[prstone]

This is my first post here. This looks like a great resource.

I am looking for a CNC router for cutting .125" thick aluminum and plastic (polycarbonate). I would use something like Rockler's CNC shark but I do have some tool changes that have to be made and the CNC Shark family is not conducive to that.

I don't need an automatic tool changer. Manual is fine as long as it uses collets and it is repeatable. One of the parts I am cutting is 18" x 4" x .125" (aluminum). The other is 14" x 14" x .5" Polycarbonate. There are some other parts as well but if it will make these then it will cut the others.

Can anyone make a recommendation for an inexpensive machine?

I invented a new panel saw and need to make parts for my hardware kit.

Thanks in advance.

[boblon]

..prstone

You are right, this is a great resource. I am not able to answer your question about the 'best' router to get, but I am wondering if you actually meant to post in this section?
I don't know how much you've looked around the forums but this area is only one VERY small section of the entire forum. This is the area for folks who are interested in or have purchased from XYZ Gantry.
You might want to look around the forum catagories on the main forum page.
You don't give a lot to go on either. I think you'll find that VERY broad and general questions may go unanswered. Folks on this forum are great but some questions are just to wide open to be answered.
I don't know if you want to build or buy? I am a newbie myself and chose an XYZ Gantry mechanicals kit as a way to accelerate my build.
Have you made any of these parts your after?
Have you thought about having a batch run by someone else at the start?
If this is the only reason you want the machine it may take some time to recoup costs. I am NOT trying to discourage you, just not sure how much thought you've given to this side of things.
You say you don't actually need an automatic tool changer. Any machine can be told to stop and wait for a manual tool change and then continue. It does save some time to generate your code to minimize those tool changes.
Sorry I can't be of more help, but didn't want your post to languish here. If you look around the forums you'll get an idea of what folks are doing with their machines and what it takes to build one.
I wish I could be of more help to you.
Good luck on your product and venture.
BobL.

[ger21]

I don't think the Shark would be a good choice at all for cutting aluminum, as it's not very rigid due to it's unsupported rails.

I don't need an automatic tool changer. Manual is fine as long as it uses collets and it is repeatable.

All you need is an automatic Z zero setup. Big Tex has a Mach3 screen and macros to zero tools after a toolchange. http://www.cnczone.com/forums/mach_w...r_big-tex.html
My Mach3 2010 Screenset automates the process.

Can anyone make a recommendation for an inexpensive machine?

Define inexpensive? $2000? $3000? $4000?

[prstone]

Thanks BobL...

I am specifically looking to buy a cnc router and yes, I do want an XYZ Gantry router.
I am well aware of the business side of this equation. A small cnc router like the CNC Shark from Rockler would work if it had a spindle that could accurately change tool. They just use an off the shelf wood router which does not control the length of the cutter.

I will sift through the forums and see what I can find.

[prstone]

Gerry,

Thanks for the input. I am a research engineer and equipment designer for the Boeing Company. We have the original CNC Shark in one of our labs. It is very whimpey. The machines structure is high density polyethylene (not even UHMW PE). The latest unit (CNC Shark Pro Plus HD) has supported rails and is much more robust. The bed of the machine flexes as it is not made from a solid piece of material. It is made from Rockler's T-Bar extrusion (multiple pieces connected together). The bed would have to be replaced. I am looking to make a vacuum bed.

I have been an NC programmer (20 years ago). I have also written CAD/CAM systems. I have never been an NC machine operator.

The Mach 3 software looks very nice. Good macros for handling tool changes. This software looks like a must have. It handles the details of setting the cutter length efficiently for a guy doing manual tool changes.

I guess that I am looking for a spindle that will allow me to change cutters quickly. I will be setting up and machining 30+ parts at a shot. I will either have to change cutters on each part (two required for one of the parts) or do all the cuts with one cutter, change cutters, and perform all the operations with the second cutter. I would rather not remove and replace the work piece as this leads to inaccuracy.

Another option would be to have two routers, one for each cutter and just swap routers. I am confident that I could make hardware to facilitate Rapid router change a snap.

Any suggestions on a spindle?

[prstone]

Gerry,

I forgot to tell you what inexpensive is.

I think that $4,000 to $6,000 is a reasonable price range for this particular application.

[ger21]

You're looking at $2500-$5000 for an ATC spindle alone. And most of these are too big for a Shark.
Also be aware that you need a toolholder for each tool, which can run up to $100 each or more.
These are the cheapest options I'm aware of.

I have no experience with any of these systems, btw.

Midwest Rapid Tool
Avenger Cartridge ATC system
High-Torque Stepper Motor, Stepper Motor, Driver, Stepper Motor kit, DC Servo Motor, DC Servo Motor kit, Stepper Motor Power Supply, CNC Router, Spindle, and other Components. Automation Technology Inc

There is also another option in Europe, but I think they use smaller collets.
Werkzeugwechsel-Systeme - USOVO.de

[prstone]

Great input Gerry.
Those spindles look great but a bit on the expensive side just as you said.
I think I will develop a quick change router system. Much more affordable and almost as fast and good as an automatic tool changer spindle.

[dfmiller]

Unless you are planing on profiling thin aluminum sheet I don't think you will be happy with the XYZ Gantry system for cutting Aluminum.

There is too much flex in the Z Axis to hit any reasonable tolerance.
I have not cut any on mine yet but I am sure about the flex.
Its a great router for wood and plastic.

Dave

[Larken]

This 1515 router is in your price range. It cuts aluminum well too.

Larken Camtool 15-15 Table-Top CNC 3-axis Router system

Yes a tool changer can cost 5-10K extra. Just a colombo TC spindle is about 5K alone then you have the inverter, pneumatics and you definitly need saftey sensors, since if the tool comes loose at 24000 rpm, people can die !

Larry K