Happy New Year!
I hope 2006 was a great year for you and 2007 will be even better.
The two Fein Turbo III vacuum system I wrote about in the last article got a good testing the week before Christmas. The largest job I have run to date was completed on time and brought forward several inefficiencies in my shop. In running this job I found that a lot of little things which had not been a source of irritation in the past became much more pronounced. I’ll go over them and how I solved – or attempted to solve – them.
First, my shop is too small. Since I will not be adding to it anytime soon, I have to find another way to overcome this. I have read posts in the past on various forums about workflow, the triangle and dedicated machines. How could I put all of this information to good use in my shop? As you can see from the pictures below, I moved the ShopBot just a little so there was no longer a 90 degree angle between my sheet goods storage rack and the machine.
 Before |
 After |
This helped me in pulling sheets from storage and loading them on the machine as well as taking parts off of the Shopbot. This 45-degree shift effectively gave me three times the floor space at the end of the machine.
Second, it takes too long to cut a sheet of parts. At first glance this might not seem like a problem if you are charging by the hour, but you only have so many hours in a day and deadlines have to be met. This job required me to use a .25” bit as I didn’t have enough room to nest all of the parts and use a .375” bit like I wanted to so I felt I needed to slow the feed rate down. This did not help the fact that I have a deadline to meet. From past experience, I felt that I didn’t have the quantity of .25” cutters that I would need for this job, either. Can you feel my stress building? OK, here is what happened – I happened to find out about a tool manufacturer just 15 miles from me. I thought that would solve the lack of cutters I had on hand. One quick call and I learned that they only had three .25” up spiral cutters on the shelf. They custom make cutters for shops, so they do not stock them. I got the three cutters, and when the owner learned I was still new to CNC he moved into tutor mode. I have to say, he didn’t tell me anything new from what I have been told at ShopBot, the Jamboree or any of the Camps. For some reason, I just felt that slowing down the router and speeding up the ips was not the thing to do. Do you see where this is going? Lesson learned here is pay attention to the built-in chip load calculator in your ShopBot software. It is there for a reason. Use it! I ran the router at 10K RPM and was cutting at 7 to 9 ips, and the machine, cutter and the wood loved it. No more 3 ips and 20k for me. The bit did not turn black, not even brown. I didn’t break a single bit and only used two, not the 10 I expected to use. Please use the chip load charts and experiment with feeds and speeds. There are a lot of folks on the ShopBot Forum with answers as well as the folks at ShopBot. Ask them where to start if you are having trouble.
Can I get better cut quality? I am using that .25” up spiral bit I got just down the road and the bottom side of the Maple Ply is fantastic… the top is chipping out a little. This is not the quality I want to send out. As simple as this is to fix, in my state of panic to run the job on time, I missed something simple. You have to remember, I do not have any special cutters on hand right now and the job has to be run. I have up spirals and down spirals as well as straight cutters only and no time to order more. I emailed Brady Watson and asked for his advice, smart move on my part here. Brady answered and I could have smacked myself after reading his response….. use a down spiral to cut into the material and then an up spiral to finish it. Let me tell you this, the cut quality on this Maple Ply is better than the factory edge. Again, listen to folks and experiment. I have to say that changing the bit for each sheet was not a problem and it went quickly.
I said that I would share how I solved or attempted to solve my problems above. So far every problem was solved. Here is the one I am still working on. Power or torque. My Porter Cable router 7518 is feeling the increased cut depth and speeds I am now cutting with. It is working just fine and I am satisfied with performance. I would like to not hear it bog down when I start a cut and wait for the electronic speed control to notice it is turning too slow and speed it up. The noise from the router running at 10K to 13K is not bad. Faster than that and it is quite loud. My next option is a spindle. Maybe I’ll be able to cut even faster with one.
The last bottleneck I encountered was trying to use the ShopBot control computer to do design work and run the machine. Doing both is possible, but not at the same time. Remember, I need to get this job run quickly. I loaded my software on a second computer and was able to draw a sheet while one was cutting. Easy to solve, if you have the second computer handy.
From all of this I have learned that not experimenting and finding the optimum feed, speed and cutter for a job before the job is due is not smart. Not having a selection of bits on hand is not bright either. Running the router too fast and the ips too slow burns up bits, breaks bits and doesn’t help anything. Asking the folks at ShopBot or posting a question on the ShopBot Forum will give you access to the vast experience of the many users that frequent the board. And best of all, I made the right choice in buying the machine that I did.
I have been experimenting with v-carving more than usual so next time I plan to share some of my blunders -er- learning experiences with you on why a 120-degree bit might be better than a 90-degree bit in some applications. Maybe even a comment or two on a spindle vs a router, but don’t hold your breath on that one just yet.
One of the highlights for me last year was going to John & Doug Roughton’s shop located in Kitty Hawk, NC for a wonderful Camp. Thank you guys for a wonderful fun and education-filled weekend. I look forward to this camp next year!!
Folks, if you have not been to a ShopBot Camp before, you are missing a big opportunity to learn from others and see how others are doing their work. There is always something to be gained from sharing your ideas and methods with others.
Now go and make big sheets or boards into smaller ones and gain the experience to cut faster and better with less stress!