Copper Nickel Brake Line – Dave’s Garage

Progress is great. When a product appears on the market that increases the safety, service life, ease of maintenance, and the performance of our cars, it is a good thing. Perhaps you may have noticed there is a new type of brake line on the market.

A little history- Before WWII, many manufacturers used copper brake lines. Copper is both easy to form, and resists corrosion well. Unfortunately, copper is also prone to cracking. Shortly before the war, there was a transition to steel tubing for brake lines. Steel did not have the cracking problem of copper, but it did corrode. Steel brake lines would often fail after only a few years of use. The options to prolong the life of steel brake lines included many types of coatings to protect against corrosion.

Steel brake lines failing due to corrosion was not acceptable to safety obsessed Sweden. Both Saab and Volvo experimented with epoxy coatings, anodized steel and various other coatings to protect the brake lines. Volvo introduced a new type of brake line in 1976. This new brake line consisted of 89% Copper, 1% Iron, and 10% Nickel. This alloy proved to be durable with the corrosion resistance of copper and the crack resistance of steel.

Years ago when doing repair work I found steel brake lines would only last a few years before they would fail due to corrosion. I used anodized brake line exclusively for the last ten years or so. This anodized line lasts much longer than bare steel line.

Copper-Nickel tubing is much easier to form than steel, resists kinking and virtually will not corrode. I have found that a tubing bender is useful, but not necessary to bend Copper-Nickel tubing.

Cutting and bubble flaring Copper-Nickel tubing is actually quite easy. As with steel tubing, it is imperative to start with a nice, clean square cut. Nothing but a sharp tubing cutter will do.

Make sure there are no burrs on the end of the tube, and that you have a nice clean cut. Like steel, it may be necessary to dress the cut tube with a fine file before flaring. Unlike steel, I have found it is NOT necessary to chamfer the fresh cut end of the tube before using the flaring tool.

copper-nickel brake line
Because the Copper-Nickel is softer than steel, I found I have to be more gentle with a bubble flare tool. It takes far less effort to drive the mandrel in to the tube, and to pinch the final flare. I also found that it works better to use a tad more material for the flare than with steel. When installing and tightening the flare nuts, I found it takes less effort to tighten the fittings with no leaks. The Copper-Nickel tubing has more “squish” than steel.

I recently replaced all of the brake lines on my Chrysler minivan. With the ABS pump, proportioning valve, duel circuits and the many transitions to rubber hose and back to metal, there were many individual lines to form and many fittings to flare. The Copper-Nickel was far easier to work with than steel would have been. When I finished the job, there were no leaks.

Copper-Nickel brake line is stocked at most auto parts stores, and the price is comparable to anodized steel tubing. Do yourself a favor and try some the next time you have to replace a brake line. You won’t be disappointed!


Please email all inquiries to: Dave
or snail mail
32 Turkey Hill Road
Richmond VT 05477

Trailer Tires – Dave’s Garage

Trailer tires have a tough life. Drivers are unlikely to feel any notable differences in road noise or road feel with trailer tires. Trailer tires are often subjected to harsh curb hits and road bumps. Tandem axle tires also experience harsh scrubbing due to making tight turns in parking lots and on corners.

trailer tiresTrailer tires are quite different from traditional passenger car and truck tires. Trailer tires are not designed for either tractive effort or steering adhesion. The tread design is not optimized for ride comfort or noise reduction. Most importantly, the side walls are designed to reduce trailer sway and provide optimum control.

The two biggest enemies to trailer tires are abrasion and heat. As trailer tires heat up, their structure begins to disintegrate and weaken. The load capacity gradually decreases as the heat and stress caused by higher speed increases.

As with any tire, trailer tires have a “shelf life.” Time weakens a trailer tire too. Three to five years is the projected life of a trailer tire. Obviously, the type of use and number of duty cycles influences the service life of the tire. Weight carried and speeds driven are the biggest factors influencing tire life. In approximately three years, roughly one-third of the tire’s strength is gone.

The mileage life of a trailer tire is generally 5,000 to 12,000 miles. Which tires should you use? Trailer tires should match each other, and the load rating should ex-ceed the combined weight of the trailer and load by about 20 percent.

What is a tire with a rating of “ST”?
“ST” tires feature materials and construction to meet the higher load requirements and demands of trailering. The polyester cords are bigger than they would be for a comparable “P” or “LT” tire.

The steel cords have a larger diameter and greater tensile strength to meet the additional load requirements. “ST” tire rubber compounds contain more chemicals to resist weather and ozone cracking.
Always inflate trailer tires to the maximum inflation indicated on the sidewall. Check inflation when the tires are cool.

If the tires are hot to the touch from operation, add three psi to the max inflation.

Under inflation is the number one cause of trailer tire failure. An under inflated tire will flex needlessly, and run much hotter than a fully inflated tire.

Keys to Avoiding Trouble from Carlisle tire

  • The ideal storage for trailer tires is in a cool, dark garage at maximum inflation.
  • Use tire covers to protect the tires from direct sunlight.
  • Place thin boards or plywood sections between the tire and the
    pavement.
  • Clean the tires using mild soap and water ONLY.
  • Do not use tire-care products containing alcohol or petroleum distillates.
  • Inspect the tires for any cuts, snags, bulges or punctures.
  • Check the inflation before towing and again before the return trip.
  • Replace trailer tires every three to five years, whether they look like they’re worn out or not.

Trailer Tire Warranty

  • The Carlisle trailer tire warranty applies to the original purchaser for three years from the date of purchase or until the tread depth reaches 3/32″.
  • The OE (original equipment) warranty goes into effect at the time of the trailer purchase

Please email all inquiries to: Dave
or snail mail
32 Turkey Hill Road
Richmond VT 05477

 

Brake Down – Dave’s Garage

Five or six years ago the Jaguar XKE started to run rough, cough, belch black smoke, and backfire. This problem got worse quickly and the car ran so poorly it could barely move. Life got in the way, and the Jag was parked.

jaguar xke brake cylinderThis summer I decided it was time to figure out what was wrong with the car and fix it. I found a sunken carburetor float in the rear carburetor, a torn diaphragm in the front carburetor, a bad fuel pump and a dead battery. Once I got these issues sorted out, I began to tune the car and get it running again. It soon became apparent that there was an issue with the brakes. Both front and rear brakes were dragging, and the pedal did not feel right. I know that the brake fluid has not been changed in at least 15 years. When I removed the caps to inspect the brake fluid, I found a nasty surprise. We all know that brake fluid absorbs moisture. Due to some spring flooding this year, the building the car was stored in, had several inches of standing water on the floor of the garage.

The brake fluid actually had standing water pooled on top, and the fluid was starting to congeal. The aluminum caps for the fluid also have low level switches in them. The aluminum had rotted away, and the caps fell apart in my hands. I used a turkey baster to remove the fluid, then flushed fresh new fluid through the system and out the bleeder screws. It is amazing how corrosive contaminated brake fluid is. Look at these pictures. This damage could have been avoided if the fluid had been changed every two or three years.

An extra Tip……… I was recently shopping at Tractor Supply, and I bought a new battery cable for my tractor. When I installed the new cable, I noticed the diameter of the cable was much thicker than the one it was replacing. I realized that the cable I bought was suitable for a six volt battery. A six volt battery cable needs to be thicker, because it carries more amperage at a lower voltage. Six volt battery cables are hard to find at an auto parts store, but Tractor Supply has a large selection in stock.

Please email all inquiries to: Dave
or snail mail
32 Turkey Hill Road
Richmond VT 05477

Water Pump Grease – Dave’s Garage

A lot of our antique cars have, or had a grease fitting or a grease cup on the water pump. Without the proper grease, the water pump bearings will quickly fail. In some cars, particularly Model A Fords, the grease may pass through the water pump in to the cooling system. Ford specified a special water soluble grease. Using a conventional grease can cause a blockage in the radiator. Chrysler specified a special grease for use on their water pumps too.

water pumpSo, what makes water pump grease different than conventional chassis grease? Depending on the grease, it is either a grease that won’t be washed away by water, or a water soluble grease that will wash away and dissolve in water preventing a blockage in the cooling system.

Many replacement or rebuilt water pumps have modern, sealed bearings. Most of these pumps use the original casting and either have a grease fitting, or grease cup, or a spot for the grease fitting to be fitted. Many concourse restoration pumps actually have dummy grease fittings or grease cups to “look the part” of the factory pump.

The question is, what grease to use? If you need a water soluble grease, such as for a Model A, most Model A parts- houses stock the water soluble water pump grease.

There are several options for non water soluble grease. Most auto parts stores stopped stocking water pump grease decades ago. The most popular modern replacement is marine grease, or the wheel bearing grease for boat trailers. Many people use Lubriplate 115 for water pump grease. Marine shops carry outboard motor grease. Another option is your local fire department. The pumps in fire trucks requires a special, water pump grease. This grease is sitting right on the shelf at the fire house. If you are lucky, they may give you a few pumps from their grease gun, or several ounces from the tub they are using.


Please email all inquiries to: Dave
or snail mail
32 Turkey Hill Road
Richmond VT 05477

Polyurethane Bushings – Dave’s Garage

I am a believer in keeping things original, to a point. Sometimes I have an opportunity to take advantage of an improved technology, and I use it. One such example is the substitution of polyurethane bushings in place of rubber bushings in suspension systems.

I replaced the sway bar bushings several times in my Chrysler minivan. Sway bar bushing failure was a known problem. I was reading about this problem on line, and I read a suggestion of replacing the bushings with urethane bushings in place of the OEM rubber bushings. I reluctantly did the substitution, and was very surprised to see that not only did the urethane perform much better, but they also held up better. I have not had to replace them since. By the way, even Chrysler acknowledged this problem, and have since substituted urethane bushings as replacement parts in this application.

I am not talking about the cobalt blue or bright orange bushings people use to dress up a chassis, I am talking about black urethane bushings, that look just like OEM rubber bushings.

I have recently replaced all the suspension bushings in three English cars. Two of these cars are cars that I rebuilt the suspension on years ago. In all three cases, the rubber had deteriorated and failed. I ended up replacing the bushings in the lower A arms of the front suspension, sway bar and the bushings on all the leaf springs and spring shackles with the new, and much improved urethane bushings.

After dis-assembly and cleaning, I put a thin film of grease on the new bushings before I assembled them, to prevent squeaks. In all three cases, the cars drove better, the suspension was tighter, quieter, and suspension travel was smoother. I was astonished at the improvement in performance over the rubber bushings.

These bushings not only perform better, they will also look “new” indefinitely. Check your favorite parts supplier or look on line.


Please email all inquiries to: Dave
or snail mail
32 Turkey Hill Road
Richmond VT 05477

Brake Fluid – Dave’s Garage

This month we have a question about  brake fluid from Ed Hilbert.

Hello David,

I am redoing all of my Mercedes brake components except for the steel brake lines which appear to be in good shape. What are the different types of brake fluid and when to use each type? Would I do well to change over to the newer silicone brake fluid or stick with the standard DOT type 3?

What are the advantages of the silicone over DOT 3 – perhaps silicone won’t absorb moisture and thus lessens the chance of rust? If I do change over, must I completely flush out the old fluid and if so with what – alcohol? How incompatible are the two types of brake fluid?

What is brake fluid made of? Why is it used instead of standard motor oil?

Can it be used as a paint stripper? If so, how would one clean it off the surface so paint would stick again?

Anything else we should know about brake fluid?

Thanks for your expertise!
Ed

Dear Ed,

The types of brake fluid are DOT 3, DOT 4, DOT 5 and DOT 5.1. DOT 5.1, like DOT 3 and DOT 4, is a polyethylene glycol-based fluid (contrasted with DOT 5 which is silicone-based). Polyethylene glycol fluids are hygroscopic and will absorb water from the atmosphere, necessitating a flush/replace every couple of years. Polyethylene glycol fluid WILL absorb moisture. Failure to replace contaminated brake fluid will lower the boiling point of the brake fluid, and the moisture will cause rust and corrosion of the brake system. Silicone, DOT 5 fluid will absorb just a minuscule amount of water.
Brake fluid is classified by its boiling point. The “dry” boiling point is with no moisture in the fluid. The “wet” boiling point is brake fluid with moisture in it. “Wet” brake fluid is defined as having 3.7% water by volume.

Dry boiling point Wet boiling point

  • DOT 3 205 °C (401 °F) 140 °C (284 °F)
  • DOT 4 230 °C (446 °F) 155 °C (311 °F)
  • DOT 5 260 °C (500 °F) 180 °C (356 °F)
  • DOT 5.1 260 °C (500 °F) 180 °C (356 °F)

I would highly recommend changing over to the DOT 5 Silicone fluid. Cars that I switched over to Silicone in the early 1980s have no issues, and the fluid continues to function well.

DOT 4 brake fluid has a higher boiling point than DOT 3, and is specified by many manufacturers for better braking performance.DOT 3, 4 and 5.1 brake fluid will remove paint, but there are much better paint removers. DOT 5 fluid, Silicone, will not harm paint. If it is accidentally spilled on the paintwork, it will not damage the paint, and can easily be wiped off.

I would imagine surfaces contaminated with brake fluid could be cleaned up successfully before painting.

DOT 5 Silicone brake fluid does have some drawbacks. It is very expensive, much more expensive than DOT 3 and 4. DOT 5 fluid can absorb air bubbles, and these air bubbles take some time to settle out. It can be difficult to bleed the air out when bleeding the brakes. Silicone fluid can not be used on vehicles with anti lock brakes.

I have been wrenching for years, and I have fixed countless cars with damage caused by moisture in contaminated brake fluid. I have had to free frozen pistons, and replace wheel cylinders, calipers and master cylinders due to rust and corrosion. I have also had my brakes fail due to the boiling point of the brake fluid being so low, that the fluid boiled resulting in the total failure of the brake system. Old brake fluid is extremely dangerous, as it can and will cause the brakes to fail without warning.

The ideal time to switch to Silicone fluid is when the rubber parts are all being replaced. Blow the metal lines out with compressed air, assemble the brake system and then flush with Silicone fluid until clean fluid comes out of the bleeder screws.

While somewhat expensive up front, if your car is a long term investment Silicone brake fluid will pay for itself many times over, saving you the cost of perpetual fluid replacement, the cost of repairs due to corrosion of brake components, and the cost of paint repair due to spilled brake fluid.


Please email all inquiries to: Dave
or snail mail
32 Turkey Hill Road
Richmond VT 05477

E-15 Ethanol – Dave’s Garage

By now you have probably been made aware of Ethanol, and the associated problems with it. We have been forced to buy E-10 for a few years now. E-10 is 10% corn based alcohol. E-10 is about 15-20% less efficient than conventional gasoline, resulting in a significant decrease in the miles per gallon. The alcohol in Ethanol is hydroscopic, it absorbs moisture. Once the alcohol absorbs all the moisture it can from the air, it becomes saturated, and the water falls out of suspension. This is called “phase separation.” When this happens, the fuel is useless and must be removed and discarded. This is of particular concern with older cars that have gas tanks vented to the atmosphere. The “shelf life” of Ethanol exposed to the atmosphere is only 3-6 months.

Although Ethanol has less energy in it than conventional gasoline, it actually burns hotter. This is a problem. Modern cars are now burning valves. This problem virtually disappeared with unleaded gas and hardened valves in the 1970s. Imagine my shock when my 2000 Chrysler minivan burned an exhaust valve.

This nasty brew is also very corrosive. Ethanol is a strong solvent. It will rot and destroy rubber components. Many fuel lines, carburetor gaskets, fuel pump diaphragms and gas tank sealers are not comparable with Ethanol. Remember that fuel tank sealer you used when you restored your car? That sealer is probably not Ethanol compatible. Rubber components will rot and be destroyed from the inside out (note picture to right). This damage will not be visible, until the part fails and begins to leak. A fuel line may look fine on the outside, but be rotted on the inside. Ethanol will combine with the dissolved rubber components, forming a gelatinous gunk and gum up the carburetor. Ethanol will also remove paint. Remember the moisture that is being held in suspension in Ethanol? Another nasty consequence of Ethanol is that water being held in suspension will rust metal components very quickly.

Ethanol is ok to use in Flex-Fuel vehicles. If your vehicle is a Flex-Fuel vehicle, you have nothing to worry about. How do you know if you have a Flex-Fuel vehicle? Your vehicle will say “Flex-Fuel on the side, have a yellow gas cap, or will have such identifying information in the owners manual.

How can this situation get any worse? Wait! It does get much worse! The government has decided to up the alcohol in Ethanol another 50%. What’s worse than E-10? E-15!

The government will flat out tell you not to use the mandated E-15 in vehicles manufactured before 2001; but that it is ok to use in Vehicles manufactured AFTER 2001.

However, (according to snopes.com) “several automakers and the American Automobile Association (AAA) have disputed the EPA’s claims, maintaining that E15 could damage fuel lines and void vehicle owners’ warranties in many cars, particularly vehicles manufactured prior to 2012:

Only 12 million of the more than 240 million light-duty vehicles in the United States are approved by manufacturers to use the gasoline, according to AAA. Automotive engineering experts believe that sustained use of the gas, both in newer and older vehicles, could cause accelerated engine wear and failure, fuel-system damage and false “check engine” lights for vehicles not approved by manufacturers to use E15, according to AAA.

The EPA recommends the use of E15 only in flexible-fuel vehicles and those built in 2001 or later, but critics maintain that even if E15 is safe for most or all cars in that class, many vehicles still on the road (up to 45% in some areas) do not fall within that class, and the newness of E15 means that many drivers could end up filling their tanks with the gasoline, not knowing it’s not approved for all vehicles.

“It is clear that millions of Americans are unfamiliar with E15, which means there is a strong possibility that many may improperly fill up using this gasoline and damage their vehicle,” AAA President and CEO Robert Darbelnet said. “Bringing E15 to the market without adequate safeguards does not responsibly meet the needs of consumers.”

BMW, Chrysler, Nissan, Toyota and VW have said their warranties will not cover fuel-related claims caused by E15. Ford, Honda, Kia, Mercedes-Benz and Volvo have said E15 use will void warranties, citing potential corrosive damage to fuel lines, gaskets and other engine components.

The AAA says the sale and use of E15 should be stopped until there is more extensive testing, better pump labels to safeguard consumers and more consumer education about potential hazards.”

Fortunately, Vermont’s congressional delegation are on the right side of this issue. Peter Welch is a vocal opponent of Ethanol; senators Sanders and Leahy have voiced opposition to Ethanol. The Obama administration, however, is actively pushing for E-15.

The only Silver lining in this mess is that the overall demand for gasoline is down, so there is less of a push to go to E-15.


Please email all inquiries to: Dave
or snail mail
32 Turkey Hill Road
Richmond VT 05477

Modern Timing Lights and Six Volt Electrical Systems – Dave’s Garage

This month we have a question from Wendell Noble. It seems his trusty timing light has given its last flash, and he wants to know what modern replacements will work with older six volt electrical systems.

There is no simple answer. Most modern timing lights designed to work with 12 volt systems will actually work on six volts. Some, how-ever, will not. For the ones that won’t, a 12 volt battery or a battery charger will have to be used. Timing lights take power from a battery, but the trip wire feeds from the number one spark plug wire.

I have several timing lights, from a 30 year old Sears timing light, a cheap Harbor Freight timing light and an Actron advance timing light. These timing lights will work on six volts.

My advise would be to take a chance and buy a new timing light and try it. If the battery is near the front of the engine, I would hook up the light with the positive lead going to the positive lead on the battery, and the negative lead going to the negative lead on the battery, and the inductive trip wire hooked up to the number one spark plug wire. Chances are, it will work on six volts. If it does not, then the positive and negative cables will have to be hooked up to a 12V power source, (either an extra battery, a battery charger or a 12 volt booster pack).

I have been impressed with the advance Actron timing light I bought through Amazon. It was inexpensive, and it works well. With this light, you only need to find TDC on the engine. The light has a knob on it to advance or retard the flash. If, for example, the timing specification is 8′ advanced at 2,000 RPM, the knob on the light can be set at 8′ advance, and then when the engine is at 2,000 rpm the timing will be correct when the light flash shows the timing pointer at TDC.

Of course, there is the occasional car that runs worse when timed according to the specifications. I have had to manually advance the timing a little bit at a time until I can hear engine knock, then slightly retard the timing until the engine knock stops.

As they say, timing is everything.


Please email all inquiries to: Dave
or snail mail
32 Turkey Hill Road
Richmond VT 05477

Packing Wheel Bearings – Dave’s Garage

Mechanical things need three things to work and work well. First, they need to be kept clean and dry, second they need to be properly lubricated and third, they need to be properly adjusted.

This advise is especially true of wheel bearings. Oddly, one of the biggest problems with wheel bearings can be caused by OVER lubricating them. The term “packing” wheel bearings has more to do with the application of grease than the quantity of grease.

To properly “pack” wheel bearings, the grease needs to be distributed thoroughly throughout the bearing assembly. The actual amount of grease needed is quite small. If too much grease is “packed” into the bearing and the cavity, this grease will be pushed out when the wheel spins, and could easily ruin the brake shoes. In addition, the wheel bearing could actually overheat.

Repacking wheel bearings is an easy job, and should be part of the routine maintenance of the vehicle. Before you decide to re-pack wheel bearings, make sure you have new grease seals and fresh wheel bearing grease on hand. If you suspect the bearings may need to be replaced, make sure you have them too. Make sure you have the proper parts before disassembly. Several VAE members can tell the story of how I purchased a set of trailer bearings assuming they are all the same size-They are not. Long story short, there are two sizes, and they are only 1/16″ different. By the time I realized this, the auto parts stores were all closed, and we were at the side of the road with the wrong parts.

wheel ball bearingBad wheel bearings have several tell tale signs of failure. They often make a humming, growling sound at speed. When turned by hand, they often make a “gravely” sound. There should be no axial play in the hub. Front wheel bearings that have failed will make a different sound as the steering wheel is turned. Generally, if the bearing sound goes quieter when you turn the wheel to the left, it is the right bearing, and if it gets quieter when you turn to the right, then it is the left bearing.

Oddly, a lot of newer cars do not have serviceable bearings, the entire hub needs to be replaced. I have noticed that these new hubs have almost no grease in them.

wheel bearing roller bearingTo repack a wheel bearing, first the spindle or axle nut needs to be removed. Often a puller will be needed to remove the hub assembly. If the cones need to be removed, a press will come in handy for removal. The grease seals will almost certainly be destroyed upon removal. The bearings and the hub need to be cleaned and dried. Kerosene and a clean paint brush work well to clean old wheel bearing grease. Once washed clean of grease, all traces of the solvent need to be removed. Soap and hot water work well for a final clean. Traces of solvent will destroy the wheel bearing grease. Once the bearings are clean and dry, they are ready for an inspection and greasing. Inspect the bearings carefully, looks for pits, scoring, rough spots or signs of overheating. Spin the bearing and listen for the tel-tale “gravely” sound. Feel the bearing as it rotates and feel for any binding or rough rotation.

If the bearing is reusable, it is time to pack and reassemble. Cleanliness is super important. Wash your hands and dry well. Take a dab of grease and place it in the palm of your hand. Push the grease through the outer race toward the inner race, getting grease through the rollers or the balls of the bearing. Once all the voids of the bearing are full, rotate the race a bit to evenly distribute the grease. Alternatively, a zip loc bag can be used to force grease through a bearing, or you could also use a bearing packer. I still prefer to do this job by hand.

Take your finger and put a smear of grease on the outer cone. Repeat this procedure for the second bearing in the hub.

Make sure you put a thin smear of grease on the lip of the new seal. The seal goes with the flat side on the outside, and the spring on the inside of the lip should face in. I use a scrap piece of 2 by 4 lumber and a mallet to tap the new seal in place. I have an oil seal installation tool, but I find the 2 by 4 works better.

tapered roller bearingReassemble the bearing/hub assembly. Do not fill the voids of the hub with extra grease. Once the assembly is together, tighten the spindle or axle nut. If there is a torque specification, torque to spec. If not, and it is a tapered roller bearing spindle, I tighten the nut until the bearing just starts to bind, then back off until I can install a cotter pin. You want to find the “sweet spot” where the wheel is loose, and also not binding at all. Too tight, or too loose and the bearing will soon fail. Feel the hub assembly and check for wob-ble in the bearing. Put the wheel back on and spin it a few times. Check for free noise free rotation, then check for wobble again. Place the dust cover on, and you are all set.

If done properly, the freshly packed wheel bearing should last a long, long time.


Please email all inquiries to: Dave
or snail mail
32 Turkey Hill Road
Richmond VT 05477

Plastic Welder – Dave’s Garage

Most home workshops have some type of welder. Whether it is a simple arc “stick” welder, a wire feed MIG welder, a modern TIG welder or a simple set of Oxygen-Acetylene torches, these tools are invaluable to a “Hands-on” automotive enthusiast.

Today, more and more things are made out of plastics. Inevitably, while working on a project, there will be a need to weld plastic. Unlike metal, plastic can not be electrically welded, as plastic is an insulator, not a conductor.

Like metal, plastic can be thermal-welded.This simply means fusing two similar plastics together with heat.

There are two affordable plastic welders available for the enthusiast. The most inexpensive type, is a hot air jet type. This type simply uses a jet of hot air to melt the welding surface and a plastic welding rod. This type of welder looks like a conventional hand held hair dryer with a metal cone tip at the end.

I have found this type to be particularly tricky to use. It is difficult to modulate the temperature, and the right temperature is critical for a good weld. If the temperature is too hot, the plastic burns, too cold and you cannot get a good bond.

The other option is speed tip welding, or airless welding. This welder looks a lot like a conventional soldering iron, only there is a slot in the tip for the welding rod to be fed into the machine. Speed tip welders have an adjustable heat setting, so the operator can “dial in” the proper temperature for the particular type of plastic.

I have both types of welders. I have used the speed top exclusively for the last several years, with very good results. I have successfully welded plastic interior parts, rubber bumpers, and many other miscellaneous parts.

I have a Urethane Supply welding kit. I bought my welder on Amazon for less than $200.00. It literally paid for itself the first time I fixed a bumper cover. They have much less expensive models starting at about $50.

This welder came with an instruction manual, welding rods and the welder itself, everything needed to begin plastic welding at home.

Like most welding, plastic welding takes a little practice. The right temperature is crucial. Too hot, you burn the plastic, too cold yields a cold weld with little strength.

As with metal welding, you have to use the appropriate plastic welding rod. It takes a little experience to be able to determine which rod to use with which plastics.

This tool turned out to be one of those tools that has proven to be very valuable, I can’t imagine not having it.


Please email all inquiries to: Dave
or snail mail
32 Turkey Hill Road
Richmond VT 05477