How would you do "this"

[gerard]

Since my hands on experience with CNC is extremely limited, what better way to better understand, than to ask questons, that be said, my hopes are that I can drag everyone in with a technique to share.

the project I am contemplating in my head is one that I have done many times withhand tools, so I pretty much understand the actual task, how would you create the following with a shopbot, and how long do you feel it would take to create the actual files needed, and how long would the setup and cutting times be in your situation, based on your own setups.

the project is a basic A frame similar to the side of a sawhorse made out of 2x4 stock, each frame had a spread at the base of 18 inches,and a height of 31" at the top, the two legs are lapjointerd and the top of the frame is flat, so as to support another 2x4 there is a 2x4 member lapjointed roughly 12 inches from floor height so as to make a frame that looks just like the letter A.
As Im not specifically asking for a cutting file for this as much as Im curious to know how you might go about it, the entire project is open for personal interpretation, so kick it around, and share with me as well as all of the other newbies how you might go about this project.
thanks in advance guys.

[harryball]

It would depend on how many I needed to make... if I needed just a few I would use my radial arm saw with a dado etc...

If I needed many of them and was going to make a bot project out of it, I would create a high vac jig with a gasket to hold 2x4 blanks in place and run using a 3/8" cutter. Attention would have to be paid closely to positioning issues since you are using the entire 2x4... otherwise I might cut the entire part out of a 2x6 and just let the waste fall where it may.

Robert

[beacon14]

I would draw the frame in DesignCad, then (still in DesignCad) copy each part into the position in which I will have the parts on the table. With my 2-Fein vac table I can hold down 2x4's if they are reasonably flat by masking the rest of the zone with 1/4" scraps. (For a nicer frame and better hold-down I'd pass them over the jointer and through the planer first). I'd separate the 2x4's on the table with some strips of scrap since you'd want the pocketing toolpaths to run past each part slightly. The spacer strips would be included in the Designcad drawing.

Then I'd draw the areas to be pocketed in DesignCad on a separate layer, extend them slightly past the part edges to account for the bit radius, export them into VCarve Pro and use a pocketing toolpath to create the ShopBot file.

I'd also offset the cutlines that will create the end cuts you need by 1/2 the tool diameter and also extend them slightly. I'd export them into VCarve as well and use a Profile toolpath with Machine Vectors "on" selected. I'd probably keep my passes to 1/4" deep or so.

However, you will have to flip over at least one of the three parts or the half-lap joints won't work out. I'd draw the flipped part separately, aligned with the edge of the table for reference, and create a separate toolpath for it.

I'd expect the whole process to take about 15 minutes, including drawing the frame. About the same amount of time it took to write this description.