Advice needed on 42009 to GMK6400 upgrade

[dognosh]

I now have about a dozen sets under my belt including one minor mod of a Lego set.

I would like to build the GMK6400 (MOC 5509) , http://rebrickable.c...00-mobile-crane , but not with the Firgelli Actuators, but with the modded lego linear actuator boom , http://rebrickable.c...00-mobile-crane .

I have downloaded the GMK6400 ver. 1.2 Instructions, and the Linear Actuator PDF too. I have most of the parts(including a 42009) and the rest will be here in a few days.

My question : I read both the 6400 instructions and the Actuator instructions. Would you fully build the 6400 , then modify the boom ?

Or run both instructions at the same time, swapping between them as needed ?

(I could build the 6400 without the firegelli then mod it, but am thinking of modding as i go along)

ty :)

p.s. Can anyone link me to a decent boom string, as I don't even know what to search for or the thickness that is best ? It needs to be about 5m, ty

Edited September 13, 2016 by dognosh

[Imanol BB]

Hi, i think that the best option (or at least what i would do) would be the second one, but only if you make sure that everything works right, that way you could get the linear actuator and the boom to have a better look balance between them, about the string, some designers use fishing lines and nylon strings, bur this lines can also wear and cut your pulleys if they are under high pressure and movement for long times, to solve this, i mostly use multi-filament nylon lines, is almost the same material and strength, but because it has multiple filaments instead of one, the pressure has more distribution an so, the wear and cutting is reduced, and the pulleys last longer.

[dognosh]

Hi, i think that the best option (or at least what i would do) would be the second one, but only if you make sure that everything works right, that way you could get the linear actuator and the boom to have a better look balance between them, about the string, some designers use fishing lines and nylon strings, bur this lines can also wear and cut your pulleys if they are under high pressure and movement for long times, to solve this, i mostly use multi-filament nylon lines, is almost the same material and strength, but because it has multiple filaments instead of one, the pressure has more distribution an so, the wear and cutting is reduced, and the pulleys last longer.

I am looking at a 1.2mm string(my crawler set,42042) and it looks good. Of course the 42042 isn't 5M, shall search the net.

TY for your reply :)

[motomatt]

My question : I read both the 6400 instructions and the Actuator instructions. Would you fully build the 6400 , then modify the boom ?

Or run both instructions at the same time, swapping between them as needed ?

(I could build the 6400 without the firegelli then mod it, but am thinking of modding as i go along)

ty :)

p.s. Can anyone link me to a decent boom string, as I don't even know what to search for or the thickness that is best ? It needs to be about 5m, ty

I think its easier to read the modifications and just modify the instructions as you build, since the modification here is pretty simple. What I did was

1. Build the 2nd version of the Carrier from Grove6400-MKIII_1.1-test.compressed.pdf. These instructions are for the carrier without shock absorbers and the superstructure with firgelli actuators. (You could probably build the first version of the carrier if you liked.)

2. Build the boom from the same instructions. Just make sure you modify the boom attachment point as documented in the instructions for the actuator made out of lego.

3. Build the actuator made ouf of lego.

4. Build the superstructure from the same instructions making sure to make the modification documented in the instructions for the actuator made out of lego.

A string like this one works good for me https://www.amazon.com/gp/product/B001G2PESY/ref=oh_aui_detailpage_o06_s00?ie=UTF8&psc=1

[afol1969]

Hi dognosh,

I've read the thread with the modded technic actuator (which is an excellent solution ), but didn't have the time to build the model with this actuator. In future time I plan to implant the actuator instructions in my own instructions, and even to test it with efferman's boom.

I think too you should follow the suggestion from motomatt.

An improved version of the actuator instructions you'll find here: http://www.bricksafe.com/files/afol1969/Instructions/actuator.pdf

Greetings

Alex

[dognosh]

Motomatt, thanks a bunch :)

afol1969, and you too :)

I came to forums because I was mistakenly using the 1.2 files and I found I needed 14 shocks I didn't have So I looked at the 1.1 and worked it out. But I still came here to check !

Thanks both of you, I have examined all 3 files,so :

1. Build using Grove6400-MKIII_1.1-test.compressed.pdf

2. use afol1969's link to build actuator (http://www.bricksafe.com/files/afol1969/Instructions/actuator.pdf)

3. go to page 16 in GMK6400_linear_actuator.pdf and continue from there

4. Build RC unit either from afol1969's bricksafe, or my own design :)

A string like this one works good for me https://www.amazon.c...0?ie=UTF8&psc=1

I already ordered one, but it is 1.2mm(like in Crawler set) , lets see if it is suitable and if not I go for yours.

[dognosh]

Wow ! I am loving making this

I have nearly finished the platform/cab/running gear/electrics/outriggers. Soon to start on the superstructure and boom, built the lego actuator :)

To those who helped in this MOC design, wow you guys are stars !!!

To the Instruction maker, superb job.

Back to work !

[dognosh]

All done! Ok, i lie, nearly all done. One question.

I have all 3 sections of the boom, and can see the mechanism by which the middle boom extends.

How does the inner boom extend? For the life of me I can't remember how the original 42009 did it!

Edit: I see it is in the cabling

Edited September 20, 2016 by dognosh

[dognosh]

All done ! :) Thanks to the designers & Instruction manual makers, this is a fab MOC !

I modded it slightly, added rear lights, added lights to the 2 orange lights on top of cab, covered engine bay, made rear box(totally covered) for counterweight & beefed up lego actuator as it would skip teeth when horizontal.

[DTom]

1 hour ago, dognosh said:

All done ! :) Thanks to the designers & Instruction manual makers, this is a fab MOC !

I modded it slightly, added rear lights, added lights to the 2 orange lights on top of cab, covered engine bay, made rear box(totally covered) for counterweight & beefed up lego actuator as it would skip teeth when horizontal.

Pictures !!! ;)

 

[dognosh]

On 10/4/2016 at 11:55 AM, DTom said:

Pictures !!! ;)

 

Sorry, only just saw this :)

You guys are all brilliant, thanks for all the help !!!!!!