CNC Router verses CNC Milling Machine

[Dave Harrison]

what sort of size work are you wanting to produce ?

For sign work you need a router or laser cutter with a fair size bed. . I can’t really see why I signshop would require a cnc mill !

[Gary Gray]

Hi Dave

I am looking to produce Rim & Return letters up to 1 Mtr high and also to fret cut aluminum/acrylic panels measuring 1M x 3M

[Dave Harrison]

To cut large panels in either acrylic, ACM or Ali you are going to need a router, however routers are not the best machines to cut stainless steel, for that you are going to either need a laser or a water jet !
It’s all expensive stuff so be prepared for heavy investment. Of course with a bit of skill and extra time all of the above can be done with hand tools 🙂

[Gary Gray]

Thanks again Dave, hoping to put the hammer and chisel away. I think I will ask Santa for a router and a water jet.

Cheers
Gary

[Jim Kitts]

In theory a plasma cutter will also cut stainless, but is more messy and discolours the edges. Ask at a good metal shop.
jim

[Simon.Kay]

We went through the pain of making the same decision although our requirement was for a heavy diet of stainless 316 with other materials thrown in from time to time.

Although we ended up with a water-jet each technique we looked at – laser, router, mill, etc. – was an entirely viable proposition….according to the sales reps and demonstrating engineers.

My summary was as follows:-

Laser – quickest, most expensive route. In some respects, least versatile as primarily best for cutting metals (can do plastics after a fashion but you have to spec to do so and deal with fumes and gases). Appears to be a non-starter with composites although I’m sure someone would have had a go if we’d have pushed. Great if you want to do a LOT of components i.e. many thousands or tens of thousand per year. Be careful if considering second-hand machines as they may have big costs waiting to spoil your fun when you finally get installed.

Mill – very versatile and extremely gutsy – should last for a looong time with comparatively low running costs. Best for working with small components as can be pretty expensive if you want a decent machine with a large bed-size. Also work-holding (i.e. how component is held during machining step) can be a challenge as big tough aggressive tools can rip thinner sheet materials to bits (as I found out during an ‘exciting’ demonstration with 1mm 316). Agree with previous post that it is probably over-engineered for majority of sign makers (we only looked at because of our stainless steel requirement).

However, due to long-life of machines there is a good second-hand market and we got the impression that we could have picked up a unit for buttons to do smaller work. Never did though.

Router – I actually thought this was the best lower-cost solution as offers large bed size and reasonable speed and excellent versatility with most materials, but when you throw cutting stainless into the equation seemed to make less sense. There were a lot of unanswered questions over ability of router to cut stainless routinely. We felt that the machine would eat cutting bits all day and cost us a fortune in tooling. Also we wanted for engraving work, but the ones we looked at were clearly not as good as a dedicated engraver.

Water-jet – a great piece of kit, very versatile, can cut practically anything unlike laser and mill. We haven’t tried to do it but I’ve seen videos of lawnmowers, computers, mobile phones, burgers being cut. Cost is less than laser (but not much) and running costs appear to be about the same.

Be aware that the water can damage some materials if you’re not careful and I would suggest that you test everything you ever want to use before making a decision. Also there are some issues over ‘piercing’ i.e. the first plunge into the material; we specced additional options to assist with this.

What we’ve also found out since we got ours up and running is they can be very messy (unless you are fastidious about cleaning). You must create a separate area for water-jet as water and abrasive (for cutting harder materials) get spread around. As the water dries, the abrasive leaves a dusty residue which is a real nuisance and gets everywhere.

Personally if you are not doing a lot of heavy work then I think a router is best. The savings you’ll make over a WJ will allow you to buy a small or second-hand mill for smaller, tougher work.

For bigger, heavier work (like stainless) then you probably will need to consider WJ. Bear in mind you can’t do any 2.5D/3D work at all with the WJ as well, which would have been a big benefit of the router.

Most of all, don’t forget to invest in staff and training as acquiring the expertise will save you big-time on errors and mistakes but more importantly help bring you production efficiencies.

[Gary Gray]

Thanks Jim and Simon

That confirms a lot of what I thought, have looked at all of these options and come to the same conclusions. The router looks like the best option for me, I was hoping the milling machine would be as good as the router and do stainless steel… in a perfect world.

Thanks again guys
Gary

[Simon.Kay]

Glad I could be of use.

Bear in mind of course that we were looking at some fairly specialised components and had requirements that were a bit out of the ordinary. You may not find the same things we did when you do your digging!

Best of luck anyway.

[Marcella Ross]

hello Gary ……….. !! 😀