Sign in to follow this  
Followers 0
AlamOso

CNC mill for shaping lures

22 posts in this topic

Check out my CNC mill that I set-up in my garage for roughing out lure bodies. It is a benchtop model that is controlled by a PC, like the kind a jewelry maker (or ID bracelet etcher) uses. It took a lot of tuning and and programing, but is working out well now.

This link should take you to a page with some short video clips and photos http://www.rivercitylures.50megs.com/mach/mach.htm

If anyone else has thought about getting a similar machine, maybe I can help you get started.

Garrett

Share this post


Link to post
Share on other sites

Very intriguing piece of machinery.

Is that made from scratch, or is that some sort of kit or finished machine?

I have previously built a duplicating machine using a similar concept, only the cutting bit remains stationary & the lure blank moves on 2 planes while rotating 360 degrees.

My machine is simplistic & lends much to improvement, but computer controlling the process interests me.

Very nice setup!

Share this post


Link to post
Share on other sites

I?ve noticed the Dupli-k8r. That machine probably comes in real handy for quick prototyping and making replicas. I would imagine that you can easily change-over to new lure patterns with little set-up trouble.

This unfortunately is not the case with a mill. Once you do have a design set in stone, it is great for getting consistent repeatable parts though. I don?t have the expensive 3D code generating software that makes prototyping easy, so I had to write the program manually. It is over 12 pages of text, and took about 50 hours. If you include drawing time and refining the program, you can easily add another 50 ? and that?s before I got the first good part!

--A little about the theory of operation: the lure is broken down into a series of ?dot to dot? points which the cutter follows. The tool pathway resembles a topographical map, starting at the highest elevation, and making circles around the contours. Imagine a road at the top of a mountain, spiraling around the mountain several times until you reach the bottom. Now the mill recognizes points in space (in the 3D work area). In your program, you tell the mill where ?home? is (or X0, Y0, Z0). And then you tell the mill how far each point on the outside of the lure body is from ?home?. You give the mill the order (sequence) in which it is to travel from point to point, and the result is that it removes the excess material. You must put the lure ?block? in the fixture in the same place every time (relative to the ?home? position). The language is called G-Code, which is really just based on simple Cartesian coordinates, like a map. It has been used extensively in industry since the 70?s, but only recently have machines and processors become affordable (I hope that I?m not too much of a bore here).

The machine I got was a ?packaged? deal, ready to go out of the box. It is the MAXNC 10, and can be found at www.maxnc.com. The distributor I bought it through was www.positiveflow.com for about $1300. I also had to add an anti-backlash upgrade for about $200. That is probably why I still do not own a boat. I run it from an old Win95 PC, and it will even work with a 386. There are some competitors out there also.

Anyone can learn to operate it and write code. I had to play around with it for about 2 months before I was comfortable though. And, I have a background in CAD and machining. It helps to know someone to give you pointers with it too.

-Garrett (apologies for the lengthy post)

Share this post


Link to post
Share on other sites

Great stuff,

Ive actually researched awhile back,... looking at the machine it runs off of 2 steppers & a belt driven cutter, correct?

if someone could actually get the "software to motor" calibrations right, could something similar be done using allthread [20] threaded rod for linear movement?

Ive seen some sites where model airplane enthusiasts have crafted homebuilt CNC's to make propellers & body ribs, etc. from balsa.

is this software you use proprietary, or open source?

Thanks

Share this post


Link to post
Share on other sites

There is no reason why you couldn?t build a machine and retrofit it with NC. I imagine that you could have one axis motor rotate (index) the lure, say, in 10 degree increments. The other two axes would make a pass from nose to tail of the lure, and cut the right contour (height) for that particular degree of rotation. After 36 passes (one full revolution), you would have your lure.

As far as the software to motor calibration (parameters), you can buy a control module from MAXNC that is ready to go. All you have to do is plug in the printer cable (special wire arrangement). It has three stepper motor outlets ? and a 110V for your spindle motor. It does use 1/4-20 all thread, and the motors in the packaged deal are already calibrated for that. I did switch from the V-Thread to Acme with antibacklash nuts. The software is proprietary, but is sold by itself or offered free in a packaged deal from these people www.discountcampus.com/store/maxncpage.htm

You are also able to buy directly from MAXNC. A guy I work with makes machines with NC from scratch. I?ll talk to him and see what controls he uses. MAXNC is the only thing that I have first hand experience with.

There has to be a faster way to do it than the way I have set-up. At about 30 minutes per lure, you are lucky to get 20 on a good day. The beauty of the system, though, is that you put your part in, push a button, and walk away and do something else.

-Garrett

Share this post


Link to post
Share on other sites

That's just plain damn COOL!! I loved the clips. Thanks for sharing it with us.

Skeeter

Share this post


Link to post
Share on other sites

Man that machine is cool does it actually rotate the bait, or do you have to turn it and make another pass? I got a Duplik8r but haven't used it much lately, man a cnc duplik8r that would be a fun project.

Fireball

Share this post


Link to post
Share on other sites

The way I have it set-up one side of the lure orbits under the cutter. The lures (in pairs) are fastened to a jig via screws through the nose and tail eyelets. After it finishes shaping one side, you have to unfasten the lures and flip 180 degrees to let it run its cycle on the other side.

Rotating the bait could be done with a fourth axis (basically adding a rotating chuck to the mill table). With this concept you could move the table under the cutter, from nose to tail, while rotating the lure (see also my previous post ? cutting "every 10 degrees or so").

Share this post


Link to post
Share on other sites
There has to be a faster way to do it than the way I have set-up. At about 30 minutes per lure, you are lucky to get 20 on a good day. The beauty of the system, though, is that you put your part in, push a button, and walk away and do something else.

Heres a few things you can do,

fisrt thing is to upgrade the acme thread or all thread from 1/4 to an absolute min of 5/8. run a 2 inch long nut (that attached to the table) made out of oil light or bronze.

goto your local machine shop and have the table built with 1" min alum plate

then replace the dremil tool with a router.

Also in the vid the cutting tool is stick way to far out of the chuck, if you just shorten that you can increase your feed rates. #1 thing is rigidity the dremil should be changed.

Another thing to do is buy a drill press(just a cheap 100 dollar one) replace the bearing so you can side cut(about 20-30 bucks)

use the drill press spindle for the spindle on the existing machine.

As far as code. if your good with cad systems ie auto cad even autocad lite. When you make any drawing they all produce numbers(I forget the exact meathod to get them) you can copy them for your code and add very little text(mainly you would add the g-codes and m functions)

Also for tooling in a machine that is not rigid dont not use carbide. use tool steel for wood and plastic(use water and a soap mixture for plastic or buy coolant) carbide is not as sharp as tool steels and is to rigid to cut with.

I noticed that in the vid that the tool is pushing and not cuttting, what bit(tool) were you using? when tools are not cutting they put vibrations into the machines.

if you want a good table goto a machinery tool place and buy a scrapped hand mill(bridge port). you can rebuild them and add cnc retrofits.

Now granted I mainly mess with retrofits and machines that use dc and ac spidle drives and and spindle controls for adjusting spindle speeds, but there are mainly things you can do cheaply to make a cnc machine

Just remember one thing rigidity is the one thing that makes a machine work. there are mainy ways to do this and stilll have a machine that weighs under 300 lbs and should cut your parts in a few mins.

Delw

Share this post


Link to post
Share on other sites

Hi, I'll jump in here.

Here is a site of some cnc type stuff.

http://www.super-tech.com/

We have the Supercam software. Have it hooked up to a plasma torch for 2D stuff.

The software also does 3D ax

On autocad, we print our drawing to a plot file (.plt ) and that is what we use to import in to the Supercam software to run the torch.

Share this post


Link to post
Share on other sites

David.

Thats what I was thinking of the .plt file(plotter file). thanks.

That would save someone a ton of money.

if someone is good at writing scripts they can write one for a plot file to add in the g c0de.

Delw

Share this post


Link to post
Share on other sites

Hey Del are any of the mini mills better than any of the other or do you know much about these? I would be interested in getting one setup to make all sorts of stuff just not sure which mini mills would be the best for my application. I'm not going to be cutting hard metals probably aluminum and wood mostly. I was looking at maybe getting a manual mill and using a retrofit kit to make it cnc later down the road any ideas?

Nathan

Share this post


Link to post
Share on other sites

If it dont weigh at least 500 lbs its not good for cutting alum or any hard metal.

the mini mills where are they from?

the mills in the pics wont cut alum , steel

your best bet is to save your change and buy a used hand mill looks in the paper you can get a bridgeport or look alike mill forunder 1000. ive seen them done to 200 bucks.

a retorfit kit can cost anywhere from 500 bucks to 20,000

Delw

Share this post


Link to post
Share on other sites

Seems to be a lot of questions and good advice. I?ll try to answer as completely and briefly as possible (in reverse order from the last post on No. 17th). There are a number of mills available. Some include http://www.microkinetics.com/cncmill.htm http://www.taigtools.com http://www.sherline.com and the one I use, http://www.maxnc.com/page3.html (the best priced). For occasional use, cutting aluminum (like T6061) can be done, but you cannot remove much material per pass (.010). If you are making steel molds or even hogging out aluminum, you will need heavier duty equipment, as mentioned by Delw.

My mill came with DOS based g-code generating software, but for my application, I just opted to manually enter the XYZ coordinates because of all of the editing involved anyway. I use AutoCad, and imposed the tool paths over the 2-D lure drawing. By sectioning the different views at set distances, I identified the points using the distance enquiry function (like a 3-D wireframe). I could really use some good software to generate the code.

A faster lead would help. Right now, I?m maxed out at about 10 ipm. This seems to be all the motors can handle. It is a very small machine, like the kind a jewelry maker uses to etch ID bracelets. It does serve its purpose well, though. I?m not using the Dremel model. Delw, you are right about the cutter being too far out in the video. It could stand to be chucked-up a little higher. It is fully engaged in the collet, but since I?m just cutting wood, composites and plastics ? it cuts like butter. So, tool deflection due to extra shank length isn?t much of a concern. The cutters shown are conventional HSS 4 flute end mills, the first a 1/8 ball and the second a 3/32 square center cutter. Maybe the video quality is poor, but the cutter is turning (not sure of the rpm, probably about 2500 ? rheostat controlled with no read-out). When you mention ?pushing?, do you mean the part is flexing?

Share this post


Link to post
Share on other sites

Well the machines I have been looking at aren't huge machines but are bigger than some of the smaller mills. http://www.grizzly.com has a mini mill for a pretty descent price, haven't found a cnc conversion kit for it online yet. And http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=44991 http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=47158 Homier (Speedway) SKU 03947, $399.99 all of these seem to be made by a company called seig which there site shows mills from small to larger versions. I found a site at www.mini-lathe.com that has some review on these mills and they seem to be cutting aluminum with these machines.

Nathan

Share this post


Link to post
Share on other sites

Fireball

those mills wood work but you will need to add good bearing to the spindle so you can do side cutting. the bearings in them now are mainly for drilling bearings probally run about 20 bucks for 2

I. B. Cranking:

What I mean by pushing is instead of cutting the endmill is rubbing(pushing) the material.

When cutting on light duty machines you actually want the tool to flex. this will put a constant load on the bearsing to one side so you dont get chatter/vibration.

you can also help the rigidity of your machine by getting rid of the collet and putting in a sleeve. Collets are not good for endmills at all. get a sleev in there with one slot and maybe a flat to tighten it down. you can modify your holder to use both.

The main this is , is to keep that tool as close to the org spindle as you can.

Delw

Share this post


Link to post
Share on other sites

Guys this is a great thread..I'm impressed with what you have done with this set-up.. I was tool and die maker for Armstrongs products co. and then 15 years for National Mine service co. where we made deep mining equipment.. I programed and ran NC and CNC machines on a daily bases

of course the machines I ran were 19 feet long and 25 feet high.. but really its the same set up..to do this on your own..my hats off to you!

great job!..

they are such a thing as a tracing mill that will cut a part from a print

I have seen them but I have never ran one..I ran a EXCELL_O machining

center.. it didn't use a computer .. it used a tape..reel to reel where the programing was stored..the program was written on a programming tape computer then loaded in the excello

I think this is a great project..I'm going to start looking around to see just what it would cost to put this whole thing together

Littlebear

Share this post


Link to post
Share on other sites

Well just about got my CNC mill complete, still got a few things to do but it's coming together nicely. One question I have is what cad software are you guys using, or are you just using g code?

Nathan

Share this post


Link to post
Share on other sites

All of the fancy CAD-CAM software ends up translating your object into G-Code. I use AutoCad to draw the object, but in writing the code I just manually identify the tool path (like dot to dot), and write the XYZ coordinates to a text file. Any good CAD program has the capability of identifying the coordinates for you. I recently found an older copy of TurboCad at Half Price Books for $15. It should be fine for this manual translating method. You could spend a lot more for G-Code generating software, but you will still inevitabily need the basic skills of editing the G-Code and "tweaking" it a little. It's not that bad. Once you can carve your initials into a block of wood, you're ready enough for production.

Share this post


Link to post
Share on other sites

Thanks for the information, I have been looking at cad software such as Rhino 3D and Bob Cad/Cam. I went a little different route than you did by purchasing a manual mill and buying a conversion kit for it ended up costing about the same price. Thanks again.

Nathan

Share this post


Link to post
Share on other sites

Nathan,

my opinion you did the best way possible, as long as the manual mill is rigid, what brand and size did you get?

ALso on the conversion did you get the three axis one? or just the 2 axis one? What brand conversion did you get?

Bobcad is a good software for just beginning.

Delw

Share this post


Link to post
Share on other sites

Hey Del I got the Sieg mill it's the one from Harbor Freight (no shipping charges) I talked to a guys who makes table top injection machines and asked him what he uses to make his mold and he told me how he did his mill. So i pretty much copied his mill, it's a 3 axis mill with a kit from www.KDNtool.com, I purchased the steppers from ebay and the drivers from Xylotex. I think it will be a descent machine to play around with, I did my homework and looked around alot before I bought anything. It's still gonna take me sometime to get it all together and up and running but I'm not gonna rush it. I think it will do alright for what I wanna do but we will see.

Nathan

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now
Sign in to follow this  
Followers 0