Hey guys,
We are in a situation where we have been completely swamped beginning at the end of last year and continuing into this year as well. We are trying to get jobs out on schedule as best as possible but it is proving to be a little difficult as of late. We have determined our bottle neck is the cnc. It cannot keep up with the amount of parts that we need cutout daily. We also have two shifts running the cnc trying to keep up. My question is how many of you, when you are experiencing a busy stretch, cut your ¼’’ backs out on the cnc? We have thought about cutting all ¼’’ backs on the table saw to free up time to cut ¾’’ material on the cnc. This could be anywhere from 10-20 sheets a day. Have any of your shops cut ¼’’ backs on the table saw and let the cnc stick to the ¾’’ material? Thanks

Yes, that is a great idea. Removing some of the load from the bottleneck will result in a quicker turnaround. I have done this in my shop of removing some of the load from the CNC by using other resources to get the work accomplished.

After doing it on a temporary basis, we now do this year round as it made sense to continue doing that way. Freed up employee time to put toward other tasks that make more money than what they were doing before.

We are a small shop and we will even cut ANY backs or square parts on the saw while the CNC is plowing out dado's, rabbets, shelf pins, and non-square parts. If we are busy or there isnt other pressing things to do we will just pull at the backs from the nest and output them as a cutlist. Cutting rectangular parts with lighter material is one place that I think I can actual keep up or even beat the CNC with regards to time. No loading the program, no blowing down the table, no dealing with off falls, and so on.

We cut all 1/4" backs and drawer bottoms on the saw.

There isn't any time savings after you figure in sheet load/unload and cleaning the spoilboard.

Do you have or have room for an auto unload table?

Can you fit a second machine with offload?
Sounds like you have the business to justify it and the profit to pay for it with cash flow.

Not knowing what you existing Cnc is perhaps an upgraded machine might get you there.

I appreciate the responses everyone. We do have an auto unload table on our newer Weeke cnc. One thing I did not mention, because I wanted your feedback first, is we do have an older secondary cnc that we outgrew. It sits next to our newer cnc but it does not have an auto unload table. It seems like we are always having repairs made to this older cnc as well which can get costly. We've tossed around the idea to sell this older cnc and buy a $3500 table saw for cutting backs,etc.?

Yes you should definitely cut repetitive square cuts on the table saw. Or if you have the space you could buy an older beam saw for next to nothing.

You have to give it to the big CNC manufacturers, they did a wonderful job at marketing to convince people that they just have to have a $200k machine to cut squares from a sheet of plywood.

I don't think you need a $200,000 machine to do that. Let's say it is $100,000, Still not cheap!

What are the benefits of owning a CNC.
1.) Yield will be better in most cases.
2.) Tool cost will be less. I was shocked when we got a CNC that a router bit would cut longer than a saw blade by a lot.
3.) Speed, by a large amount.
4.) Versatility, it can do more than cut squares.
5.) Ease of use. The operator needs very little training to get an excellent results.
6.) The operator can be doing something else when the machine is running
7.) The machine does not get sick, come in hangover or get in a fight with its wife.
8.) Its more accurate.
9.) It does not make mistakes.
10.) It is hard to hurt yourself with a CNC machine.

What are you paying a person capable of running a saw all in?
I can't speak for everyone but if you offer benefits, paid vacation,worker comp and the administration of an employee it has to cost $30 an hour minimum. Thats $30 x 8 x 252 (labor x hours x days) or $60K a year.

Once you reach critical mass a CNC is a no brainer. If you need person dedicated to cutting parts boring, grooving, pocket holes..... a CNC is a good investment. That person is usually one of the more talented people.

If you had a CNC you would need to seriously consider how you assembled things. There is efficiency to be had by leveraging what a CNC can do.

So if you have the work and you drop 100K you can expect a $30-60K a year benefit for 8 years, Where can you get a return on your investment like that? I am not talking firing people I am talking deploying them to increase production.

Have you ever heard someone say I bought a CNC router and it was the worst investment I ever made? I have not.

Have you ever heard someone say I got a router and I can't believe I waited so long to get it? I have lots of times, it sure came out of my mouth.

Just trying to add to the dialog, at a certain point a Beam saw or slider or vertical make sense, I would not add a 10" table saw to cut plywood. It was not made for that.

Good luck

Have you thought about/do you use 3 flute outline/dado tooling? Your feed speeds can increase a ton from 1 flute or even 2. We went from a single flute diamond running around 175ipm to a 2 flute comp running 500ipm. The time difference per sheet is huge.

Tom, I'll check into this. Right now I know we're using 2 flute bits. Thanks

I use onsrud 60-126mw. I run 1000-1300ipm all day in 18mm Russian birch.

Make sure you call the tool maker. You have to include horsepower in the flutes,RPM, feed speed equation.

Travis,
Like it was mentioned earlier you need a beam saw, You can cut multiple sheets at the same time , then you can machine your gables for hardware on your cnc. This is way faster and more efficient than cutting individual sheets on your cnc.

If you want to crank out boxes, you need a Beam saw, Cnc, dowel machine and a case clamp. You need an edgebander regardless of how you assemble of course.

Our system separates the rectangular non-face machined parts and sends them through the panel saw optimizer, down load to beam saw. Even though single sheet cutting on the beam saw isn't very efficient it saves router time. I wouldn't cut parts that need to be rectangular on a table saw.

I 2nd Scott and Larry's comments. Keep the router machining the complex parts and everything else can be done on the beam saw..

The beam saws with multiple pushers and grippers that can cut different size parts at the same time are much more efficient for single sheet, small batch, lots of unique programs solutions than a traditional beam saw that is rip / rotate /crosscut a strip at a time.

I would estimate at least 35% faster and it would be higher with a turn table.

Check your feed rates and what is your nesting strategy in relation to the batch size ? Also, how many days are you nesting ahead of assembly ?