Generally speaking in our world feed rate is the rate at which the cutter will be moving around when actually taking a cut (i.e the cutter is in the material). This should not be confused with rapid feed rates which are the rate at which the cutter will be moving when it is relocating above the material (i.e. when not cutting). Coupled with feed rate is plunge rate which as the name suggests is the rate at which the cutter will ‘plunge’ (down movement on the Z axis) into the material. Care should be taken with plunge rates as some cutters have a sharp point to them whereas other cutters may have a flat bottom and might need to be plunged slower. All this is generally referred to as feed rate or just “feeds” and is usually set inside CAM software.

Spindle speed or “speeds” is the speed at which the cutter will be rotating and is usually measured in revolutions per minute (RPM). Spindle speed may be controlled via CAM software if your spindle is connected to your machine control software via your controller however more often with machines at the lower end of the market, spindle speed will either be set on an inverter, in the case of the 3kW spindle or on the spindle itself, in the case of the Kress range of spindles.

Feeds and speeds are two of several variables that are linked together and finding the balance is paramount! Choice of cutter and the material itself and the cutter requirement itself are the other main factors to consider when trying to workout your feeds and speeds.

A little guidance is often provided on the cutter manufacturer packaging or documentation. Some cutters need to used at a certain feed and speed to prevent them from burning or leaving a poor finish. That’s fine when we are talking about large scale sheets of wood however there is less guidance available when we move away from wood and start looking at plastics and even soft metals.

This is where the CNCCookBook comes in!

Having had several of our customers find it of their own accord and report back that it had been an invaluable tool and at such great value for money of course we had to take a look and see if this was something we should recommend and point our customers towards for more specialised help in this minefield of figures and variables.

To summarise, we highly recommending the CNCCookBook downloadable product for great assistance (it gives you the answer) when calculating feeds and speeds. The CNCCookBook website itself has a lot of free important information regarding general CNC machining including various bits of technical documentation as well as general advice and pointers that is well worth a thorough read for everyone and in particular those new to machining.

Although we do not generally advertise this machine as milling for hard metals, the article clearly shows milling on this material is well within the limits of the machine as long as you get your feeds and speeds correct as well as setting up your CAM operation correctly.

View the full article here

We would like to keep this quite generic to begin with so welcome any suggestions from our customers regarding anything we do. Obviously queries relating to individual customer orders should be directed by email to us.

Please sign up and let us know your suggestions – products? wiki site? let us know!

The Marchant Dice suggestion site is now live here.

We have two units next to each other here in the UK. Unit 6 is on two levels – ground floor is our manufacturing area comprised of a number of lathes, CNC mills etc as well as our assembly and packing areas and the first level is taken up primarily with stock and our offices.

Unit 6 – Manufacturing Unit

Next door we have our training/demonstration room. This has a number of our machines setup inside including a fully enclosed fully equipped version of our 8′ x 4′ rack and pinion. This room is where we can offer our potential customers a demonstration of our machines using both our own materials and any customer samples you may have brought with you. We can also video record and upload to YouTube demonstrations of our machines cutting customer samples upon request. As well as this we also use this room to perform training sessions – get in touch for more information.

Training Unit

As well as these facilities we are working heavily on our online support wiki which is being added to daily. We are covering topics which seem to come up quite often over the phone as well as topics people have requested specifically. Please feel free to contact us to suggest a new topic.

Now to the people that work here…the Marchant Dice team…

	Kevin Marchant – Managing Director kevin.marchant@marchantdice.com
	James Marchant – Operations Manager james.marchant@marchantdice.com
	Martin Palmer – Order Processing admin@marchantdice.com
	Garry Coates – Manufacture/Assembly
	Tim Daw - Manufacture/Assembly
	Cody Marchant - Manufacture/Assembly
	Damian Whitney - Manufacture/Assembly
	Chephren Marchant - Manufacture/Assembly

We hope this has set the record straight. Since our formation nearly 10 years ago we are still growing and expanding at a fairly rapid rate. We base this on our products and the support and advice we offer to anyone that gets in contact with us.

Many thanks
The Marchant Dice team!

Summary of your business…

The project for which the CNC was purchased centres around prototyping of carbon fibre components for a time trial bicycle I’ve been working on the design of.

Problems faced, reasons for purchasing…

Initially, we did a few fiberglass / resin type moulds which did work, but had very little flexibility.  I’ve been dealing with suppliers in Asia for over two years now, some of them very good to deal with, however the ability to produce a prototype or a mould in-house became a major consideration. Although the Asian suppliers were responsive, there was still 10 days shipping back and forth and despite having video conferencing and all the technologies available to us, we still weren’t able to ‘tweak’ as we went along.  Now, with the CNC in-house, we can simply fixture some tooling board, and produce a prototype part, or mould in house within the same day. This has proven invaluable to us.

We do run all our designs and proposed revisions through our suite of FEA and CFD tools to ensure we’re keeping the strength/rigidity we want whilst at the same time, remaining as aerodynamic as possible (as well as staying compliant with the governing body rulings regarding frame dimensions.). To now take that process, and in an hour or two, churn out a mould / plug so that we can lay carbon cloth, all in the same day.. is huge for us. We’ve been able to recover the time windows which had been previously lost to transportation/scheduling issues with the Asian suppliers.

Why Marchant Dice…

Originally, I’d been looking on eBay for a used CNC, my thinking being that we’d find something inexpensive but serviceable, and go from there.  During the eBay searches, I found Marchant Dice and started looking a bit further into having a machine made to my specifications. Many bench top machines have significantly less Z-axis travel than the 200mm I have now  – the ability to specify such things and have the machine made around my requirements was a BIG plus.  Also, the fact that Marchant Dice has a full supply of all the service parts and componentry stocked locally, was a major consideration. There’s nothing worse than getting a machine up and running, scheduling production for it, then having a minor component failure set you back for 30 days whilst your vendor chases a part which has been back-ordered by the factory.

The buying process…

As I wasn’t going to be concentrating on sign making or similar activities, which seemed to be the core demographic for Marchant Dice, I decided to write an email directly to Marchant Dice, outlining precisely what I wanted to do, the materials I wanted to be able to cut comfortably, and the overall size I wanted.  They were helpful, put together a quote for me which yielded an ideal machine, and an overall package which has since worked well. Although I’ve got plenty of computer hardware around, I decided to get a complete package with a dedicated controller PC to run the Mach 3 software on. I figured at that point I’d at least have a single point of contact for all things directly related to the CNC.

Using the machine/the experience so far…

I’d had quite a bit of experience using a Haas VF3 and a VERY large Tarus CNC in the past. The Haas I’d spent the most time on and I had a real ‘feel for it’. The transition however, from a 12-14 tonne machine with a 20hp spindle, down to one which is bench top with a Kress 1050 is HUGE. That’s been a massive learning curve, just getting my head around the way the machine needs to be treated to give me the cutting results I want. It wasn’t difficult per se, but a few weeks just feeding the machine different materials and trying out a variety of cutters was very much time well spent. I now have a fair understanding of what it is and isn’t capable of, and have modified my long-standing cutting strategies to suit. I do recommend to anyone buying one of these machines to just spend a week or two, feed it wood, feed aluminium, feed it tooling board, and play with different cutters and cutting strategies – the experience you’ll have, and the knowledge you’ll gain by doing so will all justify itself the first time you go to cut a component which matters, and it comes out flawlessly the first time.

The installation process itself was painless and professionally carried out by Marchant Dice, the training, although minimal, did include everything needed to run the controller PC. I do, however, recommend any new user giving the Mach 3 guide a quick read, just to touch on some of the fundamentals of the software.  It’s not complicated software to use, but if you’ve not spent time on it before, it’s not immediately obvious where everything is, or what’s the most efficient way to do ‘X’ . A quick read through the user guide answers all.

CNC Machine Setup

The impact on your company…

At this point we’re in the final refinement stages of the design process, so I cannot give any ‘my sales increased by X’ statements. I can say, however, that now being able to cut my own moulds and componentry here has allowed me to ‘hold in my hand’ some of the componentry which will make up the bicycle and has brought to light some issues which would have come up later  (and at a much more expensive stage) in the manufacturing process. I’ve already tweaked two mould cavity designs, and moved a parting line away from where the software had suggested it be, based solely on having had the ability to create the moulds and plugs here, and see how they will perform when laying up carbon fibre.  The week to 10 days (not to mention shipping costs) of having prototype components go back and forth to Asia have been eliminated, and a process for a small stem, which had taken 22 days previously going back and forth with Taiwan,  has now taken a matter of hours to have a prototype (made of tooling board) in hand. This allowed me to test fit for interference against other componentry and make some small design changes which hadn’t appeared necessary when checking everything in CAD.  These types of situations are difficult to put a fixed price on, however cumulatively they make all the difference as to whether a project is profitable or a money-pit.

CAD/CAM of Mould	Finished Mould	Mould Plug

Future plans…

The machine is more flexible than I thought it might be, and now having procured a couple of different pieces of CAM software to allow me to play with cutting strategies, I’ve got a myriad of projects which will be seeing cutting time. Everything from an aluminium stamp for a friend’s business, to a custom guitar body for someone who wants to make his own, and even a few small moulds for a well respected jeweller, from which jewellery will be cast. These are side projects, for entertainment value more than anything else, but they all serve to keep the machine cutting and paying for itself as quickly as possible.  It’s quite likely that in the next 18 months, I’ll buy another machine, with a slightly different configuration, and use that one specifically for cutting my aluminium bracketry, whilst keeping this one for tooling board.

Anything else you’d like to add…

I’ve had the machine just over a month now, and at least half of that has been spent procuring more tooling and just experimenting with the cutting characteristics and such, however what I have done, creating a few prototypes from tooling board, and now having successfully made mould plugs and cavities .. I’m already seeing huge return on the machine, simply from the recovery of previously lost time. I’ve also been able to test fit, and mock up a few assemblies which have resulted in my making changes to component shapes or dimensions – the ability to catch these things, this early in the design process is huge and cannot be under-estimated.

I think design companies should perhaps take a more serious look at getting benchtop sized CNC machines in-house. Yes, 3D printers are cute, and somewhat useful for prototyping, however they’re not indicative of the processes as they will work in any scale of production.  A CNC of this size and similar has such a myriad of uses, and flexibility for materials which can be cut, into anything that fits within the working envelope of the machine, that it’d not be going too far to say that they should really be considered a fundamental part of the design/refine process.

Customer blog: http://anotherdooratthe.endoftheinternet.org

We are using the latest software to make it easier to publish our latest news and industry related information quickly and collect your comments.

This upgrade follows the release six months ago of our new improved online shop – www.worldofcnc.com

Planned upgrades for the near future are the replacement of the forum for a new wiki style set of instructions for our products as well as how to guides to replace the current www.cncmachinesetup.com