Sunday, February 28, 2010

Updates for shopping

I have got some great feedback on that last post about the good places to shop. I will keep it up to date and repost it every month or so. Don't mind PM or comments if you want stuff added. BTW if someone offers a better deals in my opinion I will drop the bad deal and add them. This is my list of places I shop (or would shop).

Good deals for cranky robots.




We all have stuff that we have to buy to feed our machines, and there are some really good places to buy the stuff. Just wanted to call out a few of them.

Kapton Tape

8mm apton Tape at Deal Extreme for $2.19
24mm Kapton Tape at Deal Extreme for $4.20
101.6mm Kapton Tape at Tape Depot for 1mm for $92, 2mm for $105

Cool thing about the 100mm roll is that you can Kapton your Makerbot build plate for $.33, or your Darwin/Rapman for $1.50.

100mmx100mm Kapton sheet pre cut at Makergear for $3.50 (Don't have to drop $100+ dollars for something you will rarely replace if treated right).

Motors

Pololu is hands down the best source for stepper motors. They have tons of nema 14, 17, 23 and basicly any size in between in stock. They also allow you to select the torc you need. Shipping was only 5 dollars for a stepper motor to my house in USA,NC. Same $12-20 dollar price range all the lower price stepper motor retailers sell for, but this one ships from inside the US.

Phidgets has a great selection of Stepper motors. NEMA 14 & NEMA 17 steppers for $15 a piece, NEMA 23 for $21. Quick shipping and the motors look perfect (I have not ran my NEMA 14 yet, so can't say how well they WORK though).

Erbyers over at ebay consistently has NEMA 17 motors for $7. They are basically the same stats as the Makerbot NEMA 17, with a double shaft.

Kysan Gear motor sku 1156006, same gear motor sold by Makerbot. Kysan shipments usually take a long time, but if you need the gear motor, and Makerbot's out of stock, good backup way to get it. (If Makerbot is in stock, buy it through them, that way you are supporting their business model, only use this source if they are out of stock). $15


Makerbot specific items

Makerbot has the lowest price on Natural ABS, and they are the only ones that sell 4032 PLA. They also now have 5lb rolls of RED, GREEN, BLUE, YELLOW, and BLACK ABS. Can't go wrong with Makerbot, when they are in stock.

Ultimachine sells 5lb rolls of 4042 PLA in black, green and clear. Their PLA is very inexpensive, with the clear being only $50 and colored $60. They ship quick and are great folk.

Villageplastics is a great back up place to buy plastic from. They will sell you what ever colors they are running currently without a set up fee. Also they will run What ever color you want for a $50 set up fee, plus the per lb rate. There quoted price is a little higher than Makerbot , then they charge to %3 for credit card. So it'a a great backup if you can't get the filament cheaper at Makerbot. If you are going to buy, I suggest you place your order over the phone, that way you don't have to trust your card to email. Phone # 330-753-0100

Makerbot specific items

$35 dollar heated build plate kit at Makergear, it works great, looks great (when done it looks and works like it was part of your bot in the 1st place, always a sign of a GREAT kit) and the build plate goes on and off a Makerbot just like the original build plate (no plugs, it magneticly connects like a Macbook). The kit is no harder to put together than the Plasturder. I also have to say that their heater core kit, thermistor kit, and laser cut plastruder replacement parts (wish I didn't know this) all rock the casaba. They also sell 1lb rolls of LOTS of different plastics. They are great folk over there.

Electronics

As everyone knows Store.makerbot.com has the electronics in kits, and 1 off. MOST reliable source, when they are in stock.

Full set of RepRap electronics (equivalent to Makerbot gen 3) for $215, plus they include the power supply & cables, and it uses the ribbon cables like the standard RepRap. It's over in the RepRap forum. Also they sell out of their ebay store. The lady that's doing it claims to have plenty in stock and could ship VERY quickly. **btw I have not bought from her yet, so Caveat emptor and all that.

Reprapsource sells the Arduino based electroncis for Mendel at their site. Unfortunately they are in Europe, with killer VAT and shipping.





Mechanicals for Mendel


J-dubs talked VXB into stocking a "Mendel kit" for $50. It actually works out as a good deal. Also VXB is the cheapest place to find precession smooth rod that I have found. Again ship quick and great people

WTTools has the cheapest smooth (non precession) rod I have found. At $4 for a 3 foot stick of 8mm smooth it's a great deal. I have 2 sticks sitting at my house, and it SEEMS like it will be perfect for Mendel. My Makerbot uses precision smooth rod, you can tell the difference, but it's not DRASTIC.

Onlinemetals is a great place to buy plastic & metal (don't let the name fool you). They have 1 foot sticks of PTFE Teflon for $5, and 1 foot of PEEK for $30. Their 5/16 Teflon is only $5 for 3 foot, makes me wonder how a homemade teflon bushing on teflon rod would work on a bot... hmmm, me things I must try that.

Ultimachine has a $250 Mendel kit (all the rod is precut!). It's everything but motors, belts, electronics, and RP.

Big Blue Saw will cut all the thick sheets for Mendel in 6mm acrylic for $43 dollars. That's 1/3 less than Ponoko, and 1/2 what I can find locally. The All in 1 cut dxf can be found at sourceforge RepRap repository inside the zip file.

Goinreverse over at the RepRap forum has made a cut and paste Mccmaster parts list for Mendel. Just enter his list at the this link.

Most other things I buy from Mcmaster .

I am sure you guys have found some GREAT deals I have now clue about. Please put them in the comments and I will add them to this blog post.


Thanks to Cyrozap

Thursday, February 18, 2010

Parifin Wax Soak for RP parts.

While playing around with some of my Mendel parts, I came across the most fun way to make SUPER dense parts that are also quick to print. I hadn't posting anything about it because I thought it was a little silly, but after a post on thingiverse, I realized this technique might help some people out.

Parifin wax is around the same density as ABS, but melts at 64C. A very easy way to cut your build times on structural components is to print an item at say .15 or even .1, basically making a part almost completely hollow.

You then place the part in a pot with melted parifin. The parifin will eventually fill the inside of the part (after about 5 minutes, depending on the part). Then pull the part out of the pot, and place it in the freezer. After about an hour take the part out of the freezer and place it in the oven. After about 10 minutes the outside of the part can be wiped clean. The part will be super heavy, like a 1 infill part, and will be structurally strong at room temp.

This technique has some advantages.

-Almost no warping, it's the infill that causes most of our warping issues
-Parfin wax is available in all countries, and cost $3 a lb
-No odor
-Cuts print times by a significant amount.
-If you are really cheap, you can get the Parifin wax out of the part by placing it an oven at 100C, and just let it drip out.

Disadvantages:

-Parafin is very flamable, and if someone put a match against your part, well by by house.

-Would not be suitable for extruder parts, but would be suitable for all parts that are not related to either the motors, or extruder.

Sorry no video, my camera has been stolen by my 3 year old daughter.

Saturday, February 13, 2010

Pricing the Mini Mendel




I will be going ahead with both my Mini (M3) Mendel, and my M4 Mendel in parallel. So I figured I would do some US costing for a Mini Mendel vs it's M4 big brother. Just a reminder the M3 Mendel is not in development, and I am doing this more out of curiosity than trying to get a fuctioning printer out of it.

Threaded Rod:

Cheapest place I have found for M6 threaded rod is a local fastener company that sells it for $3 for a 1 meter stick (zinc coated). That would mean I need 6 sticks of rod if I cut them in this pattern. $18 plus sells tax

1 4x244
1 270,230,257,230
1 270,230,320,84,82
1 244,244,183,183,102
1 320,102,102,102,84,84,84,82
1 82,82,82

Smooth Rod:

Considering we are using bearings the rod doesn't have to be quite as good as bushing rod. I will be going with wttool.com. They sell a 36 inch (914cm) long 6mm smooth rod for $2.70. That's 1/10 the cost of the vxb linear motion rod which runs $25 for 30 inches. at 36 inches I will need 2 bars. About $6 dollars plus shipping

1 224,224,272,
1 275,275,272

Fasteners:

Local supplier usually beats bolddepot.com, but without the shipping costs associated with them. Luckily I have a good bit of M3 nuts, washers, and socket caps left over from my Makerbot, but I plan on costing out all the M3 so I can have a good idea of the real cost of this project. I don't use nylocks, I use lock tight instead because I am very forgetfull, and always end up stripping them. Costs without Nylocs would be $54 dollars.

m3x12 100 $5.41
m3x20 100 $5.93
m3x30 100 $8.42
m3nut 200 $4.32
m3washer 400 $7.44
m5mudwasher 17 $2.55
m6nut 200 $9.38
m6washer 200 $6.94

Steppers:

NEMA 14 motors are hard to find. The only NEMA 14 motor that I could find online was at phidgets.com for $15 dollars each. They are only 1250 g/cm, which is a little lower than the suggested 1400 g/cq torque suggested for the Mendel m4. Has anyone seen a high torque NEMA 14 stepper in the US? If I can't get a good prospect that doesn't break the bank, I might have to go with the lower torque ones. Also I plan on going with a Makerbot gear motor for the extruder, just because that's what I know.

Bearings: I usually use vxb.com because I usually can't beat their price. I came up with 4 sets of vxb 623 for $60 and 1 set of 20 vxb 626 for $25 for a total of $85 dollars worth of bearings (ouch)


RP parts

I am averaging 20-30 hours a week of print time at this point, and should have my m4 Mendel printed by next Friday. Good thing is I will be able to print ALL the parts for the m3 Mendel in 1 week! That will be a fun change of pace.

Total cost of m3 Mendel for me will be Stud $18, Rod $6, Fasteners $54, Lasercut (Don't know where I am getting my lasercut parts yet, but assuming $30 for all the LC parts), Electroncis $175 (makerbot), belts form mcmasters for $20, bearings $85 and motors $100

$500 for a fully functioning slightly larger than Makerbot scaled, belt driven RepRap is not that bad. Considering it will only take $300 out of pocket for me I think this is doable.

Any suggestions on cutting the cost?

Friday, February 12, 2010

Reviving the Ponoko Darwin






Given all the growing interest in RepRap style printers, is there interest in restarting development of the Ponoko Darwin development? See it here

I am trying to talk one of the RepRap parts suppliers into offering the lasercut parts for this printer as an off the shelf purchase. I think the Ponoko Darwin still has some things going for it.

-It's honestly the pretties RepRap built, the ability to make it out of many colors makes it so unique. Say what you will the Rapman is hot little printer

-It would be the only Darwin that could be offered "off the shelf" while still completely following the GNU licence of the true RepRap.

-Would not suffer from the limitations of the screw drive like Mcwires

-It has a fully documented wiki already in place. (see the bottom of the main Ponoko site)

-Will run off any boards that can drive Makerbot or a normal Darwin.

-Given that a McWire requires $100 worth of metal, I personally would rather $200-$300 worth of lasercut parts for a REAL belt driven Reprap

-Ponoko is hard to order from (at least from me). If I could have ordered a Darwin lasercut kit, I likely wouldn't have bought a Makerbot.

Only real downside of Ponoko Darwin is it takes more screws/bolts, and the lasercut parts are easier to break.

So lets hear it, would YOU like to see a Darwin Lasercut kit available? Please comment!

Wednesday, February 10, 2010

Shattered Plastruder, hello Epoxy

It's been an interesting few week. Finally got my Makergear heater barrel together (LOVE IT!), and the Makergear thermistor/ring terminal hack together. I managed to rebuild my barrel 4 times in 1 night, without killing any thermistors or nichrome, this is a record for me.

After coating my PLA in oil I found that it did help with extrusion, it seems to make the PLA soft enough to allow the Plastruder to hold it better. It was extruding PERFECTLY. I even got so cocky as to start giving Makerblock advice on the Makerbot Google group. Everything was going great till I started messing with the temp trying to make it work that "little bit" better. As Makerblock likes to point out, Polly is not a very nice lady.

I have broken retainer rings before, but nothing like what happened next. Every single sheet of Acylic in my Plastruder cracked, some of the sheets shattered. The retianer ring of course shattered also. I was consigned to go another few weeks without printing.


Well I went ahead and ordered all the replacement parts for my Plastruder from Makergear (wish someone would sell the acrylic pieces for the Paxtruder... Ohh well.). Plan o getting a heated build plate from them when they come available again.

I am done with PLA untill my Mendel comes online. I just can't afford to keep replacing parts. I like Rick at Makergear, but I really don't want to have him name is 1st yacht after me.

Started printing a Prinstruder, and have hit the Mendel Printing full blast. I have been printing for 14 hours straight, hope to get another 20 in before I go to work this weekend.


Google RepRap feed is almost up to 70 feeds now :) woho!