Author Topic: Building a 3D Printer, RepRap Mendel Prusa2 by craynerd (Read 53353 times)

shipto · « **Reply #50 on:** June 16, 2012, 07:12:23 PM »

good stuff your printer is producing I looked at these ages ago but didnt think them capable of such work.
although the filaments are expensive from what I have seen what we need is a machine to extrude filaments from old plastic bottles etc. even better just make something to chew them into tiny grain and feed that from a little hopper.
come on modders we can make the reprap cheaper to run if we put our minds to it

machineshed · « **Reply #51 on:** June 17, 2012, 01:59:10 AM »

sounds like a challenge!

DMIOM · « **Reply #52 on:** June 17, 2012, 04:04:57 AM »

Quote from: shipto on June 16, 2012, 07:12:23 PM

good stuff your printer is producing I looked at these ages ago but didnt think them capable of such work.
although the filaments are expensive from what I have seen what we need is a machine to extrude filaments from old plastic bottles etc. even better just make something to chew them into tiny grain and feed that from a little hopper.
come on modders we can make the reprap cheaper to run if we put our minds to it

Problem I would forsee is that any such intrinsically non-homogenous material wouldn't have one melting point, would have variable adhesion/cohesion, would have different viscosities, and would extrude at different rates (and I hate to think what might happen if there was a Gold Top foil label left in there

)

Only way this might be a go'er is if you either made a lot of components yourself you had to scrap, or you bought material of guaranteed quality (off-topic : Ade - have you managed to get the wicks out of all that 100kg of candles you bought yet?

).

Nevertheless - here's a start - the Schred which can get as far as making sheet material. Now I also seem to recall someone on. I think, the Model Engineer site, who was building a replica of the aluminium extruding plant he had previous worked at .....

Dave

shipto · « **Reply #53 on:** June 17, 2012, 05:43:31 AM »

what about something like http://news.thomasnet.com/fullstory/Plastics-Extruder-suits-product-development-applications-21881

matnewsholme · « **Reply #54 on:** June 17, 2012, 11:20:08 AM »

Chris

couple of questions. Did you manage to find a set of build instructions specific to prusa iteration 2?. Every set I can find show two plates for y axis whereas iteration 2 and yours only use upper plate and mount belts to lower side of it. Also what thickness did you use for this plate? I'm thinking 9mm MDF but maybe 12mm would be better?.

Cheers

Matt

AdeV · « **Reply #55 on:** June 17, 2012, 02:41:49 PM »

Quote from: DMIOM on June 17, 2012, 04:04:57 AM

(off-topic : Ade - have you managed to get the wicks out of all that 100kg of candles you bought yet? ).

LOL - No wicks Dave, I don't know what the wax actually comes out of (or why there's quite as much available as there is), but there's no wicks in it

raynerd · « **Reply #56 on:** June 17, 2012, 05:08:04 PM »

Hi Matt
No, it is a PITA!!! There are no clear instructions for the iteration 2 and the thing is, there are so many different parts that the instructions would change so frequently! The thing is, that when you look at the i2 Prusa, it says a positive as better documentation!!!

Unfortunately, I too struggled like hell to make sense of all the parts I had whilest looking at the manuals for the original Prusa. I`m very confident that I`ve put mine together as I should have so best thing you can do, is download: http://garyhodgson.com/reprap/2011/03/prusa-mendel-visual-instructions/
...and use the photos on here and the web to see the slight changes. Notice things like the threaded rod for the cross braces under the bed are held at the TOP of the bar clamps rather than dangling from the bottom... small little things like that!!

The biggest changes are the bed. I presume you`ll be going for a heatbed right (at only £13 extra, you would be crazy not to as it is a PITA without, and instead using blue masking tape and trying to rip your parts off!), basically you just mount the heatbed pcb on 4 screws on the ply or MDF bed.

Regarding material. I used 6mm ply and it has warped due to the heat of the heatbed. However, if you use thicker, your increasing the weight. These things move at quite a fast rate (and still take ages to print!!) and the bed has to be pretty light or it`ll struggle. I`ve seen someone try 3mm aluminium sheet and quickly changed it because it was too heavy. People seem to be having luck with some sort of perspex... I`ve forgot the name, it isn`t very expensive but it looks nice, is fairly light, rigid and doesn`t warp with the temp of the heatbed (60-100 deg C about 6-10mm above the bed) . I`ll try and find you the name of that material as I`m going to pull my machine apart in the next weeks and make a few changes - replacing the ply for this will be one of them.

Good luck with it.

Quote from: matnewsholme on June 17, 2012, 11:20:08 AM

Chris

couple of questions. Did you manage to find a set of build instructions specific to prusa iteration 2?. Every set I can find show two plates for y axis whereas iteration 2 and yours only use upper plate and mount belts to lower side of it. Also what thickness did you use for this plate? I'm thinking 9mm MDF but maybe 12mm would be better?.

Cheers

Matt

HS93 · « **Reply #57 on:** June 17, 2012, 06:18:27 PM »

was it Lexan they are using for the bed, can you still get Paxolin in thick sheets ? or how about stick on reflective foilon top of the ply as used in engine bays then put the heat pad on? the tape can be got in wide rolls and can be polished down flat. or how about carbon fiber sheet I use to buy it in bigish sheets for model car chassies that was very flat and should take that kind of heat.

Peter

NickG · « **Reply #58 on:** June 18, 2012, 12:50:53 AM »

Hi Chris,

Just found this - not normally my cup of tea, have always been intrigued how they work but strangely never bothered looking before ... it's amazing, as is the quality of the parts you're getting off - can't quite believe it!! I guess they're actually quite strong due to the way they're layered up? I haven't read all of the text yet so apologies if it's all explained but how do you programme it? Some sort of 3D CAD format?

Well done, you must be well chuffed with it!

Nick

russ57 · « **Reply #59 on:** June 18, 2012, 02:24:31 AM »

ron thompson
http://www.plansandprojects.com/My%20Machines/Prusa_Mendel1/

has built his own filament extruder...

raynerd · « **Reply #60 on:** June 18, 2012, 06:53:13 AM »

Peter, Lexan, that is the one! I like the idea of the idea of the carbon fibre sheet - is it pretty lightish (to be honest, lexan is fairly heavy!)? I expect it would be expensive, I`ll have to google it tonight and look for some when I get home... yes, I like that idea of carbon fibre.

NickG - process is a little complex to get your head around at first. The printer uses a Arduino Mega as the processsor and then uses a firmware which is all free, either called Sprinter or Marlin. This is simply just an Arduino code that you programme to the Arduino over USB (all very easy). You then download a free piece of software called Pronterface/Printrun. This software communicated with the Arduino through the firmware and tells it how and what to run.

Arduino Mega --> loaded with Sprinter/Marlin --> Pronterfaces connects to Arduino through Sprinter/Marlin firmware

To actually make something, you need to create a 3D object in any CAD package like Solidworks OR the FREE Google Sketchup. Save/export the file as a STL. A 3D printer simply prints a layer at a time and keeps moving up and prints another layer. So you then have to slice the STL file/object into layers so it can print each layer and generate the G code. A FREE piece of software called Slic3r (slic3r.org) slices your object and outputs the G-code which you then load into pronterface.

CAD Package e.g Sketchup create object --> export as STL -->slice STL using slic3r --> generates gcode --> load into pronterface.

All dead simple once you get your head around the process and free!!

Regarding the strength of the models - I was supprised how strong the plastic is as just a 30% infill. Make something at 70-100% infill and it is really tough!

NickG · « **Reply #61 on:** June 18, 2012, 01:32:33 PM »

Cheers Chris, very clever stuff ... even my wife was impressed

, will be showing Yoda to the boys later!

matnewsholme · « **Reply #62 on:** June 18, 2012, 01:36:09 PM »

Quote from: craynerd on June 17, 2012, 05:08:04 PM

Hi Matt
No, it is a PITA!!! There are no clear instructions for the iteration 2 and the thing is, there are so many different parts that the instructions would change so frequently! The thing is, that when you look at the i2 Prusa, it says a positive as better documentation!!!

http://reprap.org/wiki/ABSPrusa

Chris

After a bit of digging found this set of build instructions. not perfect but at least they show single lower plate details. Cant do much now til parts start arriving.

Matt

Edit: Fixed link. Don

jgroom · « **Reply #63 on:** June 18, 2012, 03:02:51 PM »

Aaaarrrg, hooked me too.....

Where I'm at so far....

Waiting on delivery of drill rod, motors, and electronics. Then the fun begins.

Cheers

Jeff

raynerd · « **Reply #64 on:** June 18, 2012, 03:15:56 PM »

Haha, looking like this thread is hooking a few of you in!!

If anyone wants parts sets, please let me know...

jiihoo · « **Reply #65 on:** June 20, 2012, 09:01:33 AM »

Quote from: craynerd on June 18, 2012, 06:53:13 AM

Lexan, that is the one! I like the idea of the idea of the carbon fibre sheet - is it pretty lightish (to be honest, lexan is fairly heavy!)?

Lexan is polycarbonate http://en.wikipedia.org/wiki/Lexan http://en.wikipedia.org/wiki/Polycarbonate. If "generic" polycarbonate is ok, then it should be quite easily available.

Nothing wrong with carbon fiber either. Anything made from carbon fiber is cool and adding a carbon fiber part to anything makes it cool

.

Cheers,

Jari

raynerd · « **Reply #66 on:** June 20, 2012, 09:04:15 AM »

Quote from: jiihoo on June 20, 2012, 09:01:33 AM

Nothing wrong with carbon fiber either. Anything made from carbon fiber is cool and adding a carbon fiber part to anything makes it cool

Jari

Yea, I don`t have a clue of the properties but it certainly sounds cool!!

Chris

AdeV · « **Reply #67 on:** June 20, 2012, 09:27:40 AM »

Carbon fibre, when used with proper resins and baked in an autoclave (aka: oven) makes very strong yet very light parts. You can't extrude carbon fibre because it doesn't melt. You might be able to extrude plastic onto a carbon fibre mat, but unless it soaks through, bonding the plastic into the mat, I can't see the point. Normally, carbon fibre is laid in the same way as fibreglass (or glass fibre mat, as it ought to be called).

raynerd · « **Reply #68 on:** June 20, 2012, 10:00:02 AM »

Quote from: AdeV on June 20, 2012, 09:27:40 AM

Carbon fibre, when used with proper resins and baked in an autoclave (aka: oven) makes very strong yet very light parts. You can't extrude carbon fibre because it doesn't melt. You might be able to extrude plastic onto a carbon fibre mat, but unless it soaks through, bonding the plastic into the mat, I can't see the point. Normally, carbon fibre is laid in the same way as fibreglass (or glass fibre mat, as it ought to be called).

Ade, not sure what you mean

I don`t think anyone is talking about extruding carbon fibre!! We are talking about using carbon fibre for the base plate under the heatbed so that it doesn`t bend or warp. I`m currently using 6mm ply and it has bent like hell so it need changing. Peter suggested Carbon fibre or lexan.

AdeV · « **Reply #69 on:** June 20, 2012, 10:13:37 AM »

Sorry, brain-fart time....

C/F would need to be properly shaped to be rigid; but it should be dead light & would take the temperature easily without warping.

j45on · « **Reply #70 on:** July 01, 2012, 01:08:37 PM »

Looking good Chris

I finally got my 3d printer a printrbot+
One of my printed pulleys has failed along with a extruder gear and it looks like the heated bed has blown a trace burning off the solder mask.
I have had it two weeks and not managed to print anything yet

raynerd · « **Reply #71 on:** July 01, 2012, 03:37:50 PM »

Jason, oh dear, seems like you are having a tought time with it! I must admit they are pretty tempremental and mine has taken a lot of tuning to get it fairly reliable. Let us know when you get printing!!

Chris

John Stevenson · « **Reply #72 on:** July 01, 2012, 04:05:18 PM »

Jason, I thought you were building one from a kit ?

j45on · « **Reply #73 on:** July 01, 2012, 04:15:07 PM »

Hopefully they will replace the failed parts , I have emailed them.
It was a kit John different to Chris's here is a picture ( not mine, mine is in pieces

)

John Stevenson · « **Reply #74 on:** July 01, 2012, 04:22:43 PM »

Realised after I had sent the message the kit I was thinking of was a laser cutter wasn't it ?

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Author Topic: Building a 3D Printer, RepRap Mendel Prusa2 by craynerd (Read 53353 times)