NZT School Bus and Caterpillar kits en route to dealers

[jimmo]

What are you casting Pete? Doesn't sound like anything N-scale unless it's something that floats.

[peteski]

Pete casts large sea-going ships (in N scale).

David, thanks for sharing your casting techniques with the forum!  I have a pressure pot but I haven't yet graduated to using it (I'm still playing with simple open-mold castings).  It makes sense that you use slow-setting resin (I couldn't see myself being able to pour a 5-minute resin in bunch of molds, placing it in a pot and pressurizing it, all withing about 2 minutes!  You just confirmed the need to use a slower setting resin.

One thing that bothers me, especially when you use such a high pressure:  when the resin hardens, it contains bunch of tiny air bubbles containing pressurized air.  What happens over time? Won't the constant high pressure in the bubble eventually distort the resin (or pop)? Especially if the bubble is in a thin cross section of the resin or in something like the gear shift lever in your Cat model?   Wouldn't vacuuming the resin instead be safer in the long run?

[DKS]

One thing that bothers me, especially when you use such a high pressure:  when the resin hardens, it contains bunch of tiny air bubbles containing pressurized air.  What happens over time? Won't the constant high pressure in the bubble eventually distort the resin (or pop)? Especially if the bubble is in a thin cross section of the resin or in something like the gear shift lever in your Cat model?   Wouldn't vacuuming the resin instead be safer in the long run?

I have parts I've cast under high pressure that are years old, now. They shown no signs of warping. As it is, all of the (remaining) bubbles are reduced to microscopic size. I can coinfirm this having cast in clear resin, which permits a good look inside:



After having produced many hundreds of parts in a myriad of shapes and sizes, I have yet to be convinced that vacuum degassing is of any real benefit when casting under high pressure.

[peteski]

I have parts I've cast under high pressure that are years old, now. They shown no signs of warping. As it is, all of the (remaining) bubbles are reduced to microscopic size. I can coinfirm this having cast in clear resin, which permits a good look inside:

I guess that I'll be able to see that for myself as soon as I receive my clear buses next week (they have been shipped from MBK today).

[Mark5]

Saw the buses in the store the other day. These are an exceptional value and the decals are a nice touch!

[pnolan48]

One thing that bothers me, especially when you use such a high pressure:  when the resin hardens, it contains bunch of tiny air bubbles containing pressurized air.  What happens over time? Won't the constant high pressure in the bubble eventually distort the resin (or pop)? Especially if the bubble is in a thin cross section of the resin or in something like the gear shift lever in your Cat model?   Wouldn't vacuuming the resin instead be safer in the long run?

Pete,

I think, once the resin sets, the polymer structure would be far stronger than anything compressed gas could affect.

[chicken45]

Athearn makes the casting.  This one has been modified with body-mounts, end sills and grab irons.  The deco is custom and the deck is a laser-cut addition.

Looks great!

[johnh35]

Very nice! Now if we could get a 60's Greyhound bus of that quality...

[Chris333]

Saw the buses in the store the other day. These are an exceptional value and the decals are a nice touch!

Tom Mann head decals?

[Chris333]

So my dozers came in the mail today and    I haven't even opened the package yet and all I see is detail everywhere. I almost want to keep one sealed like a collectible.

You need to get a list of oddball N scale freight cars and start casting!

[up1950s]

You did a small bulldozer , How about a small Payloader . Hough invented them and was the first to use the term Payloader , bought out by IH in 1952 but the Payloader name and the basic design continued . They had rounded corners at the engine end . The HAH model was common to see in the streets around here in the 50's .

http://www.manuals.us/images/products/detail/IMG_0001.117.jpg
http://aweb.s3.amazonaws.com/a25000/b26445.jpg
http://www.heavyequipmentforums.com/attachment.php?attachmentid=9566&stc=1&d=1195584189

[DKS]

I almost want to keep one sealed like a collectible.

Now, that is a compliment! thank you!

You need to get a list of oddball N scale freight cars and start casting!

Can't make any promises, but it wouldn't hurt to start a list...

[Alaska Railroader]

Thanks to David's incredibly fast "cooking" I now have a pile of crawlers and a pile of buses on the dining room table. So much yellow it looks like dandelions are early this year! All the back orders will be shipped ASAP. If you want to order some, now is a very good time to do it. Chris, you can get another one to be your official museum piece! I do have a limited number of red crawlers available.

Karin
Stonebridge Models

[Chris333]

You forgot this 
http://stonebridgemodels.com/

[daniel_leavitt2000]

They come in red too?