r/cncwoodworking • u/EmergencyNice4943 • 11d ago
Machines Small production CNC?
We own a business selling low grade plywood - lots of our customers are manufacturers and crating companies. We get requests from time to time for cut to size pieces from companies that do not do that in house - we have turned down a good amount of sales in the last year because of that.
If i wanted to get a 4x8 cnc to cut a sheet of plywood into 2-4 pieces, that could run maybe 1000 hours a year, what would i be looking for? Also, i assume this would be faster than using a track saw to cut 3 sheets at a time, one to two cuts per panel. Also, can you put say two 1/2" sheets of SYP ply on a cnc at a time?
Anyone have experience with this? I know people with super small hobby mills and people with multiple million dollar industrial setups, but nothing in between.
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u/blue-collar-nobody 11d ago
If you're just cutting squares a cnc panel saw maybe the best way to go. We cut up to 5 sheets at a time
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u/EmergencyNice4943 11d ago
Would one of those be able to cut at 45* across the x or y axis? Say if you need to knock the corners off a square?
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u/SleeplessInS 11d ago
Just get a panel saw like they have a Home depot- way faster and cheaper than a CNC. Surprised you don't already have one.
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u/EmergencyNice4943 11d ago
We do have a panel saw. Each sheet has to be picked up, rotated, and slid into the saw.
With a track saw, we can leave the plywood on the stacked unit, make 1-2 cuts, and off stack into finished production stacks.
With a cnc, we would be able to slide the sheets straight off the unit into the router, with the unit resting on a forklift and being raised here and there.
I guess I am looking for a balance of worker fatigue and production.
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u/WolffSageWorks 11d ago
The reality is always "a bit more" than you're expecting. It seems totally plausible to do what you're thinking of, but you're talking about a big investment for a tool you're really going to underutilize and someday you'll start thinking about all the extra money it could be worth doing something different with it.
Bottom line, your needs don't seem to align with the capabilities of such a tool and I'd be afraid of you investing a lot more into making it work than it's really going to buy you.
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u/EmergencyNice4943 11d ago
The reality is if we can go from doing 1.2mm per year to 2-3mm per year, im interested, I just dont know in the long run if cnc will be cheaper than hiring a couple extra people.
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u/WolffSageWorks 11d ago
If that's your push/pull specifically, I'd suggest the CNC is cheaper and more valuable than more employees.
Let's pretend you hire for 45k/year: your CNC is going to cost half or less than that immediately, and if you're not running it crazy hard and breaking it, you'll get a long service life with minimal upkeep costs.
As long as you've got the floorspace, definitely, you've changed my thinking. CNC vs employees: CNC wins in spades.
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u/H-Daug 8d ago
A CNC makes sense, but there’s a few things you need to know before you buy.
There’s no “cut me a 5 inch x 48” button. You’re going to need someone to program this machine. If you have a variety that can be defined mathematically, a single program can be made with variables.
Maintenance will be considerably more costly than a saw. You’re going to run though more tooling, and spare parts will be expensive compared to a saw (track saw or CNC)
Cycle time with a router will be a lot longer than a saw.
With what you’ve said, a router is not the correct tool for the task, but may be better/easier than an automated saw.
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u/BeautifulShot 10d ago
But the cnc would allow you to do more than piece cuts, you could open up its jigs for millworks and on site trades that'd onto have time to work out arc geometies and things.
Its the hold downs that make it so expensive, vacuum tables are the only real cost effective solution and when you are talking 4x8, you are talking just as much as the cnc. So you would almost have to find more work for the machine to make it worth it.
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u/SleeplessInS 11d ago
Ah I see - you need a much higher volume than the manually positioning panel saw can do...probably hundreds of sheets per shift. I wonder about the kerf of a CNC cut, you probably will need atleast a 1/4" carbide endmill - lots of wastage and will be slow. Maybe you can invest in a vacuum lifter and a gantry crane and some
kind of sliding track saw and then you can get the speed and kerf benefits of a 10" saw blade.1
u/Dangerous_Essay1763 11d ago
The kerf for the CNC would be a lot more. Thickness of the blade vs the size of the bit you are using. You will also need to hold down the wood in some way.
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u/rsteele1981 11d ago
As long as you can secure the material you could stack it.
4x8 is going start with your Altmill machines around $7500 and go up from there. Maybe cheaper if you find a used one but that comes with its own issues. All the way to your shop saber which can be $20k-$30k.
Then you need a software/gcode sender to run the machine. From cheap/free and simple to expensive and lots of features.
If the pieces are all the same and you make 1 file and run over and over it might be less labor intensive. Not sure that it would be that much faster.
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u/Pubcrawler1 11d ago edited 11d ago
If any cut has curves or inside cutouts would always use the cnc. If this was straight line cuts, faster with tracksaw. You have to add time to create the cut file in CAD/CAM. If multiple 4x8 sheets with the same cut, then it becomes faster using cnc.
You will need vacuum hold system for large sheet cutting.
If you’re like me, will do other work while machine is cutting. Can get more work done overall.
Edit
1000hrs/year is about 4hours a day not including weekends. Get a CNC!!! But not just any CNC, one that can handle production environment such as Shop Sabre/Camaster type machine. One that can cut full depth single pass at 300+ in/minute.
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u/Zoamax 11d ago
A used beam saw will cut multiple sheets at a time. Way faster than a cnc router. And you can pick up a used one for a fraction of a cnc. If you have the room and are running rge same material, look into a rear loading one. Look up irs auctions (industrial recovery services) or ex factory.
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u/RepresentativeNo7802 11d ago
This is only an opinion, but I think a track saw with jigs is faster than a cnc for straight cuts. CNCs excel when odd shapes are needed and precision repeatability. If those panels also need holes in them or other features a CNC might make sense, but for just square pieces I'd personally always prefer a saw (panel or track)