Warbird Information Exchange

Hello,
Now that I have been able to source the extrusions that I need, I have a new question. Obviously the most correct and accurate method of cutting and shaping aluminum extrusions is a mill. However I was wondering what DIY methods WIX members have used on their projects. I have looked into "drag saws" and "cold saws" as a way of cutting the material (really just a fancy cut off saw). I have also considered a circular saw or even a jig saw, none seem to be accurate or safe for this application. One example is to machine/taper down a 1" section to 3/4" as shown:



I want to use a safe method to produce an accurate cut. I have thought about buying a small manual mill for my prototype work. I have alot of extrusions to cut for my project so I want to establish a good process early on. I look forward to thoughts/suggestions of the group.

I would say a band saw with a good metal cutting blade would work the best for one off parts. It is also useful for many other cutting operations.

Randy

You can also build simple jigs out of wood to vastly improve the accuracy of your cut. In the picture you showed, you can bolt or clamp a piece of wood 1 inch from the saw and run the extrusion vertical along the piece of wood, so it maintains 1 inch from the blade. Then move the wood in to 3/4 and run the extrusion to the point of your taper. Then, you just have to cut the correct angle between the two line cuts. Hope that makes sense. Be careful of temperature - take your time.

How about a wooden guide and a router to make the cut?

We use Dotco high speed air driven routers with two flute fast spiral endmills to trim panels up to .125" thick at work. Any router that you use should be capable of very high speeds and cut depths need to be quite small. Standard design router jigs like what you would use for woodwork work quite well. Make darned sure that you keep your hand and fingers well clear of the bit as if you get into it, meat will dissapear in a hurry.
If the cut isn't very long and is simply a straight or taper cut, you can clamp the piece up and use a 12 or 18" curved tooth body file to take the material down. Use long, steady strokes with light to moderate pressures, with the file angled slightly so that your hands can clear the material. Good cuts will show as a very shiny surface. Prussian blue can be used to dye the area and find low spots. If you need to touch up the surface a little, switch to a double cut mill bastard file and clean it often.
I've used the files almost 90% of the time when fitting panels or repair pieces and can trim most panels with the files a heck of a lot faster than setting up a router or going to the belt sander.

Cvairwerks wrote:We use Dotco high speed air driven routers with two flute fast spiral endmills to trim panels up to .125" thick at work. Any router that you use should be capable of very high speeds and cut depths need to be quite small. Standard design router jigs like what you would use for woodwork work quite well. Make darned sure that you keep your hand and fingers well clear of the bit as if you get into it, meat will dissapear in a hurry.
If the cut isn't very long and is simply a straight or taper cut, you can clamp the piece up and use a 12 or 18" curved tooth body file to take the material down. Use long, steady strokes with light to moderate pressures, with the file angled slightly so that your hands can clear the material. Good cuts will show as a very shiny surface. Prussian blue can be used to dye the area and find low spots. If you need to touch up the surface a little, switch to a double cut mill bastard file and clean it often.
I've used the files almost 90% of the time when fitting panels or repair pieces and can trim most panels with the files a heck of a lot faster than setting up a router or going to the belt sander.

Absolutely right on. I have used a router for years, even with a radius carbide cutter to round corners of plate. I use WD40 as a lube. Lay out well the finished size, cut big, file and massage to size. I use bees wax on the sharp files (file card helps clean the m frequently), burr knives, etc.

Evreyone's input here is applicable, depending on your equipment and determination. I once built a tube frame dirt car with bench grinders with varying radius wheels, files, and an "always on" TIG welder. Shock! Literally if I was touching the frame when changing my tungsten...