Question
I am considering building closets and some frameless laminate cabinets and am wondering, since starting from scratch, should I shop for a small machining center with a table or vertical panel saw and edgebander? Or a full blown nested router and edgebander, or just a table saw, boring machine and edgebander?
Budget is of medium concern, the market is there, labor in our area is reasonably inexpensive (burdened cost at 18.53/hr.), but not necessarily the best of craftsmen. Space is of no concern; quality, reliability, and some speed is more of a concern.
Forum Responses
(Business and Management Forum)
From contributor B:
Nested CNC, no question, based on your answers.
Nested base CNC (with software of course) requires you to put the sheet on the table, push the button, then run parts through the edge bander. Custom changes are no problem. Your manufacturing process becomes zip.
Closets are the easiest thing to manufacturer because everything is drilled from the face and uses RTA fittings. There are no dadoes, staples or glue. Parts off the CNC are perfect and don't require fussing with. No one reads a tape measure and everything is exact size. Two parallel lines of holes are not going to cut it for closets. To make them work, you are going to need holes in other places. With a CNC, you can have anything you want. Vertical saw and line drill requires a whole lot of work as compared to a CNC. Spend your time growing your drill pattern instead of outgrowing your vertical saw and line drill.
Now I have a bigger shop (7000 sqft) and a lot more employees. I could never work this fast if I was still using nested based manufacturing. The combination of panel saw, edgebander and two of three good boring machines is very fast. But it takes a lot of good employees to make it work and more importantly, it takes a good production system to organize the work flow. These things can only be done if you have a lot of experience.
Do you have a real business plan? Something that is more than 20 pages long and has projected cash flow, operating costs and gross sales projections? This is really where you will find the answer to your question.
If you intend to gross 10K a month for the last 6 months of the first year, do not get the CNC. If you think you will be able to gross closer to 20K, you will need the CNC simply to make up for the lack of shop experience. 20K is easy to do in a traditional shop with manual machines, but it requires very skilled people to do it. 20K will only barely give you an ROI on that CNC machine. If you are looking towards 100k plus a month you will probably be looking at more of a hybrid production shop with panel or beam saw, CNC machining center (not NBM) and automatic doweling equipment.
We are able to squeeze out 60K in a month using a manual slider, nice edgebander, and three manual boring machines. My staff is still new and we struggle with lots of mistakes and lost time. I have 7 employees now. This is month 6 of production.
One thing that surprised the heck out of me is how much we run the edgebander. My shop before was all face frames and did not need a bander. Now we mostly make frameless cabinets, furniture and closets. The bander runs all day, nonstop most days. Sometimes we have to wait on the bander even if it is running at max speed (20 meters per minute I think). If she breaks, we are totally screwed! My advice is, if you will be making a lot of banded products, buy a good machine. Brand new and industrial duty.
I have completely changed my tune on this one. I can make better cabinetry - faster - thus lowering the customer's costs a little bit. The CNC enables you to create all the joinery, special cuts and milling operations and talk the customer into personalizing their project by offering them wood carvings (hand carve, big dollars; CNC carved, smaller dollars). So now you can step up the personalization for the customer and make it very affordable for them.
After I got my CNC and had it cut a kitchen for me, my only regret was I hadn't gone that route many years earlier. On top of a lot more accuracy and higher quality, it really helps to save the back if you come up with a nice cart that can hold your plywood and just slide it from there to the CNC table.
If you can swing the CNC route, do it! You won't look back.
I have to say thanks for all your many detailed posts and helping me/others think productively!
I have two boring machines in production now. They are both construction boring machines, but I wish I had bought one two head line boring and a construction machine. I do not have a CNC boring machine, yet. We have gotten things to go pretty fast with the manual machines.
There are two keys to making these machines fast. First, proper engineering of the cabinets, having all the hardware holes fall on 32mm increments and all the same offset from the bottom. The second is having good documentation of the patterns so it is easy to set up the machine. The CNC machine will also benefit from this kind of engineering because the spindles are on a 32mm pitch, allowing the CNC to consolidate operations.
We have one machine only for doweling; the other is used for line boring and stretchers or partitions that cannot be reached on the dowelling machine. I will say that it is very hard to get these machines to be so productive. It has meant a lot of stressful days and long nights.
Here are some pictures of the boring machine we use for line boring and a PDF of our boring pattern sheets. Notice all the boring holes align to 32mm increments. The numbers on the right side represent the drill spindle to be used, the left side is the actual measurement. This eliminates all the guess work. This is an old version and not all the holes line up correctly. It has taken me months to get Cabinet Vision to play along with my engineering scheme. Also I have added the setback dimensions from the front as well as some other details. With this document even my least experienced employee can drill a complicated cabinet like this one in 10 minutes. This is a closet cabinet that has two rollouts mounted in partitions to create the hinge clearance. There is also a face view drawing that tells the operator the partition inset values and other items.
I would like to add a two head line boring machine, but now it seems too late. I really want to get the CNC machine ASAP. I strongly believe this type of CNC is the future of small shop production. They are not expensive, use little electricity, and do not require the complex systems like massive dust collection and vacuum systems. They are actually a lot faster than the oversized pod and rail or nested type machines. Part handling is simplified as well.
The nested solution driven from the office via software. You land the job, draw it as detailed as possible, send it in for approval, make corrections, order the material and press optimize, send the info to the router, cut, drill, and send to the bander and assemble.
I am speaking from experience. At this point in time we cut on a slider, groove for backs on a table saw with power feed, band and then bore on a ptp or machining center. We are fast, and I mean fast, but that is only when the top employee is on, not hungover or sick or having love problems. Yeah, he can be a damn constraint - so my next acquisition is the nested router, and it doesn't get moody.
Look at the router, used bander that has had an inspection from a tech, and a construction borer for horizontal drilling.
10 years ago a feed through line boring machine looked like the first two images. They are basically manual boring machines with a lot of heads that can pivot and slide. Once set up, they can process up to 150 parts per hour (with feeder and stacker). These machines are still the cheapest and fastest way to make a lot of parts really fast. Ikea and other big panelized furniture factories rely on these machines. They can take 10 minutes to set up, but then they will crank out parts at a blistering pace with perfect accuracy and using a fraction of the electricity a CNC does. A CNC feed through boring machine can refer to one of these beasts that is fitted with NC servos to position all the heads and auto select the cycling of them. But the bits are still manually set in the heads because the bits are not independently operable. These machines are meant for part batching and are not appropriate for the small or larger custom shop. But they cost less than a CNC and can be a lot faster when paired with a beam saw.
The modern version of these machines, which are sometimes referred to as a feed through CNC machining center, are a lot smaller and more versatile. They look like the last picture I uploaded. There are some great Youtube videos showing their operation as well. The machines by Gannomat, Vitap, and Griggio are oriented to smaller shops. They have small footprints and do not require more than an electrical connection and some air. Beisse and SCM make bigger machines that bore both sides and run a lot faster, but take up a lot more space and require part feeders and stackers to run efficiently. They also cost much more.
All of these machines are capable of light duty part shaping, grooving, and all kinds of boring, including end boring.
What kinds of employee mistakes do you see today that going nested will solve? Do you use barcodes on the PTP? Do they make errors on the banding? Seems that the only real problem area for you should be the cutting.
I am asking because our setups sound similar and I also am plagued with remakes, but I have a new shop full of new employees, so I feel like it is due to the learning curve of my employees and the continuing development of my own production process.
Some of the mistakes I see are the forgotten to be cut adjustables or stretchers. And I see them on the damned cut sheets, because I generate them and do the math to make sure they are right.
The errors on the bander are rare. I would love barcode on the PTP, but the people that sold me the PTP always duck and run and say it would be a lot of work to install it. They lost all future sales. Biesse wants enough for a hefty down on a router table.
Yeah, I agree on the barcode CNC boring and I'm pricing it in the am. I read about them 6 months ago in a trade magazine.
We don't have the room for a beam saw, nor do we run that much, yet. It's in our long term future. I used to buy my countertop blanks from a guy that ran them on a flat table for me and I plan on using it for that also.
Do you remember your first 20k frameless job? Quite the anxiety, eh? Well, it's become routine for us and I'm ready to step it up. I'm 44 and my best employee is 53. He never misses work and is reliable, but can't cut fast enough to appease me, but my second best can cut like I want, but when he's on, he's on, and when he's not, well...
I just see nested as what it is. If 40-60 sheets a day is doable, then it's worth a lot more for us by the end of the day. It cuts the complete job, nailers, decks, everything. The saw operators can get sloppy after 6 hours. The CNC operator can band and horizontal bore, run the Castle machine and tap dowels.
Another issue with CNC is banana cuts. If you are cutting particleboard, you know by now that banana cuts are a part of life. The way nested CNC works, there is no fix for it. I think the vacuum would have to be turned off to allow the parts to de-stress, then kick in and all parts trimmed. I am not sure what the solution is really. I do know that in my shop almost every non-flush assembled part is due to freaking banana cuts. I have instituted strict stress cutting procedures on the saw. This takes little time on the saw, but it would add a lot of time on the CNC.
Are you sure stretchers are not getting lost in the shuffle? I have had them used as scrap to set up machines many times. We preprint our part labels (no bar code). The labels are grouped per sheet and in the same order as the parts would be cut out of the sheet. Having the labels on the saw means that the operator cannot forget a part... There would be an extra label if he did.
Contributor C, be warned that the CNC will produce 50 sheets of parts a day. Can the rest of the shop keep pace? Our machine sits more than it runs, yet when it runs, it out-produces our old slider/boring machine setup by miles. We had to purchase a case clamp about 6 months in and now face a major log jam at our finishing booth.
The ability to rough draw a job in CabinetVision for quoting and then with the click of a few buttons be cutting is amazing.
How long does it take for you to cut a sheet of material? Assuming 15 minutes plus time for boring and grooving, a CNC takes about 10 to 15 minutes a sheet with boring and grooving done. What am I missing?
Contributor P, first of all, a shop's production strategy depends on the product. Keep in mind that I am focused on melamine case work, no face frames.
What you are missing is that these processes are happening simultaneously. Just as with the CNC, parts are being cut, bored, and grooved at the same time, just on separate machines. Once you have a good flow going, the parts end up in the assembly area just as fast, sometimes faster.
As many point out when you have a good setup (be it NBM or saw/boring solution), assembly becomes the issue. At full tilt I need 2 or 3 times more assemblers than machine operators! Imagine 4 operators and 10 assemblers. That is what it takes to balance my production. (I still do not have that many employees, so we practice the Lean flow method of moving people to relieve the bottlenecks in real time). So I will happily sacrifice operation time to save assembly time. Also going to a very costly NBM solution would not help my product flow at all. Assembly is still the bulk of our work. I would still need a banding operator, dowel machine operator, and a CNC operator. That is only a reduction of one employee out of 10 or 15. Factor in the huge cost of a nesting CNC and the higher operating costs/maintenance and it starts to not look like that great of a solution.
Other issues with nesting are dealing with panels that have stress (banana cuts), tooling selection, keeping tooling in sync with the software, and redundancy. By redundancy I mean that you will still need a saw, and provisions for grooving odd parts, and a boring machine for dowels (unless you go with dados, which slows assembly).
Advantages of NBM. It is entirely possible for a single man to have a productive shop with only a CNC machine and some clamps. Also, I think that a new-to-the-industry shop owner will benefit from screen to machine because they need not learn the thousands of little details like setting scoring blades, dado heads, aligning saws, preplanning boring patterns, logical cabinet layout and all that stuff. For larger shops with more than 2 or 3 employees a lot of mistakes can be eliminated. There are also lots of sideline opportunities for the CNC such as sign making, plastics, modeling, prototyping, etc.
Many of my statements can be countered by other shop owners who have different experiences. In my experience very few American shops are as efficient with their traditional shops as they could be. Going to NBM gives these shops a massive production boost because they were not really doing that great with what they had. If you have spent much time in the business, you will have seen by now what I am talking about - crowded dusty shops doing things the same way they did them 50 years ago, but with new machines. Piles of clamps, operators that are not following any kind of system at all. As long as they get the job done, the owner doesn't change anything. A Lean manufacturing guru would have a heart attack if he went to these shops. I am not a Lean guru, but I read the book (he he he).
I have spent time in small German shops where three guys and the basic compliment of euro type machines (slider, bander, single line construction borer) are able to crank out a good sized kitchen in a day. Their shops are very organized and there is no unnecessary work being done. If you do not believe what I am saying is true, talk to the industry gurus. Look around at why China is able to send cabinets here cheaper than they can be made locally. It is not the reasons people usually give. Finally, look at the economics of our industry. There is no other industry with the high markups, high margins, but low profits we enjoy. But as businessmen are able to penetrate the industry, this will change. Screen to machine is helping that happen. Now a MBA grad can buy a CNC, rent a shop, and follow the advice of the various machine and software reps and make cabinets as well as any of us old timers.
Most shops will have the CNC operator doing another function besides running the CNC like edge banding. Going along with the Lean thing, you have more WIP - in fact, way more WIP.
Your ratio of assemblers seems excessive? Since the cost of a CNC machine is about what a cheap employee would cost, it really is not an expensive investment. In your neck of the woods, maybe employees are cheaper - this may influence your thinking?
Our setup is a lot like yours, and very fast, but the PTP or machining center allows us to save time in the area of material handling, and all drilling could be done in one place. What we have timed out was that it was quicker to power feed the back grooves/dado on the tablesaw than waiting on the PTP to route and then drill the same end.
I just see the CNC router cutting, drilling and plowing for a back in one place and that is a huge savings in time. I also see the software doing the same for me.
In the same 10 minutes, our CNC operator working in his cell will load a sheet, edge parts from the previous sheet, and end bore if we are dowelling. The parts from the CNC are ready for assembly... Case clamp is a must.
There is more to it than just the cabinet. We cut doors (slab and MDF) that are pre-drilled for hinges, handles and bumpers. Our software will grain match and still nest cab parts around the matched doors. We cut access holes, grommet holes, notch shelves for wire access, etc. By engineering every job up front, we have eliminated as many secondary processes as possible... some still get by.
Optimizing is the final step up. Ignore that nesting on a router yields better returns than a saw, especially if you are cutting shaped parts. It is hard for a slider operator to handle 5x10 sheets all day by himself and keep the sheet tight on the table for clean cuts. We optimize out of sheets larger than 4x8 whenever possible. We get good yield and even less raw sheet handling time.
I could ramble on but we came from a well thought out slider, bander, boring system and it always had its limitations. With the nested solution, even Friday afternoons have become productive.
Here is another way to think about this. Before a given sheet is finished being cut on the saw, the first parts from that sheet are already banded and grooved! By the time the saw operator loads the next sheet, those parts are being bored. Before the saw operator is done with the second sheet, the parts from the first sheet are being assembled! This is not really due to speed; my operators are not that fast, yet. If I had good experienced American workers, I would be doing a lot better. It is due to the process that allows parts to flow through the production process with the least resistance, as someone else mentioned earlier in the thread. In every case a part is immediately processed after the previous process and there is no distance to cover. Most of the time the "outbox" of a process is the "inbox" of the next process.
So while your nested sheet is still cutting its first sheet, we are already banding the parts that are still on the CNC's table; while you are labeling the previous sheets parts (or the next sheet if you use the Carter laser cut pattern projector), our parts are being bored. When you start edgebanding your first sheet, we might already be assembling that same cabinet.
My man hour per cabinet for a typical kitchen base cabinet with a door and drawer is in the area of 30 minutes process time and 20 minutes to assemble, adjust, apply corner protectors, stretch wrap and move to the pickup area. For a tall closet with 3 rollouts and two full-height doors, it is around 50 minutes process time and 30 minutes assembly/packaging.
These numbers are pretty okay for a shop like mine, but the magic is that the man hours for processing and the total elapsed time from cutting to the start of assembly are nearly the same. In other words, you can see the parts for a cabinet get cut, banded, grooved and bored in less than 30 minutes. Parts are never shuffled, re-batched or left in piles. That is what Lean is about. Lean is not about reducing labor; it is about reducing non-value added work, in increasing TAKT. (Technically TAKT is supposed to drive production in the pull of orders, but if you are already at capacity and the demand outpaces your TAKT you need to focus on improving the TAKT).
My system only flows this well 20% of the time. I started strictly following my production scheme 2 months ago (it took me three months to get my employees trained well enough to handle the throughput). In the last two months we have made many changes. I have completely reengineered my construction methods, twice. Wrote several horribly complicated UCSs for Cabinet Vision, reworked my shop drawings (I am now finishing up the third version). Added work benches, re-plumbed dust collection. Moved the grooving station twice, and shuffled the work flows of individual processes more than once. Most of these changes resulted in improvement, some did not. I feel like we are about 70% there with my current staffing levels. Most of the big improvements have come from me generating better paperwork for the shop, and implementing more engineering standards.
A big engineering standard that speeds up boring a lot is that all face boring operations are on a 32mm grid. This includes stretchers, nailers, hinges, guides, fixed shelves, closet rods, every single thing. The fences on the boring machines are all marked for 32mm spacing, and we have a couple of tricks to very quickly set up the boring machines.
My point is this was not easy. I have been relentless in making these parts flow as fast as possible through production using the resources at my disposal.
In production it is the boring processes that eat the most of my time. A CNC boring machine will make a huge difference. In assembly, a dowel drill/insert machine would knock off 5 minutes on average. We still pound dowels with a rubber mallet. A case clamp will also help, but I do not think it is a big deal right now.
My labor costs are very low. I am located in SE Asia. I sell in the local market and all my competitors have the same labor costs as me. Actually I pay my people a lot more than my competitors. This makes a difference in my bottom line and in my decisions about upgrading machines. For example as we get better at the boring machines I do not see the need to buy the CNC boring machine. I can have two operators doing that. But the numbers I am giving you regarding NBM CNC vs. part flowing on a saw/boring machine apply either way. I do not think a shop can process 40 or 50 panels with less than 3 people in production (forget about assembly). You are still looking at the same number of employees, but a much higher investment in machinery and higher overhead.
This is why a lot of two man CNC shops start losing money when they hire more people to increase capacity. The CNC quickly becomes the bottleneck. I have seen many shops (in the US) combat this problem by running all parts with face boring on a nested CNC and all parts with no face boring on the slider or beam saw. Then all edge boring is done on a dowel insert machine. This is what I was referring to when I mentioned the hybrid NBM/saw and bore solution. I have heard a lot of smart machine reps talk about this setup as well. But the logistics get really complicated when you try to flow out single assemblies in this type of production. Trying to keep the part flow balanced is confusing so shops usually resort to stacking and sorting parts in racks for the assemblers to pull from. There is cutting edge technology that uses RFID in real time to monitor the current status of the assembly flow to indicate to the saw operator weather to cut drawer box, cabinet back, or case materials based on what the NBM machine has already put into the part stream. This way assemblers will have the right mix of parts to complete assemblies as their parts are completed. I do not know of any successful implementations of this tech but it is surprisingly applicable to the smaller or medium sized shop, because it allows a small shop to maximize their resources in a way that a big shop could never do.
How was that for a giant load of BS? I should become a salesman for systems integration solutions.
Also, as I said previously, my parts are never sitting around waiting. The parts are being banded and bored before the sheet is finished being cut! You know better than that.
My saw operator takes about 13 minutes to cut an average 18mm sheet with case parts, backs, doors and drawer parts go faster. The overall average is in the 10 minute neighborhood. When I say average, I mean at the end of the shift I divide the number of sheets cut by the number of hours he worked. So this average includes fiddling with the scoring blade or using the bathroom.
I had a budget of 150 K to start my new shop! That was enough to get the saw, 2 boring machines, planer, jointer, bandsaw, two dust collectors, and a very good edgebander. This also included money for fitting the shop out and operating expenses. A CNC was not possible. It is still not. In fact I can not imagine why I would drop 200K on a good Beisse Rover in the next two years. With my current setup I should be able to crank out 100,000 dollars a month gross with no issues. The profit margins will be nice. A CNC will not change my gross, but it will severely impact my bank account and overhead. There is a point at which running a CNC will become an advantage; I am not really sure when that is though. I will need the CNC boring machine first. It is only 30 to 60 K installed.
The average new shop can suffer under the weight of a CNC machine. But a one or two man shop with a NBM solution can make a lot of money. If I was in the US I would still be doing that now. Not because of labor costs, but because the stress in the US is a lot higher for a larger operation.
I think I agree with all that you said, contributor O. I would love to use 5x10 sheets. But as you said, we can't on a slider. I am imagining a rear loading beam saw when I get to that point. If I get there.
Taking this a step further, when the inevitable mistakes pop up, they are immediately fixed. No interruption in the WIP or overall assembly flow. There are assembly sheets waiting at the boring machine, so when all the parts for one cabinet show up and they are bored, the assembly sheet and the parts are put in the pull area for the assemblers. The assembly sheet lists all parts, their dimensions, and the banding code. If there is a bad part, the assembler simply highlights the part on the assembly sheet and gives it to the saw operator. No explanation necessary. He cuts the part immediately from scraps or a new sheet. And it goes through the process until it shows back up in the assembly area and that cabinet is finished. WIP perfection.
Well it is not perfect, but no one is more hell bent on improving the process than me.
You say your system only flows to the TAKT of 50 minutes per cabinet about 20% of the time. What happens the other 80% of the time?
When you mention cues, I think you are referring to Lean, Kaban if I remember correctly. The cues are a sheet worth of parts. If the saw/banding in/outbox is full (a sheet or more worth of parts), he moves down stream. At the bander/boring in/out box, it is 2 complete assemblies. At the boring/assembly in/out box it is also two cabinets. If there are no complete assemblies to process in the boring or assembly, then they move upstream. It is the usual work cell arrangement.
My assembly process is actually three separate stations that can be manned by 1 to 6 people. Hardware fixing (before assembly), assembly, packing.
I now have 5 employees; two good, one okay, one not good, and one brand new. It would be the equivalent of three average American workers. It has varied from 3 to 10 over the last few months. I have a couple workers now I want to replace actually. Sometimes I hire temp help in assembly.
It is difficult to say how many cabinets we make in a day. We can make around 15 complicated tall closet cabinets with RTA fittings that are not assembled, but are packed as an RTA product. We can make 20 average kitchen cabinets. Average for us is a little bigger and more complicated than in the states. Cabinets are seldom less than 1000 mm wide and usually have two or three drawers. Not very many simple base cabs with a door. Uppers usually have lift doors, aluminum/glass and other design features. These times include making the laminate doors, drawer boxes and packing it all up.
I say 20% of the time because as I stand back and watch them work, I see points where it breaks down. Edgebanding has been a problem. Workers have a hard time understanding which edge is which, boring is generally a nightmare, assemblers do not work together as I want them to, and workers tend to have to be told by me to change positions.
I have a lot of unique challenges. This is a third world country. My employees have no real education, do not speak English (I speak their language okay) and they had no concept as to what a cabinet should even look like before they worked for me. The idea that perfect really means perfect is tough for them at first. But they are learning fast. Also it depends on what we are making. Kitchens go pretty smooth now, closets are okay, furniture items are a little iffy.
It is easy to keep up to the router with the bander. The 10 minutes per sheet (honestly closer to 12 over a shift) allows for load/unload and labeling. Average number of parts per sheet is only around 12 (4x8). 6 gables per sheet up to maybe 20 smaller parts. I have never time studied the bander (maybe I will tomorrow), but I would guess 12 parts, one edge, no more than 3 minutes max (sounds long). That still leaves time for him to organize parts into cabinets for the assembler. Average cut time is 6-7 min/sheet.
Nested is not the fastest method to make parts or cabinets - agreed. Go to Nobilia.com and watch the video - no nested routers. However, in our custom shop it speeds up the mundane cabinet construction, allowing our cabinetmakers to focus on more complicated parts of jobs. We are not in business to just make melamine cabinets. But to be competitive in my market you need to be efficient at it.
From your posts, even in America you would still need to micromanage your line. Everything in such fine balance is a fragile environment. We can handle rework with the click of a mouse. Being a CV user, you understand that power. Repeatability is unmatched.
Tomorrow we are cutting approximately 10 cabinets, 30- 46" dia rings, and 10 - 4x8 panels with circles cut out of the middle and a company name written across them - approximately 35 sheets, and this will not take all day for one guy. Can your system cut holes, circles and engrave text? This is why we went with a router.
But you are saying that using CNC is not as fast; I don't see this. Your numbers say that you have about 2 man hours per cabinet. The average CNC shop has 1 man hour per cabinet. The medium size shops on these forums have less than 1 hour per cabinet.
I do not intend to micromanage. I rely on accurate reports and standardized processes that eliminate the need. If the employee looks lost, or can't figure out the right way to do something, I assume it is a fault of the process and I work hard to correct it.
When you talk about the versatility of a CNC, that is the main argument for CNC. The CNC does not care about the size, shape, joinery or other details. You draw, it cuts. The few radiused kitchen cabinets we make have standard radiuses (550mm and 300mm) so we have the templates ready to use if needed. But complex shapes take us a lot of time to produce. I could never justify 200K or even 100K on a CNC machine because it can cut circles. That would be a massive loss, even at US hourly rates. But if you are doing that on a daily basis, it is a winner. Also in shops like yours that make small batches of custom millwork parts, it is a winner. This will be the reason I buy a full sized CNC. Custom millwork, complex cabinet parts, sign making and prototyping can be very profitable if you keep the machine busy.
How long it takes us per sheet varies a lot depending on what is being made. Kitchen type parts on 4x8's, about 7 sheets per hour. We run a lot of larger sheets, better optimization, large parts, less time per part. On larger jobs the CAD guys separate the plain rectangular parts and send them to the optimizer, then to a Schelling beam saw. Since we do a fair number of bookstores, there are lots of shelves. These can be stack cut 3 or 4 sheets at a time. The saw cannot outproduce the CNC when single sheet cutting, but it can be used in parallel to increase total throughput. We have a large bander with multiple stations that allow lots of different banding options. Our most common banding is 2mm PVC. I wouldn't want to change banding materials for every few sheets. Typical time for a part through the bander is every 6 or 7 seconds. Feed is 18 meters. Parts are labeled including a graphic of the boring pattern and the edges to be banded. Not necessary in a very small shop.
Since we move all parts via roller conveyors parts are stacked as they come off the machines by next operation. Keeping batch sizes small helps everything but trying to go as small as 3 or 4 sheets would be counterproductive if it involved any machine setup changes. Even if it only takes 2 or 3 minutes to change banding, that's equal to 15 parts being banded. Banding is faster than routing, except for contour banding/trimming. So the bander is started a couple of hours after the router. In a big shop that would be different. The bander operator also runs the bore and insert machine and the contour bander. The boring machine sets up by wanding the bar code on the label. With 3 drills and glue/dowel inserting, the machine can do a wide variety of work but is slower than a dedicated through feed. We can, however, process 8' long parts as well as both face and edge bore for RTA. We case clamp simple boxes. Our shop would be set up differently if we were making kitchens. We are a job shop - lots of variety. I often think too much variety, but it has meant we can stay (sort of) busy when one area falls off the edge.
Work in a typical week can include: parts for a recreations equipment mfg (66 sheets at a time routed or sawn about every 2 weeks), aluminum transitions from 3/16" strips for a flooring company, thermoformed solid surface for a countertop shop, foam core laminated tabletops for basketball officials (about 25/month), short runs of custom moldings (a few hundred feet a day), recently fiberglass and aluminum honeycomb parts for aircraft, store fixtures or parts for another manufacturer, mounting boards for a machine shop, bundle boards 6,000 at a time for a printing co, 3" thick UHMW tool trays CNCed for a railroad shop, a few signs routed. Am I starting to sound like a jack of all but master of none? I don't recommend this sort of mix unless you have some very talented staff.
