Team Expat - Beetleweight Adventures

[Ellis]

Watercut. The CAD design was sent to a watercutting company, and they cut it out of material they stock. The design has slots between the bore and the gaps between the spokes, to make for fewer individual "windows", as I believe the number of blow-throughs the waterjet has to make has an effect on price. Mario has welded the slots up for me, which is what's visible on the pic.

[Liftoff]

The design has slots between the bore and the gaps between the spokes, to make for fewer individual "windows", as I believe the number of blow-throughs the waterjet has to make has an effect on price.

Why would they charge extra for that?! You mean there's a fee for every time the machine starts and ends a cut?
If so, I consider myself lucky to have found a reasonable shop where they just charge by the length of cut only as I had in the range of 100 separate cuts performed on my waterjet job I had!

Looking good tho, going to be one hell of a beetle weight!

[maddox10]

The blowtrough takes more time than plain cutting, so it isn't abnormal that they charge for every started hole. Also , especialy for waterjet cutting, evey startup has a marked wear and tear on the nozzle. Again logical it costs a bit extra.
Of course, some firms will use a flat fee and add the avarage hole-cost to that making intrate designs a tad cheaper, but simple ones a tad more expensive.
So in my case the firm I work with atm uses the blowtrough cost, and that can be avoided by clever design.
And yes, there are firms a tad cheaper. But this one is only 15 minutes drive away, and they don't complain about small jobs. Even better, they have cut offs at hand in most consievable materials. Send the dxf, specify material, get the pricetag. Confirm order and 4-5working days later the stuff is ready.

[Liftoff]

Granted mario, its all wear and tear on their machinery, the shop I use machine most spares they need inhouse, so that could contribute to the way they charge.

[Ellis]

New stuff has turned up!



Parts are:
1x pack of assorted heatshrink.
1x 1300mah 35c 3s LiPo.
2x 20mm diameter neodymium magnets, 2.2kg pull.
3x m4 taps, slightly different shapes for different tasks.
3m of red and 3m of black 20 gauge silicon wire.
1x set of different cobalt drill bits.
1x 3.3mm drill bit (for tapping).

Well this morning was rather Christmassy!

Also, I'm organising a website. Once I've got some content on it I'll link it, and I may decide to post detailed updates on there rather than here. It'd also contain write-ups on anything we do, for example we're currently building a new workshop space ahead of T3.

[Danjr1]

Hey,
Sweet build you've got there! Noticed that your using the same motors as me but mine havent arrived yet so are holding up my design. The eBay description says 52mm long, 25mm diameter with a 4mm shaft and was hoping you could do me a small favour and confirm that the 52mm dimension is the length excluding the shaft and shoulder.

Cheers!

Dan

[Ellis]

Hiya,

The motor has a little bearing support type thing on the back of it. You can see what I mean in this pic, it's the circular extrusion around the motor shaft: http://image.dhgate.com/albu_3819855...-600rpm-dc.jpg

Including that, but not including the brass-looking shoulder that supports the shaft on the gearbox, the whole unit is 51mm long. Not including that rear extrusion bit nor the brass shoulder at the front, it's 49.5mm long. Including both the front brass shoulder and the bit at the back it's 53.5mm long.

I'm guessing they called it 52mm as that's roughly the medium. The only 52mm long measurement is including the shoulder, but excluding the motor extrusion whatsit at the back. Hope that helps.

It might be worth noting that the gearbox is almost perfectly 25mm in dia (perhaps a fraction under), the motor itself is more like 24mm.

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Beetleweight might be going under major changes design-wise. I have to ask if the current design, with a wedge, is going to be more effective than the seemingly more popular ground-scraping wedgless design most verticals have. If I go for the wedgeless approach, 4WD seems a bit pointless/looks daft no matter how I configure it. We'll see.

Also, I have started a website. I have quite a lot to write yet, to catch up on what we've done, but the whole of Tormenta 1 is written up. Over 5000 words. If you're interested, have a read! www.teamexpat.co.uk

[plargen]

im using the same motor lol

[Danjr1]

That's a big help! Cheers dude!

[RogueTwoRobots]

Nice job with the website Ellis. As someone who regularly posts thoroughly long masses of text, I approve of the content
Will stick a link to it on the RTR website in the next couple of days.

[Ellis]

@Dan: no problem!

@Jamie: thank you! I'll return the favour once I have the "other people" page setup.

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The CAD is a bit messy but perhaps something like this makes more sense:



Either way I have to decide pretty pronto, this has to be ready in 3 week's time, gah!

[razerdave]

It's DBA crossed with Kajuscha !

3 weeks? Is Deeside that close? Or are you taking like a week to travel?

[Ellis]

We don't be doing another big roboty trip this year. We can't fund it. My dad and I will fly over in time for the second and third weekends of next month, as he has to be in place for my grandparents in that particular window. I'm tagging along to get to see some of you and to be able to fight this beetle as Deeside. It's pure chance that there was an event at a suitable time for us to drop in.

Result is, yeah, we have to leave more than a week early!

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I just checked the "workshop" and we have loads of 10mm HDPE left. I was going to get some 10mm nylon for the beetle, purely because it should hold a thread better. If I use the HDPE I could potentially save 50 quid, as postage is a major B. For those who have worked on this scale, how does HDPE hold a thread? I intended to use m4 bolts for everything, what do people think?

If I go for the HDPE I can start building more than a week sooner, I'm just worried it'll come apart easily in battle.

[leorcc]

Dont thread hdpe itself, specially M4 or smaller thread is just too fine and rip right out. Self tapping wood screws would be better.

[Liftoff]

Use plastic inserts for m4 screws, those should fit in the 10mm thickness you have...I wouldn't bother trying to puy a thread on to the hdpe itself tho