PC1800 Front Shovel (1/12)
 

Started building the PC1800 with a plywood profile the same way that I started the D11 and 777 build. I will be using the original tracks I had on the dozer but will need to add 10 more links and pads, keep in mind I'm not building a true scale model of the shovel but will try to keep it much the same as full scale.

[IMG]http://i1291.photobucket.com/albums/...psbet0ntz5.jpg[/IMG]

I have made some progress already with this build and will upload more pics and info in time.

Re: PC1800 Front Shovel (1/12)
 

Swing bearing build using 200 - 1/4" steel balls and when completed is about 9.375 in dia.

[IMG]http://i1291.photobucket.com/albums/...psykarofxi.jpg[/IMG]

[IMG]http://i1291.photobucket.com/albums/...ps6ipf868n.jpg[/IMG]

[IMG]http://i1291.photobucket.com/albums/...ps3dlhiy4h.jpg[/IMG]

[IMG]http://i1291.photobucket.com/albums/...psqemudirz.jpg[/IMG]

[IMG]http://i1291.photobucket.com/albums/...psbfor3spe.jpg[/IMG]

I will be using a sprocket and chain for the swing , this will allow me to put the swing drive motor in under the cab or in a spot that is not needed for something else.

[IMG]http://i1291.photobucket.com/albums/...psvnpsrisz.jpg[/IMG]

[IMG]http://i1291.photobucket.com/albums/...psfhyokyvi.jpg[/IMG]

[IMG]http://i1291.photobucket.com/albums/...psdfpdmgfg.jpg[/IMG]

Still need to install the top and bottom seals on the bearing as well as the spacer to get the proper height. Hope this all works...LOL

Re: PC1800 Front Shovel (1/12)
 

I will be trying these air cylinders on the shovel not sure how well they are made but I'm going to find out. The main boom cylinders are 1.25" ID and the rest are 1.0625" ID. Hopefully the 5/32" tubing will have enough flow.... I'm going to find that out as well. :D

[IMG]http://i1291.photobucket.com/albums/...psxfsvipwx.jpg[/IMG]


I also plan on using a full scale valve body and pump , I will need to change the operating pressure in the valve down to 200-250 psi and the pump will need to turn at about 1500 RPM to supply enough volume for the cylinders, not sure if I can get this all to work as I would like but it's worth a try...the other challenge will be getting it all to fit in the model....time will tell.


[IMG]http://i1291.photobucket.com/albums/...psbd7no19a.jpg[/IMG]

Re: PC1800 Front Shovel (1/12)
 

Princess Auto strikes again!lol I'm liking what you're up too! I think one of the other guys on here used some valves like that in a couple of excavators and they worked alright. What is the plan to spin that pump with? 3408?lol

http://rctruckandconstruction.com/sh...ighlight=pc650

Re: PC1800 Front Shovel (1/12)
 

Nice work on the slew ring :)

Re: PC1800 Front Shovel (1/12)
 

Since I'm a Komatsu guy, I've been waiting for this build to start. Great work on the swing bearing! Don't know if it will be a problem, but sometimes when a main relief valve is adjusted well-below its normal operating pressure, it is not very consistent or accurate. I'm guessing this system has an original pressure of 2500-3000 PSI, dropping to 250 PSI might be a problem. Hope it is not for you. Should you need additional technical information about the full-size PC1800, let me know. Be glad to assist.

Ken

Re: PC1800 Front Shovel (1/12)
 

I am also glad to see this build start. I am not a hydraulics guy but I will follow this all the way. Nice work so far. Post lots of pictures.

Re: PC1800 Front Shovel (1/12)
 

Yes good ol princess auto...lol...the valve body and pump are from them (got them on sale too heehee) the cylinders are from Automation Direct. Not sure yet what motor will be used on the pump yet, need to turn it at 1500rpm to get the flow needed but I don't actual know how strong the motor needs to be, if I put in a motor that is to big it will just eat battery power. Still need to try runs some tests with pump RPM and see what flow rate is like, going to just use a cordless drill to do the tests on the pump three speed drill will give me some ranges to play with. You would need two 3408 engines to run the full scale shovel.....even then two kitties might not be enough....lol

Re: PC1800 Front Shovel (1/12)
 

Thanks.......it looks simple enough but was tricky to make....my first mistake was using a three jaw to turn it , should have use a four jaw but got lazy and didn't change chucks and started to get some vibrations in the cuts near the finished size, sometime short cuts aren't short cuts at all.....just end up spending more time trying to fix thing.

Re: PC1800 Front Shovel (1/12)
 

You might be right about the relief valve not liking the the low pressure, I wasn't thinking of that style of relief valve in there not a simple ball and spring, if it wants to float around at the low pressure I will need to add an external one on later to correct it....l will try it first and and see what it will do...maybe just maybe it will work with the low pressure.
Do you work on this machines or operate them??

Re: PC1800 Front Shovel (1/12)
 

I'm glad to see this build start too.....lol......I'm with you on not being a hydraulics guy either so this means we can learn together, this is the first time for me making something like this with hydraulics so I do have some learning to do!!! It will be interesting using things that aren't really designed for what I want them to do.....should be fun LOL
I will try post lots of pics.....did I post enough pics of the 777 build?? I always think people don't want to see every little step in the build....if there is something you want to see more pics of just let me know, be glad to post them for you, I usually take to many pics anyway....

Re: PC1800 Front Shovel (1/12)
 

We want to see every step! This place hasn't had enough scratch build pictures lately! Cooper can't carry the whole site on his own.lol

Re: PC1800 Front Shovel (1/12)
 

I'm a technical trainer for a Komatsu distributor in Kentucky & Indiana. Mostly, I teach our technicians but sometimes do troubleshooting classes for customers. Our territory has shovels up to the PC5500 and trucks up to 240 tons, but with the coal market going to h3ll, many of the larger machines are being parked.

Ken

Re: PC1800 Front Shovel (1/12)
 

I agree with RCP-I want to see everything!! A scratch build and a front shovel. It just doesn't get any better than that for me. I prefer the older cable shovels but I guess they are on the way out. Hydraulic machines take a lot more maintenance and do not last half as long but I understand that is what the companies want today.

Re: PC1800 Front Shovel (1/12)
 

All what those guys said...^^^^^^^^^. Cracking work on the swing bearing too...:cool::cool::cool:

Re: PC1800 Front Shovel (1/12)
 

Wow, great work on the swing bearing!! I've tossed around the idea of making bearings. Can never find the right size and if I do it's $$$!!! Yup, keep the pictures coming, I usually post pics because I need a break or because something just isn't working out and it's just enough to walk away and regroup:). Speaking of that, how is that motor gearbox holding up on the haul truck? This front shovel is going to be a big boy!! Any guess as to how much it may weigh when done??

Re: PC1800 Front Shovel (1/12)
 

Thanks....I was originally going to buy some big tapered roller bearings for the swing bearing and like you changed my mind after finding out the price, so desided to try build a bearing (was most likely cheaper to buy the bearings if a person considers all the time spent in making it...lol) one thing I like about it is it will transfer the load over a big area unlike some of the models using a small bearing. This model will be heavy and if I did the math right should be able to lift between 80-100lbs or I could just be fooling myself into believing that! :D

The banebots motor gear box has held in there so far, have stretched the#25 chain and have needed to tighten it a few times but the motor hasn't given any troubles yet...knock on wood...you know how that works...watch the next time I use it something will pile up :lol: I want to tear it apart and look at the gears and see if there is any possible failure about to happen, or at the very least clean it and apply new grease....pulling the motor out of that truck is not much fun so I think that's why I haven't yet;)

Not sure how heavy it will be, if I had to guess I would say it will be in the 140-160lbs range but I could be completely out to lunch on that guess, may even end up being heavier...lol...knowing the size of it and the way I build stuff it will most likely end up being 200lbs HEEHEE

Re: PC1800 Front Shovel (1/12)
 

Awesome!!!! Now I know who's brain to pick for info!! Finding good reference pics on line for this machine has proven a challenge....so I'm cheating a bit by looking at the PC2000 which has a great deal of similarities to the older 1800. I was almost going to switch the build to a 2000 but decided to keep going with the 1800. One thing I like about the 1800 in the length and size of the body/house section, gives more room for the full size valves etc, the modular design of the 2000 just wouldn't work. I do however like the overall looks of the 2000 over the 1800 but the design of the 1800 will be somewhat easier to build.

Is it OK to post reference pics from the online Komatsu brochure of the shovel...I would like to post one of the pics with all the size references on it ? Or if anyone else knows the answer let me know....that would be great !

Re: PC1800 Front Shovel (1/12)
 

Not an expert, but if wanting to post something that is from Komatsu's public website, I'd say no problem since it is not being using in a derogatory or for-profit way. Might list the link you got it from.

Just my opinion.

Ken

Re: PC1800 Front Shovel (1/12)
 

Here are the dimensions of the full scale PC1800 that I will be using to help build this model.

[IMG]http://i1291.photobucket.com/albums/...psjfzipqmr.jpg[/IMG]

This info was found here

http://www.komatsu.com.au/AboutKomat...6/PC1800-6.pdf

Some specs for the full scale machine

Twin 454HP engines
Swing speed 4.5 RPM
Max speed 1.7 MPH 2.7KM/H
Number of track pads/shoes 49/side
Weight with 40" triple grouser 405,910 LBS (184,120kg)
(1/12 scale is about 235lbs....yikes)
Bucket breakout force 81 tons
Bucket size 14.4 yds , 127" wide (1/12 scale is 10.6" wide)

Hope this will be of interest....Thanks for looking

KP

Re: PC1800 Front Shovel (1/12)
 

hello
very good job
like other projects , truck and bulldozer
I want to see the excavator to work :)
good luck

Re: PC1800 Front Shovel (1/12)
 

Finished putting the swing bearing together c/w seals and spacers, needed to add spacers to bring the overall height up to what was needed, I didn't have thick enough material to make the bearing tall enough to start with so it will be 4 pcs total instead of two.The total height of bearing c/w spacer is just over 2".

[IMG]http://i1291.photobucket.com/albums/...psh5aby3wn.jpg[/IMG]

[IMG]http://i1291.photobucket.com/albums/...psnh4sin9p.jpg[/IMG]

[IMG]http://i1291.photobucket.com/albums/...pszoddltr1.jpg[/IMG]

[IMG]http://i1291.photobucket.com/albums/...ps8uew7kao.jpg[/IMG]

[IMG]http://i1291.photobucket.com/albums/...psjmgsf1jg.jpg[/IMG]

[IMG]http://i1291.photobucket.com/albums/...psyxwgegiz.jpg[/IMG]

[IMG]http://i1291.photobucket.com/albums/...pszqytzzh8.jpg[/IMG]

[IMG]http://i1291.photobucket.com/albums/...pszy62bolj.jpg[/IMG]

[IMG]http://i1291.photobucket.com/albums/...psg8qplnxq.jpg[/IMG]

[IMG]http://i1291.photobucket.com/albums/...pscc5paidv.jpg[/IMG]

Thats all for now......KP

Re: PC1800 Front Shovel (1/12)
 

Great project, thanks for posting) When able to scratch build a fantastic swivel bearing like that, I was betting you also would be building scale replicas of the original cylinders;) But hey, if there is already some stuff out there on can get hold of that is about the correct size and can take the pressure, one can save time naturally.

Re: PC1800 Front Shovel (1/12)
 

Howdy KP, judging by your dimensional drawing, an electric ac 1/4hp furnace motor might fit. RPM1750 ;)

Re: PC1800 Front Shovel (1/12)
 

Howdy Joe......to bad I dont have any fan motors around like that,would almost fit....LOL....just need a long extention cord and never charge another battery.:D

I did run some red neck, high tech tests using a cordless drill though :p....turns the pump at about 1400 RPM no load, at that RPM the pump is moving about 51cc / sec which is a bit more than I need, could slow it down a bit more.
2.2cc / rev X 1400RPM = 3080cc / min. Rember this is no load very little restriction in the system ( I did need to increase the intake hose to 5/16" ID hose, the pump did not like trying to pull that much oil through the 1/4" OD tubing which is what you see in this picture)

[IMG]http://i1291.photobucket.com/albums/...pscnrnbbcw.jpg[/IMG]

Re: PC1800 Front Shovel (1/12)
 

This was the next test c/w valve and one 1.0625" ID x 6" stroke air cylinder, I have a 40lbs load on the cylinder. I replaced the spring in the RV with a lighter one that I thought would work and with a small adjustment it holds the desired 250PSI very well , really glad this worked :D:D This valve has an open center which means when all the spools are closed the flow is allowed to return to the tank with very little restriction which should help increase run time on the battery.

[IMG]http://i1291.photobucket.com/albums/...psh0mifswq.jpg[/IMG]

Re: PC1800 Front Shovel (1/12)
 

Here is a short video of the high tech test....:)

[IMG]http://i1291.photobucket.com/albums/...ps1nf5zymt.mp4[/IMG]

Re: PC1800 Front Shovel (1/12)
 

I love the testing! It's not too late to build a seat on the counterbalance so that you can sit on it and control it. Why waste money on a remote!

Re: PC1800 Front Shovel (1/12)
 

if you're gonna go that far, why not just go straight for 1:1 scale. Much more space to package everything inside :D

Re: PC1800 Front Shovel (1/12)
 

Is that a furnace oil pump? friend of mine works on oil/gas furnaces and tossed me a few, I've been wanting to make a test on them. He did tell me they can produce some really high pressures. Looks like your redneck testing is not so redneck,,,, lol!! Nothing broke ,, haha. Naa man, stuff looks good!!! This is going to be a monster!!!

Re: PC1800 Front Shovel (1/12)
 

Haha...lets see if I use a furnace fan motor that Joe suggested with a long ext cord and install a reclining seat c/w beverage holder, small screen TV, sound system, small fan for hot days and a cooler this could turn out to be a mans best friend!! :lol:

Re: PC1800 Front Shovel (1/12)
 

Nope, not a furnace pump......got it on sale at Princess auto

http://www.princessauto.com/en/detai...or/A-p1220030e

You might like this thread....

http://www.rctruckandconstruction.co...hydraulic+pump

SURPRISINGLY nothing broke...lol...but things didn't all go as planned.... the return line from the pump to the oil jug decided it didnt like being inside the jug anymore, well ya know the rest...big mess really fast!!! I was so glad the whole thing was working I didn't even swear....much. :D

Re: PC1800 Front Shovel (1/12)
 

Thanks!! Decided to try use some off the shelf air cylinders that are close to the needed sizes instead of building them, time will tell how well they will work and or for how long...lol

Re: PC1800 Front Shovel (1/12)
 

I have a question or two for all you hydraulic fellas on here.....

What type of oil filters are being used in models , are there inline and intank
filters??
How much would these small filters effect the flow if the needed volume is greater than the typical RC system??

How big should the tank be in regards to the total volume of oil in the system, should the tank hold the same amount or more, or can it be less providing the oil temp doesn't get to hot? I can't see the temp of the oil in this model being a problem....there will be about 700cc in the system not including what will end up being in the tank, which is one more thing that still needs to be built. I would think that the longer the model is being used the warmer the oil will get....how warm does the hyd. oil typically get in your machines??

I have limited knowledge in regards to hydraulics and no experience with RC hydraulics...zero...so be patient with me as I hope to learn more from all of you and of coarse the good ole " school of hard knocks"

Re: PC1800 Front Shovel (1/12)
 

Hello Dadsgarage,

In a normal machine, the tank volume is about the same size as the system volume. I would do the same on a model. Maybe a little more to be sure and to have better cooling.
Unfortunately I do not have experience with oil in scale models yet.

Your build is great! I really like the scratch build parts.

Re: PC1800 Front Shovel (1/12)
 

i alway thought it was double the cylinder. 30 gallons in the piston
30 more in the tank. thats how it is on my dump trailer 60 gallons
in the tank when the piston is down 30 left when full lift.

what about a inline carb filter on the return side as long as it not under pressure

Re: PC1800 Front Shovel (1/12)
 

http://www.ebay.com/itm/Inline-Fuel-...pVuezG&vxp=mtr

I wanted to use this (fuel) filter in my stuff but it is too big, probably good for this size model. Oil filter/fuel filter, they both are trapping particles of a certain size, 5~500 microns,,, the ones I use are very small disposable I get from McMaster. I have to drill out ends and thread for m5 fittings. I'm sure they are way too small for this. My opinion on hydro volumes is about same as above, double the system volume and you'll be good. On an hydro guys side, as big of a tank as weight/size/practicality allows. More oil is just better all way around. Temp, contaminants, lifespan of oil, ect. But on 1:1 machines, lifespan, cost of replacing, and available size is what restrictions are. One thing to try is to have tank suction on bottom and tank return line on top (baffle or just opposite side) allows air in oil to migrate to top and not back into pump. That's the frothing of agitated oil, a lot of oil has additives to lessen foaming. I've never had temp come into issue in any of my models. Excavator cylinders get warm after a hour use in summertime, but never hot. (At least that I am aware of:) )

And that school you talk about, one of the best I've ever attended!!! :)

Re: PC1800 Front Shovel (1/12)
 

Love the 777. This build is going to be great. It's going to influence me when I build my excavator. Using regular parts. I like it. Keep up the great work.

Re: PC1800 Front Shovel (1/12)
 

Thanks for all the feed back on the hydraulic questions, now I will have to put it to good use....

Next trick will be getting everything to fit, even though this is a good size model there isn't a lot of extra space left over after all the "big goodies" are in place. Played around with different placements of everything on a plywood template, this seems to be about the best use of the space....the rusty 2"x4" HSS may end up being used as the tank, after getting a good cleaning and cut to proper length it will hold about 1000cc. I dont have the drive motor yet for the pump, it will be belt drive with about 3:1 reduction using a small 2L vbelt. The servos will be mounted on a plate above the motor/pump, the handle shafts on the valve will be cut shorter and then connected to the servos with ball linkage rods. Nothing to exciting but here are some pics....

[IMG]http://i1291.photobucket.com/albums/...psujyoxrty.jpg

[IMG]http://i1291.photobucket.com/albums/...psb8ouoacf.jpg[/IMG]

[IMG]http://i1291.photobucket.com/albums/...psa4lmaspp.jpg[/IMG]

Thanks for looking!!
KP

Re: PC1800 Front Shovel (1/12)
 

How many amps is each battery?