Total newbie dozer process

[baker3]

Well I figured I would show my progress so far on my build!! Finally got the servos for the main drive fit and mounted. Now waiting for Radio and motor controller. Thanks to everyone for the mass amount of help!!

[baker3]

So here are some updates as I wait for my servos, ESC's and radio to arrive in the mail. I finished hacking up the rams in preparation for the servo type screw drives.

[baker3]

They work just as they should...with a drill for now.

[baker3]

Here are few updates...machined down the screw and threaded it to thread into the servo gear and mounted them up.

[Lil Giants]

Did you locktite or use a locking nut to secure the thread rod to the servo?

[baker3]

I used red locktite and its been holding up really good.

[baker3]

As I still wait on parts, I decided to do a first test run.

[baker3]

After finally finishing the dozer, I been thinking of painting it like this. What is your opinion?

[cabs]

That would look bad a%$ even though its a cat

[baker3]

Yesterday we got some snow so I decided to have some fun with the dozer. I ended up breaking the plastic ram arms that connect to the blade so I am fabricated some out of steel brake line and waiting on my masonry bits to get in since the machine screws are way too slow.

[baker3]

Just a few updates:So I tried to build servo operated rams but had no welder but found a pretty easy and cheap way to do it that is just as strong as a weld. I spent countless hours working with epoxy and JB weld just to have it fail every time! So all you need is:1/4" masonry bit(I found 10 pieces for $6 shipped on Ebay), Acid Core Solder, Soldering Flux and brake line, scrap pices of steel rod. I used 3/16 brake line, solder wont stick to stainless steel. I first cut the brake line down to the length I need. Then I grind down the steel rod to fit into one end of the brake line and drill a hole for mounting. Solder the 2 pieces together and yes it is STRONG! Then with a smaller piece of steel rod as shown, I grind it down like a dome shape. This is the piece that the Bit will travel on. Solder that in place then snip and grind down. The trick to that is getting the steel rod ground just right so its not too tight and not too loose. Then mount. Here are a couple pics. I didn't expect this to work so well but it did. I will take more pics and provide more details if needed.

Here is the piece the bit will travel through. You can see the small piece of metal ground down inside the brake line and soldered on the outside.

Here is the finished product mounted. The only part I did have to use JB weld was the attach the bit to the servo horn. The solder wont stick to the aluminum servo horn.

Hope this helps and if anyone has questions please feel free to ask. Total build for the screw operated rams: 10 masonary bits for $6 shipped, 4 micro servos $14, 3/16" brake line $5-$8 depending on length. Solder, flux and soldering iron about $15. The rest of the metal rods were scrap I had from household stuff. Pretty cheap and very reliable and strong for someone with no access to a welder.

[Rvjimd]

Very informative, thanks for the detail!

Do you need to be careful to not over run at either end of travel to avoid trouble? Would there be any way to build in a free travel at one or both ends?

Are you tapping the threads on the net of the drill bit that inserts into the servo? How are you turning down the diameter on the drill bit at that end, isn't the drill bit really hard?

Jim

[baker3]

You do need to be careful not to over run it when raising the ripper. I just familiarize myself with it and try not to over work the servo when the bit hits the mounting rod. When lowering the ripper, the bit just falls out so no big deal there but again just familiarize. As for a free travel piece, I suppose you could solder two pieces of steel at one end on the outside of the brake line then mount it somehow allowing the bit to travel through. I just may try that. As for turning down the bit, I have a pretty primitive way of doing this lol. Insert the bit backwards into a drill then I use my table grinder to grind down to size, then into a point to insert into the servo horn. I have tried machining the bit down then threading it but it was more of a pain than its worth. The bit is hard but by using the drill, I keep the bit spinning while I grind it down. This helps me not burn my fingers and get a somewhat constant and even grind pattern with little to no uneven spots, if that makes sense.

I will take some pics today and get some posted.

[Rvjimd]

Cool, your turning method sounds very similar to how I did it on my crane conversion. I think I put a video in the thread of how a turned down a gear for the crane body pivot.

Thanks for the info!

Jim

[baker3]

So here is my method of turning down the bit:

After the bit has been turned down to fit into the servo horn, I place a small amount of JB Weld in the servo horn.

Then, I place the bit in the servo horn. I then power the servo to adjust the bit to get rid of any wobble and to get is to spin as straight as I can. Let the JB Weld set for about an hour. This should hold the bit firm but still allow to adjust the bit if needed before placing more JB Weld around the whole base where the bit enters the servo horn.

[baker3]

Oops, 2 of the same pics. Here is the one I meant to be last.

[Rvjimd]

Thanks!

I can't believe the JB Weld holds. I have done servos on my crane that way, but I tap the rod and then run a jam nut onto the servo. Sometimes I drill a cross hole and put a pin thru it as well. I'm going to have to try the JB Weld method.

Is it a pretty tight fit or don't you worry too much about it, expecting the JB to hold it?

Jim

[baker3]

Ya, the JB Weld holds very good so far and I have jammed up the masonary bit in the brake line. The servo stalls without the JB Weld busting loose. This is the only part that JB weld has not failed on me yet lol.(knock on wood). After the first amount of JB Weld has set and I am happy with the bit spinning fairly straight with no wobble, I then apply JB Weld like this.

Here is a pic of my blade ram setup.