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Geschrieben von caterpilar am 24.05.2012 um 12:06:

  CAT 320D excavator

I have started last week with the drawings for my new excavator. I am still working on the plans for the boom and the arm. All plans are based on the 1/16 scale model from Bruder. I am intending to make everything out of metal, except the cabine.
I made two versions of the bucket.
The standard Bruder one


and one which has a quick coupler


the undercarriage design is almost complete. I am waiting from my CTI parts to arrive so I can make sure that all motors fit into it.


I hope that all my CTI parts will come soon, so I can get all the parts created. I can't wait to put the prototype together. I might need to order several sets to bring the cutting cost down (hope to get a quote of the cutting this week)

will update you on the progress

Grussen
Koen

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Geschrieben von Marcel2612 am 24.05.2012 um 12:33:

 

Nice project.

So you want to use these CTI-motors? >CLICK<

I'm not sure if these motors are strong enough for an excavator made of metal.

Usually, the RB35 motors from Conrad or Servonaut are used in those excavators.

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Geschrieben von caterpilar am 24.05.2012 um 12:42:

 

Zitat:

Original von Marcel2612 Nice project. So you want to use these CTI-motors? >CLICK< I'm not sure if these motors are strong enough for an excavator made of metal. Usually, the RB35 motors from Conrad or Servonaut are used in those excavators.

Thanks for the warning Marcel. I might keep the CTI motors for my bruder model and put the RB35 in the metal version.

I wonder if the CTI zylnders would be strong enough otherwise I will have to go to hydraulics. I prefer to have an oil free excavator

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Geschrieben von caterpilar am 24.05.2012 um 15:11:

 

I looked at the dimensions for the RB35 and realize that it is going to be very difficult to use them in an estethic way. only possibility is to mount that on the same axe as the sprocket wheel meaning that both RB35s will run back to back.

so I found these instead
http://www.conrad.be/ce/nl/product/234350/12V-Aandrijvingsmotor-metaal-1231
which are much smaller and could go easily in the undercarriage as follows



i could then run a chain to drive the sprockets

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Geschrieben von caterpilar am 19.06.2012 um 12:22:

 

I finally completed the drawings for the cat 320. I have sent the cad files off to get the parts cut by the water jet. All parts will be made out of aluminum.
The parts kit I created contains:
- 4 buckets in different sizes
- undercarriage (excl. chains)
- cabin and body of the excavator
- baseplate for boom
- boom
- arm

if you are interested in the kit, let me know. if i have several people who want the kit, I should get a better price for the kits.

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Geschrieben von caterpilar am 05.09.2012 um 10:29:

 

Holiday season is over! so I will make some time available to continue my project. Yesterday I received all my Aluminium parts.

Total weigth of the parts is 4.5Kg and all together 482 pieces.

I still need to clean up the parts with some sanding paper to remove traces from the laser cutting.



I have 3 sizes of buckets that will come with the kit



I added a few CAT logo's. That is always nice to create the final touch



Once I complete the sanding I will start putting some pictures and explain step by step the building process.

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Geschrieben von caterpilar am 06.09.2012 um 18:32:

 

day 2.
I started to built the boom and the arm and the body/cabin of the excavator. I started by preparing a few 4mm rods with a length of 50mm to hold the boom and arm parts together until all pieces are fitted. I still need to put the 2 mm screws in.

I sorted all the parts needed for the arm










and finally the side plates to complete the arm.





For the boom it went just as easy. I put everything temporary together for now. I will still need to buy the screws.



Four units in the middle and then the 2 cylinder attachment plates added







that is how the arm looks when completed (without the screws)


and the arm and boom fitted together





I wanted to do only the boom and the arm today but when they were completed I couldn't resist to start working on the cabin and got quiet a parts fitted together



I have created an inlay to help with the fixation for all the body parts.

Here a picture with the 2 inlays mounted












I still have quiet a way to go to add all the backparts for the body








I use a 2 mm threaded rod to assemble and fix all the backplates. Its pretty easy and very ridged.




the body is starting to take shape



so far everything is still put together temporary. I have used some tape to recover my clamps as I will need them later in the built.


and this is the end result of todays work !!



I won't be able to do any more work until next week. I have a busy weekend coming up. I promise that I will continue next week and post some more pictures.

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Geschrieben von ari am 06.09.2012 um 21:18:

 

Looks great!

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Geschrieben von JensR am 06.09.2012 um 21:34:

 

Great job!

> I use a 2 mm threaded rod to assemble and fix all the backplates. Its pretty easy and very ridged.

I think you mean "rigid"?

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Geschrieben von caterpilar am 07.09.2012 um 09:34:

 

I am getting a lot of private messages asking for a copy of the drawings. I am not planning to sell any of the drawings. I spent months creating them and will not sell them. So please do not PM me asking for the drawings. If you want me to cut the parts for you, that's a different thing and I am willing to look into that.

Here is how the body looks with all the counter weight plates in place.


I also cut out a few logo's to add on the body and boom





the body is nearly finished. I still need to cut out he baseplate and parts to hold the boom.





For the 360 degree swing, I have made two round plates which I will mount a slip ring on with a motor and gear.



Next on the agenda will the the undercarriage

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Geschrieben von caterpilar am 10.09.2012 um 20:59:

 

day 4
I started putting together the undercarriage.



No welding or no glue. base, top and side plates connect with the interlocking system. if you desire to, you can still weld it or apply glue.



I am going to install two small motors in the main compartment of the undercarriage. These motors will then drive a chain that runs in the chain compartment as in the picture below.







another closeup of the chain compartment


On each side I have foreseen 3 plates to mount the top track guidance rollers



I also cut a cover for the chain compartment




thats how the Kettenbagger looks so far

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Geschrieben von caterpilar am 11.09.2012 um 15:51:

 

day 5













en the sprocket

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Geschrieben von caterpilar am 12.09.2012 um 10:02:

 

day 6

works continue on the undercarriage


preparing all the steps for the track's main guide wheel

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Geschrieben von wimo am 13.09.2012 um 02:00:

 

wow.

Sorry, but my english is not so good, i`ve learnt a little bit in scool 40 years ago.
Verry nice work, all in sandwitch form constructet parts.
I think its a dificult work all this parts bring to paper.
Thats perfekt work on a upper level.
i can understand that you not give it to any other for copy.
its a hard thing to construct it any moth.
Its a real great work.

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Geschrieben von caterpilar am 13.09.2012 um 10:01:

 

vielen dank Wimo. Your english is great! You can write in German if you want. I do understand German very well.

I have difficulties in writing in German

Many thanks for the nice comments!

Grussen
Koen

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Geschrieben von caterpilar am 17.09.2012 um 11:12:

 

Hier alle Teilen für die 4 Löffeln

Below all the parts for the 4 buckets



I spent a few days thinking how to bend the bucket shape to allow a nice fit with the laser cute sides.
I did not wanted to apply heat to bend the aluminum plates. I also didn't wanted to use a hammer. So I made a very handy tool out of some scrap material I had in my workshop. And it did the job very well.

I did a test bend first with some 1,5mm aluminum first before starting to bend the laser cut 2mm plates.

Here is the result


So I did all 4 of them in 2mm. This is how the smallest bucket looks like
















the next bucket is a litter bigger


and then finally the largest bucket


and the line up

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Geschrieben von caterpilar am 25.09.2012 um 10:17:

 

This is the device I made to bend the buckets. Is made out of 50mm tubing and MDF scrap material.



I fixed the tube with screws

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Geschrieben von caterpilar am 25.09.2012 um 11:07:

 

I prepared all the buckets for welding with Easyweld. Once that is done, the second side plates will come on



The bucket teeth





I have plenty of teeth to fit them to all buckets if needed


The cover for accessing the battery and pump room


and the seat...




its coming together quiet well

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Geschrieben von caterpilar am 26.09.2012 um 09:31:

 

Some more pictures of the built:





I finished off the boom yesterday:









Then I cut a small part of the back of the seat to make it fit perfectly in the cabin:

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Geschrieben von caterpilar am 03.10.2012 um 10:40:

 

I measured the distances for the cylinders. Now I can start ordering them.



The manufacturer finished off a few more kits. Quiet impressive what the laser can do...



The placement of the parts on the Aluminum sheets are showing quiet some space between the parts. Fitting parts closer to each other will not give a great end result due to the heat generated by the cutting process.