New Heavyweight

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Remote-Controlled Dave
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New Heavyweight

Post by Remote-Controlled Dave »

Right, time for an official announcement I think. Me and Marco are building a new Heavyweight, with a little help from Dave Weston too. Gunna use this section for another build diary, similar to the one we did for Monolith. Not a lot to report yet, more news when it happens.
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Marco Roberts
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Post by Marco Roberts »

I guess its time for the first entry.
I do quite like doing these build diarys. Even if no one reads them I do like looking back at them for some kind of reflection :)
Its coming up to nearly two years since we built Monolith. It was a great experience and was probably the most reliable thing I built outside of 150 grams.
Now two years later I have become better at it. I remember a personal rule that anything you rush always ends up bad. Monolith was a nice slow build with no rushing and it did well and did what we expected. Any feather weight or ant weight I build in a hurry always has issues.

My and Daves key goals with Monolith was to build a heavyweight which could fight in a heavyweight competition with no experience in heavyweights and as cheaply as possible. Not cheap as in:

"Ohh I had these bosch 750's lying around with spare batteries and weapons and all I needed to buy was a couple of washers."

We started with nothing. All I had was a corded drill. Monolith came to around 300 pounds the most. Including radio gear.

Now our goals with this new heavyweight is similar. A cheap robot using only the existing motors. But built to last. We will give into the peer pressure and make it out of proper materials but built it in a way that is simple and any novice can do it.

The new heavyweight will be made out of 4 20mm HDPE bulk heads. Bolted to this will be lots of 3mm steel angle.
The armor will be bolted onto the angle and we are aiming for just really thick steel. It was going to be hardox but I released I needed the sheet and it will need loads of holes drilled into it and I hate drilling hardox.

Weapon will be interchangeable. First weapon will be a saint hammer/ stinger kind of weapon. We are also planning for tanto/anto clone prongs. A linear actuator lifter and a electric crusher.

Electronics will be my wotty for now. We might replace it for something else. 2x 18 amp SLA batteries for now. We plan to upgrade to 36volts one day when we get another charger and have the wotty upgraded.

First build diary entry will follow shortly. Best get back to work as a render just finished.

Regards
<-=AWS 10 1st and 2nd champ=->
<-=AWS 13 1st and 2nd champ=->

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Marco Roberts
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Post by Marco Roberts »

Beginnings 7/12/08

I made an order for the HDPE and it all arrived on the 5th. I had never seen such thick HDPE. 1meter by .5M and 20mm thick. Did not have any flex in it at all but hopefully should be suitable for the bulkheads.

Image

I decided to make a start cutting the peice up. I decided that the main body of the robot should be 500mm long and 200mm tall. I wanted the robot to be as small as possible as well.

At this point I realized that my cheap table saw was not big enough so I would have to do it by hand with the jigsaw. The jigsaw is ancient and I bought it before the turn of the century! No variable speed and could not setup a guide as the base was crooked. I have gotten used to it though and I made some lovely strait cuts by eye!
At this point I realized how much of a pain it is to cut 20mm HDPE. It did cut, it just took an age. By the last one I was a bit tired but still happy with the results. I tidied it up on the metre saw and cut in the little bevels that are on the back of the design. Just to break up the shape from a massive cube.

I lined everything up and quite happy with how its all looking.

Image

All that I am waiting for it Dave Weston to get the steel angle but next I will start on attaching the motors to the outer bulkheads. This is an important job as I believe it will be the most likely to fail. Still deciding how I can do it but it should be solid enough..

Still early days and have not done much but hope to continue building after work on Tuesday.
<-=AWS 10 1st and 2nd champ=->
<-=AWS 13 1st and 2nd champ=->

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Simon Windisch
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Post by Simon Windisch »

Hi Marco,

Your build diaries are always a worthwhile read.

Simon

Remote-Controlled Dave
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Post by Remote-Controlled Dave »

Its going to be an interesting build. The three team members are so far apart that all coming together at the same time is a bit complicated. I no longer live on Marco's doorstep which is a shame, but we'll get it fighting early in the new year I reakon.
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Marco Roberts
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Post by Marco Roberts »

10/12/08 Footnote

No actual building. The bulkheads have been sitting in my room and occasionally I like to prop them up again and admire how this thing could look.

Was going to build yesterday but found out that my local cinema charges 7 pound to see a film. Aside from Tuesdays where its four pounds. Needed to see Madagascar 2 to admire the animation.

The main part which was going to help me attach the motors to the bulkheads was m8 steel rods. They were cheap on technobots at less then a pound each. However I have just been told they are on backorder :(
Last time I had something on backorder from technobots it arrived 2 months later!
I did also need these for my newest feather but I will worry about it later.
I will make a few side trips today then. Needed to get a new battery for my calipers and also get a part of my bike. I will just make another side trip to wicks and see if they have anything similar to threaded rod. Maybe large roofing bolts of something. Even though these wont take much strain I wont settle for anything under m8.

Hopefully if I get what I need, these motors will be mounted tonight.
<-=AWS 10 1st and 2nd champ=->
<-=AWS 13 1st and 2nd champ=->

Remote-Controlled Dave
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Post by Remote-Controlled Dave »

You mounting the motors Marc? I thought you were doing that when one of us was there? Ah well, go ahead if you reakon you can.
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Marco Roberts
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Post by Marco Roberts »

I managed to mount side no problem Dave. Didnt really need a hand with this job as it was just time consuming and fiddly.
There are jobs which will require more hands.
Battery mounts, a quick mount so I can take the wotty out easily. Still need to use it in my feather for a few fights.
The most time consuming job will be fitting the armour. Drilling around two dozen holes into each plate then drilling holes though that plate into the angle then drilling holes into the other side of the angle then bolting it all together......yeah that will require help.
Will post official build diary later. Left my camera here at work and I want to make this build diary quite visual.
<-=AWS 10 1st and 2nd champ=->
<-=AWS 13 1st and 2nd champ=->

Remote-Controlled Dave
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Post by Remote-Controlled Dave »

I could always take it round mine and do all the armour fitting Marco if you want. After the 20th I'll have plently of free time. I'd rather I did some of the work than just wait for you to do it all.
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Marco Roberts
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Post by Marco Roberts »

12/12/08 - Motors mounted

After a lot of fiddling around both motor mounts are now attached to the side bulkheads.

Image

They seem quite secure. I managed to get some m8 threaded rod from wicks for around the same price as technobots. I also used some nylon lock nuts to attach it all together. This is to reduce the chance of them coming undone.
Bridged across is 3 layers of 1mm steel stuff. I got it ages ago for an old feather weight. If it doesnt hold I will replace it with some thicker steel.

Image

I like how they curve with the motor for a bit more support. The main idea behind the mount is that there is one bolt at the top which fixes it basically in place. Then four bolts above and below the motor to support the motor. It should be strong enough.

My new worry is mounting the wheels. The wheels attach ok but because the nylon is quite thick for the shaft the wheel would rest against the nylon and rub against it. I made this bracket to push it out by around 8mm. The wheels now fit quite flush to the side but dont actually touch it.

Image
Image

The only thing that stops this wheel from sliding off is a m6 bolt. Even though these wheels are flush and barely wiggle I can imagined a bad flip and off flies a wheel. Also noting that these wheels weigh around 5kg each. So they arnt light. However the wheels are quite keyed into the motor shaft.
Image
Over the weekend I will try a stress test by literally hitting the bulkhead against the floor trying to shear the bolt as best as I can.

Nothing left for me to do till I get the steel angle. That will be quite a long job but again not much to do till the armour arrives and I might leave that to Dave L.

Calculated the current weight

each bulkhead with motor and wheel weighs 13.5kg x2
Bulkhead without anything 2kg x2
batteries 6kg x2
wotty 1kg

44kg

Thats half the weight left on armor and weapons. There was talk about a middle weight version but it would be hard. I was mainly worries about being too light to compete but I think will reach 80kg at least.

I guess thats it for about a week. Will post when more work is done.
<-=AWS 10 1st and 2nd champ=->
<-=AWS 13 1st and 2nd champ=->

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