Casting kit business?

[GreenTwin]

I use LinoCure (tm), which is a 3-part binder system, with a resin, a hardener, and a catalyst.
One does have to wear a commercial-grade chemical-rated respirator, and nitrile gloves when handling this product.
The catalyst is nice since it allows one to vary the set time.

There is a set time, and a strip time.
One wants to remove the patterns prior to the end of the strip time, else they will be permanently glued to the mold.

I have seen some use epoxy as a binder, but I am not sure about how to do that.

I also use sodium silicate, and I have some that uses a hardener, and a catalyst.
Sodium silicate does not have the harsh chemical properties that the resin binder has.

Bound sand must be very dry, and I use a commercial product called OK85 (from Oklahoma), and I think it is oven-dried.

I use a ceramic mold coat (same as in the slingshot video above), and that really helps with the surface finish.

As far as covering the lines in 3D printed parts, my plan is to use a thin layer of n auto body skim coat, and then sand most of that off.
Perhaps a product like this:
https://crestauto.com/shop/body-filler-finishing-glaze-supplies/finishing-glaze/skim-coat/
Below are some molds, and some castings.

 

[GreenTwin]

A few more pictures.

 

[GreenTwin]

Pictures

 

[GreenTwin]

Pictures.

 

[GreenTwin]

more

 

[GreenTwin]

continued

 

[GreenTwin]

Here is an example of what the ceramic mold coat will do for surface finish.
The casting came out of the sand almost clean, and cleanup consisted of brushing off the remaining sand with a dry paintbrush.

I don't know of anyone that pulls bright shiny gray iron castings directly out of a sand mold.
Ceramic mold coat basically eliminates post-casting cleanup, wire brushing, etc.

This was the "Phoenix" pour, which was a celebration of COVID not taking us out, and so we rise once again to make iron castings.

 

[GreenTwin]

I started learning how to cast with 356 aluminum, then cast a few iron parts, but I did not really have iron figured out completely, so I went back to aluminum for a while, and then finally figured out exactly how to cast gray iron consistently.
Now days I cast iron exclusively except when I make permanent patterns in 356 aluminum.

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[GreenTwin]

I hacked out a phoenix design in Autocad, and then made a 3D print.
Started out as a belt buckle, but then became more like a plaque or something due to the size.

I printed the 3D pattern with a curved front surface, and then filled it with wall patching compound.
Before the water-based wall patching compound fully sets, you wipe it to a fillet with a damp cloth.

This was fun stuff for sure.
I did not quite get all the lines filled, but I don't have an skim coat material yet either.

 

[GreenTwin]

My iron furnace used a diesel burner with a spray nozzle, similar to a paint sprayer, but installed in the end of a burner tube.

My combustion air blower is a Toro variable speed leaf blower.

Pouring your own iron parts is just a blast.
I am not sure how else to describe it.
I wish more folks would get into the iron casting hobby.

There is no doubt I could start a casting kit company.
I can design from photos, and basically make everything that is needed for an engine.
I can make commercial-grade gray iron castings all day long, but its just a hobby at this point.

 

[GreenTwin]

You can see how accurately the resin bound sand picks up surface defects.
The outline of the blue painter's tape was completely copied in this iron casting.
This was a freebee I did, just to see if I could remake a broken bearing cap, and so I did not spend much time finishing out the pattern.

 

[ajoeiam]

A very impressive collection of great products.

good on you sir!!!!!!!!!!

 

[GreenTwin]

A very impressive collection of great products.

good on you sir!!!!!!!!!!

Thanks much.
I love this hobby !

I forgot to answer the question asked, which was "Is resin-bound sand reuable?".
Not easily; you have to burn off the resin.
Commercial foundries do reuse resin-bound sand, but there is a process involved in doing that.

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[Jasonb]

Back on topic I see they are now relisted at $23K, few more months and they may come down to something realistic

 

[GreenTwin]

And as a comparision, all of the my foundry equipment and all of my castings seen above were made and constructed for a fraction of $23k.

Best of luck to the seller, but it seems $23k is just out in left field.
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[William May]

No-one has pointed out that with just a little forward planning, a 3D printer can be left running overnight...

-Andrew UK

You need MORE than forward planning. I volunteer at a local makerspace, and nearly every time I go in, there is someone's failed print project laying in a heap on one of the 3D printers they have. There are now 3 printers, and this happens with all of them.

 

[Oldiron]

This dam covid is kicking my butt. Glad I started this conversation. What I'm getting here is the patterns may be usable or may need modification before the foundry, if you can find one, can use them. The plans are what they are, usable I'm sure. Rights, well these are nothing but models of old engines. If you want to start from scratch nothing is stopping you. The historical aspect of these is neat but how much money is that worth? This sounds like the manual vs CNC argument, you can use either to make money but where is the future from a business perspective? The sticking point is these already exist. Sure someone could redo them with modern methods and probably turn out kits more efficiently but I don't see a line of people rushing out to do it. As said in the beginning, finding a foundry is iffy and the price for the patterns etc. is the question. Seems like the price would have to be low enough for you to become a pattern collector if the foundry and cost of material doesn't add up. Bob

 

[GreenTwin]

And as a comparision, all of the my foundry equipment and all of my castings seen above were made and constructed for a fraction of $23k.

Best of luck to the seller, but it seems $23k is just out in left field.
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I built a first-rate furnace too, with the top of the line commercial materials.
It may look a bit rough on the outside, it it is designed to basically last indefinitely at iron temperatures.
The shell is all stainless constrution (a few beer kegs bit the dust on this furnace), so never any corrosion problems, even if you leave it outdoors.
Stainless burner tube.
I probably have less than a grand in my furnace, and I spared no expense on quality of materials.

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[Jasonb]

Bob, I think a lot of the kits that are/were available came about because someone wanted to make a model of a specific engine so they made patterns and had castings made. They then found that others were interested in the castings so ran a few more sets off which required no more investment as they had the patterns and just treated it as a bit of Pocket money to finance their hobby including making more engines for themselves and then others.

I've done a bit of pattern making in association with Graham Corry of Alyn foundry and we have just run off two sets of castings which is one each, he gets some CNC machined patterns and I get some castings in return. If a few others want castings in the future then they may be cast to order but there is no real investment as graham already has the patterns and a couple of capable and willing foundrys to do the casting..

What makes this situation different is a considerable sum is being asked for the patterns and with the current economic and foundry issues I can't see a way of ever getting that sort of money back

 

[Steamchick]

WOW! Luke - again I am impressed with what you do.
Green Twin: You get a WOW! too, as you look to be in the same semi-professional league and have mastered your process.
I know Luke sells stuff, but not sure he makes a real profit, or just covers costs... but he should be the best advisor I have come across to advise on how to progress from "Hobby" to "business" - as you have the technology, but need to be sure the market can be developed. I.E. You need to know "What product will sell profitably?" - That needs enough customers - longer term - and enough "Market value per item"... In the UK Stuart Models (iron castings of many old engines) are possible the best example of a long-term brand name that I think has had a few owners try and make a business of the product line. Stuart Models | Steam Engines | Model Engineering | Executive Toys
Thankyou both for doing your stuff and telling us about it.
K2.