Installing Inverted Flare Fittings

Inverted flare fittings are also commonly known as 45 degree double flares, and were used for automotive applications (brake lines) in almost all vehicles manufactured from the 30’s to the 80’s. In reality, an inverted flare fitting is a single nut which uses a 45 degree double flare, and is lapped over, so that the brake tube’s end has double the thickness. These flare fittings and their installation tools are easily and widely available and therefore, are relatively cheap to purchase. It is worthy to note that inverted flare fittings are significantly different from a 37 or AN flares.

Using the tips and recommendations below you can easily install inverted flare fittings appropriately.

Tip 1: Choose the Right Tube

For your installation to run smoothly, and your fittings to work effectively, it is important to understand as well as choose an appropriate tube, as many different forms with varying grades/thicknesses are available in the market. Your choice and application of the tubing material will allow you to flare the tube. Note that automotive tubing is the least thick tube available, whereas thicker tubes, which are obviously harder to bend are also available. 2 forms, namely steel and stainless tubes are accessible with the stainless one with higher resistance to corrosion.

Tip 2: Do your Prep

Your preparation for the project involves getting the most appropriate tools, getting your inverted flare fitting ready for installation. Getting the flare ready involves cutting the tubing, with the help of a wire fiber wheel.  Don't use a tube cutter, as it causes problems of material hardening and of the edges rolling. See to it that you remove the burr created when you cut the tube, and that you use a drill or a center drill for the inside edges.

Tip 3: Measure the Tube Right

Once your preparations are complete, remove the material from the inside and outside so that it folds easily once you start flaring. Proceed by advancing the prepared tube through the die block, so as to bring it to the height of the appropriate button. Use a side clamp for holding the tube and position the button along with the pin found in the tube. Then, line the tool over the upper top of the button. Clamping the tube, turn the handle until the button die reaches out to the die bar. Once the button die meets the die block, remove the button die, ending your procedure by tightening the handle again. See to it that you don’t over tighten the tool.

Tip 4: Inspect your Installation

Once your installation processes is complete, assure that you did not use a tube cutter, avoided tube slipping, did not allow for a shallow flair, which is created if sufficient material is not stuck up through the block, and did not over tighten the tool used for the buttons for the double flair, so as to assure that it did not break or get damaged.