Monday, 12 September 2011

The scrooge's guide to part selection

I followed 4 rules when purchasing my parts:
  1. Save money on items.
  2. Save money on shipping.
  3. Save time sourcing all the items.
  4. Don't try to make things I don't have tools for.  
In retrospect I should have added:
  1. Get good value.
  2. Don't be lazy with research.
  3. Don't rush.
Research
Do lots.... And then do some more.
  • Visit the forums.  
  • Get on IRC and ask questions.  
  • Look through the wiki.  Pull up a chair and get comfortable because you're going to be here a lot.  There's a buyer's guide (I just realised how important that link is) and an Australia supplier list.  
  • Get in touch with local reprappers.  Maybe you've got a nearby hackerspace that could help you out.  
Hotend (Wildseyed is AWESOME!!!)
Wildseyed's simple hotend
After asking around for opinions about hot ends (the one time I wasn't lazy with research or rushing) Wildseyed himself offered to send me a complete hotend of his own design.  Sir, I'm sincerely thankful for your generosity.  I'll be posting my experiences with his hotend when I'm up and printing, maybe try to source the parts and make my own.

Motors 
I got some used NEMA17 motors from ebay.  They work and they're cheap, what more can I ask for.    They're even better value considering I bought 8 for less than AUD$60 delivered.  That leaves me 3 extra for a small CNC :-)  I just hope they have enough torque for the extruder.  The only down side is that the pulleys harder to remove than something really hard to remove.  So you may want to pay extra to get seller to remove them for you.

Electronics
Full RAMPS Kit + SDRamps kit from RepRapWorld in the Netherlands.  They were running out their RAMPS 1.3 kits for the remarkable price of ~AUD$115 (sorry, sold out now).  They have great service and are always promptly replying to my emails.  I highly recommend them, but be warned that the package doesn't track once it leaves the Netherlands (2 weeks of nail biting taught me that).

Printed Parts
The printed parts and vitamin set came from a seller on eMakerShop.com.  The parts were ok (just ok) - they needed a lot of work to clean up (more on this in a later post) but I guess they are functional. And they had ABS bushings (#!@!).  If I had done more research (rule 6) and not rushing (rule 7) I would have gotten better value (rule 5) for my money getting a set of parts from Greg Frost for a little less (but I'd have to make the thicksheets myself and source all the nuts and bolts etc.) Oh well, I'll be printing my self a new set of parts soon anyway.

Rods
A few Aussie reprappers seem to be buying their rods online.  $20 for shipping?  err, don't think so.  I sourced my rods locally.
  • Get smooth rods from stainless steel merchants.  They'll sell it in really long lengths, mine were 4m long.  Be prepared to tape (that's right, use duct tape / electrical tape) the rods to your roof rack to take them home. Ring around, I got mine for $3.30 a metre.
  • Get threaded rods from fastener shops.  They sell by the metre.  Mine cost $5.  Ring around, prices vary quite a bit.  While you're there get your nuts and bolts and washers.  Don't go to Bunnings (check the prices yourself though, don't take my word for it).  I was quoted $8 for a pack of M8 nuts, I think that's half the price of Bunnings. 
  • Use the phone.  Yellow pages is your friend.  Most of the places that sell this stuff don't have web sites and the ones that do don't usually have a price list.
  • Most industrial suppliers are closed on weekends.
Misc
  • Kapton tape and PET tape from dealextreme.com.  It's cheap.  It works.  The kapton held up no matter how much I stabbed it with a hot soldering iron.  Your mileage may vary though.
  • Jaycar is expensive for most components.  Make sure to check element14 and rs for prices before buying anything from Jaycar.  All I got from Jaycar is a flux pen which I needed for soldering the SDRamps board.
  • Power supply - doesn't everybody have at least one ATX power supply gathering dust in a dark corner?

No comments:

Post a Comment