G-Fab techtips: Hole-E Mole-E

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So I thought it’d be a good idea to share some techniques I’ve learned over the years. Simple, easy to follow tips to help maximize your full potential while welding or fabricating your projects. So enjoy this post, as well as more to come, and see if we can help give you that different angle.

I would first like to talk about how to achieve nice and neat fitments between parts and through holes that they must line up with. Now I know many of you out there may have dealt with drilling holes, big or small, with the intention of welding some type of tube or fitting that it must line up with. I’ve been there before only to have the loose part move due to myself bumping it right before tack welding it, or the shrinkage of a tack as it cools. This can also pull your part off center a bit. Another annoyance is having a hole too large causing your part to sink in, making it a little harder to square up. I have come to my own conclusion for a technique I will always use as a first resort. Now on to the process.

For my example, I will be finishing up an intercooler I am currently working on where the inlet tube must be welded to it’s endtank. After having the tube-end bead rolled and all burs cleaned up, I place the part where I’d like it and proceed to weld it to the tank without drilling a single hole. This will ensure your part is as square, as when you fit it. Also, the weld will lay evenly all the way around because the material is consistent. Sometimes poor fitment of a pre-existing hole may cause the material to heat up faster in some areas and cooler in others. This could potentially cause you to adjust your amperage mid weld, making it harder to be consistent.

Once welded, it’s time to bust out the holesaw kit. Now, in my experience, I’m able to use a holesaw that is a 1/4″ smaller than the O.D. of the tube it must slide in to. The tube will act as a guide for the hole saw, eliminating the use of a pilot drill. So be sure to clamp the endtank down and carefully cut your hole.

Now that the hole has been cut, a quick clean up with a carbide bur or cartridge roll (barrel roll) can kick you off to the last step.

If you’ve followed correctly, a clean even hole will give you a good chunk of aluminum to work with on the inside. I just aim my torch at the inside edge and foot pulse the corner giving you that smooth edge and the satisfaction of knowing the part is welded inside and out.

So there you have it. Now go use it.

Thanks for reading and stay tuned in for the next tech tip to follow.