Project3 Part 2

This is turning out to be a super fun little project!

Made some good progress. A lot of the parts are in, still waiting on the motors from OMC, and I just ordered the gearing (yikes those are expensive) from SDP-SI.com

The Aluminum extrusion is simple 1 inch x 2 inch stock.  It will make a nice lightweight frame for little cost. All I did was cut a couple pieces off, I sort of just guessed the length. About 6 inches on the vertical, 5 on the horizontal.

Cut it with a standard miter saw using a blade intended to cut metals. I wrecked one of these blades once when handholding a 2 inch thick piece of aluminum stock while cutting through it. Damn near gave me a heart attack, it sounded like a gunshot.

Anyway, the point is, use a good aluminum cutting blade and you might want to spray some wd 40 on it to lubricate it and help cool the blade.

Using a diablo blade on a delta saw. The blade runs about 60 bucks if you dont have one. Do NOT try this with a wood saw.

Next up, I had to make holes for the bearings. I used a Dewalt 1-1/8th bit hole saw from amazon.

This was simple enough, marked the spot I wanted the holes, then using a small bit (smaller than the pilot hole portion of the dewalt bit) I used my drill press and put it all the way through the stock to create some guide holes. I then drilled out the larger hole with the dewalt, flipped it over and hit the other side. You REALLY need to do this with a drill press. Hand holding it will not work. Also be use to use some WD40 to lubricate the stock as the hole saw cuts, and be sure to clean the shavings several times while cutting through.

Gotta use a drill press for this part. No pilot hole in this pic, but I forgot to take pics while I did it. 🙂

So now i have the holes!

Next was to test the fitment of the bearings, and sure enough they fit pretty well. it is not a snug fit, but there is very little room for them to move. I might put a small ring of tape around them just to help make them nice and snug. Maybe.

At this point I was fairly excited about how everything was going, but did not realize that shit was about to get soooo much cooler. I was trying to find out the best way to join the parts. I was suspecting I would have to get an aluminum block and drill and tap some holes to get them joined up. Then I found an awesome video on youtube that shows how to weld aluminum with a blow torch. Dont worry, the torch can be had for about 25 bucks. And you will need some aluminum brazing rods. Go hit youtube and look for welding aluminum with torch and you will find various videos of this technique. 

First step is to bevel the edges a bit to create a channel for the aluminum. it aals roughs it up a bit for a more secure grip.

Next you need to clamp the parts together the way you want them. I did not have a clamp with large enough jaws, luckily there is a Harbor Freight a few miles for my house for super cheap throw away tools. This clamp only cost 3 bucks.

Next I secured it in a vice clamp to hold it while I heated the stock.

This part took a while. The videos all say it takes about 5 min.  the idea is to get the stock so how that when you touch the brazing rod to it that it instantly melts and runs down the channels. I did test this out on a couple pieces of aluminum to have at least one test run under my belt before the real deal. It took about 3 min to get it hot enough

Once the metal is hot enough, just touch the brazing rod it it and it melts and fills in the channels.

its not super pretty but far nicer than I had expected for my 2nd time trying this sort of thing.

Then back to the grinder to remove the excess welding. Be sure you give it a good 10 to 15 minutes to cool before you try touching it.

Using a file for a little extra cleanup.

And here it is!  Bearings and posts back in place, it looks fantastic 🙂

Playing around with it a bit. The gears and belts are en route, as well as a few part modifications I had to make. Once I have those parts in i can make the final fitment and weld on the motor mounts and work out the base. Then I will take everything apart and get to paint. I had originally wanted to go with Fire Engine Red , but after some consideration I have another idea.  I’ll have to take the CNC Slider apart as well, might as well try to make everything match and look nice.

I can’t express how excited I am about this project. I never knew you could weld aluminum this way. I suppose a tig welder would probably give a better bond, but this is more than solid enough for my uses. This newfound ability is really going to be beneficial for me moving forward. I am already thinking about the next robot I am going to build. I am considering some sort of a crane or something next.

 

 

2 thoughts on “Project3 Part 2”

    1. Not exactly sure to be honest. There are no datasheets listed from servocity. I have the part linked under Project3 under the Robots menu.
      This is all they have on it.
      Material Stainless Steel
      Length 0.312″
      Inside Diameter 0.500″
      Outside Diameter 1.125″
      Flange Thickness 0.062″
      Flanged Diameter 1.23″

Leave a Reply