Driver Casting Repro
Re: Driver Casting Repro
Rub the pattern with graphite.
That made a big difference even with 3D printed patterns.
Karl
That made a big difference even with 3D printed patterns.
Karl
Re: Driver Casting Repro
Gray iron is prone to cracking, very unlike ductile. It is also much lower in tensile strength, depending on the alloys in question. All properties being equal, ductile is stronger. That's due to the fact that the free carbon (graphite) in ductile being tiny spheres instead of flakes. The result of using ductile is that it can be readily welded, it has greater tensile strength and is ****ductile****, very unlike gray iron.
Interestingly, chemically they're almost identical. Gray iron is inoculated in order for ductile to be poured. The one caveat is that the sulfur content must be low, otherwise it interferes with the inoculation process. With modern melting techniques (induction melting instead of cupola melting), it shouldn't be much of an issue to the foundry.
Where ductile really shines is that flanges are not easily broken. Ductile wheels have the potential to withstand a lot more punishment in a derailment. All in all, a better choice. They machine almost identically, although ductile yields chips that tend to hold together, but are readily broken, while gray iron tends to yield crumbles. Both are "dusty" (therefore dirty) to machine.
H
Wise people talk because they have something to say. Fools talk because they have to say something.
Re: Driver Casting Repro
Dave,
I watched your video on the driver pattern a few times before I started prepping everything..and then a few times more when I was mixing the stuff. Top notch as always.
-jlakes85
I watched your video on the driver pattern a few times before I started prepping everything..and then a few times more when I was mixing the stuff. Top notch as always.
-jlakes85
Re: Driver Casting Repro
Are you using Kwick Kast parting wax?
Charlie Pipes
Mid-South Live Steamers
Current Projects:
Scratch Built 3 3/4 scale 0-4-4 Forney
Little Engines American
20 Ton Shay (Castings and Plans Purchased for future)
Mid-South Live Steamers
Current Projects:
Scratch Built 3 3/4 scale 0-4-4 Forney
Little Engines American
20 Ton Shay (Castings and Plans Purchased for future)
Re: Driver Casting Repro
Charlie,
I just had my first quart delivered today..no more screwing with furniture polish..I learned my lesson
I just had my first quart delivered today..no more screwing with furniture polish..I learned my lesson
Re: Driver Casting Repro
Challenge 95 release from BJB Enterprises in Tustin, Ca works as it's supposed to in a Patternshop environment. Must dry completely before any plastic is poured against it. Lacquer sanding sealer is far better than paint as a sealer for the wood or plastic pattern. Proper draft and smoothness of pattern is critical.
Re: Driver Casting Repro
I did some drivers by a different method, I made three Match Plates.
I then used CO2 sand to make the mold, and being hardened it was easy to bring the molds to that iron foundry mentioned below:
http://www.chaski.org/homemachinist/vie ... 7&start=12
I then used CO2 sand to make the mold, and being hardened it was easy to bring the molds to that iron foundry mentioned below:
http://www.chaski.org/homemachinist/vie ... 7&start=12
Re: Driver Casting Repro
Here is the end result. Not too bad I don't think. I'm letting this park on the band saw table overnight to set. Thanks for all of the pointers and suggestions. Next up are the cylinders.
-jlakes85
- Trainman4602
- Posts: 3482
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Re: Driver Casting Repro
What is all the roughness from. It should be smooth as a babys butt
Last edited by Trainman4602 on Sat May 18, 2019 7:23 pm, edited 1 time in total.
ALLWAYS OPERATING MY TRAIN IN A SAFE MANNER USING AUTOMATIC AIR BRAKES
- Trainman4602
- Posts: 3482
- Joined: Sat Oct 16, 2004 9:26 pm
- Location: New Jersey
Re: Driver Casting Repro
This is picture of a mold for the 0-4-0 driver and also the match plate
ALLWAYS OPERATING MY TRAIN IN A SAFE MANNER USING AUTOMATIC AIR BRAKES
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Re: Driver Casting Repro
This is interesting:
http://www.ijirse.com/wp-content/upload ... /1160B.pdf
They are 3D printing the moulds directly with sodium silicate/sand using a process similar to the laser sintering process but with a CO2 jet instead of a laser. No pattern at all.
http://www.ijirse.com/wp-content/upload ... /1160B.pdf
They are 3D printing the moulds directly with sodium silicate/sand using a process similar to the laser sintering process but with a CO2 jet instead of a laser. No pattern at all.
Re: Driver Casting Repro
Hi Dave,
The white stuff is plasticine that was used in a couple of questionable areas. I still have to remove that and give the pattern a once over before mounting
The white stuff is plasticine that was used in a couple of questionable areas. I still have to remove that and give the pattern a once over before mounting