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View Full Version : What CNC Router and Extraction will suit my needs?



flightcase01
15-03-2011, 02:21 PM
The company I work for is looking at buying a CNC Router and the correct extraction to suit.
It needs to be able to take 8' x 4' sheets of plywood 6-18mm thick. It also needs to be able to cut these sheets into smaller pieces of all different sizes.
Tha machine then needs to be able cut holes out of these pieces and drill holes around these cutouts.

My colleague has been to look at a few different size machines ranging from 15-50k setups but these are people trying to sell them to us so they are all saying theres is the one we need.

Some inpartial advice would be much appreciated.

Thanks

M250cnc
16-03-2011, 04:20 PM
Best advice would be to google the names of the manufactures with "problems" as search words

Phil

flightcase01
16-03-2011, 06:16 PM
Thanks for the reply, but I could do with someone telling me where to start looking (i.e this machine can do that job, the make is..........and a good extraction for this machine is....... )
Like I said i have never used one of these machines before and our company is making a bit of a gamble buying one and doesnt want to spend 30k on a machine that doesnt do the job or finding out later we could of spent 20k on one that does what we need.

Its just a starting place I need please.

Once again thank you for your time.

M250cnc
16-03-2011, 06:42 PM
Well only you know the names of the machines you are looking at. :wink:

So just google search "Machine Name problems" you could also search for "Machine Name review" when your spending a lot of money its worth the time to do the research.

Phil

Dairsie
26-08-2011, 11:19 PM
Need more info on machinery you are looking at, the pods are the way to go for smaller work pieces, as for extraction this is dependant on your exhaust pipe requirement and is differing from each machine. It must match to have any hope of sucking up residue like MDF. I do not see any special needs other than you must have the capacity to supply to the new machine and it is in the correct flow of your overall system to get extraction where it is needed (extraction goes from large to small basically as regards ducting and should be flowed accordingly and planned by your extraction company when they deign the system. I have always found I reconfigure my extraction every two years or when new machinery is fitted, the floor plan is more to do with what I am replacing and it has air/power/extraction capacity in position.

I did invest a few years back in straightening my flow between my shops to generate extraction more eficiently, I had three motors feeding the three shops, I also added auto dampers so my system can run on 10% power capacity normal (stops implosion of ducts) and only switch on more extraction when and which machine needs it. I saved a good amount on power accordingly and it will repay itself shortly for the 30k I invested to improve flow dynamics, I used DCS Ltd from Leeds, speak to Melvin.

I like the Homag currently and I am currently tendering up a replacement for my old CMS Giotto 11 year old now so can be open to see what is offered, had a four head Reichenbacher 15 year old, good kit for time but pricey, first machine we bought very restricted in memory and use first DOS I had/CMS was second DOS. SCM/Homag can do entry machines for less than 50k, they wanted me to buy this in January I went for a CNC multi Drill by Masterwood for panel drilling/routering far cheaper and suited what we were wanting, did not have floor space for a fully blown Router. But I have been in contact with four companies and hope to have them visiting in the next few weeks to discuss my needs. Then its VFM and tech spec I will go on against best for cost. The market is very much customer sided due to downturns in markets.

Jonathan
26-08-2011, 11:59 PM
(extraction goes from large to small basically as regards ducting and should be flowed accordingly and planned by your extraction company when they deign the system.

That's not true ... if you want to get a good a vacuum as you can at each outlet you should not progressively reduce the size of the pipes. The flow resistance of a smaller pipe is greater, so the pressure difference at the end will not be as great. Think of each pipe as a resistor - doesn't make any sense to put a bigger resistor at the end.

I wouldn't use anything less than 6" diameter.

Web Goblin
27-08-2011, 09:04 AM
Jonathan,
I think what he means is starting at the extraction unit he would have say a 300mm dia duct which would then plit and reduce down to three or four 150mm or 100mm dia ducts going to three or four seperate machines rather than a single duct reducing down in size.

Ian

Jonathan
27-08-2011, 11:19 AM
Jonathan,
I think what he means is starting at the extraction unit he would have say a 300mm dia duct which would then plit and reduce down to three or four 150mm or 100mm dia ducts going to three or four seperate machines rather than a single duct reducing down in size.

Ian

Yes, that's what you shouldn't ideally do. If you think of each length of duct in that system as a resistor, with the smaller diameter ones having a lower resistance, then it's obvious why...you're adding a high resistance in series instead of a low one, which is just inefficient. If you have several ducts open at a time then it doesn't really apply, but then you're not going to do that in a home workshop...

Dairsie
27-08-2011, 12:00 PM
Jonathan, my system is industrial my lines start are approx 3ft dia from motor to shop ceiling and reduce from there as they feed there dedicated line. My system cannot reduce to extract from portable tools for example.

To be efficient you must start with your lines large enough to meet the needs of the overall capacity of the line and natural drop in the draw as the length increases from the motor. I get a designer in its that simple, to get the flow correct as each auto damper opens and shuts and gets its full draw to meet the need of the machine it feeds. My spindle/CNC Morticer/bandsaw are not fitted with auto dampers and make up the 10% needed to work all the time due to implosion of ductwork if all system stopped drawing. My hand sander tables are fed from the extraction system and the power tools fitted to their own vacumns just like some of my chopsaws in assembly due to my extraction not being able to cope with portables.

MDF dust leak in my Beamsaw and Router is kept to minimum accordingly due to it being designed to operate efficiently. Extraction cannot be 100% due to saw draft or dust spitting out machined opening but you try to keep it down with ceiling intakes clearing the atmosphere and removing any fine dust. Some CNC Router now have a catch belt below the cutting table to catch spit/dropping residue from cutter and the belt conveyors it to a waiting pickup pipe at end of machine. The saw draft residue on my Resaw for example drops to floor or sits on machine table for vacumning. I do not have dust problems with my Optimiser saw as it it is in its own cabinet. I do have a Crosscut and have tried a few combinations to try catch the saw draft, but as it extends to do wider cuts is the problem and the suction drops from the catch can at the rear of saw.

I test my air/extraction every 14 months max for COSHH and legaility of UK H&S requirements. The personel dust monitors on workshop staff has proven itself to keep the dust air born to well near as enough not detectable. I have visited and worked in other shops where dust could be waist deep and the air thick with pollution. Cutting some woods you can be coughing or eyes watering especially with some of the hardwoods, you cannot do that in a factory not if you do not want litigation, plus it just looks poor.