Thursday, May 29, 2014

My first Train

Here is the prototype of the train that I have been discussing in the design process.  The good news about the prototype is that it can be stained and used.  If I was going to make an actual one it would be out of maple and walnut.  However this would be very cost prohibitive for a prototype.  This train is made out of poplar and oak dowels.  There are other woods used  because they are purchased parts.
It was a fun little design project. From start to finish it took about 8 weeks.  This includes drawing and building times.
This is the complete train.  Six cars and each car is about 9 inches long.  In my humble opinion it looks great.  In designing this train, I wanted something durable and age appropriate for the 3-8 year old range.  I also wanted to use only basic tools that a toy maker should have (scroll say, table saw, small router, drill press, and belt sander). The only tools I used in addition to the list was a miter saw and band saw.  Both I could have used other tools but for ease I used the others.  It passes the durability test.  My kids used some of the cars as a riding toy. It is big enough for the kids to put things in it and push it a long. 
The Locomotive 
The great thing about this engine is that I did not need to buy a lathe for this project.  The bad thing is that I was not able to buy a lathe for this project.  The boiler is a turned part that was provided to me from Lowe's at a reasonable price.  My second option was to buy a wood rolling pin and cut it to size.  It just would not have looked as good.  Hardest part of the locomotive was proportions.  I wanted to make it the biggest car.  but it did not look right until it was reduced in length.  The cabin was made slightly larger.  I tried putting bigger wheels on it and that didn't work.  So this is the final design.  The roof and the cow catcher are the only parts that I used the band saw on.
Sorry for the green in the picture.  It is not that green in the person.  It is the light and poplar.

The Tinder Car
This was a relatively easy car.  There is not anything fancy about it
The Box Car
This was a fun little car to build.  There really isn't anything fancy about it.  The door is big enough to fit things through and the top has a roof to put things on top.  This car is where I realized I should have offset the sides.  If I made the middle section and top different sizes, the middle would not have looked so crooked.
Cage Car
I thought this was going to be an easy car to assemble.  I drilled everything together so the holes would line up and all the dowels were cut to the same size.  The problem was the dowels are a tight fit and not perfectly straight.  It took a little bit of work but it came together.  Next I will round over the ends of the dowels so the go in easier. It is an easy process of chucking the dowel in a drill and running the end at an angle on sandpaper.
Flat Bed Car
Another pretty basic car.  It takes the roof from the box car and puts it on a chassis. 
No matter how hard I tried to make this the smallest car it wanted to be the same size as the others.  The main feature I wanted on this car was the balcony.  It also proved to be the most troublesome.  I ended up changing  the balcony in the final drawings so the two corner posts do not go to the roof.  When trying to assemble the balcony I broke it twice.  I ended up drilling the thru holes larger then the dowel so that I was not pushing it through. That solved the problem but it was still a pain to remake parts.
Here are a couple of pictures of some of the details on the train.
Top roof detail of the cage car and caboose
Decoration around the wheels
I drilled through the floor to set the dowels.  It made it easier to assemble.
Fun little design.  It is a little bigger than I thought. Each car is about 9" in length.  Pretty much all the joints are re-enforced with dowels.  I was surprised of how much dowel I used.  It makes for a very strong toy.

Tuesday, May 27, 2014

Design Process Part Three

Now is the time where the decision is made to make it or throw it out.  The questions that I answer are relatively basic:
  • Do I want to make it?  Putting it all on paper is this something that I want to make or has it lost its luster or drive?
  • Can I make it?  Is the design too complicated to make, are the parts too dangerous to make or there are too many things that I do not know how to do?  This is just a question of safety and capability.
  • Is it going to fill its purpose?  I really don't want to make something that will just get by for a short season.  I do not want a piece of furniture or toy that will only be temporary or break after a little bit of use.
If the project is still ago then print out drawings and buy lumber to make prototypes or if confident just make it.  I like to have space on my drawings to make notes and changes as they come up.  If I am prototyping I work in poplar and oak.  These are less expensive woods and easy to work.  It also has the contrast that to show with difference between species.  This gives and over all look of a project and if contrast adds or detracts from the project.  These woods are also less expensive to make mistakes on.
Now it is making the parts and assembling.  Take notes on the drawings of things that come up, either wrong dimensions or changes that would make the project look better.  For example, the train cars looked better with the sides inset on the floor  than flush.
This basically is to test the fit of the parts and how everything comes together.  This process identifies the potential parts that maybe difficult to assemble or impossible to assemble.  The caboose and cage car were interesting cars to build. Even though the holes lined up it was still a pain to get all the dowels to line up and in the holes.  It made it easier to round the tops of the dowels to guide into the holes.  The caboose I thought could put in the put the longer dowels in after I put in the balcony.  I ended up breaking the balcony.  So I changed the drawing so the dowels were all the same length.
Once the prototypes is done make it how it was designed.

Tuesday, May 6, 2014

The Design Process Part Two

At this point it should be nice to have the concept project on paper.  My mind will not sleep if there is a design stuck there until I have it on paper.  This way I know that I will not forget it.  Just a final note on sketches, I write notes on the sketches,  These notes could point out design elements that I feel are important, questions or concerns I have about assembly, things that I do not have quite figured out, or materials needed for the project.
At this point I take my time and put the sketches into a 3D modeling system.  I am lucky enough to be able to use Inventor through my work.  The other popular modeling systems that cost money are Solid Works and Pro E.  The industry standard for the garage shops is Sketch- up.  It is a free drawing package from Google.  There are others that can be found on the internet.  When I first started I drew everything out by hand and to scale.  It was a fun little practice but if I ever made a mistake it was a lot of erasing.
The reason for putting it into a modeling program (or do a scale drawing) is to look at proportions and see how parts fit together.  In the project that I am working on now, I do not really like the caboose.  It looks big but it fits in the design of everything so I am leaving it the way it is.  The locomotive was a different story.  I wanted to be the biggest part of the train but the boiler (which is a purchased furniture foot) was too small.  No matter how I tried to make it bigger it just did not look right.  The wheels didn't look right  and the cabin looked funny.  My final design is a lot smaller but looks good in the series. If I skipped the step of making the scale drawing, I would have been very disappointed and wasted a lot of wood. 
The second reason to make scale drawings is too make prints of the parts.  It is a lot easier to make something after knowing it will all fit together.  Individual part drawings allows me to check off parts when they are cut and it is also easier to figure out what is needed for the project.
The other neat thing about putting a project in 3D space is seeing how it is all going to be put together.  This is where all the problems seem to arise and then get figured out.  Some of the common things that I figure out in the model are:
  • Wheel spacing.  The important part of making a wheeled toy is that all wheels work.  They can be all off center but they all need to roll.  From a personal point, I want them all to touch the floor at the same time.
  • How parts come together.  There are a ton of different ways of joining parts together.  This is where I decide what joint is going to best for assembly and hide mistakes.  It also helps formulate how the procedure on what parts to make first, when the sanding needs to be done and should I pre-finish parts.
  • Proportions as noted above.
  • This is also where I figure out how I am going to make each part.  I try to make the parts how I would machine them.  Take the cow catcher on the train, for instance.  I started with a larger block of wood.  First cut the back angle.  Then I drew out and cut the triangle portion on the front.  Through the modeling process I am figuring out how to process the parts.
  • The other question that I answer is, can I make this safely?  If I am going to stop a project or go back to the drawing board it will be here.  
This model does not have to be perfect with everything detailed out. I tend to leave of hardware and profiles.  After I am satisfied with the model I will then make prints of each part and put together a materials list.  The drawings will have a room on them to take notes for when the project is going to be put together.  This will lead into the next post and probably the last in this series.