Advice Needed for CNC Machine - Laser vs Mill vs Drag Knife

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daCoops2002

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Hi All
I'm new to the forum, but I've been doing various bits of research into Lasers and CNC machines on and off for a year or so. I've started a business that specialises in wedding based stationery and other related items. Ideally, I'm looking to expand into the standard set of "laser cut" wedding invites as well as various small name tag type gifts, but also want to try to do a few different things such as engraving invites into acrylic or wood, and cut-outs of names (for place names) again in acrylic or wood. The card stock that I use is a very thick 540gsm paper "board" type material, so it is very different to the usual stuff that invites come on, and is a shade under 1mm in thickness. I'm guessing that the thickness of acrylic or wood that I'd need would be around the 3mm to 4mm mark.

I know that this forum is more related to actual woodworking, but I found a similar discussion here cnc-machine-v-s-laser-cutting-machine-t48574-15.html and thought I'd ask again, esp. since I'm guessing things have moved on in last 8 years, and also I'm finding it difficult to find some good advice that's related to sourcing things in the UK.

So I'm looking for a DIY kit/plans to keep costs down (~£1500 max) that will allow me to do the following:
- Cut intricate shapes into thick cardstock - up to a size of A3 (for large table plans etc)
- Be able to cut slightly less intricate shapes (scroll/handwritten text style) shapes into light wood and acrylic
- Engrave fine text again into acrylic/wood.

I've got a feeling that a single machine may not satisfy all my requirements, which is why I've been trying to find a modular tool machine that I can swap out a Spindle for a Small wattage laser, or even a drag knife. I don't think a drag knife will be able to cut the card adequately, but I've come across something called an Oscillating Tangential Knife, whereby the direction of the blade is controlled which can lead to sharper shapes, and since it oscillates up and down it can cut thicker materials. Again, can't find much info for UK based suppliers or options?

An Epilog Zing 16 might be an option but some of the prices I think are around the £7k mark which is way out of budget, unless there's a 2nd hand option for these?
Some of the Kickstarter options are appealing, but they all seem to have small footprints, hence why I'm exploring a complete DIY option.

I'm worried about the various Chinese options but from a safety and support perspective. I have heard that with some time and effort their CO2 laser machines can be set up and calibrated to a high standard, but not sure if I could justify the amount of money and risk if something goes wrong vs having a UK supplier for parts/pieces/plans etc.
Any advice from anyone on certain machines that I can search for - or possibly other sites that I can ask advice on (maybe one that is more suited to stationery etc?)
Many thanks for reading! Hope someone can help!
Cheers
 
I haven't checked the details against what you've asked for ( :roll: ) but the Stepcraft machines have interchangeable heads. Might be worth exploring. Tools currently available are here.
 
Hi All

Thanks for the very prompt replies!

I've stumbled upon Stepcraft previously, but only seen Ooznest in passing mention of other forum posts, and I need to take a look at either of them. I can't remember if it was these, but I found a few articles about people mentioning that one of them was based on belts which gave slightly lower repeatability and accuracy over the more expensive Screw driven axis or something?

When buying a CNC machine, when do you need to worry about whether its belt vs screws? e.g. Is it for when you're milling hard materials like aluminium and metals and there can be high resistance and possibly slippage on a belt I'm guessing? I've no idea whether I need to be concerned about this when buying a DIY plan. All I know is that Belts should be cheaper?
 
Hi and welcome to the forum,
Good questions for your first big post :)
You mention you have done some research already so will probably heading in a more or less defined direction in the back of your mind. You've asked about 3 very different ways of using a CNC controlled machine to achieve similar ends. There are some very good chinese machines available and yes you can get a dud but from the research I've done myself (YT Reviews etc) the bigger companies do seem to be fairly decent regarding warranty etc. DIY would, i recon be the best way for you from a learning experience point of view and it would allow you to build a machine capable of having swithcable head units so you can get the benefit of all 3 types of machine. I would suggest that if you are going to make anything that involves cutting/milling etc rather than just burning in then a screw driven system would be best over all, especially if you decide to use hard (dense) wood or soft metal. As, as you have suspected a belt system could lead to alignment and repeatability problems depending on the material being worked and and the head fitted.

There are a lot of sites offering bits but I have found the below to be very good:

https://uk.banggood.com/

hth
 
So after a good few hours of research last night looking into both the Ooznest and the Stepcraft, I've come to the conclusion that 1) My budget may be on the thin side to satisfy all my requirements, and 2) I might be better off (and possibly get better results) if I focus on getting a machine per main requirement.

Reading into both the Stepcraft and Ooznest, it looks like the Stepcraft has an edge in terms of overall rigidity from a few of the odd comments in various forums, but both look to be good CNC kits. I was impressed to see that the Stepcraft had lots of options and tools, and mainly the Tangential Oscillating Knife part, which seem to be not much mentioned in various places. However, adding it all up it gets very expensive. For the size that I'd like to produce on, I'd have to get the D-420 version, and by the time that I add on a router/HF spindle and the Knife (which I'd then hope is capable of cutting what I want) the price begins to get to around the 2000 Euro mark. Not sure how well the 3W diode laser works for engraving or cutting thin material but seems a bit expensive for 550 euros - esp. when on aliexpress (or probably even banggood if I looked) that I can get a 15W diode laser complete with an A3 gantry CNC for around half of that price.

The Ooznest doesn't look as a "mature" offering as the Stepcraft in terms of ready made tools and options, but it's great that it's supplied from the UK. I think that the dragknife won't be suitable for what I need, and certainly needs to be the oscillating variety if I'm going to cut thick paperboard.

So...thanks for the great intro to the forum, but I think that what I need to do is to go back to the drawing board and possibly narrow my requirements down to what I need most. i.e. whether I focus on just the very intricate paper/card cuts and look for a machine specific to just that, or focus on the acrylic/wood cutting....
 
my £0.02 worth......

DIY is not the route to go. £1,500 will get you more physical things per £ but when you factor in your time you will quickly reach a comparable budget to an off the shelf solution. You need to work out what you want and if it is achievable within yours and your customers expectation. Laser cut card is one thing and makes perfect sense in the context of what you want to do but I would say that cut acrylic and wood can quickly look tacky unless done right - that takes experience and time. Make sure that what you think you actually want as an end product will look professional and in line with your business.

To answer some of your queries and some you didn't ask;

Drive mechanics
There are several factors to consider other than screws and belts. Yes screws and belts are a huge element to this but not the key driver. As others have said you will need screws if driving heavy loads but to be honest belts are perfectly good for lasers. They can maintain reasonable accuracy in 3D printing and they can often do prints taking days to output. If a 3D printer can maintain reasonable accuracy of XYZ coordinates over 48 hours I'd say that's a workable solution. The reason belts are used other than the main one of cost is typically speed. Moving a ballscrew assembly quickly creates all sorts of issues such as inertia and acceptable cut times. I wouldn't rule out belt drives as they have their place, just depends on the end function. For cutting card with a laser then belts will be fine. Anything thicker is a bit grey as you can cut thin plastic and wood stock with belts but this in itself limits your ability to do anything above this. If you use a spinning cutter tool head, i.e. router then use ballscrews.

Motors
Not much to mention here as your budget is realistically only going to cover stepper motors. You can get servos which have advantages over steppers but unlikely to enter your situation. I only mention them as you may end up buying a used machine with servos and even if you look at new kit, someone may try to talk you into buying the servo option. Steppers will be fine for what you want.

Guideways
The drive mechanics are key but they need something to move the material and / or the tool head along. These are your guideways and again at your budget range you are probably looking at shaft linear bearings, possibly square rail (google Hiwin). The oozenest machinea and a lot of the entry hobby machines use v-rollers on extrusion. Perfectly fine for low to mid range 3D printers but give it a miss for a machine used for business purposes in my opinion.

Controller / software
This is the electronics that drive everything. A good machine supplier will make a point of describing their controller and its origins whereas others will tend to ignore this component. The controller will dictate (not always) what software will work with it or come with it. A cheap controller will almost certainly have bad software with few routes to expand the system. Essentially speak to your supplier and ask basic questions such as replacement costs if the controller fails, what can it do now and further down the line. Is the controller / software supported in the country the equipment is used. Google the software that you think you may be using and find a forum or user group if applicable. A decent controller / software combo will pay for itself quickly, it will allow nesting and batch cutting making best use of your stock and time.

Tool heads - Lasers, cutters and knives
To start with lasers, unless you are buying from a reputable source, it is a complete skeet shoot. The wattage rating is often an arbitrary number that may or not be possibly close to the actual output. Laser tubes are often more reliable but even then it's dodgy territory. You will generally get solid state (diode) lasers up to around 15W and tubes will start around 40W. There are exceptions to this but at the end of the market you are looking at this is probably about right. Cutting card at over 500gsm is going to take at least 40W in my opinion else you will be looking at multiple passes increasing the risk of discolouration through unnecessary burning. Ideally if I was in your situation I'd be looking at something over 40W given you are looking to expand your business - it will keep your options open.
Router / spindles add cutting / engraving options but this now moving away from laser cutters and into flat bed 2D CNC.
Drag knives are an odd one again, good ones aren't cheap and cheap ones don't work.

In my opinion, avoid alibaba, aliexpress, banggood. These are the lowest cost denominators in terms of cost effectiveness and are just drop shippers with no interest in return business - good for tinkerers but not for business solutions. That said, don't be put off by Chinese machines. Chances are a lot of UK suppliers are just rebadging them anyhow. The Chinese put out decent kit these days, we are all just used to the Ebay and cheap Internet outlets. I would also avoid kickstarter - you could end up in limbo for years with no end product.

I would not try to get a single machine solution for your multiple requirements. It will be bad at everything and good at nothing. I personally think you will waste time and money and regret it.
I would start by buying an off the shelf A3 laser cutter with 100W minimum laser tube (and buy a spare tube at the same time if you can). Ensure it has supported controller hardware and software and ask to speak to current customers. This is clearly going to go way over your budget but given this is a business this is the route I would take, factor it into your cash flow forecast and take the plunge - I assume it will increase your ability to increase costs and sales else why do it?

That all said, I appreciate you may still want to go the low cost route in which case wait for an Ebay sale of a 100W laser cutter and maybe get a CNC 6040 (with 800w or 1.5Kw spindle) and have a play to get a feel for it as an option and move up when you can or it makes sense. You can get 100W cutters with a decent cutting envelope (700x500mm) for less than £1000, just need to be patient and buy one second hand (or pre-owned in Ebay speak). At least that way you can collect yourself and ask the seller to show it working before you take away. I've also seen new ones go for £1300 - again patience. The 6040 CNC machines are actually quite usable, will allow you to play around with engraving and cutting acrylic. Factor in buying Mach3 at £100+ and a spoil board cutter at £70+ as the bed will almost certainly not be flat and you will need a flat spoil board to engrave satisfactorily. Happy for you to PM me if I can help.
 
Hi Shed9

Many thanks for all those details - that's given me loads of information to factor into my search. I've come to the conclusion that you're 100% right about trying to get a machine that can do everything - I think that I'd end up spending a lot more than desired and ultimately ending up with a machine that can do bits of everything but giving mediocre results in all for what I want to offer.

I'll start scouring ebay and keep an eye out in some laser forums for 2nd hand machines that could suit my budget. Cheers!
 
daCoops2002":2kz8n3k9 said:
Hi Shed9

Many thanks for all those details - that's given me loads of information to factor into my search. I've come to the conclusion that you're 100% right about trying to get a machine that can do everything - I think that I'd end up spending a lot more than desired and ultimately ending up with a machine that can do bits of everything but giving mediocre results in all for what I want to offer.

I'll start scouring ebay and keep an eye out in some laser forums for 2nd hand machines that could suit my budget. Cheers!

No probs, happy to sanity check your choices before you push the button on buying one if it helps. I'm sure others would add their input as well. Even at the low end of your budget that's a lot of change to put down on a machine that you are new to.

You effectively need two machines, a dedicated laser cutter and a flat bed CNC router. The Laser will cut card and thin stock along with some options in engraving whereas the CNC router will cut most solid materials up to the limits of the machine. The CNC router can also be fitted with a drag knife but that depends on the budget spent on the router and its own toolhead options. To be honest most CNC routers could be adapted for a drag knife just depends on the type as controlled knifes need a reference point relevant to the tool head - hence why the good ones cost.

One thing to add with drag knifes, they are just as useful in making your own packaging. They can take a layer of packaging cardboard, cut the outline and the fold lines - hey presto, custom packaging. May not be relevant but it may add ammunition to your decision making.

I know they are expensive and there is a lot to be said for making your own equipment but from a business perspective I'd get the best you can afford and budget it inline with your business plan / forecast. If you DIY or buy cheap you will likely regret it however good gear will always come through and hold its value to some extent.
 
Just my tuppence worth, Shed9 has covered things better than I could on the considerations.

I have a Stepcraft machine. I also worked (a long time ago) as a CNC programmer. My thoughts are these.

Many machines are 'capable' of machining or cutting various materials but the cut rate is so slow it is only of any use to hobbyists. For instance I can cut cardstock with a home made drag knife very successfully but a reasonably simple card takes around 15 minutes. Add in the time to position and align each workpiece and cutting out 100 invitiations will get old very quickly.

The other thing often overlooked is software. I don't know what experience you have but I have found that many people fail with CNC as they just can't get it to do what they want either through using poor software or more usually not being able to use the software they have properly. I currently use VcarvePro which I find very intuitive. Your milage may vary dependant on what you are used to. All I would say is do look around for the best solution for you and try it out before comitting, just because it gets great reviews doesn't mean you will get on with it and it can make or break how useful CNC is.

My advice is to approach this from the end result rather than if I get this machine can I make it do this aproach. I purchased my machine from StoneyCNC, Rory who owns it has an excellent reputation for providing excellent advice and superb customer service. My suggestion would be to give him a ring and talk through what you are trying to achieve.
 
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