Fundementally changing Mini Mendel in HeeksCAD

After installing my Makerbot MK5 worm gear, and a Makergear idler wheel my Plastruder has printed almost 40 hours non stop without a single hiccup, which is unprecedented for me.

In case you didn't know Makergear's version of an idler wheel is almost twice as thick as the Makerbot standard one, I honestly can't imagine anything breaking it. If you need a replacement idler wheel, get their $2 4.5mm idler wheel before you invest in one of the metal ones.

I am in the process of trying to change up the Mini Mendel to make it cheaper, especially for us Americans that can't get Metric Rod Locally.

The changes I am making:
-NEMA 17 motors, because they are easier to find, and cheaper to buy
-All 608 bearings (can be picked up at the local skate shop)
-All 1/4 inch smooth and structural rod
-M8 Z drive rod, so I can use 608 bearings.
-A bed raised on m3 nuts like a Makergear heated build plate, and a ceramic build plate from the start.
-Electronics mounted like the techzone alternate electroncis mount at http://www.thingiverse.com/thing:2174



I thought I was going to get away with reusing allot of the Mini Mendel parts... no such luck. The bearing and motor changes means almost every parts needs to be redesigned. Luckily some parts have already been moved to Openscad, so I can easily alter them to fit Imperial, such as Erik's standing feet http://www.thingiverse.com/thing:2200 , and Whosawhatsis's y bar clamp http://www.thingiverse.com/thing:3437 .



I looks like the most challenging part will be getting 360 bearing chases around a 6.35mm rod with 8mm bearings. It works, but I am having a hard time getting a printable knuckle that holds the bearings tightly.

Does anyone know an easier way to do this?

I also have a Bearing/Spring idler extruder for the gear motor I have been working on for a few weeks, but unfortunately my Heekscad was recently possessed by a demon. No matter how many times I reinstall, I can't Undo without it crashing, I can't go 15 minutes without it crashing.. Honestly if I look at it wrong it crashes, which really hurts when you get things lined up just right...



Another project I am working on is a printable rip off of the Maker Bot Filament box. It uses 5/16 rod 608 bearings, 2 wing nuts and a length of 1/4 plastic tubeing. Haven't got to print it yet, but It looks like it will work.



I haven't uploaded any of this to Thingiverse yet because they all have either not been printed, or were printed, but could be better if I do just a little more work on them (The extruder works, but the idler is off center a little).

Added after the fact:



I did make a printable Sorobansu Abacus, but my daughter ran off with my printed copy, once I reprint (or find where she hid it) I will upload to Thingiverse.

Anyway if you guys have any advice, want the design files before I upload them, or just want to berate me for my obviously undiagnosed Adult Attention Deficit Disorder, exasperated by access to a RepRap printer and free Cad programs, just comment :).

Google RepRap feed update

We are now up to 250 different feeds on the Google RepRap feed.

With this new update we now have:

Live updates of all RepRap, and Makerbot related items on Flikr, Photobucket, Picassa, Ebay, Sellsimply, & Etsey.

We are up to 7 languages covered, all automatically translated into the language you can understand best.

No repeats of older posts (something that Yahoo pipes does a lot, which I don't understand).

The feed pushs out around 20 a day, all new content, and keeps you on top of the new items being sold all over the internet. This is one of the ways I am always finding new stuff to blog about.

If you want to subscribe, just go to the right side of my website and hit preview, or go directly to the preview page.

Again if you know of any blogs I have missed, or know of some service that the community might like to get auto updates on, just drop me an email at Proxyhacklab@gmail.com.

Have fun!

Good Deals, and a little bit of Vanity

My RP parts for Mendel over at sellsimp.ly finally have bidders, they are at $155 now. I will be sending the parts out Tuesday the 6th, no matter what they are going for.

The Winston Salem Journal came over and did an article on me. They interviewed Bre Petis Also! It was fun and 3-4 locals have contacted me about the printer, hoping this helps out the Hacker Space project.

Nop Head pointed out the benefits of PET tape for printing with ABS, well Deal Extreme has 24mm rolls of it with free shipping here for $4.99 Deal Extreme PET Tape.

Price war on ABS. buy3dink.com has some REALLY cheap ABS ($30 a 5lb roll). They even carry HDPE for the old school among us for $30 also.

Digi Key has a $8 blower fan that I have fell in love with. 12V 2.28 Watt (190ma), and it pushes 8.5cfm at 41db. Not bad at all. It's 75x75x25mm, but the air port is only 25x25.

That's all the good deals for now. Putting together my Makergear High Output build plate, should have it done next week, will post a video... it looks awesome. Also I installed the Maker bot worm gear. Best $10 I have ever spent on my Makerbot.

RP mendel parts $200? I hate Ebay

If your interested they are at http://sellsimp.ly/69. Heck place bid on it, It's not official till I accept it. I will send it any way you want, so if you want to pay for next day air you can have it on your desk on Tuesday :)

More views at
http://twitpic.com/1y0x9w
http://twitpic.com/1y0xcl
http://twitpic.com/1y0x4q.


All the parts have been processed, you can see them go together here:

$250 for a set Mendel RP components printed on Makerbot #469

For sell here http://sellsimp.ly/5p This is the same set that was videoed in my series on how to put together a Mendel on youtube here http://www.youtube.com/watch?v=-UFP0lcE4sY

I am glad to see the prices for RP parts are falling, means the community is becoming more healthy, but it hurts when you try to sell :).

Nice Recipe for Machineable Wax

I have been working on the Xerox Mendel for a bit, and I keep running into issues with the wax shrinking too much. I found out that I need to let the Wax cool down slower, which makes it leak out more. I am going to have to find a good balance.

Found this website: http://www.machinablewaxes.com/machinable-wax-recipe/ they have a great description on how to make machinable wax at home. All you basically do is melt LDPE in a deep fat fryer full of paraffin wax. Basically you raise raise 4lb of paraffin wax to 95C for LDPE or 110C for HDPE. You then add 1 lb of LDPE or HDPE very slowly. Any amount can be made. Considering the limitations of a Maker bot drimel toolhead, this could be a great substrait.

The store this is from looks like it's dying, so I will quote it here:

"You may be looking for a cost effective solution for machinable wax.
One basic composition of machinable wax is simply standard parrafin wax, available at most craft stores, and polyethylene.
What is polyethylene? It’s most basic description is that it is a thermoplastic and it is derived from petroleum. The two main types are Low Density and High Density polyethylene, commonly referred to as LDPE and HDPE respectively. The following is a list of common LDPE/HDPE items:
* Grocery store bags
* Garbage Bags
* Paint drops (plastic sheets)
* Lawn Chairs
* Cutting Boards
* Plastic Lumber
* Milk Jugs
* Commercial Bathroom stalls
One of THE most common uses is in plastic grocery store bags. This is also probably the best source of LDPE/HPDE for use in making homemade machinable wax. It’s readily available as most people have 50 or so stuffed away in a pantry or cabinet. Perfect to make a little machinable wax with.
Alternate sources for use in a machinable wax recipe, would be plastic drop clothes used in painting. They can be purchased at most home improvement stores.
Most plastics are usually marked with LDPE or HDPE and have a number 4 or 2 (respectively) located on recyclable polyethylene.
In general it’s easier to melt down LDPE for use in machinable wax. LDPE has a lower melting point, and hence mixes better with the parrafin. LDPE’s melting point for continuous heat is 203F (95C). HDPE’s melting point with continuous heat is 230F(110C). It may be helpful to note that in general Target uses LDPE and Walmart uses HDPE.
What to use for melting??? You everyday kitchen cooker will work fine. It’s HIGHLY recommended that you dedicate a cooker to your machinable wax recipe. Temperature control that lists numbers is better than just lo/med/high. Do not use a double boiler, they generally only get up to 212F(97C). That’s only barely hot enough to melt LDPE, and it would take a lot longer.
So you have your block of candle wax, a few handfulls of grocery store bags, and a cooker. A METAL kitchen strainer will be very helpful as well. The large ones used for pasta noodles are best. You also need a mold to poor your machinable wax into. Use metal molds, plastic tupperware will melt or warp from the heat.
The general machinable wax recipe is a 4:1 ratio of parrafin wax to LDPE/HDPE. Your machinable wax recipe could vary depending on how hard or soft you want the wax to be. Obviously, the more plastic you add the harder it will get. But like sugar in a glass of tea, eventually the polyethylene will stop disolving and you will get large clumps of polyethylene form in the pot. If you poor it in a pan without straining it, it will look like goo in your wax and will not carve very well.
We will use a 4lb wax to 1lb LDPE in this machinable wax recipe example. So you will end up with about 5 lbs of machinable wax.
Start out by melting the wax in the pot. Get it good and hot, about 250-275F, max 275F.
Once you’ve reached temp, start feeding in small pieces of the plastic. If you can, cut up the plastic into small strips before feeding it in. It will melt better and more consistently than just dumping whole bags in. Stir constantly and use good ventilation.
You will know you’ve added enough because the plastic will stop melting as well. It will start balling up into clumps.
Now you can use the kitchen strainer, poor your wax through the strainer into your mold. This will remove any unwanted clumps from the mix.
For cooling, try to slow down the cooling as much as possible. You can wrap the mold with an old blanket, or use a small space heater to keep the area around the mold warm. Some warping is unavoidable. You can either plane the finished product, or use a CNC router to shave down the top.
You will be left with a good quality machinable wax. Refine your machinable wax recipe. You may try different types of wax, or different types of polyethylene in your recipe.
We also offer kits of shaved LDPE and HDPE. Our kits are sold by weight and use LDPE/HDPE shavings that will melt better than most types of plastic you may find."

Trying out Sellsimp.ly for selling RepRap Parts

The CFO of my house has defunded my RepRap hobby. In other words I have to sell my Mendel if I want to finish my 3 other mini Mendels (yes I have a problem).

I read about Sell Simply, which is a VERY simple selling site where you start your listings, and have all your interaction through twitter. Selling is a flat $1. That's it, no commission. All transactions are handled though Paypal.

There's two options with this sell $450 for all the RP parts, or $1500 and I will send the whole RepRap, electronics, motors, RP, rods, belts, and Lasercut parts. I will load it all up in a 1560 Pelican case and send it on.


If your interested go to http://sellsimp.ly/5p