Hi All,

Over the past few years we have received tech support questions from some customers describing an infrequent pilot arc misfire on their Razorweld RAZORCUT 45 machines purchased from us. This misfire condition is characterized by the torch being commanded to fire in software but the pilot arc does not flash on and the plasma cutter blows air only. This misfire condition appears to be random and seems to be more frequent when cutting with a new set of consumables until they are properly ‘seasoned’. It does not affect all plasma cutters only some at random as far as we can tell.

This misfiring condition can be tested by removing the torch from the CrossFire torch mount and dry firing the plasma cutter in the air by hand in rapid succession. If your plasma cutter is experiencing this issue, you will notice that every so often the pilot arc will not come on and only air will blow out of the plasma cutter.

Customer satisfaction is always our number one priority and we have worked with Razorweld to determine the root cause of this issue as we understand that misfiring can be very frustrating when cutting on a CNC plasma machine. During investigation, it has been determined that this issue is
caused by improper timing delay between the electrode start current and the air solenoid valve.
Fortunately, a field repair using off-the-shelf supplies can be easily performed to fix the issue. Razorweld has issued the attached TECHNICAL BULLETIN that describes how to repair your plasma cutter at home if you are experiencing this issue and want to fix it yourself. RW45 MISFIRE TECH BULLETIN.pdf (994.5 KB)

If after reviewing the TECHNICAL BULLETIN you are confident that you are experiencing this issue on your RAZORCUT45 machine but do not feel comfortable performing the repair yourself, you can contact sales@razorweld.com to facilitate a repair at their warehouse. We ask that you please ensure that your misfire is not caused by incorrect operating procedures such as dirty air, irregular Air pressure or worn out consumables and that your machine is not in Air check mode or inconsistent input power commonly caused by running your Plasma cutter on an extension lead.

Thanks again and happy cutting,
The Langmuir Team


So I have to modify a machine I bought from you to work, mine FREQUENTLY MISFIRES and has cost me a ton in ruined parts, when the problem is yours all along. Please send me a machine that works, I didn’t pay to have to modify a machine. This should have been known long ago!!!

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@slimbourne we understand your frustration but want to remind you that we are simply a reseller for these plasma cutters. We have listened to our customers and that is why we have worked with Razorweld to get this issued fixed for good because we are committed to customer service. In addition, this issue does not affect all plasma cutters and appears to be random. We invite you to contact Razorweld, we promise you are in good hands with them and they will work with you to get your Machine in good working order.

The reason they published the bulletin is because the fix is fairly easy for someone that has the tools and doesn’t want to risk down time with their machine waiting to ship it to Razorweld and have it repaired. It is just another option for certain folks that feel comfortable with the repair. Thanks again for understanding we really appreciate your business!

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“If after reviewing the TECHNICAL BULLETIN you are confident that you are experiencing this issue on your RAZORCUT45 machine but do not feel comfortable performing the repair yourself, you can contact sales@razorweld.com to facilitate a repair at their warehouse.”

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Stupid question, will this repair void any warranty from razorweld? I don’t mind doing it however I’d hate for razorweld to not back their machine as it has been modified.

You are free to perform the repair as described in the tech bulletin without risk of voiding your warranty. Thanks!


Who is going to cover the shipping to and from Washington state to get your plasma cutter fixed?

Please reach out to sales@razorweld.com and they will facilitate the repair claim and logistics with you. Thanks again!

As soon as I got the email about this today I went and got a new resistor to do the mod. The C101 came off fine but the pad for R121 came up with the old resistor. I guess I’m looking at a new board. So from what I’ve read I can contact Razorweld and they’re going take care of it? Funny the guy I talked to Wednesday at Razorweld told me cranking the pressure to 75psi with the torch firing and no extension cords would solve the problem.

The customer will be responsible for the shipping back to Razorweld. Razorweld will cover the upgrade and shipping back as well as some product.

This is not a faulty product and is a modification to the main board which allows more power (firing rate) to run from the main board to the torch.

If anyone has any questions after reading the flyer and making sure that all procedures are followed please reach out to sales@razorweld.com.

Sounds like a defect to me especially if some units do it and others don’t. I ordered the crossfire xl combo with this cutter. My cutter shipped the day this bulletin was published. Did I get a good one or not? Seems since this has been a known issue it should be addressed especially on new units being shipped. I am thinking I may just send back unit for refund and get another compatible cutter if possible.

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Sounds like a faulty product. It worked great then stopped working as designed. Thats faulty. I’ve been dealing with this issue for over three months now. I added an air dryer, two more air filters, re-wired the plug in my shop, swapped out torches, countless consumables, down time and wasted material. Have the fortitude to stand behind your product and take care of your customers.


Upon further investigation I found that the pad that came loose is connected to the pad above it so I was able to do some creative tweaking to the new resistor’s wire to complete the circuit. I want to give a shout out to those who helped me with it. You know who you are…



Well on one hand shit happens. On the other this is disappointing. I got box 1 about a month ago (the razor 45 plasma cutter) and I am still waiting on the rest.

My question for Langmuir is, can I simulate the failure right now with just the plasma cutter? IE will it happen with the manual trigger? IF I have this problem with my new machine, I would like to do the fix before also trying to learn the rest.

Thanks for any info!


(I have not even unboxed the cutter and plugged it in)

Yes- Unbox it and air fire if 20-30 times. If it misfires during the course of that test I recommend performing the mod.

Thanks for the reply. What do you mean “air fire” it - you mean just pull the trigger with no metal destination for the plasma?

This is very disappointing response from Razorweld. It seems that all these machines are defective, but they don’t have the budget like a big manufacturer to make us whole. I’m even more dissapointed by Langmuir that they are not doing more. Many of us bought the ‘package’ because it was turnkey and would work the most often over other alternatives. Sigh… But maybe fixing could be be better than a big paper weight.

Yes that is correct, just hold the torch out in the air and fire it 20-30 times. You will know if it is misfiring.

There’s a much safer and easier way to remove a surface mount device than what the instructions show. Use two irons like chop sticks and heat both pads at the same time. The way they suggest usually damages the board.

Do they give a recommendation for wattage of the replacement resistor? Is there any reason a proper fitting SMT resistor can’t be installed? Tacking a through hole resistor on like they suggest will almost definitely give problems in the future.

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