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Laser Maintenance – What To Look For When Buying A Used Laser

Jan./Feb, 2011

When buying a used laser system, what should a company be looking for?

Before you consider a used laser, your first question and the most important one should be: Exactly how will I be using this laser?

Before you purchase a machine to solve a problem or improve a manufacturing process, you need to know exactly what it is you want to accomplish once you have the machine.

Do you need a laser that is versatile because you are a job shop or one dedicated to running a specific product? Lasers are capable of processing a large range of different materials such as ceramics, composites, plastics, wood, glass, mild steel, stainless steel, aluminum and many other materials.

Each material will have different laser requirements: For example, when processing aluminum, the more power you have the better off you’ll be. On the other hand, mild steel can really only absorb so much power before it becomes a melted mess.

When processing 10-gauge-thick mild steel with oxygen, it will process similarly on a 1.5kW laser as it does on a 6kW laser, but the cost difference to operate and purchase these machines is exponentially different. Not all lasers are created equal. Some machines will out perform others, or they won’t even be capable of accomplishing the tasks you need. It’s a good idea to take your material to the laser manufacturer from which you’re interested in buying, and having them process a few of your parts.

Budget

Once you know the requirements of the laser you need, set a realistic budget. The original cost of the machine is just the beginning. First you’ll need a technician to prepare the machine for delivery. Each manufacturer and their different models will require a different amount of labor to move the machine. Machines could be wired with numerous wire connections or they may have quick disconnect plugs that save time and eliminate reconnection errors.

Determine how the laser is anchored to the floor, because this can also affect the overall purchase price of the machine. Some manufactures design their machines for easy movement, while others are, shall we say, expensive to move. Check how the frames are built and the overall size of the laser, as all this will determine the cost to deliver the machine when you include road permits and rigging costs.

Once the machine arrives at your factory, the process is reversed, but this time you might have troubleshooting costs for the relocation to deal with. Again, labor is determined by the manufacturer’s design and the technician you chose to uninstall and reinstall.

An experienced technician with your particular model could save time and money, as they know exactly what to do to install and reinstall the equipment. You’ll need various regulators, gas bottles or bulk assist gas storage, too, so budget for gas line plumbing and an electrician to provide power to the machine. Don’t forget to budget for a way to load material onto the laser, either with a jib crane and vacuum lift, overhead crane or an automated system.

Furthermore, you might need to budget for any repairs required that were neglected or overlooked by the previous owner (this is always something you should check out before you purchase). You’ll want to buy the basic consumables, such as focusing lenses, cutting tips and cleaning supplies. Each manufacturer will have a list of recommended parts to stock. You’ll need to budget for software to convert drawing files to CNC ones that your machine is capable of using. Then you need to train the programmer on what codes are required to optimize your new purchase. Of course the operator will require training.

You don’t want a PHD degree (Push Here Dummy) for an operator. Lasers are not a push button machine to operate. The operator really needs to understand the machine and the process to make adjustments for variations in the cutting process. 

Examine the machine’s control for ease of use. If the control is difficult, training will be costly not only for the original operator, but also for any future operators you’ll need to train. In the purchase price, determine the cost to operate the machine for a year, including an hourly basis to have a technician service the machine for routine and unexpected breakdowns.

Consider a turn-key deal where you pay one price for the machine installed and properly working. You might also request to send an operator to the current owner to work with theirs as part of the training. Keep in mind you might pick up incomplete information or bad habits, though.

Previous Maintenance

Request the maintenance records during the laser’s inspection. You’re looking for several things. First, make sure they’re keeping good timely records according to the manufacturer’s recommendations. A lack of records is never a good sign. Second, look for patterns in any repairs – repeat problems will have a cost associated with them and a glimpse into your future costs. You definitely don’t want to see a stack of records indicating a constant repair burden.

Look at the hours spent repairing or maintaining the laser and the costs if they are available. Verify the total hours on the machine. Most manufacturers will have hour meters for key components such as the turbo, roots blowers and radio frequency tubes. These parts can be expensive, and you need to know when they were last replaced and how much life is left in them.

Obsolete Parts

Your budget will dictate how old of a laser you can afford, and as lasers age, parts get harder to come by. You might be naive to think that the machine is only 10 years old and parts are still available for it. But manufacturers purchase parts from other manufacturers as well, and their supplier might go out of business or discontinue manufacturing older product lines.

Normally, lead times for laser parts will stretch out from overnight delivery to six to eight weeks, and eventually they’ll become obsolete. At this point, you can either retrofit or upgrade if possible, provided the cost doesn’t exceed your original purchase price or budget. This is really a difficult subject to address without involving the manufacturer’s parts department or experience with the machine and manufacturer.

Tolerances

Your parts will require different tolerances and each laser manufacturers’ machines are built with different standards or capabilities. Their cutting tolerances can vary from 0.002 in. to 0.006 in. when new. If you’re purchasing a used machine, these tolerances will change with the machine’s age, how well it was maintained and the drive system used. Cut a few samples of your parts and check the results for yourself.

Machine modifications

Over the life of a machine, some owners will modify them in various ways. Some will be good and others less desirable. Previous owners may modify their machines for financial reasons. The machine broke down and the purchasing agent decided to shop around for a part that looked like it would work to save money. The key word here is that the part LOOKED like it was the same. Manufactures specify parts for their machines for several reasons: function, reliability, quality or possible space limitations.

Some similar parts might cause inconsistent results from a timing function in an electrical circuit or might not have the same strength in the material composition for a mechanical part. These could cause a safety issue for the machine or your personnel if or when they fail. Obviously there might be ones that will meet or exceed the manufacturers’ parts, but you need to know when and where they can be used.

Perhaps the previous maintenance personnel has over-road safety interlocks or removed safety guards to make it convenient for them to use the machine in a way that it was not designed for. Again, the safety concerns for new personnel working on the used machine might allow them into a high voltage or a mechanical pinching area that could cause serious injury without their knowledge.

Used machine dealer

If you’re buying from a used machine dealer, is the company capable of supporting the machine? Do they have service personnel? Are they factory trained and are they aware of the proper procedures to maintain your machine? How many years have they been selling and supporting machines? Do they have references you can check? If there is a machine issue during the transfer, who is responsible for the damage or repair?

Look, watch and learn

You don’t have to be technically minded to gather information about the laser’s current condition. Make sure when you inspect it that you spend a little time with the operator and maintenance personnel. Ask for a copy of their records, and what they like and dislike about it. You will be amazed at the things some people will tell you. Remember they probably won’t gain a anything by being honest or dishonest with you, so they normally give you information without even realizing it. Just have a causal conversation with them, because if you start drilling them for information, they might feel the pressure.

Watch the operator work as they process steel. Does it look like the laser is easy to operate or is the operator tweaking the machine to keep it cutting properly? Ask what type of machine will replace the laser they’re selling. If they are switching brands, why? Look at the edge quality of the parts after cutting. Do they have dross, burned holes or corners?

Look at the cutting feed rates. Ask if they’re cutting to the manufacturer’s recommended speeds. Look at the CNC control on the machine. Does it look like a logical layout for someone to use? Look at the overall appearance of the machine. They knew you were coming. Did they clean the machine to present it well, or does it look used and abused?

Warranty

When you purchase a used machine, they’re normally sold “as is, where is” without any explicit warranty implied. However, some used dealers will offer a 30-day warranty typically on some of the more expense items that could fail. Others might offer a 30-day return policy with only one catch – costs associated with shipping, rigging, installation etc. will not be refunded. Remember. if they tell you it’s a great machine. ask them to back it up. It never hurts to ask.

Summary

If you’ve been following along, you should be armed with enough information to help you sort out a good machine from a bad one. Purchasing a used laser is similar to buying a used car, just more expensive. Everyone likes to get a bargain or a great deal, and occasionally you may find a one. However, too often a good deal ends up in favor of the seller. They have the upper hand, they know the complete history of the laser. They might even know which parts are about to fail and that might be why they’re selling.

Of course, there are good used machines on the market. Do your homework and purchase the machine that fits your needs, not just the budget. You can also search the internet for current prices for similar machines.

Since there is no Carfax-style documentation for lasers, rely on the expertise of a laser technician that is familiar with the manufacturer and model that you have an interest in. It will be money WELL spent.