Tashic's Robots

[RogueTwoRobots]

Onyx's shaft is 12mm silver steel and it has gradually bent over time. Not to the point of making the axe inoperable, but enough to make it a pain to take apart/get back together. We're talking about a 1 year period and a lot of axe hits though, so it's not an instant problem, but I'd say 15mm would be a more comfortable size.

[maddox10]

Hatchet axe has a 20mm shaft , and the handle double layer steel tube with the bigger tube 1" heavy gauge steampipe.

[mrsam]

I agree with people's comments about the shaft I'd definitely increase the diameter just to be safe, Hatchet's is just as Mario said and is really strong and really well made but it's overkill for overkills sake.

Depending on how powerful your axe is you may have issues with the 6mm chain snapping like I did last year, the 8mm stuff is much stronger and handles the new Hatchet's set up no problem despite it being much more powerful, may be a worthwhile upgrade to be on the safe side.

Robot looks great though I can't wait to see it going, are you planning on coming to any UK events with it?

[Tashic]

Thanks, shouldn't be difficult to upgrade the shaft.

And yes I plan to bring it someday to the UK, Sam.

[Tashic]

More progress:

Progress has been very slow, because school manages to be stressful even if we don't do anything most of the time:
IMG_3508.JPG
The axe head is (of course) not final, it's just a piece of HDPE that looked like an axe after I made the parts.
IMG_3511.jpg
The bulkheads and the motor are fixed to the base, today I made the front pannel.

Also a question, what you use to cut HDPE?
I used a rubbish, el cheapo jigsaw, that has a very wobbly blade, so I made some modifications that made a very small difference.
This is the cut on the front plate:
IMG_3514.JPG
It was actually worse than this, the blade tended to turn to the right.

[maddox10]

I use different means to cut it. Jigsaw, disk saw, even an anglegrinder (melts the stuff, not clean nor good to welded it.)

[mrsam]

I've used an angle grinder to cut to cut it before, works okay but it does tend to melt it a little bit and it's really messy. Personally i use a chop saw with a wood ripping blade, nice clean, accurate cuts but if that's not within your means a grinder will work fine.

Also just a thought, you might want to shorten the axe shaft quite a bit, it's make it less likely to bend and you'll get a faster weapon because your axe head will be closer to the pivot point.

[Tashic]

A bit more progress:

The front HDPE pannel is bolted to the supports and the base, and I fitted the chain and did a selfrighting test:

https://www.youtube.com/watch?v=_UfS7IHn-10

Also did a test on a small metal container, and this is the result:

IMG_3534.JPGIMG_3535.JPG

Will see how it will perform with an axe head.

And yes, I will shorten the axe.

[Tashic]

Small update:

front and back has been cut and bolted:
IMG_3711.JPGIMG_3712.JPGIMG_3713.JPG

Now for the sides and then start with the steel! (And very likely weight shaving)

[mrsam]

That looks awesome man, sort of got a whiff of Hatchet about it but 4wd and sleeker. It's actually eerily similar to how the new Hatchet was going to be, can't wait to see it going.

[Tashic]

Little drive test:
https://www.youtube.com/watch?v=npOWzjtGlWA

Servos and microswitches with 2 12 cell NiCd packs, one for each side.

[Tashic]

Continued the build, by adding front and side armour:

I still need to add bolts.

Now the problem is that at this stage I'm 1kg short of the weight limit, and I still need a top cover and electronics.
So when you fing that your robot is overweight, or is going to be over weight, what do you do?
Also how people make their drill motor mounts and how much they weight?

[Tashic]

Moar progress, about time...



Other than the obvious top cover (10mm HDPE), I replaced the base with 3mm aluminium, and the mounts are now 10mm HDPE too, so now I have 2Kg for the electronics and battery, plus other things to remove for the axe, but that's for later.

Tz85's from hobbyking, and I'm thinking of a 5s 4000mAh lipo battery, 4s is probably not enough to self right.
I'll then need to build a box for said battery and ESCs.

As the motors are rated only for 12V, can I just reduce the travel on my TX to save them?

[harry hills]

You're a really talented builder. That's fucking ace!

[overkill]

You can definitely rate limit your radio to reduce motor heating but with 12V motors running on 14.8V, its probably not necessary. A 4AH battery seems way too large for a non-spinner; it doesn't hurt to have extra capacity but you can save weight & money with a smaller pack. Without knowing much about your bot, I'd guess a 2.5AH pack is probably enough.