Model Compressor---Maybe

[Ghosty]

Brian,
Looks great, another gismo to run.
Merry Christmas to you and yours from me and mine.

Cheers
Andrew

 

[Brian Rupnow]

And here we have my final video for 2017. It shows the scotch-yoke compressor being driven by my overhead cam engine, thru my cone clutch. The compressor was a fun little "no stress" project and it gives me one more unusual thing to drive with my model engines.---Brian Rupnow
[ame]https://www.youtube.com/watch?v=aOkTT83o_Vs&feature=youtu.be[/ame]

 

[ShopShoe]

Brian, I really did enjoy it. I have a semi-built hand cranked balloon compressor sitting in my shop which I will get back to some day. I have to make a new cylinder and piston because the volume of air it pumps is too small so it takes too long (Terribly Boring, You Bet.)

I enjoy all your little gadgets and your engine builds and hope to make some in the future.

Thank You for posting,

--ShopShoe

 

[Brian Rupnow]

Thank you, Shopshoe. Mine would work better if I changed a pulley and sped it up a bit. People want to see the balloon pop.--I'm always glad to hear from someone who takes a bit of pleasure from what I post.---Brian

 

[stragenmitsuko]

There was a videogame once it was called the incredible machines or something like that .
You had to combine all kinds of gears and belts and various mechanical parts to make a certain movement happen . There was a mouse in a wheel as a power source , and if I remember it right there was also a balloon that would trip switches when released .
Somehow this machine of yours reminds me of that game .

Keep up the good work , here's another one who enjoy's your builds .


Pat

 

[Brian Rupnow]

Thank you Pat. I was looking around this morning for something to make a smaller pulley out of for my clutch, to speed things up a bit. Everybody across 3 forums want to see the balloon pop.---Brian

 

[Barnbikes]

Figure out a very slow rising arm with a pin in the end.

 

[dsage]

Hi Brian et.al.
I'm wondering why the videos you've posted only show as a black screen for me? (like a black picture). Nothing happens when I click on them and I don't see a link embedded in the frame.

 

[Brian Rupnow]

DSAGE--I have no idea---sorry.

 

[Brian Rupnow]

It's New Years day here, and having survived Christmas in grand style, I'm down on my computer playing. I would like to have the balloon blow up twice as fast as it currently does. I can either run the compressor twice as fast---or---Make each cylinder double acting. They are only single acting right now, with one end open to atmosphere. However, there is an alignment issue which caused some pretty severe binding between the aluminum pistons and the inside of the cylinder. I got around that by making a nylon piston 0.010" undersize and putting an o-ring on it. That same alignment issue would no doubt cause a "bind" between the cylinder rod and a rod end endcap.--Unless--I found a way to make an air-tight seal that still avoided metal to metal contact. I think what I show in the attached drawing would work. Make a 0.030" oversize hole in the metal endcap, then add a rubber o-ring with 1/4" i.d. (actually they are a bit less than 0.250"), and hold the o-ring in place with a Loctited brass sleeve. This will serve to keep an air-tight seal, but still allow enough clearance to prevent metal on metal binding. I will have to think on this for a bit.

 

[Ghosty]

Hi Brian et.al.
I'm wondering why the videos you've posted only show as a black screen for me? (like a black picture). Nothing happens when I click on them and I don't see a link embedded in the frame.

dsage,
Right click on the black, open properties, copy Address(URL) and paste to your browser bar. Google wants every one to use their Chrome browser, when you open y-tube, you will see the blue bar across the top of the screen with this in it.
(Watch YouTube videos with Chrome. Yes, get Chrome now.)

Hope this helps,
Cheers
Andrew

 

[Cogsy]

Hi Brian et.al.
I'm wondering why the videos you've posted only show as a black screen for me? (like a black picture). Nothing happens when I click on them and I don't see a link embedded in the frame.

As Ghosty says, it's a browser issue. Something with the forum software not liking IE anymore (now that IE has been officially retired this will happen with more and more sites over time). Chrome will fix it, as using other modern browsers as well. I'm not a huge fan of Chrome but something tells me I'll have to switch to it at some point.

 

[dsage]

Thanks. I was on the right track but hadn't dug as far as Properties to find the URL. Usually there is a "copy URL" in the right click list.
Shame about IE. I wasn't aware it is obsolete.
Sorry for the distraction.
At least now I can have a look at Brian's wonderful machine in action.

Thanks
Sage

 

[Brian Rupnow]

So, here we are, two days into the new year, and I've eaten too much, rested too much, and read too much. It must be time to machine something. The cylinder rod end seals that I designed yesterday have become reality today. Before I Loctite the brass sleeves into place to lock the rubber O-rings in place, I thought I should put up a picture. After they are assembled, you won't see anything but the cap plates.

 

[Brian Rupnow]

Of course nothing is ever easy. Since I already have my existing valves and manifold J B Welded in place, I am going to have to build a valve set-up that both sucks and blows from a common port in the side of the new rod end caps. This will be tied in with flexible hose to the existing manifold.

 

[Brian Rupnow]

Everything went together as I had planned. It's close,--very close, but the yoke clears the end caps by about .030" at full stroke. I still have to make the valves that fit onto the two visible pipes sticking out from the side of the caps. I'm very pleased (and somewhat relieved) that everything goes round and round without any serious interferences.

 

[Brian Rupnow]

The compressor is approaching the limits of what can be driven by a rubber o-ring drive belt. If cogged "timing pulley" drives weren't so horribly expensive I would use that to drive it. (The single set of two pulleys and a 3/8" wide belt as used on my overhead cam engine cost over $100 when shipping was factored in.) I am currently tossing around the idea of using a #25 pitch roller chain and sprockets. A "standard" old style bicycle chain is #35 with 1/2" center to center of rollers. A #25 pitch roller chain is 3/8" center to center of rollers, and a #25 sprocket is 1/8" wide. There is one size smaller of roller chain, the #1475 pitch series which is .1475" center to center of rollers and takes a 1/16" wide sprocket, but my gut tells me that is getting a bit too small. I will call Canadian Bearings tomorrow and get a price on the #25 pitch chain and sprockets.

 

[Charles Lamont]

A Poly-V belt is cheap and should be available from an online supplier. The pulleys are not difficult to make.

 

[Brian Rupnow]

Charles--I had to Google "poly v-belt" to see what it was. They would probable work, but they depend on tension to keep them from slipping. I would prefer a positive drive that doesn't depend on tension.

 

[dsage]

Brian:

Try these guys for timing pulleys and belts. Close to you as well. (well sort of - Janetville).

http://www.steppermotorcanada.ca/index.html


Sage