Walking Beam Conveyor

[Brian Rupnow]

I may go a bit "steampunk" on the drive for this walking beam. I have a beautiful pulley and a set of gears that I made a few years ago for the marble automation machine that never really got finished. Walking beams, by their very nature should run at a slow pace, and they will benefit from the gear reduction torque multiplier as well.

[Brian Rupnow]

This was a big job. Thank the Lord for bandsaws and belt sanders. I think this is going to become very interesting---

[crueby]

Brian, how did you make that gear with the brass teeth but (steel, aluminum, something else) center? Press fit, held by spokes, heat/freeze method? It looks really good.

[Brian Rupnow]

Brian, how did you make that gear with the brass teeth but (steel, aluminum, something else) center? Press fit, held by spokes, heat/freeze method? It looks really good.

Slip fit and 638 Loctite.

[b.lindsey]

Another interesting non-engine project Brian...larger than I was expecting too. Should be a fun one to watch.

Bill

[Brian Rupnow]

Bill--Nice to hear from you. I'm surprised at the size of this thing too.---it seemed smaller on the computer screen. Ha Ha ----Brian

[Alan Haisley]

Brian,
It looks like the idea is that the beam will move slowly. Had you considered either a Geneva drive or something like an elliptical gearing so that the parts move more quickly from station to station but then are at each station for a longer time?
I suppose that ideally the conveyor needs to be made so that the part moving time is independently adjustable from the on station time but I can't get my head around a mechanical system to do that.
These days you could just build a computer controlled machine but in the spirit of what you are making that would be cheating.
Do you suppose that some of the "507 Mechanical Movements" were meant to drive a conveyor like yours?
  Alan

[Brian Rupnow]

Alan--we are talking old school automation here, circa 1950's. The walking beam moved at a constant pace, and was timed to enable the slowest operation performed at one of the stations to complete it's cycle and then retract out of the way before the walking beam moved the parts again. It was slow, and not particularly efficient, but it worked night and day, 24 hours around the clock, never took a lunch break or a pee break, and never called in sick.---Brian

[Brian Rupnow]

This morning I put all of the half round slots in the stationary part of the walking beam. I first gashed all the cuts 0.188" deep with a 45 degree chamfering tool. Each slot took 3 passes, one at .062" deep, then one at 0.122" deep, and a final at full 0.188" deep. Then I put in my 3/8" ball nosed cutter and took full depth 0.188" cuts in two passes , one pass for roughing and the second just to bring the table back and give a bit of a finishing "burnish" to the newly cut half round. I did it this way because ball nosed cutters really don't like to move a lot of material during a cut.

[Brian Rupnow]

That went well!! I think that the pieces in the picture are the pieces with the most work in them. From here on in, I think most of the stuff is fairly simple.

[Brian Rupnow]

Crueby--You can see the full build of that big brass gear with the steel spokes starting at post #61 of this thread.---Brian
http://www.modelenginemaker.com/index.php/topic,2566.60.html

[Roger B]

Very nice      Following along in the background.

[crueby]

Crueby--You can see the full build of that big brass gear with the steel spokes starting at post #61 of this thread.---Brian
http://www.modelenginemaker.com/index.php/topic,2566.60.html

Nice, thanks!

After reading your comments about how big a gear it was, I just have to mention the 6-3/4" diameter, 240 tooth one on my Corliss flywheel, cut on my little sherline mill and rotary table. As others mentioned, the turns and stopping points were precalculated so there was no accumulated error. That many teeth to cut is nerve wracking, one miscount and its done. Though yours with the steel core looks much nicer!

[Brian Rupnow]

I couldn't buy 5/16" cold rolled flatbar, so I bought a piece of 3/8" instead. This is destined to become four 2 3/16" diameter  "cams" that fit into the big holes in the side of the walking beam. I have a 2" diameter carbide face mill that I have used very few times, so tonight was the time to try it on the steel flatbar. This was a new experience for me. Someone suggested that I take a full 1/16" deep cut, but I just couldn't bring myself to do that. My mill is a fairly big tabletop model, but it's not a Bridgeport. I took three .016" depth cuts and one .014" deep cut, all at 500 rpm with lots of 'squirt on" cutting oil. The mill handled it alright, but it groaned a bit when I took the cut at the "shoulder" at each end of the bar. I expect that the flatbar will "banana" a bit when I take the toe clamps off, but that doesn't really matter for what I'm going to do with it.

[b.lindsey]

Coming along well Brian. Maybe I missed it...what are you planning to convey? 

Bill