Evolution of a Blog

This blog has evolved as I have as a maker. It starts at the beginning of my journey where I began to re-tread my tires in the useful lore of micro electronics and the open-source software that can drive them. While building solutions around micro-electronics are still an occasional topic my more recent focus has been on the 3D Printing side of making.

Friday, October 30, 2015

3D Printing in Air

One of the harder things to understand, or visualize, about how a 3D printer works is how it prints in air.  Or rather the fact that a 3D Printer (of my type, a fused filament fabrication (FFF) printer) has to employ some special techniques in order to print structures that would require it to print in the air.

An FFF based printer works by laying down layer after layer of plastic in little strands of plastic that are extruded following the plan calculated by a slicing program.  In a way you can think of building in bricks as being somewhat similar.  Each line of bricks representing a line of plastic.  Consider three types of structural elements:

  • An overhang.  An overhang can be built using bricks as long as each course of bricks that extends into the overhang is only projected into that overhang a little beyond the previous course.  The next course of bricks will then keep the first course from falling.  Allowing the concrete to set before going to high is a good idea.   The same principal applies for building an overhang from extruded plastic.  A little at a time with active cooling so the plastic sets.
  • An square opening (e.g. for a window or door).  In this case the brick layer has to use a support above the opening on which the courses of bricks are layed.  An FFF printer is capable of building it's own support by something called bridging.  The slicer knows that it needs to string threads of plastic across the opening and that is exactly what it does (using various tune-able settings to make it work).  Subsequent layers of plastic are then layered on top of the bridge.
  • An arch.  For this type of shape a supporting structure must be built on which the brickwork is layed in a pattern where once the mortar has set the structure will be stable and the support removed.  An FFF printer can also print support structures that allow for complex shapes to be printed without concern for building layers or bridging a square opening.  There are a number of downsides to this approach however.  It takes a lot of extra time and plastic and all that extra plastic has to be removed...often leaving blemishes on the model being printed.

Saturday, October 24, 2015

3D Printed Tank Related Bling (Flames of War) for Sale!

What started as a way to experiment with my new 0.25mm nozzles ended with having a selection of Flames of War bling for sale.   Note that there is now a minimum order of 20 quid for this bling due to the effort involved with small orders.  All proceeds benefit the MS Society. (except for the Bailey Bridge which will be at 50% until it renews).

The first of these eBay sales allows you to select a custom assortment of bling that will be printed to order:

These are not very profitable items to sell as they take a while to print and the price point competition seems to be for injection molded plastic...with which a 3D Printer can not compete.  That said I would like to see someone put some of the bling to work (and maybe share some pictures)!

Comments on Pricing

When I first listed these things I offered free shipping thinking that an order for just one item would be rare.   That turned out to not be the case as there have been a lot of single item orders.  Since I practically have to pay to sell these things by the ones I tried adding postage but offering a rebate in terms of good for orders of two or more items.   Well two of two buyers either did not understand the offer or did not want to take advantage of it.   Given that one of these buyers was for a single item I do still feel vindicated in taking some kind of action.  What I have decided to do, however, is simply increase all prices by a little to cover shipping but offer these items with "free shipping".  Trust me when I say that I am glad this is a hobby not a business!  Besides, half of anything sold goes to the MS Society, a charity for a disease that is close to me.

Shipment Costs
< 5 GBP> 5 < 15 GBP> 15 GBP
United KingdomFreeFreeFree
North America2.51.5Free
Australia/New Zealand2.51.5Free
South America2.51.5Free

Sunday, October 18, 2015

Interchangeable Nozzles Still the Cat's Meow

I am still appreciating the hot end upgrade that I did on my two Ultimaker 2 printers.

The 3DSolex heater block makes changing nozzles a matter of seconds.   It makes it easy to switch between materials but I am finding it even more useful to be able to choose a nozzle size based on what I am printing.   One of the standard 0.4mm nozzles can usually be found on the printers but I love being able to switch to the 0.8mm or 0.6mm nozzles when I want to print a draft at 0.4mm or even higher or maybe a case or box for which a layer height of 0.3mm is just fine (like the one shown below).

I have started to collect nozzles so had to print myself a box for storage.  The little plastic squares remind me what nozzle is on what printer.
The top row are reserved for PLA and descend in size from left to right (1.0, 0.8, 0.6, 0.4, 0.25, 0.15mm).  The bottom row are the same sizes reserved for ABS but for the lower left which is a steel nozzle for carbon fiber reinforced filament.

My only complaint is that there is not a reseller in the UK.  I have an order in flight from the source in Norway but we are having some shipping problems (with stuff having gone astray) and I think that Carl is tired of me!   Hopefully we can get this sorted out as I want to complete my nozzle inventory primarily with additional PLA nozzles (0.25, 0.6, 0.8) so I can print the same size on both machines at the same time.

Speaking of 3DSolex.  It is not just the heater block and nozzles that I have purchased from them.  I also upgraded the newest of my printers with their steel coupler, I2K insulator to help protect the teflon coupler, and their bowden tube.  I have no way of measuring the effectiveness of these last products but based on how well the nozzles perform I am willing to go on faith!

Thursday, October 15, 2015

Not exactly a tank but related!

I have been looking for a project that would take advantage of my 0.25mm nozzle and ended up with a collection of "bling" for Flames of War miniature gamers (15mm).  I had the vague idea of selling this stuff but frankly it started to feel like work, something to which I no longer subscribe, so I decided to put these designs out on Thingiverse and just have fun with it!

Speaking of the work comment.  As saleable goods these have a very low value.  At the same time, due to their size, they require a fairly well tuned printer and some amount of baby sitting.  The equation does not work out for me!  The bottom line of my experience with 3D Printing and Flames of War is that there is probably not a huge amount of opportunity to sell things that are 3D Printed to gamers.  Namely because the competition can price their injection molded stuff too low for the printed goods to compete.   I suspect there are things that could be designed that do not exist in the injection molded world that would fetch a higher price but finding those opportunities also seems like work!

Anyway, here is what we have in this first collection:
  1. Sign posts.  Have four varients though more could be done easily (1, 2, 3, and 5 arrows).
  2. Tables. One large and one small.
  3. Radio on a small table.
  4. Tools, hammer, axe, shovel, and pick.
  5. Oil drum.
  6. Shell crates.  One open showing shells with lid, one closed, and a stack of them,
  7. Dragons tooth tank barrier
  8. Crates.  Large and smaller and stacks of four different configurations (only one shown).
  9. Belgian gate barrier.
  10. Panzerfaust, bazooka, bazooka shell bags
  11. Dug-in marker.

Here is a link to these models on Thingiverse.  Some of them will likely print fine with a normal nozzle while others might be a struggle.

These items may not be sellable as 3D prints but do represent a bit of what a hobbyist can do with a 3D printer.  I think the world of modeling is going to change as printers get cheaper and easier to use.

UPDATED on 20/10/2015

Finally got around to printing some of these items using a standard 0.4mm nozzle and was pleasantly surprised at the result.  With a extrusion width of 0.3mm the printer was able to do all but one of the pieces of bling (the pick did not print).  The stand part of the Belgian Gate is not as clean as with the smaller nozzle but the other items have good detail.