Notching 2" tube by hand

[branimal]

Part of my Jeep's aftermarket front bumper is rusted out and I'd like to replace it. The bumper is 2" round tube and I found some 1.8" tube being thrown out.

Plan is to take the bumper off and cut out the bad section. Next I'd have to cut a 45 on one end of the new tube and notch the opposing end. How can I template that notch?

Gonna weld it together, but my my welding skills are not that great. Can I use Bondo for metal to plug the gaps I wont be able to fully close?

Thanks.

 

[firebirdparts]

If this is a one-off, then I guess you use a grinder and test fit it until you like it.

 

[Hank11]

You can make a wooden guide for a hole saw to make one or two cuts like that.

 

[Walkers]

Look up chop saw tube notching. It is not tough, the are charts showing the angles needed.

 

[Jswain]

If you're welding skills are that bad that you're going to use Bondo to fill the gaps I wouldnt be too worried about getting a perfect notch.... Haha JK

Cut it a couple inches long and use a grinder to notch it, take a bit off check etc. Once you get the notched end cut then cut the angle for the other end, slightly long as well then grinder down to fit. The better the fit the easier it will be to weld

 

[nadogail]

If you can find the welding rod that works best for you and adjust your welder for the right heat you will be half way there.

If you can find some plastic pipe you can practice notching and fitting cheaply.

 

[BillK]

I have done it a few times. Just cut it close with a hacksaw and then use a grinder or even a round file to get it the rest of the way. Time consuming but not really that hard. You should be able to get it close enough that you wont have gaps when welding.

 

[txvwnut]

Figure out the angle needed to fit against the tube then cut it. To make the notch cut the point off the tube then fit the length against the plate.

 

[Jackfre]

I think I’d use a hole saw slightly undersized and then use a rotary file to enlarge it until you hit the right fit-up. With not great welding skills the closer you can get to a good fit the better your welding will be. You get a wonky hole cut and have to try to fill it and it can turn into a flown car in a hurry.

 

[Half-fast eddie]

This has been around since forever.

 

[The Cobbler]

an angle grinder is probably already in your arsenal and will make short work of your task

 

[rawen2]

Here's an online calculator that lets you print out a pattern to wrap around the tube. Then just cut along the line.
I used it years ago to attach a pellet stove exhaust into an existing wood stove pipe. It worked great.

Tube Coping Calculator

 

[goldtang]

Cardboard is you friend. roll up a piece to the diameter you need and use tape to hold it together , trim the ends to suit we’re you want it to fit Then wrap it around the tube you are going to use then use a angle grinder etc to trim the ends of the tube (CAD) cardboard aided design found oil board/ Stencil board is best but an cardboard will do

 

[dcg9381]

https://www.blocklayer.com/pipe-notch.aspx (print a template)

 

[branimal]

Looks like there are a lot of ways to skin this cat. I'll give the hole saw idea a try if not I'll go with the tube coping calculator template. I have a enough round stock to try this a few times to get it right.

Thanks for all the advice.

 

[05snopro440]

If this is something you'll do somewhat regularly, buy this. If not, make a basic one yourself.

https://www.summitracing.com/parts/...PqjL9C6AdWkuooSgQXJr9ffDdD5ccVxBoCw8wQAvD_BwE

And no, please don't use bondo to fill the gaps. Get the fit tight, and fill the holes and gaps by welding.

 

[CraigStu]

The couple of times I have had to do this I found that a bench grinder was a big help. I happened to have an old grinding wheel that the surface had gotten rounded off a lot. I had replaced it because I usually want a flat surface, but fortunately I had not thrown it out. So I made cuts w/ the bandsaw that were kind of close to what was needed and rounded them out on the old grinding wheel. Nice part about what you are doing is that the diagonal tube position isn't too critical. So you can mess it up some, and then fix it, and all that happens is the diagonal moves a little further into the angle.

 

[Half-fast eddie]

And no, please don't use bondo to fill the gaps.

Everyone knows JBWeld is preferred.

 

[Sumboodie]

Online template and cut with torch or plaz

 

[Jeffh555]

Look up chop saw tube notching. It is not tough, the are charts showing the angles needed.

This is the way. Even if you don't have a chop saw, you could use the same technique with an angle grinder or other metal cutting tool. I've built bumpers and cages this way with an angle grinder.

Hole saw won't work unless you have a rigid way to hold it (like a tube notcher, mill, lathe (clamp the tube to the cross slide), or beefy drill press (questionable on this one)

 

[slowtwitch73]

Yeah online template.. it prints the cut line and you wrap/stick/transfer it to your tube then use whatever method to cut/grind to it.

But I would just cut a triangular plate to fill that area...easier to weld, and better chance wont need filler.... also check the other tubes to make sure they aren't compromised as well.