How to Build a Tube Bumper

How To Build A Tube Bumper

well Ive got alto of requests to wright an article on how to build a tube bumper. I know most people are going to want help on how to build a front bumper but all i have at this point to show you is a rear bumper. Ill have a front bumper up as soon as possible. But in any case you can get a lot of info off this article to be able to build a front bumper if you cant wait.

So im gonna give it a shot and tell you how i know of the fastest and easiest way to build one. of cores each bumper is going to be different depending on what vehicle its going on, but it doesn’t matter because the techniques are all the same.

Ok so lets start off with what your going to need to build this bumper:

  • Some sort of tube bender is necessary. We use a hydraulic tube bender but
  • A welder.
  • A measuring tape and permanent marker.
  • An angle grinder with flapper disk, belt sander etc.
  • If you are using a angle grinder your going to need a vice or something to clamp down the tube to stop it from moving.
  • A chop saw, band saw, saws-all etc. something to cut the tubing.
  • your going to need at least two big adjustable jack stands or something to support your main tube.

Measurement and prep

First off your going to want to have some one help you take a measurement for the main bumper tube. bend the tape mesure on both sides where you roughly want the bend’s to be.

Then your going to want to add 3-5″ extra to your main tube measurement so the bender can get enough grip on the tube to bend, and also just incase theres a mistake made.

once you have the tube cut find the center of the over all length and mark it all the way around. one way to mark it evenly all the way around the tube is with a collar tube. Witch is a tube cut straight, and that is one size bigger than the tubing your currently using.

once you have found center on the tube then try to find center on the vehicle and mark it. As you notice we’ve made a custom hitch to span the frame rails. You can also do this or just cap off the frame rails with plate or fit a tube  in-between them, instead of the tow hitch configuration we did.

Now you want to sight, to match the bumper’s lines to the body lines of the truck, If the vehicle isn’t level, and the bumper is, then the bumper will

look crooked.Build the bumper to match the body lines. So sight the tube to the truck (not the ground) as you can see in the picture we have made the tube match up with the line of the tail gate.

Bending the main bumper tube

Once you have that done you can plot out where your going to want the bend start to be. you can do this a couple ways one if you can guess where the bend is going to start and bend it a coupe times Intel you get the desired bend ideally matching the bumper’s radius to the body panel radius. You can also bend a sample piece of tubing (mark where the bend start is on the sample tube) then bend it and remember what degree it was bent at,  place it on the top of the main tube and mark on the main tube where the start of the sample piece was. Then bend the tube the same at the same degree that your sample piece was bent at. Check it make sure it still lines up with your center lines and bend the other side.

Once your main tube is bent up level and square to the vehicle then your going to want to fit your two tubes to the frame, hitch or tube. so take a measurement and  cut and fit your two tubes. Then tack weld everything together.

Tack welding Tip

A good rule of thumb is that your going to want to tack weld at least three tacks on each notched piece of tubing, plate etc..

You do this to prevent from the part from moving or breaking tacks when your welding, because it happens frequently.

When you tack the parts try and tack where your weld stops and starts are going to occur so your not welding over a big lumpy tack welds.

Bottom bumper tube

now we can start building the bottom tube that helps add strength and helps tie everything together. So were going to start off by taking a measurement the same way we did earlier but since the bends are not as close to the end of the tube we don’t have to add the 3-5″ to the part. But we do need to add around 1-2″ (depending how comfortable you are with notching tube) to compensate for the material that were going to grind or notch out for the tube to fit nicely to the top tube.

  • Cut your tube to your measurement find center and mark it all the way around.
  • Then get a measurement from the bottom of the top tube to the inside or top of the bottom tube your about to bend.
  • Then measure the outside point where you want your tube to hit on both sides.
  • Keep those measurements for drafting.

Drafting your bumper

Now comes the fun part your going to want to draft out your bumper on a table or the ground. (looking straight ahead as if your were squatted down. Not from the top down) marking all the lines needed to make everything match up the way you want it, and knowing where to start the bends and how far to bend them. Your going to want to mark:

  • The center line of the tube.
  • Where you want your tube to land.
  • The bend start line.
  • where the top main tube is, and where it is in relation to the top of the tube your bending/ fitting now.
  1. Start by making a straight line or use the edge of a table.
  2. Use that line as your pretend main tube, find and mark your center line.
  3. Then take your measurements you just took and start plotting your other lines.
  4. Measure from Line #1 to  line #2 and draw your straight even line.
  5. Then from line #2 to line #4 and draw it out like the picture below.

Once you have it all drafted out your going to do something similar to the bend section above. the easiest and most precise way to do it  bend a sample piece of tubing  and use that as a reference (mark where the bend started and be sure to make the tube long enough to hit Line #1 & #4 in the picture)

  • Estimate where the best place is to put the bend.
  • Then, bend the tube little by little and line it up with Line#2 and trying to meet up with Line #1 & #4 with the cut end of the of the tube, Intel it lands in the right spot. Remember always line it up with the Center line and Line #2 while checking it.
  • You can use a 90 degree square to make sure it lines up with Line #2.
  • Once you have the one side bent, then mark where the bend start of the bend is on the table.
  • Then measure from the center line to the bend start line you just made, and mark it on the other side of the Draft drawing
  • Now line the tube back up with the lines and mark your bend start line on the UN bent side of the tube
  • Now you know where to start to bending the other side of your tube at. So just bend it to the same degree as the other side and your set.

Notching

Now that you have bent both sides its time to notch the tube. You want to place your tube back on the drawing and where the tube hangs over Line #1 your going want to mark a line on the tube parallel with Line #1 and cut the tube  about 3/8 – 1/2″ longer, and start notching and fitting.




Since the bottom tube is so long and awkward you might want to consider using a vice to hold the tube and an angle grinder with a flap disk to help in notching it.


 

Finishing touches

We added three more tubes on the bumper to strengthen it, and ad to the design.

after that we cut off the excess tubing with a saws-all to keep from snagging and to give it a cleaner look. you might want to cap off the end with a peice of plate to keep the tube from rusting inside and to make it look finished.

after every thing is all fit, weld it up and enjoy.

you should hopefully be able to design any style rear bumper how ever you like with the information ive given you in this article. if you have any qustions at all or have missed something i would be more than happy to answer them to the best of my ability.


 

 

 

Dont forget to leave a comment and to subscribe to my mailing list if you like this article thanks,

Flynn.


4 Responses to How to Build a Tube Bumper

  1. M . M. Kzr says:

    thankx for put’g me on email’g ; up dates

  2. aaron says:

    i have heard that u need to use a mandrel bender so the tubing stays strong and does not crease, your thoughts

  3. Flynn says:

    Hey Aaron, yes mandrel bent tubing is the way to go. a mandrel bender holds the tube in place while it rolls the bend into it. A regular pipe bender doesn’t roll the tube it just presses it around a die therefore putting kinks or “creases” in the tube and un-evenly stretching the outer surface of the tube. its also virtually impossible to nicely bend thin wall tubing.

    thanks for the comment Aaron,
    Flynn

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