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On another section, I had a question regarding the CNC laser machine I use to make gaskets and all sorts of other things. Happy to share what I know.

The machine is commonly referred to as a 3018. It has become so universally famous if you type 3018 into Google you'll see all sorts of these for sale. In the number 3018, 30 means it has a 300mm X axis and 18 means it has a 180mm Y axis. Hence the reason you can't make valve cover gaskets. 300mm is a bit shorter than 12 inches but you can't cut all the way to 300mm...more like 250mm. It is made in China and there are many versions of it all differentiated by size of work area. Such as 3040, etc. You can use it as an X-Y-Z axis machine (using a router-type motor and cutting bit) or you can use it as an X-Y only machine (with a laser head which you will have to purchase separately---the machine is designed to control either type of head). The router motor and bits won't cut gasket material at all. They tend to grab the material and tear it to shreds even if you secure it to the table. The most common laser head is a lower power diode type and it can be bought in a number of wattage outputs. The one I have is a 3.5 watt version. They do wear out if you use them a lot. You can figure the 3.5 watt model to cost between $60 and $90 or so. I have had to replace mine three times. If you are planning to use it as a CNC router (to shape plastic, wood, masonite, etc), I would definitely get the more expensive models with at least the 500 watt motor. You will need as much stability as possible. Down below you can see a piece of fiberglass I've machined to accept a radio inset piece. If you just want to set up a laser machine, you probably can do that for between $200 and $300 if you shop around carefully. If you just want a laser machine, you can get some that are not 3018 machines with a larger work area like this one: https://tinyurl.com/3cyv5fpw (I don't have one of these and have not used one but it looks interesting and it is controlled by some of the same software I use.

The movement of the laser is controlled by GRBL...at least that's what I learned to use. There are other programs like lightburn, however they are not free. GRBL is an open-source (meaning freely provided without cost) software program written to control lots of machines that make things. Basically you can use a JPG image file as input and with some manipulation convert it to instructions that tell the machine to reproduce that JPG image pretty exactly. Warning: it isn't always as easy as I may be making it sound. Some images require a lot of manipulation and time. The Carter YF gaskets took me something like 23 tries before I got what I wanted. Fortunately once you have the file set, you own it and you can repeat it rather easily. Outside temperature and humidity will have an effect on things and you must do this work outside as it will make your house smell like a bonfire if you do it indoors. The instruction file (an .nc file) is rather complex, however if you are curious and want to learn about the commands you can understand it. Image manipulation is the part that takes time and work and experience but you will get better at it. The movement of the router (since it uses the Z axis also) requires you to know something about engineering (CAD/CAM) and more complex programs. This water can get pretty deep on you, honestly speaking.

But let's just focus on the laser part for now since that's what the question was. With it, you can refine the image you want to "print" (laser print) and adjust the speed and strength so that you don't burn things up or fail to cut them. The laser beam starts when you tell the machine to print the image. Once you have worked and refined the JPG image enough and decided on the best strength and speed of travel, you can make gaskets like the ones you see below in the images. You'll need gasket material and you will learn not all gasket material is capable of being cut using a laser beam. Some of it melts, some of it catches fire, some of it simply will not work with the beam.

I hope this helps explain things. When I started this I had to learn from scratch. It isn't too difficult but it does require some practice and all.

Interesting info. Reminds me of when my youngest son talked me into setting up a 3D printer in our basement a few years ago. That was short lived, but it broadened my horizon.

Amazing how technology is evolving. I’m going to do a little reading on the subject.

Thanks for sharing.

John

John if you have any questions please let me know. I have rebuilt mine with new bearings and am considering expanding the Y axis to give me the ability to work on larger items. It came to me used. I mentioned I've made all sorts of things. I made some cork coasters for a county judge I know...Christmas presents for staff. You can see what they look like below. I also made a couple of hundred for our church with different scripture verses on them. Your imagination is a good source of ideas.

Jon, would the laser be able to cut thin copper sheet metal, like .040"-.060" thick or so? I've been considering commissioning someone to make copper shim head gaskets for 216 and 235/261 engines. Yes, I'm aware that the X/Y axis would need to have about a 30"+ X 8"+ travel capability, but it might be worth the investment over a long term situation to set up my own laser CNC system.
Jerry

Jerry as I understand the diode type laser will not cut copper sheet. I believe you'll need a fiber laser (different and much more $). However, the good news is if you had the more robust router type machine I believe you could cut .040 to .060" copper sheet using a small carbide tipped bit. The key (as I'm sure I don't need to tell you but will post for the benefit of others) is to lower the Z axis very little with each pass...maybe less than .1mm and possibly only around .01mm if you can manage it and to secure the copper to the worktable or spoilboard very well. Because of backlash in the lead screw and brass nut, most of these will not predictably handle .01mm but .1 to something like .05mm is usually okay. I believe I would use a 1/16" bit (two cutting flutes) and I'd limit the motor speed to 10,000 rpm or maybe less. I don't own one...I rely on a friend to help...but there are programs which will let you set up the shape, depth, etc you need and just walk away and do something else. You can see the image below. That is a fiberglass mold I made and then routed out the radio piece cutout. Using the program it takes about 20~25 minutes to make that cutout, and that's okay. You don't want to take bites that are too large. Once I was happy with the cutout, I made a silicone mold and from that I can make duplicates.

Back in the dark ages, a Bridgeport with a Tru-Trace system would be used for something like that, with about 5 layers of material stacked up. Later on, EDM machines would do the same job, faster and probably more accurately.
Jerry

Frequently I wish we could return to those dark ages, Jerry.

We had a Gorton Tracer mill back in the 70's and 80's. Very good rigid machine. It was made obsolete when we started investing in CNC machining centers.

John