HOn30 Tribute Diesels

[KentuckySouthern]

  

[Philip]

Some serious accurate jigging goin on Bernd! 

[Bernd]

Some serious accurate jigging goin on Bernd! 

It's the only way to make sure the model comes together square and everything fits properly. Something I learned in my job.

Bernd

[deemery]

Is there a trick to bending thicker brass, etc, at a precise right angle (without a bending brake tool?)

dave

[elwoodblues]

Now, that is impressive.  Thanks for doing this step by step, their is tons to be learned here.

[Bernd]

Is there a trick to bending thicker brass, etc, at a precise right angle (without a bending brake tool?)

dave

Yes there is. Depending on the thickness of the brass either scribe a deep groove or saw cut about halfway through the brass. Flip back over so the cut is down. Then gently bend by hand over a sharp corner. Check with a square. Which way the bend goes depends on the thickness of the brass. If it's done with a saw cut you'll want the saw cut to the inside. If it's brass to maybe .015" thick and scribed keep the scribe facing out.

Go to my Suydam Engine house build where I bend a piece of brass to form an angle. About halfway down the page. Should give you the info of how to do that.

https://modelersforum.com/index.php?topic=6785.0

Bernd

[Bernd]

Now, that is impressive.  Thanks for doing this step by step, their is tons to be learned here.

Thank you Ron. Glad it is of interest and helps with ideas.

I know a lot of you modelers work more often in wood. I enjoy working with metals as much as with wood and figured I show how easy it is to work with metals also. All it is, is a different type of material and different tools needed to work with it. The concept is the same, make parts and assemble them.

Bernd

[deemery]

Is there a trick to bending thicker brass, etc, at a precise right angle (without a bending brake tool?)

dave

Yes there is. Depending on the thickness of the brass either scribe a deep groove or saw cut about halfway through the brass. Flip back over so the cut is down. Then gently bend by hand over a sharp corner. Check with a square. Which way the bend goes depends on the thickness of the brass. If it's done with a saw cut you'll want the saw cut to the inside. If it's brass to maybe .015" thick and scribed keep the scribe facing out.

Go to my Suydam Engine house build where I bend a piece of brass to form an angle. About halfway down the page. Should give you the info of how to do that.

https://modelersforum.com/index.php?topic=6785.0

Bernd

So part of the secret is nice tight vise jaws :-)  Thanks!  

dave

[Bernd]

Yes, that's one method. The vise is a machinist vice with smooth jaws. A second method is to clamp the piece you want to bend between two pieces of steel with clamps and a sharp straight edge.

Bernd

[Bernd]

Continuing on with the roof build.

I removed the two pieces of square tubing. I think if didn't work out somehow.



I bent the rood sides down to hide the roof/body joint line.





On the RRL forum a member eluded that I should elaborate on my how-to's, on what steps it takes, and techniques to take while soldering the parts together. So, with some intensive pictures count I will do that. This exercise will be the making of the roof for the second engine. I added a third rib to help hold the roof in the proper curvature. Using a jig plate with 1/4-20 holes to hold the rib down for soldering. The stir sticks insulate the brass from the aluminum plate and keeps the aluminum plate from sucking the heat from the brass.



Adding a bit of flux to the bottom of the rib.



Cutting up some short pieces of solder. I use 1/16" dia. 60/40.



Clamped the rib to the tubing and added one piece of solder.



Applying heat. (using my home-made resistance soldering tweezers)



And we have a soldered joint.



With the first side held solidly with solder, I soldered the other side.





And a test fit.



I drew the roof in my CAD program and printed it out. The paper print was glued to a piece of .010" thick brass sheet using spray adhesive. Yes, I did make new roofs for both. This is where I was confused as to the pictures I had taken. I changed the roof line on the back and front of the roof.





After cutting along the lines carefully with a pair of Fiskars scissors a file was use to trim to the line.



Next a piece of pipe was used to start the curved roof. Anything will do that is smaller in diameter than the finished roof curve. The pipe was used to start the bend. It gave a gentle curve to the roof, but I needed more
curvature.



Next, I used a pill bottle for more curvature.



A quick calibrated eyeball look said it was close.



A test fit on the roof ribs showed I had just what I wanted. A bit of a tighter curvature than the roof ribs. When pressed down in the center the roof conforms to the curvature of the ribs as will be seen in later pictures.



I started with the center rib to solder the roof on. A bit of flux. Same procedure as when I soldered the middle rib on. I scribed some lines near the end of the roof to help center the roof front to back.



Squeezed hard with the tweezers to seat the middle of the roof and applied heat.



Then it's the ends of the roof. I always start at the middle so the tubing won't unsolder from the roof ribs. If they do, nothing will move.



You can barely see the end tips getting a dull red from heat.



Foot off the pedal and let it cool while squeezing the tweezers.



Next the roof gets placed on the shell and the first bend is made to curve the roof down. The chassis has been removed so it doesn't get damaged. It takes quite a bit of pressure to start the bend. The shell flew out of me hands a couple of times.



A quick check shows that it's starting bend down. Not to detectable in the first picture.





Next I worked the bend with a piece of dowel stock until I was satisfied with the radius of the bend.



The left side of the roof overhang is a bit longer than the right. A simple file job will take care of that till the sides are even.



And the end result, two boxcabs.



That'll do it for now. Next some details will be added.

Bernd