Arc welding on an RV can be risky but necessary to repair your RV. Not to worry, this type of repair can be performed safely and effectively as long as you take proper precautions to protect yourself and your RV.
While this work is typically done in a shop, there are mobile welders that can perform the work at your campground, or even a boondocking spot.
I have witnessed a few RV welding repairs and spoken to the welder doing the work. Much of what I will share here is based on those conversations.
What are the risks?
Welding is dangerous and takes a lot of practice to master. So it is important to hire a certified welding professional who will accomplish this job safely and effectively. A good welder can provide proof of his certification and help assess the risks involved with your project.
Unrealistic Expectations. If hiring a welder, make sure that you and the welder have a clear understanding of the work or repair being performed and what the expected outcome is. Some repairs may be merely temporary to get you down the road before a permanent repair can be made. You should both be on the same page before starting.
Potential damage to electronics. Surges in electrical current flowing through the chassis could damage your electrical equipment. The electrical system in an RV uses the steel chassis as the electrical ground. The welding equipment is also grounded to the RV chassis. A qualified welder will take steps to contain the electrical current to the work area as much as possible. You should also take precautions outlined in this article to protect your equipment.
Risk of fire. As one welder put it “RVs are tinder boxes”. So extra precautions should be taken to avoid fires. Having a fire extinguisher within reach is a necessity. The welder may also want to spray water or flame retardant on surfaces nearby the work area. Its is also good practice to stop between welds to inspect the surrounding area.
How does the welding process work?
Here is a very basic explanation of how welding metal works. Metal is heated to its melting point while welding rod (of some form) is fused into the gap to bond the pieces together.
The most popular welding technique for this repair is Arc welding which uses electricity to heat the metal. A large amount of electrical current (created by the welding equipment) passes through the metal pieces while welding.
Does welding cause electrical current to flow throughout the RV?
Not necessarily. If done properly, the only the metal around the welding area will be affected.
A clean bare metal surface is necessary to create a good bond between grounding clamp, welding surface and welding electrode (a.k.a. welding rod). If a good bond is achieved, then the electrical current from the welding process will flow in a short loop through the welding area and welding equipment, not through the RV chassis.
Location of the Grounding Clamp is critical? The welder will choose a suitable location for the grounding clamp. This location will be as close as possible (within a few inches) to the work area. This creates a very short loop for electrical current to travel.
Prior to welding, the welder will clean and grind the affected areas (down to bare metal). This includes the area to be welded and grounding clamp location.
When welding starts, electrical current will flow from the welding electrode, through the grounding clamp and back to the welding equipment.
What to do before welding?
Take these precautions to protect yourself, your RV and electrical equipment.
- Disconnect from house and chassis batteries by removing the negative battery terminal
- Disconnect from Power Source (Shore power / Generator)
- Disconnect from Tow Car or other Grounded Equipment
- Turn off the valve on your propane tank
- Turn off propane appliances
- Turn off your power inverter and other sources of power like solar panels
- Unplug sensitive electronics inside your RV
- Have a fire extinguisher ready just in case
If you plan to be on-site while welding is being performed, remain outside your RV and follow all instructions and precautions the welder may give you.
Be prepared to sign a release of liability
RVs are highly flammable which makes welding on an RV very hazardous. A qualified welding professional will take all necessary precautions to avoid fires and damage to your RV. Regardless, there are still unexpected risks. To mitigate this, some small shops or independent contractors may ask you to sign a waiver of liability before doing the work. Keep in mind you always have the choice to decline.
What to do once welding starts
Stand clear and don’t look at the welding area without protective eyewear. Also, avoid interrupting the welder. Welding is a highly focused and dangerous task. So give the welder some space to work.
Conclusion
I hope this helps to alleviate any worry about welding repairs on your RV. There is no need to be afraid of getting welding work done when necessary. Everything should go smoothly if you communicate clearly and follow instructions from your welder.
Finally, don’t be afraid to ask the welder any questions about their process and recommended precautions beforehand. Surprises are not a good thing with this type of project. In my experience they will likely ask you first if you have any questions before they start.