Antweight Kit

[Merkabah_PT]

Thank you Phil! I had searched for a shipping table before but with no sucesse.
200g is more than enough for 3 servos.

2x Tower Pro MG90s
1x Tower Pro MG16R
32€ with shipping from Portuguese site, in 24h i have my order at home.

2x Turnigy MG90s
1x Turnigy TGY-9018MG
17€ with shipping from HobbyKing, Hong Kong

Almost half the price!

The Tower Pro and the Turnigy MG90s are the same servos but rebranded right?
How much does it take +/- for the parts to arrive?
Problems with customs?

[Phil]

No worries. The shipping table is took me a long time to find also.

I have used Turnigy servos with good success in the past. Now, I mainly use Corona. They are cheap and reliable.

My last HK order took 19 days to Australia. (It arrived last week.) That was during Chinese New Year. Never any problems with customs for me.

Have you considered working in with Marto and Aaron of BotBitz using their new kits? They are good guys.

I hope you are successful with your endeavours.

[Merkabah_PT]

I've been following the Australian Robot Wars forum for some time, but i am not registered.

To speak the truth, their robot kits inspired me to try to do something here, as a company called weproductise is going to open this month near my city and their goal is to help people make their project come true (they have laser cutters, 3d printers, cnc's and people with master degrees in engineering, design and marketing to help). Link for their site:http://www.weproductise.com/

Marto and Aaron sure do A LOT for this hobby from what i see. It would be a previlege to be able to work with them bringing their kits into Portugal. But i think that's dreaming to much, and besides, their kit is too much for what i had in mind.

For now i just want to develop a ant as cheap as possible and build two of them so can get people to try them. Then, if some people were interested, i could make a couple of kits and sell them.

The second part of the project will be very difficult, as the robotics/electronics community here are alergic to combat and remote controlled robots....

If i could get like 10 people into to this hobby and host a small tournament it would be a dream come true!

Thanks for the support!

[duff]

If we're talking good, cheap drive servos, can I make a recommendation? The hobbyking hk15148 are cheap, not too small and have lots of torque. They can also be easily speed hacked. I've found a lot of the smaller 9g servos lack torque when they have been speed hacked. Plus the gears are bigger, so they're harder to strip. Also, most Lego wheels will fit straight onto the output shaft.

http://www.hobbyking.com/hobbyking/stor ... 0_14s.html

I used them in my first cluster, Warhorses, and they worked great. The drive servos, weapon servo, battery and receiver only cost me about £10 in each robot. The main cost was the 3d printing.

... ata_player

[Merkabah_PT]

Thanks for the recommendation, but i will stick with the metal geared servos, they will last much longer.

How much did you pay for one of those 3d printed chassis?

BTW, i found this russian site with instructions to mod the MG90s to 360º rotation: http://robocraft.ru/blog/mechanics/595.html
But using the Chrome translation, the instructions are rather confusing. Anyone has a tutorial in english or just step by step photos?

[daliad100]

MG90s 360 mod Bottom of this thread

Use stiff glue (epoxy or super glue) so the neutral position won't drift or swap the potentiometer for 2x 2.2k resistors.

[Merkabah_PT]

Thanks for the tutorial Jordan.
Does the main shat wooble with this method? The guy in the russian tutorial only cuts the rotation stop of the plastic piece, insted of fully removing it. He also bends the pot limiters for it to be able to fully rotate.
I might go with a mix of the two methods, but i will analyze that better when i get my servos.

Just found a cad of TGY-9018MG, the mg90s is exacly the same size and shape, so this cad will work for both. Just need to do myself the reciever and the battery pack.

[Merkabah_PT]

So, this is a chassis i did today on SolidWorks. It's about 140x120x45mm.
I have tried some websites that say how much the printing will cost, and they say around 80€ and 170€.
A LOT of money for such a small and simple chassis.

Can someone that have used 3d printer/3d printing services tell me if the price is right?

I will only know prices of the company near my city in the end of the week, but i bet it will be more expensive than company in other countries...

If this prices are right, making the robot out of carbon fiber is much cheaper...

(I can send the SLT file if someone requires it to calculate prices.)

[harry hills]

tried shapeways?

[Merkabah_PT]

Yes i did.
Around 80€...

I used 4mm thick walls, maybe thats to much? I've never seen or grab any 3d printed parts... Maybe 3mm is enough?

I will make a version of my chassis with 3mm walls and try the cost simulator again.

Edit: Changed to 2.5mm outter walls and 2mm for the battery box, 45€ with wheel covers, 43€ without them. I will try and make some vents on the chassis in hope to reduce the cost even further.

Does someone knows if 2.5mm wall is to fagile? This chassis is not for competition, just to try to make kits for kids and teens to get in to this hobby, only play fights against other identical robots.