.

Oh another job, when I get the spare cam gears will be adjustable cam gears. Well a partial job for it, drill press etc will do a lot.

At present, I'm thinking only cutting would be freehand, don't think I can manage to route channels in other than straight lines, or else with simple jigs... (Okay, I'm halfassed thinking of how to make the endplates for a scroll compressor, based on string winding round a post)

Yes, accuracy will take a lot of trouble, it will all be cut to fit and continually checked and rechecked.

So..

What I'm really asking, is does anyone have any ideas for "trick" parts that I could try making with this? Or is there any places with project ideas/plans for this sort of thing?

I'm itching to "play" with it properly, but can't think of something to do which isn't dependent on getting other parts, and getting the "vehicular situation" to a particular state to do it.


Thanks,

RW222

RoadWarrior222
04-12-2011, 08:21 AM
So I was thinking I might manage to plunge cut real thin sheet, like stainless for gauge faces... but that's just bling and I don't know if I can be arsed for the amount of work it would take.... though if I ever get really enthused about making a "steam punk" rod, I might do it in brass.

One thing I thought of to try was to make an "auxettophone" amplification valve, which is like two comb plates which are activated by sound, allowing air to pass, thus using air to amplify the sound.... the reason that might be "trick" is that fuel droplets can be bust up by ultrasound, buuut... tiny ultrasonic transducers aren't a lot of use, especially when there's not a lot of air when the motor is "in vacuum" (There's still some but not a lot) So if you could use a transducer to drive an auxettophone valve that worked by engine vacuum, then it would fill the intakes with very high intensity ultrasound and atomise fuel extremely well.

I'm also thinking I could cut thin, relatively large tooth gears on it, but since they would be rather light duty, I can't really think of good applications for them. If only I could remember my tech class back in school where we drafted gears by hand with compasses... will have to look it up.. remember, clockmakers had a lot less than this to work with back in the day. Okay, if I was a glutton for punishment I could make a lot of thin straight cut gears as identically as possible, and spot weld them into a stack to make something that could hold a bit of torque but that would be rather tedious... although I could use an easily worked plastic and make a "model" by stacking them and then use that to cast a gear in alloy, then figure out how to clean it up... might be the sort of thing for a toothed belt drive like a supercharger or other accessory.... but there's probably easier ways to go.


Anyway, still casting around for ideas. Now it did occur to me that it might handle the same kind of project that is done by laser cutters or water jet cutters. So if there's projects/sites around for that with good ideas on I might like to try some of those out.


I have some other junk hanging around that I might be able to figure how to turn bits of this into a small milling setup, computer controlled, building up from single axis drive to 3 axis... though I doubt it will ever do anything very big, or to better than 10 thou accuracy...

I know it sounds like I'm contemplating using a jackhammer to etch a wineglass, but for personal stuff I don't care much about "reproduceability" because one can make parts fit each other with very tight tolerances, lap to fit etc... make slightly oversize to hand fit. Tedious maybe but you can get it done. The analogy that might work best is "Khyber pass copies" of firearms. Now some of these are highly skilled works of art that work very smoothly and shoot very straight... it's just Mr Kalashnikov's or Mr Colt's spare parts do not fit them and vice versa, even though they might appear identical.

Mopar318
04-12-2011, 08:40 AM
25,000 rpm is way to fast. You will ruin the cutting tools. Does that motor have power at a lower rpm? or will it stall?

RoadWarrior222
04-12-2011, 09:43 AM
It does have lower speeds..... BUT, these things are tiny, the surface speed at 25,000 RPM is not gonna be very high... running a .4mm radius cutter at 25,000 is only like running a 4mm radius one at 2,500. I got them from a yard sale, buddy had a shoebox full, father retired machinist of some sort, told me that was the speed they were used at. Looked the type up online somewhere when I got home and confirmed it. I should have written stuff down because that was a year or so ago and I've forgotten the details.

Mopar318
04-12-2011, 10:08 AM
It does have lower speeds..... BUT, these things are tiny, the surface speed at 25,000 RPM is not gonna be very high... running a .4mm radius cutter at 25,000 is only like running a 4mm radius one at 2,500. I got them from a yard sale, buddy had a shoebox full, father retired machinist of some sort, told me that was the speed they were used at. Looked the type up online somewhere when I got home and confirmed it. I should have written stuff down because that was a year or so ago and I've forgotten the details.

wow, .4mm is tiny. I would like to see this? I does not seem like you would be able to shape anything though. That would take alot of passes.

RoadWarrior222
04-12-2011, 10:31 AM
Yeah that one would be for precision cutting thin sheet or something, the 5mm dia one would be the one for shaping thicker stuff, that one might need to be at 15,000 RPM... That was radius, .8mm diameter, and that one is like a carbide burr, got a mix of burrs and spiral cutters.

RoadWarrior222
04-12-2011, 11:55 AM
Think I found something useful for info for drafting gears if I wanna do anything like that..
http://www.archive.org/details/elementsofmechan030118mbp