Ball Hopper Monitor - Casting Project

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Needs some work on the draft but wrapped OK

I had trouble getting draft on a logo once (once?!) so I extruded it onto the surface with no draft, 3D printed it and used Milliput epoxy putty to create the fillet required. I shaped the end of a small paint brush to get the fillet shape. It took a while, but it worked. I could only fillet a short section at a time because the putty hardened quickly. I used putty instead of plastic filler because the filler was difficult to sand after hardening, whereas the putty could be smoothed fairly easily.
Needs some work on the draft but wrapped OK

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That is really nice.

I need to figure out how to do that.

There are a couple of approaches to the draft on lettering like that.

The approach I took on the Phoenix casting was to just 3D print it with no draft, and then fill in with wall patch compound, and use a damp rag to wipe some of it out after it started to set up.

Pictures attached.
This was the 1st attempt to make the pattern.

This was attempt #2 at the Phoenix pattern, and I gave it a curved face.

I cast the first one in 356 aluminum, and then cast two more in gray iron.

Turned out pretty well, and that finish is straight out of the mold, which is the benefit of using a ceramic sprayed-on mold coat.

So the same sort of treatment could be used for the Monitor letters.


I guess if you send me a STEP or similar file, I could 3D print it at the correct size.

I think it would be best to cut a rectangle around it, like a backing plate, about 3/16" thick, and I could 3D print the tank pattern with a corresponding rectangular hole in the side, and insert the lettering.

This is my 1st and 2nd attempt at a flywheel 3D model.
The model on the left has flat spokes, and the one on the right has tapered ellipsoidal spokes.

I like the one on the right a lot more, and it is much closer to an original flywheel than the flat spoke design.

Not my photo in the center, and I am not sure where I got that one.

Flywheels are really difficult to get looking like the original.
I think a need slightly more fillet at the ends of the spokes.


The problem seems to be that the outline is made up of several splines and that is causing problems. The dot above the "i" is just a circle which I can add a duel dimemsion chamfer to which gives me draft but it won't run around the edge of the rest of it.

I'll try adding draft to a flat version, may be possible to print it onto a flat backing and then bend that to fit into a curved pocket. That is what I did with the Denny that I posted the screen shot of earlier - CNC cut the letters in soft brass with 30deg draft and then bent that to fit and silver soldered it in.

Nice conversations going on here. A pleasure to watch.

But Pat, no google? You already use youtube. You could use a vpn and incognito mode, or something like that.
No offense intended, and no answer required, LOL, just yanking your chain. ;)

P.S. I have been resisting the facebook urge.
I'm getting somewhere:)

I redid the spline for the swirly M tracing over Pat's original and then wrapped it onto a cylinder in Alibre but wa snot having much luck with draft, chamfers or fillets so exported it as and .STP file and opened in Fusion which allowed me to add a fillet. Just need to do the rest of teh text and also tweak the splines on the M

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Nice conversations going on here. A pleasure to watch.

But Pat, no google? You already use youtube. You could use a vpn and incognito mode, or something like that.
No offense intended, and no answer required, LOL, just yanking your chain. ;)

P.S. I have been resisting the facebook urge.
No I don't use ytube.
I am on Vimeo.

I was on Facebook for 2 days, but they got really really creepy.
I was trying to stay incognito, and they sent me an email, and said that in order for them to continue my account, they needed a close up photo of my face.
I sent the a reply email "fu".
At first I thought it was a spoof emai, but then I researched it, and Facebook really does send out those emails.

For the two days I was on Facebook, they popped up every person I had ever known, worked with, was related to, and people I had known 40 years ago that I had forgotten existed. They are not kidding when they say they know more about you than you do.
And they track everything you say, everything you do, everything you have purchased, etc.
It is a huge data mining organization, and beyond big brother 1984 stuff.
Creepiest thing I have ever experienced in my life.
It can best be described as the quintasential Orwellian nightmare.

Google/Youtube also got real creepy and starting insisting I enter all sorts of personal information.
A big "fu" to them too.

Sorry for the French language.

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Yep, I would say you are there.
As usual you have come through with a superb solution.

I think that would be very usable for a pattern.

Thanks much for working on that.
It is beyond my capabilities for sure.
You have become a stellar 3D user.

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As with the 3D model I am making for the Frisco Standard, the question comes up, "Which horsepower are you going to model".

This has come up with the Ball Hopper Monitor.

According to one post I found by Maury (the Lone Star Ball Hopper Monitor casting guy), the Lone Star BHM was patterned on a 2hp Monitor, and apparently these were produced in a short and long neck variety (I wonder about why the stroke would vary; perhaps designed for different applications that require high torque), and the Pacific BHM was designed after a 4hp Monitor engine.

I don't know enough about the Ball Hopper Monitor line yet to make any sort of comparison.
I have collected a number of BHM photos, and am studying them.

For the Frisco Standard, I basically settled on the style that I had the best and clearest photos of, and the style that looked best to me from a visual standpoint.

Anybody have any Ball Hopper Monitor research data?

I am trying to find information on the Baker Manufacturing Company, which I am told manufactured the VJ and Ball Hopper Monitor engines, among other things such as windmills.

Here is an article I found, which I assume is the same Baker Company.

The company is older than I thought, being founded in 1873.
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So little information I can find about the Ball Hopper Monitor, or any Monitor gas engine at all.

There is a lot more imformation about the VJ Monitor, but almost nothing I can find about the Ball Hopper Monitor.

I need to play with it some more particularly the height of the logo in relation to th ediameter of the tank which is not currently to scale.

That rendered image would not pull from a sand mould as it stands. The problem is that when you wrap and extrude the sides of the letters radiate out from the ctr of the cylinder so at the extream top and bottom of the M you end up not actually needing draft on the inner edges but the outer edges need in excess of 45deg draft. A fillet does not quite solve the problem as there is still some undercutting which woul dmake it hard to pull the pattern.

It may be a case of just wraping the text and doing a basic extrude which will be OK for 3D printing and then any draft/fillet can be added with bondo or similar once printed.

FB does not have a picture of me and no real personal questions asked or if they were I did not answer but still use it.

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You are lucky to escape the FB police.
I must be a suspicious character.

Seems like my wife has an account.
I will enlist her to ferret out some info.

Perhaps another approach would be to extrude it from a plane into the solid body, and then do a circular cut to trim the letters off.
This would give no draft, but would give consistent straight sides to the letters.

The filling with wall patch compound is no problem, and easy to do.

There is a fine line between draft angle and being able to pull letters.
This would be better as an investment casting, but I am not set up to do that.

I think I can get a pretty good looking logo using just bound sand.

You will need to get the proportional height of the letter and tank diameter approximately corrrect.
I think this one was listed on ebay a while ago (not my photo).


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Projecting it straight onto the curve distorts the letters more so the further from the ctr line they are so top and bottom become too thick

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