Author Topic: Steam Tractor 3/4" (Rudy K)  (Read 242126 times)

Offline steamboatmodel

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Re: Steam Tractor 3/4" (Rudy K)
« Reply #1005 on: May 08, 2018, 01:15:55 AM »
When you seated the ball did you remove that ball and use a new one in the valve?
Gerald.
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Offline crueby

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Re: Steam Tractor 3/4" (Rudy K)
« Reply #1006 on: May 08, 2018, 02:11:50 AM »
Nice job on the pump!  Where did you get the stainless wire for the springs?

Online Kim

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Re: Steam Tractor 3/4" (Rudy K)
« Reply #1007 on: May 08, 2018, 06:12:02 AM »
When you seated the ball did you remove that ball and use a new one in the valve?
Gerald.

Interesting question... I considered it, and I kinda thought I would.  But I looked at the bearing after I had used it for the seat and didn't see any mark on it at all.  The brass is fairly soft in comparison to a stainless steel bearing I'd guess. I think the bearings are hardened too (though I'm not sure why I think that.  I believe I read it somewhere, but now I'm not sure.)

So, in the end, I didn't swap it out. I used the same ball as was used for the whacking. 

I'd be open for other people's opinion on this.  Should I swap out the bearings for un-whacked ones?  Would that be better?  Do others do this?
Kim

Online Kim

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Re: Steam Tractor 3/4" (Rudy K)
« Reply #1008 on: May 08, 2018, 06:39:14 AM »
Nice job on the pump!  Where did you get the stainless wire for the springs?

Hi Chris,
I ordered this off Amazon.  It's stainless steel beading wire.  I'm not certain that it is 'cold drawn' stainless steel.  But it seems to be working OK.  You can stretch the spring out of shape fairly easily, but I'd expect that would be the case for any spring made of 0.012" wire. (this is 28GA which is actually 0.013"). https://www.amazon.com/gp/product/B0063DH7KE/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1

If it is annealed, there should be someway to harden it?  Like heating & quenching?  Does that work for stainless?  Or does hardening it make it too brittle?  I just used it as is, but I don't know if it will have the lasting quality for a sprint.

Kim

Offline Bluechip

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Re: Steam Tractor 3/4" (Rudy K)
« Reply #1009 on: May 08, 2018, 09:38:19 AM »
The label says 304 SS and it's possible to buy 304 commercial springs so I would think they can be heat treated ???

www.ebay.co.uk/itm/10pcs-304-Stainless-Steel-Spring-Compression-Pressure-Small-Springs-0-3mm-0-5mm-/263132348208

Dave

Offline crueby

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Re: Steam Tractor 3/4" (Rudy K)
« Reply #1010 on: May 08, 2018, 02:02:05 PM »
When you seated the ball did you remove that ball and use a new one in the valve?
Gerald.

Interesting question... I considered it, and I kinda thought I would.  But I looked at the bearing after I had used it for the seat and didn't see any mark on it at all.  The brass is fairly soft in comparison to a stainless steel bearing I'd guess. I think the bearings are hardened too (though I'm not sure why I think that.  I believe I read it somewhere, but now I'm not sure.)

So, in the end, I didn't swap it out. I used the same ball as was used for the whacking. 

I'd be open for other people's opinion on this.  Should I swap out the bearings for un-whacked ones?  Would that be better?  Do others do this?
Kim
Kozo suggests using a new one in case the bearing got deformed, especially if you used a steel rod to seat it.

Offline crueby

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Re: Steam Tractor 3/4" (Rudy K)
« Reply #1011 on: May 08, 2018, 02:08:02 PM »
The label says 304 SS and it's possible to buy 304 commercial springs so I would think they can be heat treated ???

www.ebay.co.uk/itm/10pcs-304-Stainless-Steel-Spring-Compression-Pressure-Small-Springs-0-3mm-0-5mm-/263132348208

Dave
300 series stainless doesnt harden by heat/quench, just by work hardening, from what I have read. If you stretch it before winding it will be better as a spring. Hold end in a vise, unroll what you need, stretch by holding other end in pliers and pull, you'll feel it stretch a bit and it will straighten and get stiffer. Then wind it.

Online Kim

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Re: Steam Tractor 3/4" (Rudy K)
« Reply #1012 on: May 08, 2018, 04:56:47 PM »
Thanks for the follow-up Dave and Chris.

300 series stainless doesnt harden by heat/quench, just by work hardening, from what I have read. If you stretch it before winding it will be better as a spring. Hold end in a vise, unroll what you need, stretch by holding other end in pliers and pull, you'll feel it stretch a bit and it will straighten and get stiffer. Then wind it.

This is great info!  I'll have to try that and see how it works out.
Kim

Online Kim

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Re: Steam Tractor 3/4" (Rudy K)
« Reply #1013 on: May 08, 2018, 04:58:50 PM »
When you seated the ball did you remove that ball and use a new one in the valve?
Gerald.

Interesting question... I considered it, and I kinda thought I would.  But I looked at the bearing after I had used it for the seat and didn't see any mark on it at all.  The brass is fairly soft in comparison to a stainless steel bearing I'd guess. I think the bearings are hardened too (though I'm not sure why I think that.  I believe I read it somewhere, but now I'm not sure.)

So, in the end, I didn't swap it out. I used the same ball as was used for the whacking. 

I'd be open for other people's opinion on this.  Should I swap out the bearings for un-whacked ones?  Would that be better?  Do others do this?
Kim
Kozo suggests using a new one in case the bearing got deformed, especially if you used a steel rod to seat it.

Interesting.  Maybe that's why I was thinking about it in the first place (because I've read Kozo's book :) ).  It certainly works, but when under pressure, it may not seat as well if its out of round.   I did, however, use a brass punch to seat the bearing, so maybe its not too bad?

Thanks,
Kim

Online Kim

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Re: Steam Tractor 3/4" (Rudy K)
« Reply #1014 on: May 09, 2018, 03:53:44 AM »
The final part of the pump will be the handle.

I made that from a 3/8” rod.  I made it from steel, cause that’s what I had handy.  I realize that stainless would be a better choice for something that’s going to see a lot of water, but such is life.  I guess if it starts rusting out I can always make another one  :embarassed:

I rounded off one end of the rod then put a hole in the other end for the primary pivot.


Then 90 degrees from that, I drilled a 1/8” hole as a termination for the 1/8” slit (that we’ll cut in the next step).


Back to the original orientation, then using a slitting saw, I cut along the top of the slit:


Then along the bottom.  I got a nice little sliver of steel out of it too. This method worked pretty well.


And of course, I realized I hadn’t drilled the hole for the plunger linkage.  So I had to go back and do that.  Since I’d already made the slit, I used a 1/8” scrap of aluminum and a little machinists jack to prop it up.


Now for the link.  This is a piece of 1/8”x3/8” steel.  Drill the two pivot holes.


Then cut it off and round the ends on the belt sander.
Here’s the pump handle pieces:


And here it is all assembled.


And the victory video to prove that it really does work!
<a href="https://www.youtube.com/watch?v=5As2cn3J6Ys" target="_blank">http://www.youtube.com/watch?v=5As2cn3J6Ys</a>

Next, I’ll be hooking up the pressure gauge to make sure it will provide the pressure I need.

Kim

Online Kim

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Re: Steam Tractor 3/4" (Rudy K)
« Reply #1015 on: May 09, 2018, 08:59:55 PM »
Well, I hooked up the pressure gauge directly to the pump, and sure enough, I can get a pretty good pressure (over 60 lbs – that’s all I need for this test) but it leaks away very quickly, like in 5-10 seconds.

I played around with all the connections and joints and am sure that nothing is leaking there.  So, I’m forced to believe that the outlet ball isn’t seating well.  In fact, eventually I noticed that I could vary the pressure up and down by moving the plunger in and out.  The plunger should only make the pressure go up, not down.  This further led me to believe that the outlet ball isn’t seating well at all.

I tried giving the bearing another good whack, to seat it better.  And I replaced the bearing with a new one, so that I’d know it was round.  But still, same issue.

It was hard to see down in the hole to see the seat, but it doesn’t look like a nice clean circle/seat like I have on the inlet bearing.

Here are my two plans:

1)   Re-drill the outlet seat – more carefully this time (I see that Kozo recommends using a D-bit, to get a nice smooth surface on the bottom of the hole.  I just used a #3 drill bit.  Maybe that didn’t make a clean enough edge to seat well.

2)   Get a check valve to go on the output side of the pump.  It’ll get up to pressure, it just won’t hold it.

I started with #1, made a D-bit, then as I was heat treating it, a humming bird flew into my shop and seemed to get stuck.  It couldn’t figure out how to get out.  So, I dropped the red-hot D-bit into the water and went to help the humming bird.

With the humming bird safely out in the wild again, I pulled the D-bit out to see that I’d melted the tip of it.  It wasn’t a D-bit anymore :(.  It was more of a blob bit.  Ah well.  Have to be more careful next time.  But not today.  That’s enough for today.

I’m blaming it on the Humming bird!
Kim

Offline crueby

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Re: Steam Tractor 3/4" (Rudy K)
« Reply #1016 on: May 09, 2018, 09:47:19 PM »
A humming bird. Yeah right. And a dog ate my homework!   :lolb:

Thats got to be the wildest event I've read about in a while!

Hope the next D-bit works better. I had a small boring head bit that I was able to use on mine - got a nice flat bottom hole that way, essentially the same as a d bit.

Offline Dave Otto

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Re: Steam Tractor 3/4" (Rudy K)
« Reply #1017 on: May 10, 2018, 01:13:50 AM »
Hey Kim

Nice work on the pump! That twist drill probably didn't leave the best surface for a valve seat, I'm sure that you will have better luck with the D-bit; especially if you let it dwell at the bottom while coming up against the depth stop on the quill of your mill.
Another thing to think about is that brass is pretty hard and maybe you aren't smacking the ball hard enough. :lolb:
Maybe annealing the brass valve seats would soften them enough so the ball could make it's mark? Just thinking out loud here. I have no experience in this area.
Something else that you could try would be to silver solder one of the balls to a rod and use it as a lap with some compound to lap the seat in. At least you would be able to see your progress. :)

It's good to see that casting finally be turned into a usable part.


Dave

Offline b.lindsey

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Re: Steam Tractor 3/4" (Rudy K)
« Reply #1018 on: May 10, 2018, 01:24:43 AM »
Its looking good and pumping well Kim. I think once you sort out the seal issues it should hold pressure. The above suggestions all seem reasonable as well.

Bill

Online Kim

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Re: Steam Tractor 3/4" (Rudy K)
« Reply #1019 on: May 10, 2018, 05:40:28 AM »
Thanks Chris, Dave, and Bill,
Appreciate the thoughts on this.  This IS my first rodeo here, and I'm happy to take all the input people have to offer  O:-)

I'll have to add the lapping as another alternative to my list.  But thinking about it more, the twist drill left a "V" shaped bottom, and probably not a very smooth one at that.  The other bearing seat I made was a clean 90 degree edge on the inlet side, and it made a very solid seat using the "Whack" method.  That one is holding the pressure - It shouldn't have to, but its doing it.  Right now, the only leak I have is between the plunger and the O-ring (guess I didn't get that in there right enough.  But it works well enough to get the water up to pressure, if only the outlet bearing was seating well.

So, next time, its off to try a D-bit.

And no humming birds allowed! :)
Kim

 

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