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Increasing automation in a small-medium shop7/1
I'm looking for advice on automation. We currently do about 1.2-1.5 million in sales per year, all commercial projects varying from casework to architectural millwork and solid surface work. We're using microvellum 7 for casework and were learning more about it every day. We're cutting parts on a vertical panel saw, we just upgraded our edgebander from a Ott Atlantic from the early 90's to a new scm k600 and we machine on an scm tech 80. The new bander has only been running a few days and it's already making a bigger dent than we thought in the casework jobs. We're still a ways off from buying a new Machine but I'm curious to see what people think.
I've been told our scm tech 80 p2p is old news and nesting is really the way of the future. I don't doubt it but I question the investment. We won't get much for the tech 80 on a trade in and if we go to nesting we still need a means of horizontal boring. Has anyone done nesting then done horizontal boring on a p2p? I know it may be overkill having 2 cnc's in the shop but we have the room and I would rather keep it around than get peanuts for it.
Any feedback on this would be really helpful and any other advice for ramping up production would be much appreciated.
You could do that, but most shops in your size range find that dedicated horizontal drilling machines are much more efficient and accurate than point to point cnc machines, unless you have a really level machine that has good vacuum. We used to use a multi-spindle boring machine, but now we use a horizontal drill and dowel inserter. It is cnc controlled through an interface similar to p2p programming that anyone can do. It drills, injects glue, then inserts the dowel. We bought it at the 2010 IWF show and have been very happy. I recommend checking them out if you are going next month.
I agree, keep it and get a nesting machine. You made a good decision upgrading the bander first, I think. 3 options, at your volume for nesting. One is blind dados for cabinet construction, you might be surprised at how efficient a method this can be and is at least worth a good look. No horizontal boring required and thus no borer. Another is confirmat. Horizontal boring is required, but no case clamp, no square footage for a case clamp and no carrying the parts to and from the clamp. (That's a logistical issue that needs thinking through) Confirmat is what I do at considerably higher volume, but also with higher space constraints than many other shops. We also do only about 30 percent box work.
There are also connectors that do no require any horizontal drilling.
I have a much smaller shop, but I vote for blind dados on a nested machine, instead of dowels. Seems like the dowels add a couple of extra steps (and logistics as Mark said) after the parts come off the CNC. My blind dado parts come off the table ready to edgeband and assemble.
We have a slightly larger shop. A Komo nesting router that has been great. We also have a P2P and a Schelling beam saw. There are some things the P2P will do that the nesting machine can't or at least not easily. That said, I greatly favor the Komo nesting. I might think differently if we were doing very repetitive work where we could stack cut most of the parts on the saw.
All parts are moved on roller conveyors & transfer cars set @ 30" above the floor to keep from too much bending over. The conveyors have turned out to be even a better solution than I had hoped for.
We have a bore & insert machine with an 8' bed. Our machine is auto programmed from our software and we use bar code labels put on @ the saw or routers for the bore & insert. We have a pressure pot/glue injector at the assembly station right in front of the case clamp. Doweling is very fast. The bore & insert machine takes about 1.5 seconds per dowel. Most parts can be pendulum processed there. Assembly amounts to installing hardware, injecting glue, knocking the case loosely together sliding it into the clamp, push button, lock back in place, repeat. Cases are square! Next case can go in just as fast as you can get it ready, no waiting for glue to dry.
Most case are clamped on their sides, they go out the back side onto the table where they have any last parts installed. The clamp has a roller bed. The table top over hangs one end so when it is actuated the case comes to upright at floor level and is moved to the shipping area via hand truck. Not an ideal solution but the building has some limitations. The tilting table top was decided on when we got a contract to build a lot of tall, deep & heavy medical cabinets. We changed to a laminar type of case clamp that is also 900mm deep to accommodate the medical cases.
Not ideal, no robots (yet.)
I tend to agree that a nested based machine is the way to go. I would hang on to the P2P if you can, they can be useful for machining operations on the back side of parts. They're also useful for those odd pieces that really hold down better with pods. Not to mention when you have the occasional piece that is damaged or missing you can run it on the P2P without interfering with you nested production. Another handy feature is pendulum processing for parts that are repetitive. Final advantage is it gives you some kind of back up plan if your nested based router goes down!
I have used P2P machines for horizontal boring. I have used a Biesse Rover 13 (1995) and Rover 20 (2000). All my vertical boring was done on the nested machine then parts that needed it would come to the P2P and get the horizontal holes bored. I maintained pretty good accuracy so long as the seal on the pods was in good shape. Also found that board quality effected the accuracy. Board that is more porous ( lower quality MDF) or warped can be an issue. Obviously a dowel boring inserting machine is quicker and more accurate. But requires more expense.
I have also used a blind dado system. I think it makes a good strong joint and it's nice that everything is usually finished ready for banding when it comes off the machine. It does require a little more attention to slight variance in board thickness. It also requires all parts to be cut on the CNC (at least if you wish to keep it efficient) which can be a pain if one stretcher moves. If it was dowel construction you can simply recut the damaged part on the saw. I think each sheet takes slightly longer to
All the best.
Not to hijack this, but is any one using blind dadoes and a case clamp with some kind of fast setting adhesive? We currently use blind dadoes and screws, and then clamp up finish ends for commercial and applied ends for residential, but I do not like the look of the screws or the time it takes to put them in.
We are a commercial only shop, much of our work done to AWI standard specifications. I don't think blind dado meets those. Problems with dowels not holding can usually be traced to failure to inject glue @ the insert machine (usually poor maintenance!) OR using pre-glue dowels that have been exposed to too much dust & high humidity. We tested pre-glued dowels when we were first setting up our system. They work, didn't seem to hold as well and the assembler tended to put too much water in the holes and caused some undesirable swelling. Curable with training, maybe. The glue for the injectors is made for the purpose.
At the assembly bench the correct amount of glue needs to be uniformly applied. Could do it manually but an injector that controls quantity and distribution seems like a better idea, also faster. Speed is important once you start the glue.
The advantage of dowels in the case clamp is time. They grab really quickly. I don't know what the shortest time would need to be but I've watched videos of European factories where the automated clamp holds them for less than 15 seconds.
Much of the advantage to doweling can be lost if the entire system isn't optimized for it. Design, accuracy, training, maintenance, material handling.
Thanks Larry, my eyes will be wide open at IWF this year.Contemplating many things as we are constantly trying to improve quality and speed up production.We are and have been turning away work for the last 18 months.I am sure I will wish for another chance at some of that at some point in time.