Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.


Messages - Harold Downey

Pages: 1 ... 9 10 [11]
151
Work and Events / Re: WW&F No. 11 - Official Work Thread
« on: January 14, 2015, 11:03:54 PM »
Then I added two thickeners on the ends,  as well as the top and bottom flanges.  These flanges are laminated up, then tapered with the appropriate draft.   I glued these on, and put in some screws from the back to make sure they stay on. 

152
Work and Events / Re: WW&F No. 11 - Official Work Thread
« on: January 14, 2015, 10:59:27 PM »
I am going to start a short series of posts on the pattern for the rear frame extension casting.  This is the second largest pattern for the locomotive.  Overall it is 56 1/2" wide by 15" tall and 20 3/4" long.  Estimated weight of the finished steel casting is 521 lbs.

The function of this casting is to connect the forward frame to the rear frame just in front of the firebox.  If you recall for #9, it needed a similar casting when it was rebuilt. 

The first thing I did was take the CAD drawing and add machining allowance and draft.  Then I scaled it by the expected shrinkage of 1/4" per foot.   

The plan that Alan and I worked out for this casting is to break it into three parts, and to back it up with what is called a 'follow board'.    This allows the pattern to serve as its own core box (to form a core), and to be able to extract the pattern from the sand mold.    This will become more clear as the build progresses.  Just follow along and see. 

I started with the largest piece, a rectangular piece of plywood, laminated up to 1 1/64" thick, 2 degrees draft on all sides, and three 8" holes.  The holes are reinforced by a 3/4" wide ring, which also gets 2 degrees draft on both sides.



153
Work and Events / Re: WW&F No. 9 - Official Work Thread
« on: November 13, 2014, 02:15:49 PM »
Here is a better comparison, both from a similar oblique view:

154
Work and Events / Re: WW&F No. 9 - Official Work Thread
« on: November 13, 2014, 02:14:51 PM »
A new pattern for Number 9 number plate that reproduces the plate used by the WW&F.    Compare with the historical photograph from the WW&F roundhouse machine shop.

155
Work and Events / Re: WW&F No. 11 - Official Work Thread
« on: October 07, 2014, 08:16:56 PM »
Finally the nearly finished core box for the main core.  Since it is so big and complex, I tried something new:   I made a positive of the core (shown to the left of the core box), and used that to make a plaster mold.  The plaster mold is the core box.  It took nearly 50 pounds of plaster, and I had to do some repair work after making the casting to fill voids.  Then I sealed it with a few coats of polyurethane.  Finally it will get a nice shiny coat of orange as well. 

Thanks go to Alan for helping me figure out how to do this, and also all his helpful jigs and fixtures for making 2 degree draft features, and many other tricks and shortcuts. 

156
Work and Events / Re: WW&F No. 11 - Official Work Thread
« on: October 07, 2014, 08:16:19 PM »
I am nearly finished with my first pattern for #11 - the lead truck center casting.   It is pretty complex -- there are three cores, one of which is very large.   

First a sketch in isometric view of the casting as it should look when finished.

Then two views of the main pattern with the two small core boxes.  Orange in this case indicates where cores go on the pattern (called core prints), and the core boxes, which are similarly color coded.

157
Work and Events / Re: WW&F No. 9 - Official Work Thread
« on: August 16, 2014, 12:25:32 PM »
Much work has been done this week, especially with the injector piping.  Please go to the museums' facebook page for photos and to find out who put in A LOT of time on the project.  Hint: His name begins with J but it's not Jason  ???

Stewart,

Could you please post some of the photos here as some of us don't have a face book account and with out one they will not let look at the photos.

Andre

Andre,

Writing as a member of the facebook illiterati <grin>, I can understand why you think you need an account.  I first tried to find it on facebook and it did seem to insist that you sign up before letting you in.  Fortunately, that is not the case.  My best method to view the WW&F facebook page is to go to the official WW&F website, and click on the facebook icon (the lowercase white f in a blue circle), and it takes you right there.  Click on any picture to view the whole album. 

Harold

Pages: 1 ... 9 10 [11]