[TC22] Dumper

[Seasider]

So I took a gamble the other day and started on my entry while the completion thread was in discussion. I’ve decided to go with a small Dumper vehicle, the one you’ll see on a building site and not the huge behemoth things you’ll see in a mining facility / quarry. Why have I decided this, we’ll I wanted to build something you’d regularly see in the U.K. and also something I remember playing thinking we’re cool as a kid.

My plan is to build a generic one and not a specific model but thought it was worth starting from a real vehicle to give me some proportions. So of course @Sariel came to the rescue with his scaler.

I’ve started by using the Jeep tyres for scaling (I’m betting a lot of wheeled models will end up in these). This gives me about 27x13x27 roughly (depending upon where the beacon goes and what the tyre position ends up being). So approximately 9,500 cubic studs.

I’ve then played about in stud.io to see what this looks like and here’s the result of an hour.

So the basic dimensions look ok. The challenge will be in getting any functions to fit in the rear structure.

The plan is for direct (not HoG) steering with a central pivot which also allows for pendular suspension between the front and rear “axles”.

The bucket I’m looking to build with system parts (I don’t think that breaks @Jim’s rules as it’ll be mainly Technic for the whole model).

But the biggest challenge will be packaging the pneumatics that I want to get in. At a minimum I need the bucket to tip, ideally I’d like to add bucket lift too, just like the Dumper I’ve used for a guide.

I wanted to do something pneumatic as apart from when we did a pneumatic competition I don’t normally work with them, so wanted the challenge.

 

I’m hoping I may get the odd hour or two to work on this before Tuesday as I’m just about to go away on holiday for a week … thanks for some fantastic timing Jim … only joking I know how hard it is to get these up and running. Otherwise it’ll be a week or so till you see an update from me.

[Jim]

3 minutes ago, Seasider said:

The bucket I’m looking to build with system parts (I don’t think that breaks @Jim’s rules as it’ll be mainly Technic for the whole model).

That is fine!

[Thirdwigg]

Glad to see you in this contest @Seasider. I'll watch closely to see how this come together. Perfect choice for the topic too. 

[Jundis]

At first glance I thought this will use just a normal bucket tilt but at the closer look, it's a boom underneath the bucket, right?

[2GodBDGlory]

This should be cool to see! I don't recall ever seeing this kind of thing built with Technic, which makes it a fair bit cooler.

[Seasider]

Thanks @Thirdwigg I hope you’re entering too

@Jundis the one I’ve used for reference has a boom lift for the whole bucket (the side view shows you the 4 positions for the bucket). I want to try getting both functions in the model but I’m also aware of the space I need for the pneumatic pump and the two switches … plus the steering mechanism.

[Thirdwigg]

1 hour ago, Seasider said:

Thanks @Thirdwigg I hope you’re entering too

I'll get there. I'm trying to make some decision about what to build first.

[Seasider]

So as I hinted I was away on holiday for a week, but I managed to get the odd bit of time to see some of the fantastic WIP threads lots of people have created.

I did also get some time to think about how to solve some of the problems I was seeing. @Akassin’s build showed me a solution to one of my problems as I wasn’t aware of the pneumatic switch with the ports on the bottom and not the side. So I’ve got a couple of those coming to help me.

In my lunch breaks (a benefit from working at home) I’ve managed to play about with the front lift mechanism and I’ve come up with this.

First iteration which then led me to this today …

as you’ll see I’ve switched to physical as I’ve found playing about with connection points and angles is easier. I’ll put it back into Stud.io at some stage.

Hopefully I’ll get an hour or so to have a further play this weekend. Next problem is what does the steering look like. I’d love to have both steering and pendular suspension as per the real vehicle but I need to see how it goes at this scale.

 

 

Edited April 23, 2022 by Seasider

[Akassin]

1 hour ago, Seasider said:

I did also get some time to think about how to solve some of the problems I was seeing. @Akassin’s build showed me a solution to one of my problems as I wasn’t aware of the pneumatic switch with the ports on the bottom and not the side. So I’ve got a couple of those

yes, these new switches from 42128 are very useful.
  Great bucket lift!

[Thirdwigg]

Great solution @Seasider. I look forward to more on this project!

[MangaNOID]

Always wanted to build one of these. This looks promising! I thought the lower small pneumatic valve might not be able to handle the full weight of the tipper but I just pumped one up to see and they are actually pretty good! I might need to use them more!

looking forward to updates.

[Seasider]

15 hours ago, Thirdwigg said:

Great solution @Seasider. I look forward to more on this project!

Thanks, still trying to decide if the bucket will be System or Technic.

Have you started an entry ?

5 hours ago, MangaNOID said:

Always wanted to build one of these. This looks promising! I thought the lower small pneumatic valve might not be able to handle the full weight of the tipper but I just pumped one up to see and they are actually pretty good! I might need to use them more!

looking forward to updates.

Yes it’s surprising what the little pistons can cope with @Sariel has a great video where he reviews all the pistons and gives you load capacity for them all.

 

[Jundis]

Great prototype! Was about to ask the same question, but looks like the little pneumatics can handle the weight. I am curious about your final design :-)

[Seasider]

So a little bit more work from me this weekend, an hour or so on Saturday to work out the steering which resulted in this …

which I was happy with as it gave me both steering and pendular suspension.

Then today I ripped it apart and created this …

Which I think is where the pump will locate.

Then I started building all these in Stud.io to try and work out how to cleanly connect them together, and how to get the switches positioned (thanks @Thirdwigg for the file). But I didn’t get this completed so no images of that today but hopefully during the week.

Also while in a supermarket today I found this … 

I honestly didn’t realise this months Lego City magazine had a Dumper with it … but it’s a bit smaller scale … I was actually looking to see if the magazine with the Space minifigure was available!

 

Next challenge … complete putting my sub-assemblies into Stud.io to work out the rear frame.

[Jundis]

9 minutes ago, Seasider said:

Which I think is where the pump will locate.

Do you think the little pump will provide enough pressue when manually activated?

I would have guessed you use the big pump and place it under the seat (diagonally, from lower front to upper back) and use the seat for pumping action ;-)

[Seasider]

8 minutes ago, Jundis said:

Do you think the little pump will provide enough pressue when manually activated?

I would have guessed you use the big pump and place it under the seat (diagonally, from lower front to upper back) and use the seat for pumping action ;-)

I’m not sure yet. I’ll give it a test this week, if not I like your way of thinking of using the seat and a bigger pump

[Thirdwigg]

On 4/23/2022 at 6:56 AM, Seasider said:

Have you started an entry ?

I got an idea, and rough draft. I'll try to post something by next weekend. I'm a little stacked at the end of an academic term, but I realize I am running out of time for the contest.

I'm glad the file worked well for you. Sorry I didn't have any more to help with.

I am also interested to see how that pump will work. It's a clever idea, so hopefully it will function as intended. 

[Seasider]

So a little update from me. The pump idea was a bit difficult to “break over” the maximum compression of the pump, so I’ve moved the pump so it’s inline with the axis of the crank. I’ve also changed the gear you turn into a crank piece (not sure it’s official name) as you can rotate this easier without it slipping and so losing pressure.

But most of the week my desk has looked like this …

… as you can see lots of playing about with bits. Most importantly a Technic bucket and also a revamp of the part that connects if you the booms. Originally this was a bent liftarm but the bucket didn’t sit flat, switching to a series of connectors has meant the pivot and piston attachments moves and the bucket sits more level (but not perfect).

Also I’ve been doing a lot of mess in this …

… the main bit of this work is how to do all the rear frame assembly. As you can see it’s very much WIP and also I need to update the bucket and front assembly too.

Its a long weekend here in the U.K. so I hope I’ll be able to get some tinkering time and if so I plan to take some of the digital and turn it into real bricks … assuming some BrickLink orders arrive.

 

Edited April 29, 2022 by Seasider

[Seasider]

Tiny update from me. Spent a lot of the weekend out and about and the BrickLink orders didn’t arrive till today. This was my progress I’ve the weekend in stud.io

it looks about right but a lot of the rear end may have some very dodgy connections. For me I now need to build this in physical bricks to see how it all hangs together and where it flexes. It may not be until the weekend that I’ll get round to doing this though.

[1980SomethingSpaceGuy]

Very nice model! Love it.

[Seasider]

So a little update from me of this weeks activity.

First task was testing the pneumatics so in good engineering fashion I tested each bit one by one using this monstrosity

Here are the tests I did …

1. pump to one switch and one piston on boom lift no bucket

2. As 1 but both boom lift pistons

3. As 2 but with bucket added

4. Pump to bucket tilt with bucket

5. Pump to both switches boom lift test no bucket

6. Pump to both switches bucket tilt test no bucket

7. As 5 but with bucket

8. As 6 but with bucket

… and they all worked !

So now I know the pneumatics worked I thought I’d finish converting the stud.io file into the real thing.

and this it the result.

I’m happy with how it looks, but there’s now the fun challenge of routing all the hoses I need! I’ve absolutely no idea where I’m going to route them yet.

Also I’ve found that although the rear tyres spin freely when the model is off the ground I’m obviously getting some sag in the axles/tyres which means they rub badly against the lift arms above them. Which is bad as I like the look of the “arch”/“protection” over the top of the wheels.

But my biggest challenge for completion is time! I found out last night that not only am I away next weekend (planned for a long time) but I’m also away the last weekend in May as it’s my birthday. So perhaps my journey in this competition will come to an end a bit prematurely for me.

Hopefully I’ll start doing to tubing this weekend.

Any thoughts about if I should leave the liftarms above the wheels as they are ?

[1980SomethingSpaceGuy]

I would pimp those arches indeed.. Not only do they look too close to the wheels, but if they actually rub, this needs fixing. Maybe another pair of those L-shaped panels? 

Good luck with that and the routing of tubes ! Hope you'll find the time, would be a shame not to have you in. 

[Seasider]

@1980SomethingSpaceGuy I took your advice and redid the arches, which means I redid 80% of the rear frame. Means the wheels roll smoother and gives it a more open look but I think it works. Fingers crossed I can do some tubes tomorrow.

 

[1980SomethingSpaceGuy]

Looks nicer too! Good job! 

[Thirdwigg]

I hate it when you find out after a good idea that the tires rub! I’m glad you were able to make a change. It looks great. Now hopefully all the hoses will fit.