Building a Power Model Water Pump

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John_S
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Re: Building a Power Model Water Pump

Post by John_S »

I started with a freshly sharpened drill chucked as high up in the chuck as possible. Once I got as deep as I could, I re-chucked the drill to get the remaining depth.

It was cutting nicely, I was clearing chips regularly... My concern is that the passage hole bulged out the inside bore quite a bit before it broke through at the bottom.

Let's just say I wasn't happy when I realized this had happened.
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Fred_V
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Re: Building a Power Model Water Pump

Post by Fred_V »

John_S wrote:I started with a freshly sharpened drill chucked as high up in the chuck as possible. Once I got as deep as I could, I re-chucked the drill to get the remaining depth.

It was cutting nicely, I was clearing chips regularly... My concern is that the passage hole bulged out the inside bore quite a bit before it broke through at the bottom.

Let's just say I wasn't happy when I realized this had happened.
that's not good. That will wear through pretty soon.
Fred V
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kvom
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Re: Building a Power Model Water Pump

Post by kvom »

For a redo, try a center-cutting carbide endmill. Stiffer than a drill. Cit from both ends if you can line it up accurately.
DeMaxx
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Re: Building a Power Model Water Pump

Post by DeMaxx »

Assuming that is some type of brass. Have you tried neutralising the rake angle of your drill? A positive rake on brass tends to make it grab and will lead it off center.

(first post)
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John_S
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Re: Building a Power Model Water Pump

Post by John_S »

DeMaxx wrote:Assuming that is some type of brass. Have you tried neutralising the rake angle of your drill? A positive rake on brass tends to make it grab and will lead it off center.

(first post)
It's bronze and yup, always grind my drills before working on brass or bronze parts.

RichD and I looked over the casting today and he thinks I should be OK with it as is. The piston uses an O-ring, so hopefully there will be no wear on the cylinder wall.
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Bill Shields
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Re: Building a Power Model Water Pump

Post by Bill Shields »

it isn't bronze, it is red brass....learned that from mike V.

deep drilling holes is very difficult.

question - "because i have been there done that"

how do you KNOW that the angle of the drill is EXACTLY PARALLEL to the bore?

you don't have to be off much to get what you got....

sometimes, drilling from both ends and meeting in the middle makes sense.
Too many things going on to bother listing them.
Bill C
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Re: Building a Power Model Water Pump

Post by Bill C »

Bill Shields wrote:i built a drilling box to hold that head

it allows me to mount the head then bolt down on any of the six sides, and drill through the box as a drill jig to put each hole in the location where needed...including set the head up an angle for those holes requiring it. I drilled the center hole and put in a dowel pin + used that for a reference....

drawings
Bill, do you have any photos of the drilling box you describe? As a newbie, I am always looking to learn ways to set up work to prevent errors. Many thanks, Bill C.
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Bill Shields
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Re: Building a Power Model Water Pump

Post by Bill Shields »

let me get something sorted out and posted

just got home from a trip to Europe where my computer was stolen from the hotel.

i have total backups of everything, but will take a day to get running and to a point where it can be shared.
Too many things going on to bother listing them.
Bill C
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Re: Building a Power Model Water Pump

Post by Bill C »

Bill, thanks! Sorry to hear about your computer being stolen. I am in no hurry, will look forward to learning more about the drilling box when you have time...

Best regards,

Bill C.
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John_S
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Re: Building a Power Model Water Pump

Post by John_S »

Had to give the valve head casting one more good bath in alum to get the last of the broken tap out. There was a tiny little piece left in the very bottom of the hole. I made an extra strong solution this time and put it in the crock pot again. Four hours later and there's not a trace of the tap left! In fact, the solution was so strong when I put the paper clip down into it to clear out the hole with the broken tap it immediately started reacting and bubbled like crazy!


Continuing on with the hopes that the steam cylinder will be OK without any modifications...

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Starting on the water cylinder, facing the top, bottom, and back.

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Finished up this evening by drilling and tapping the four 10-32 holes for the "air inlets." (cosmetic only) You can see a small void in the back face. Just a little tiny one... hopefully that's the only void I come across.

Image
All the parts so far.

Tomorrow night I'll be boring the water cylinder and get a start on the passages in it.
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John_S
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Re: Building a Power Model Water Pump

Post by John_S »

Short night in the shop tonight, so all I got done was boring out the water cylinder:

Image
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John_S
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Re: Building a Power Model Water Pump

Post by John_S »

Picked up a sinus infection so the only machining I've done in the last couple days has been in my dreams while I slept it off!

Got quite a bit done on the water cylinder today though, starting with the top end. Drilled out the valves, water passage, and bolt hole pattern to attach to the spacer:
Image

Finishing up the top end with a notch from the cylinder bore to the water passage:
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Closeup of the top end:
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Bottom end after drilling the other water passage, bolt holes, and notching to the bore:
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Setting up to drill the top end water cross passage. It's a 27deg angle that I marked out on the part itself and aligned to the vice jaw. You can just barely make out the light scribe mark on the front:
Image

Used a 3/16 centercutting endmill to create a flat:
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Then center drilled and drilled out, connecting the valve chamber and the water passage:
Image

Tapped 10-32 for a set-screw plug that will seal up the passage:
Image

Cleaned up a bit and with one of the set screws installed:
Image

That's all for today.
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