Brass KMT Centipede Re-powering

[glakedylan]

what a super piece of work
creatively addressed
skillfully completed
wow! great thread with wonderful write up and photos
very appreciated

sincerely--

[u18b]

Been making a little bit of progress.

Either too much work or too much rain has held me up.

But I finally sandblasted and primed the parts.




And just finished the green paint.

[u18b]

Got a lot of progress done on this today.

Green paint with clear coat.
Assembled.
Added operating headlight.
Added window glass.
Added extra weight.

Dang.   This thing weighs in at over 200 grams- that is approaching half a pound!

[delamaize]

Damn, that thing is going to be a stump puller.

[daniel_leavitt2000]

Ron, I have been watching this thread from afar... I need to start work on my Hallmark Dash 8.
One thing that has me worried about this build is the low-temp alloy and/or resin worm box. This area always generates a bit of heat after prolonged running. How are you going to keep this area from heating up enough to melt the alloy?

If I recall, Walthers has three temperature alloys. Maybe the 350-400* one would better suit this part?

[Chris333]

Walther's lo-temp is just Cerrobend, http://en.wikipedia.org/wiki/Wood%27s_metal

I bought a big piece on e-bay a while back. It was listed as being used to fill pipes with before bending them, like you would use sand.

[u18b]

Daniel,
I'm thinking you are correct.

Earlier in this thread, I made some gearboxes with Walther's Temp-lo.
As Chris said, it has a fairly low melting point.

I also made some boxes out of Alumilite.
This stuff is great overall, but when heated it actually become bendable.

But in the new EP-2 thread, I talked about casting metal on page 2.
https://www.therailwire.net/forum/index.php?topic=36215.15


I also have made some boxes out of higher temp alloy.
Tru-281 melts at almost 300 degrees.
That should be tough enough I would think.  Heck, if this loco gets THAT hot, then the solder joints might start melting.
The only difference is that I will need some insulated 0-80 screws since the gearboxes would be charged.

[nickelplate759]

Amazing work!

What do you use for primer on brass?

George

[daniel_leavitt2000]

Daniel,
I'm thinking you are correct.

Earlier in this thread, I made some gearboxes with Walther's Temp-lo.
As Chris said, it has a fairly low melting point.

I also made some boxes out of Alumilite.
This stuff is great overall, but when heated it actually become bendable.

But in the new EP-2 thread, I talked about casting metal on page 2.
https://www.therailwire.net/forum/index.php?topic=36215.15


I also have made some boxes out of higher temp alloy.
Tru-281 melts at almost 300 degrees.
That should be tough enough I would think.  Heck, if this loco gets THAT hot, then the solder joints might start melting.
The only difference is that I will need some insulated 0-80 screws since the gearboxes would be charged.

There is two types of heat. Overall heat... think a car engine heating up, and localized heat, like the cylinder jackets and piston heads. If anything goes out of whack in that worm bearing, it could very well heat to over 300* across a very small area.

[peteski]

There is two types of heat. Overall heat... think a car engine heating up, and localized heat, like the cylinder jackets and piston heads. If anything goes out of whack in that worm bearing, it could very well heat to over 300* across a very small area.

Geez Daniel, are you taking a 1:1 locomotive or N scale model? 
Even localized, I think that if some piece of your 1:160 model's gear-train got up to 300 degrees F the model would be in a serious trouble at that point (brass or plastic)!  If the parts are too hot to touch with a bare hand they might be as low as 120-160 degrees F.

[u18b]

Amazing work!

What do you use for primer on brass?

George

Hi George,

I use a Pasche air eraser to "sandblast" the brass with 220 grit aluminum oxide.
I wash with acetone and dry.
Then airbrush old Floquil Zinc Chromate Primer.  It really adheres to the brass.
 

[u18b]

Daniel, you raise a good point and might be correct.

But I could not ever see one of my locos hitting 300 degrees (that temp is instant burn if it touches your finger, not merely an ouch).

I keep my bearings oiled and if they EVER squeal I stop the loco immediately and fix it.

I would also think.... that before that level of SERIOUS friction happened, you would see a degradation of performance.
Hopefully no one would run a loco that was getting slower, and slower, and s l o w e r.
Man you'd be asking for trouble if you did that.

I'm thinking I'll be safe at 300 degree alloy.

[u18b]

Dang.

Whoever said PRR decals were easy???




Making very slow progress.

[victor miranda]

Hi U18b,

what I heard was that the 'Paint' was easy.

them stripes never came out right for me.
I tried several times on an f-something, long ago.

I settled on uneven from one side to the other.
.... the decals flaked off after awhile.

I have no idea where that thing ended up.

victor

[u18b]

Yep.  The stripes are not easy.

The problem is the decals are VERY thin and delicate.

So while lining up 5 lines is actually easy, the problem happens with the setting solution.
The setting solution itself can deform the 5 lines.

Also.... who wants to add P E N N S Y V A N I A  one blooming letter at a time.   

The guys at MicroScale clearly hate Pennsy modelers and want them to work as hard as possible.