My Mendel Build

After a fairly spontaneous decision, I've teamed up with my dad to build a mendel. This project is going to be a rapid one, seeing as I'm about to start my Masters next week I think I've got 2 months before my uni workload is going be ridiculous! I'm studying engineering (Aeronautical) at The University of Leeds and I've managed to get the backing for the head of teaching to get full access to workshops ect. This means that if I need to i have access to CNC lathe and milling machine as well as a wire erroder for more complex shapes should I need it.

The uni also has a 3D printer so i will be making the parts from ABS out of that, uni has accounts with a few suppliers and an educational discount and its likely that hardware will either come from farnell or RS. I've done a fair bit of reading so I'm happy that i know how the machine works and the control systems associated with it. I'm hoping to make this from a scratch, only buying in parts when I don't have the time to make them myself. An exception to this might be the electronic, although I'm comfortable designing circuits and can simulate them in SPICE i think that in the interests of saving time they are likely to be brought in. This build in general should be relatively cheap as I want to know 1st hand how accessible the technology really is, but money will be spent on quality equipment. The saying 'buy cheap, buy twice' is very true so there is likely to be some extravagant purchases along the way!

Due to time constraints this will be an off the shelf 1st draft to iron out the inevitable issues that i will encounter over the build. Long term this machine wil go to my Dad since he's sponsoring the project, but i will make a 2nd huxley sized one similar to the hydraraptor, as in it will be developed to make small parts very accurately using linear bearings and precision parts, again like the hydraraptor speed will be sacrificed for accuracy. The aim is to develop a printer which can print in 0.05mm layers and have 0.01mm positioning accuracy in all degrees of freedom since this is what the commercial HP printer at uni can do. Rome wasn't built in a day and this project won't either but I'm hoping in 2 months to be printing on a current revision Mendel!

All that is irrelevant now though, but will get covered in the future! Currently I'm only focusing on the printed parts as my account hasn't been created to buy the rest of the hardware. As many have pointed out this forum and community has a wealth of information available but I'm struggling to get find complete model of the latest revision. I'm hoping to submit parts for manufacture tomorrow so would like to know what the latest proven revision is and if there are any choice upgrade I should do from the start. The parts need to be submitted in *.stl format although I'm hoping to get a solidworks assembly made tonight to check it will fit together as a virtual dry run for the actual build.

Potentially a very quick answer, are these parts all i need printed for a Mendel or should i be swapping things and using any modification. If i should make changes could you explain what they are and how they benefit the print quality or reliability of the machine.

This is the first build log I've ever done so bare with me over it, I apologise in advance for any grammatical mistakes ect! Pictures will arrive when I remember to take them but i cannot guarantee the quality my ageing compact will give!

Looks like you are thinking about building the Sells Mendel. I'm starting a Prusa build myself, everywhere I look I see recommendations to build the Prusa, so that's what I'm going with.

The Prusa has much less plastic parts than the Sells Mendel and is far less complicated. There also seems to be a lot of Prusa builds out there.

Here's the wiki page for the Prusa: http://reprap.org/wiki/Prusa_Mendel

Instead of Wade's Geared Extruder, I'm planning on making Greg's Hinged Accessible Extruder.

I've been looking around at all the build logs I can find, here are some that I've watched:
RepRapLogPhase Prusa Build Walkthrough (multiple videos)
GeoDroidJohn Prusa Build (multiple videos)
HacksBot.com Build Log (multiple videos)

Yes, especially if speed of building is a key, go for the Prusa Mendel instead.

Spend some time around wiki and forums before buying anything, compare, ponder, and then go !

Thanks for the advice DeuxVis, less haste and more speed! But due to the time scales I can't sped too long researching! My goal in the short term is to get a working 3d printer which can print gearing reliably. Past that I'm happy to tinker in my own time over it and eventually make my 2nd Prusa with the improvements I can come up with (if there are any!).

After showing the 3D printer technician the parts list for a Prusa it looked like the Uni printer, although very good, is very uneconomical to run and as such would end up costing upwards of £300 to make the parts, plus the time it would take to print all those parts as the guy said he'd do it in between research jobs. All in all a bit disappointing. I really wanted to do this all from scratch as much as possible and its a bit of an early blow that the uni can't produce the parts for any where near market value, which I judged to be around £80 from eBay. On the plus side I can afford to replace the odd part from uni and to upgrade parts when I need.

So for UK based sellers, who should I get the plastic parts? Obviously they are not all made even so who are the best people to get them off? Ideally, since this is the basis of the printer, I would like ABS parts due to there higher strength and heat resistance. Any suggestions?

The hinged extruder does seem like a good idea, and thanks a lot for the videos. I'm pretty handy at making things and after building a test rig over summer and it looks pretty straight forward. Again, much easier than the Isaac to assemble and has much fewer parts to print.

Nophead

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