He is at it again! 1:50 Dozer Conversion
 

Well, here I go again! Bought a new dozer and it went directly to the bench.

Man, this is really TINY!

http://i1291.photobucket.com/albums/...ps2326127e.jpg

Machined off two out of three teeth on a 21 t pinion to drive the tracks.

http://i1291.photobucket.com/albums/...ps8fee73a9.jpg

I'm gona have to pull a scraper or something just to find space for a battery and RX!

Jim

Re: He is at it again! 1:50 Dozer Conversion
 

Go Jim!

This rx is 14mm wide:

http://www.hobbyking.com/hobbyking/s..._Receiver.html

Hey, i spy a ...a 1/32 slotcar crown gear in one photo..:D

Re: He is at it again! 1:50 Dozer Conversion
 

Slot car crown gear? What? Where? That was supposed to be top secret!:D

(It pays to have a jillion hobbies, I find all sort of small parts from the others to use in my conversion attempts!)

Jim

Re: He is at it again! 1:50 Dozer Conversion
 

Wow, that is a sharp looking model! This will be very interesting to watch. I don't think I've ever seen a documented thread on RC'ing a 1/50 scale diecast model. Very cool.

Re: He is at it again! 1:50 Dozer Conversion
 

wow! never even thought of slot car parts! man the things that just jump at you when you finally see them!!

Re: He is at it again! 1:50 Dozer Conversion
 

Well, I kept at it and got it moving but the poor thing got hacked up way more than I wanted. I learned from the process, like you can't convert any darn thing you want you dern fool!

There is no room for a battery or RX. I thought about pulling a scrapper Nd hiding that stuff in the scrapper box, but that doesn't really fit with the sand and coal barge hauling setup I have going.

Here is the bench test video.

http://youtu.be/tNZDnqNWHHM

Jim

Re: He is at it again! 1:50 Dozer Conversion
 

Pull 2 scrapers, and fill 1 with batteries & fake dirt!
Cheers, Neil.

Re: He is at it again! 1:50 Dozer Conversion
 

Very cool. It really puts it into perspective when you lower the blade with your finger.:)

Re: He is at it again! 1:50 Dozer Conversion
 

I am gona stew on it for a day or two and see if I can come up with any good ideas on stowing the battery and RX. I would like to add a blade control as well, won't be to practical without that. I have even thought about some form of a cam on the blade to lift the blade when backing up and drop it going forward. There is absolutely no more room in the engine compartment for a third servo.

Back to making the big gear in the dragline go around. I have room for the fifth servo there, just trying to figure out how to make it work from the TX point of view.

Jim

Re: He is at it again! 1:50 Dozer Conversion
 

You should look into the lipo packs for the micro helicopters. They have them from

120MAH http://www.hobbypartz.com/77p-minili...-15c-1s1p.html

to

350 mah http://www.hobbypartz.com/77p-minili...-15c-1s1p.html

These are real cheap so you could buy several even if you had to change them out more often. I dont think you can get more power in a smaller package.

Re: He is at it again! 1:50 Dozer Conversion
 

That's awesome! Perhaps you could build a cab and hide some components inside it?

Re: He is at it again! 1:50 Dozer Conversion
 

Thanks for looking, and for the tips. I am sort of looking for a bit larger style dozer in 1:50 scale. I'm thinking a high drive model with a cab so I will have more room to work. What I really need it to see one in person so I can pick a good donor dozer. I have seen one or two, but each with problems that keep me from buying one.

I do have some small heli packs. I might just saddle them on somehow and get the poor thing moving until the new dozer comes along. Trouble with me, is since I can't see how I'm ever gona get the blade on it, and working, I just sort of give up on it.:o

Jim

Re: He is at it again! 1:50 Dozer Conversion
 

Give it a break - sit it on the shelf - and think on it - give the ol gray matter time to crunch it through.

I hear pager motors can make nice little screw drives.

Re: He is at it again! 1:50 Dozer Conversion
 

My solution was to go bigger! Here is a short video of my 1/16 (seems small to be called 1/16) spec cast die cast dozer. Used micro servos with a pinion pressed on the top spline and slot it crown gears.

http://youtu.be/fu1EAJIgZzo

Jim

Re: He is at it again! 1:50 Dozer Conversion
 

Where did you get the model? Looks like a really great conversion.

Re: He is at it again! 1:50 Dozer Conversion
 

There is a local die cast place here in Des Moines that carries mostly Ag stuff but they always have some construction stuff also.

Jim

Re: He is at it again! 1:50 Dozer Conversion
 

What/who makes is it?

Re: He is at it again! 1:50 Dozer Conversion
 

Wow, that's a nice conversion! It runs really smooth too. Any photos that you could share of the model? I wonder how well the tracks will hold up, or if they will clog with dirt.

Re: He is at it again! 1:50 Dozer Conversion
 

I just got it going and expect I'll have some adjustments to make before long. I also don't have the blade hooked up yet and I should be able to get that working as well.

The tracks are going to be trouble. Ther roll really nice and free, but anything in the links causes trouble. I have a few ideas, but I'm going to finish the blade control first. It may become more of a clean surface machine if I have too much trouble with the tracks. The biggest problem is the scale. Seems like small grains of sand not only get into the links and clog up when the sprocket comes around, but the treads also bind up. I may try to clean out some of the paint where it is real tight, but that is on the back burner for now.

I'll get some photos of the details of the drive system in a day or so...

Jim

Re: He is at it again! 1:50 Dozer Conversion
 

Jim, your 1/16 conversion runs nice. Nice job.

On my cable excavator i had to "sharpen" the cups between each tooth so that basically just about a knife blades width actually touches the tracks so that dirt doesn't bind it up.

Re: He is at it again! 1:50 Dozer Conversion
 

Scott,

Ya, I remember you telling me that about the cog wheels, I'm probably going to try that at some point.

Rcp, the machine is made by SpecCast. Is is labeled as 1/16 scale, Oliver OC-12 crawler with blade. They make a version without the blade for about $5 less. That one comes with an umbrella.

Here is a picture of the SECOND one I just bought today along with a few build pictures I took.

http://youtu.be/zWuuw7ka4qE

Jim

Re: He is at it again! 1:50 Dozer Conversion
 

Scott,

Do you have a pic of the knife edge on the cog wheels? When I read the last post, I made me pause. I would have shaved off the points? Now I'm confused...:confused:

Jim

1:16 dozer w/blade control video
 

Got the blade control working. I'm happy with the overall function of blade and tracks. I need to see if I can find some metal crown gears to use in place of the plastic slot.it crowns, they are not going to take the abuse.

And I need an operator! Are there 1:16 scale figures that would work for me as an operator? Would I find something like that at walmart or a toy store?

http://youtu.be/JG2plmeSXEo

Jim

Re: He is at it again! 1:50 Dozer Conversion
 

It runs great Jim, good job.

Bruder people are 1/16 and look ok.

i tried to take pictures of the drive sprocket teeth last night and it just doesn't show how i modified them.

Give me a call today and i'll try to explain it better on the phone.

Re: He is at it again! 1:50 Dozer Conversion
 

This is great, is the blade hydraulic?

Re: He is at it again! 1:50 Dozer Conversion
 

Jack,

No, everything is micro servo. The blade lift servo just pokes out the right side where a standard one leg servo horn is attached to the blade frame with a short piece of wire. I'll get some more detail pics eventually, once I get it all refined and work out some bugs.

I'm putting on two new pinnion gears this morning, the first ones I made too thin and they would not stay aligned good enough. Got a second pair and made them a bit taller.

Jim

Re: He is at it again! 1:50 Dozer Conversion
 

Jim, I was searching for stuff on the forum and found this thread, didn't know if you've seen it, check out the first post!
http://www.rctruckandconstruction.co...e+truck+forums.

Re: He is at it again! 1:50 Dozer Conversion
 

Ya, I had seen the video once before. The more I work with the ginger stuff, the more I like it. And the 1/16 STILL seems small even after working on some 1:50 stuff!

Here is the latest video of my 1:16 dozer. I have switched over to gear motors for the drives. I'm installing a wedge now to hold the motor and pinion up against the crown gears. I am still searching for replacement crown gears. I'm using the blue slot.it crowns now I think they are 24 or 26 tooth,but the plastic is not going to hold up.

http://youtu.be/1VZZfcgRaB4

Jim

Re: He is at it again! 1:50 Dozer Conversion
 

Looks like it works great, seems to be smooth but sounds like gears jumping towards the end, or is that just normal track noise? Anyway nice job!

Re: He is at it again! 1:50 Dozer Conversion
 

Truck maker,

That was probably the pinion slipping on the plastic crown gear. I'm in the middle of yet another version. I'm making the rear end of the chassis out of aluminum angle stock so I can position the two drive motors where I want them and I'm using two steel pinions instead of one steel and one plastic crown.

Film at eleven! ;)

Jim

Re: He is at it again! 1:50 Dozer Conversion
 

Really nice work on the conversion jim- you said you are making more changes so this should be a fine model when completed. Any updates on the wooden crane with the clamshell?

Re: He is at it again! 1:50 Dozer Conversion
 

Tom,

Thanks for the comments. I hadn't heard from you in a while, wondered how you were getting along. We are coming to Florence in a few days to check on the boat.

I haven't done anything to the wood crane since we got back from PA. I still need to paint it and I want to rebuild the cab. I slapped on a balsa cab but it needs to look better than it turned out. :o

I ordered some stronger versions of the gear motors that should make the dozer work really good. I have a few more details to take care of but I basically have the aluminum rear end finished and tested it yesterday. Works good but the low power motors I have on it no are just a bit to weak and they stall just about when it should start to slide a track.

I also ordered some new speed controls that I hope are smaller than the HK xcar 45 ones that I'm now using. They are just big enough that it is hard to cram it all under the hood.

Here is a pic of the chassis mod.

http://i1291.photobucket.com/albums/...ps75086390.jpg

Jim

Re: He is at it again! 1:50 Dozer Conversion
 

hi im new to this, been a gm mechanic for a few years now, not sure what kind of voltage your looking for but some of our remotes use a 12volt battery smaller then a AAA they last for an average of two years running a lcd display, if it helps for your size restrictions, also it you need lower voltage for your reciever you can drop the voltage with a diode or several each diode will give you roughly .5 volt reduction

Re: He is at it again! 1:50 Dozer Conversion
 

Hi John, welcome to the forum! I'm honored that you pick my thread for your first post!

The way it usually turns out, like on my dozer, you need at least one speed controller, which provides the voltage to a typical DC motor. The speed controllers also provide 5 volts for the radio reciever which will I turn power any servo motors plugged into the reciever.

Trouble I'm having is that with the newer style brushless motors, the older style brushed motor controllers are harder to find in the smaller sizes. I DID manage to find some in china, so if they turn out like I hope they will solve my space issue.

As for battery power, the latest and greatest is LiPo, which has great power density. They can be a bit sensitive to charging/discharging and can be damaged if not treated right. One of the functions available on most speed controllers is low battery voltage cutoff, so the controller shuts down the output to the drive motor before the voltage dros below a threshold that would damage the battery.

Jim

Re: He is at it again! 1:50 Dozer Conversion
 

Mods look good jim, but I can see you need larger gearmotors for a dozer this size. I'm sure you will get it right.

Re: He is at it again! 1:50 Dozer Conversion
 

thanks for the info, i always wondered about the esc. your project looks great by the way, im used to building hot rods an thought id try something different im used to running d7 cats and 320 trackhoes from farm experience. started my first rc conversion on a jd 4x4 with duals but i used a damaged ford 150 rc truck for the controller and reciever only 2 channel but it did the job, but the next project is a cat hoping to either find d7 17a or simular. i have alot of mill experience. would you if you were to build another 1/50 scale use two motors or make a diff and have brake steering. i going to build a few bigger ones adn learn more about the electronics before tackling a small model, thanks again for showing your talent.

Re: He is at it again! 1:50 Dozer Conversion
 

John,

Your diff and brake question is a good one! I don't know for sure, but the guys scratch building the bigger tracked machines are all using two motors I think? I would guess that getting the brakes to work as smoothly and easily as using two motors would be harder than the simple two motor setup.

As you prowl around here on the site you will figure out the handful of guys with the bigger scratch machines and they should have a good answer.

Jim

Re: He is at it again! 1:50 Dozer Conversion
 

Tom,

I ordered three more sets of motors. They make three different versions of the motor in that size. I think there is going to be at least one that should work. What I have now is almost strong enough. On the bench, they feel real strong, but they need just a bit more grunt.

I think one set is a bit higher rpm and higher stall torque, so I'm hoping I can re gear for the rpm and get about what I need for speed and torque.

Jim

Re: He is at it again! 1:50 Dozer Conversion
 

ya your right, i had the idea of one soleniod sliding a pin either left or right to lock into the drive sprocket to positive lock, but it would not be as smooth as the two motors, thanks again, i dont know many people on here if i need a hand with the esc can i ask apon you?

Re: He is at it again! 1:50 Dozer Conversion
 

Jim,
You could always use the control board out of a cheap but powerful servo to use as a speed controller with smooth forward to reverse action.

You would have to add resisters to the servo board to give you "center" just like converting one for continuous rotation.

i am sure the control board in this servo could feed up to 2 amps to a motor and i doubt you would even draw 2 amps.

http://www.hobbyking.com/hobbyking/s...Fc07OgodjU8Alg