The "ORIENTAL"

If you get your sodium silicate percentage right, and gas for 5 seconds only, SS cores are every bit as good as cores made from synthetic materials, with a similar shelf life.
The good thing about SS cores is the low toxicity.
And another advantage of SS cores is that it is very fast to make them; there is no waiting on set or strip time.

I would like to learn the art of linseed oil cores.
They did incredible things with those cores in the day.
.

Edit:
One advantage to resin-bound cores is that the hardener is mixed throughout the core material, and so for a complex core, you don't have to try and gas every area of the core.
It should be noted that there is a catalyst material that can be used with sodium silicate cores, that works like a hardener, and that catalyst eliminates the need for CO2, and allows every complex SS cores to set completely just as if it were a resin core.
Sodium silicate catalyst can be obtained at pottery supply houses.

.
Edit02:
I flame resin-bound cores lightly with a propane flame, to drive off moisture, and burn off any slight amount of uncured resin.
I think you can do the same for sodium silicate cores, ie: lightly flame them; I can't recall if I did that or not.
I do recall baking some sodium silicate cores to be sure they were completely dry.
I try to vent all cores out the top of the mold if possible.

Doing the cores in halves is done as it is faster as you just dump the airset on top and strike it off ( hence pins removed)rather than trying to completely fill the cavity in a closed box. Also easier to get the core out of an open mould so less failure rate.

As these are commercial foundries time = money

So its should be easy to see why the most economic method is used.

The home foundry guy can spend as long as they like filling cores, backing, etc and if the first one fails then they just make another and all it has cost is a bit of their time.

I was looking through the foundry photos that I have collected over the years, and there is someone from Australia who cast an engine for a scale tractor, and he cast the passages in the head.
Some of his passage cores extended out round into the coreprint area, and others had a square end on the coreprint to hold it at an exact angle.

Cretors used a square end on some of their cores, such as for a slanted bearing housing, to get the babbitt recess in the exact orientation.
Sometimes a round on one end of the coreprint, and a square on the opposite end coreprint.

Thinking about your two-piece corebox, I recalled some cores I made, and I used a two piece corebox that did not have a top or bottom.
You just clamp the two pieces to the table, ram with sodium silicate sand, gas, and then release the clamps.

If you need a convex or concave surface on the top or bottom of the core, you can have an insert that goes in at the bottom, and have strike off surfaces on top that are convex or concave.

Here are a few pictures of my two-piece corebox.

.

Using a corebox that does not have a top or bottom would save you from having to make two core pieces and cement them together.

.

Hi  Maury, Thank you for inviting me to visit your build log.  I had only asked for a few pictures but this is far beyond my expectations. 

As previously mentioned by Dave Otto, Jack Anderson once told me he enjoyed writing about engines and their history more than he enjoyed working on engines.  I completely understand that as I prefer to build engines rather than comment in a forum.  I occasionally read some builds and marvel at the skill & ingenuity of the builders especially when they have few tools.

Special credit should go to Bill Prine for restoring the ORIENTAL.  It may be the only one that size and the work Bill did is remarkable.  As Dave mentioned, it spent most of its life on a lake bottom, a few years out in the weather and then years in Bill's shop. 

When I went to see the ORIENTAL, in the last century before some of you were born, it was a sad sight.  Bill had a 5 gallon bucket of mud with many broken iron pieces in it.   That was one of the cylinder heads.  I spent a couple enjoyable days in a sunny driveway putting a 3D puzzle together and getting critical measurements.  My intention was to measure & sketch enough I could build a model. 

Then life and other engines got in the way and I am overjoyed Maury is going to take this project over and share it with all of us.  Please let me know if I can be of any help.

Roland

For those who understand, no explanation is needed.
For those who do not understand, no explanation is possible.

I've been prepping all the parts for the Oriental patterns. The 3D models get extra material for machining,
then that are scaled 1.015x. Parts that need to be split are then divided. Next draft is added, and the fillets
are added. Sometimes a also add the gating to the pattern for convenience for making the pattern board.

At this point, I have all the parts for castings are prepped and printed, except for the base, crank case,
and flywheel. They are too big for my printer or CNC machine, so I'm going to have to buy a larger printer.
Anybody have any experience with the QIDI Plus 4 3D printer?

I am starting to mount these on boards for the big pour day. So far I have the head and valve parts.
These parts are made in both a left hand and right hand version.

Is it not possible to print the larger patterns in two or more pieces and then join them together, should be stronger as you are mounting them onto boards. I have seen it done where the joints are modified to have interlocking dovetails of shaped like jigsaw puzzel pieces

Alternatively for the flywheel cut it in two halves or smaller segments. I had to do this 9" one in two different halves due to the 5 spoke pattern but it was just a case of rotating the blank 180deg and running a second cut. Or you could turn the rim on your lathe and assemble printed spokes onto the board again much like this where I machined the rim and added the CNC cut spokes

I purchased a Prusa XL, which as a 14 inch cubed print area.
It has been stable so far, and the bed adhesion has been outstanding, which is critical as you get into a very wide print.
And does not have a problem operating without an enclosure, even with a window air conditioning unit blowing a cold draft across while printing (printing PLA).
Completely automatic build plate leveling.
Perfect first layer build every time without any manual adjustment.
The large footprint saves time by avoiding piecing patterns together.
And multiple patterns can be printed at the same time, given how much real estate is on the bed.

I am not familiar with the QIDI Plus 4.
Price looks to be very reasonable, assuming it works well.

Edit:
A review from 2024:

https://3dprint.com/313877/qidi-plus-4-3d-printer-review-hotter-than-the-competition-is-it-safe/
.

Jason, thanks for the response. Yes, I have tried to print patterns in parts before, actually several times. I have never been totally happy with the results. I think it's ok for core boxes though. The crank case pattern I'm doing has lettering, and would have to be split on the lettering. Probably a bad idea.

CI, I have looked at the Prusa, Ultimate pattern maker, but a bit pricey. I actually prefer the QIDI Max4 , same size as the Prusa, but it's on PreOrder at this time. They will need a year to get the bugs worked out.  I got stung really bad buying the Ender 5 S1 on PreOrder, and am really gun shy about doing that again. The S1 never did work, even after weeks of going round and round with Creality customer service. Now it is just a brand new $500 piece of junk sitting in my shop. Obviously, I will NEVER buy another Creality product!!!!
The reviews on the Plus 4 are good, and it's on the 4th revision, should be a reliable printer. Price is good, and the build volume ai just enough to do my large parts.

Basically one pays for support with Prusa up front.
I thought I had a problem with my MK3, but it turned out to be something I was doing wrong.
Prusa offered to take the machine back, no questions asked, with a full refund.
Luckily I figured it out, and the machine has worked well since, except for being picky about bed lifting.
The XL does not seem to bed lift no matter what, and so that is a really good feature.
Also, if the power goes out, the XL print picks up where it left off when the power returns.
But yes, pricey.

.

Continuing with mounting the patterns.All total, I will have 5 patterns, which is all I have sand for. Hopefully after another week of PT on my back I'll be able to do a pour. We'll see.

Ok, I've been a little slow about posting.
After receiving the Plus 4 and getting it going, I took it out for a spin. A Really Nice Printer!
I have the flywheel, Piston, liner and core boxes. These parts go tot the iron foundry, and may take a while to get the castings back.
In the mean time, I will (I hope) be casting the previously shown patterns in aluminum in my home foundry.

Very nice work !
.

After a couple of bad starts with some bad filament and first layer issues, I have made progress on the crank case. The core box is in 3 pieces, as there is an overhang with the main bearing bosses. This is about 17 hours worth of printing. The crank case drag pattern took about 18 hours. I learned about filament tangles doing this exercise. If you use part of a roll and remove it from your machine for later use, be very careful to keep the winds tight while doing so, or it will backlash and cause problems.

I forsee a large avalanch of castings coming my way soon, for this project and three uncompleted ones.