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Chilihook

Big Bear Build (Triple B)

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Well, that Big Bear I got of Fee Bay a few days ago now sits disassembled on my bench. Easily the filthiest model I have ever taken apart. Dirt and sand everywhere, very sticky dust, dead spiders in the tires, thick, lugubrious grease in the gears. Many of the bolts have corrosion on them. The tires, while being in okay-ish shape all have multiple flat spots. The tire inserts had their lips bent, almost like scallop shells - how do you do that? You'll see in the picture that one of the screws is not like the others - someone just jammed a screw that was way too big into the back of the wheel. Nice job.

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I'm guessing that when this was put away the last time it was run hard and put away wet, so to speak. Whatever double sided tape that held the ancient receiver in place was clearly made out of the material that they make the little black boxes out of that are on jets. Wish the whole truck was made of that stuff, it'd last forever.  Oh yeah, the front body mount and the bumper were broken.

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However I'm not deterred. As I go along, I'm sure I'll have questions... as a matter of fact I have one now - what is the best way of cleaning small metal parts? I was thinking of soaking them in mineral spirits or something similar, but not sure. Could always dowse them with Dawn dish soap and near boiling water. Was wondering what everyone else would do?

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Also a serious plus came with this Big Bear - an MIP ball diff. So the transmission won't bean issue. I hope. B)

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Big plus on the diff, I don't agree with ball diffs unless on a car used on a track but in the case of the Big Bear, anything that holds together is better than the factory unit. 

A lot of people here use ultrasonic cleaners to bring up the hardware, dish soap is known to advocate rust, so anyone with a love for 1:1 cars knows not to use it. 

It wouldn't be hard to hand make a new front body mount. Mine had the upper portion of the mount drilled into the front lip instead of the bumper so the front tyres would clear the panels/guards/fenders. It wouldn't be a silly idea to bend up a 1.5mm/2mm sheet of aluminum and leave a little extra at the top to lift the front of the cab.

All the best. Big bear is the granddaddy of RC Monster trucks

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nice find, especially with the ball diff. Any chance you can take some close up pics of ball diff when its been cleaned up?

I've seen the bumper bar come up on ebay reasonably frequently.

e.g., see this listing - http://www.ebay.com.au/itm/Vintage-Marui-Big-Bear-bumper-set-/201778478072?hash=item2efaef3bf8:g:0DMAAOSwA3dYZZlA

 

Or you can download a 3D design for both the bumper bar and body mount from thingiverse (https://www.thingiverse.com/thing:1079909) and get them 3D printed from shape ways.

These recent posts of Big Bears remind me that I need to get on with restoring mine!

good luck with it.

 

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+1 on the ball diff loads of pictures please and measurements if possible. Take a good look at the idler gear, any luck and that might be a MIP upgrade aswell.

as mentioned there are several parts available as 3D printable design. And I find shapeway very usable. Just take white and delayed shipment saves $$

cleaning remove the over access grease with brush or whatever then of in a ultrasonic cleaner those work wonders. Just don't combine alloys, brass and metal.

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I wish I had a sonic cleaner. Wonder if hydrogen peroxide would work? Or vinegar and baking soda?

  I found 3-d files online for the bumper, body mount, roll bar, and lights. Had the mount and bumper printed. Should be receiving 3-d printed parts from a local source in a couple of days. Great price, looking forward to seeing what they're like!

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Please do a detailed write up on the MIP differential. I just finished restoring a Big Bear documented in the Mauri section.  Keep posting pics and ask away any questions. I have learned a lot since I started my resto. 

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I'm likely not going to be taking the ball diff apart, just giving it a really good cleaning. I have a couple of pics of the assembly instructions from MIP from the diff was originally built. Also, here are a couple of shots of the diff , idler gear, and the spur gear on the no-name motor. The squares on the cutting mat are 1-inch square to give you an ide of the diff' size.

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1 hour ago, Macinnis said:

images give a 404 error

Thanks for the images Chilihook:

but it looks like somethings gone awry when they've been pasted in, if you cut out the extra code you get the links (well these worked for me):

https://postimg.org/image/eazxyk703

https://postimg.org/image/pytzt3w4z

https://postimg.org/image/m16q3p9bn

https://postimg.org/image/dueqc4j8z

https://postimg.org/image/sc7c6dl6b/

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That idler gear is a MIP for sure, could you make a pic from the other side.

Looks like machined steel two gears pressed together not one piece like the original.

That should make a bomb proof gear for the bear.

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9 hours ago, Chilihook said:

I'm likely not going to be taking the ball diff apart, just giving it a really good cleaning. I have a couple of pics of the assembly instructions from MIP from the diff was originally built. Also, here are a couple of shots of the diff , idler gear, and the spur gear on the no-name motor. The squares on the cutting mat are 1-inch square to give you an ide of the diff' size.

%5Burl=https://postimg.org/image/sc7c6dl6b/%5D%5Bimg%5Dhttps://s5.postimg.org/sc7c6dl6b/IMG_4760.jpg%5B/img%5D%5B/url%5D

%5Burl=https://postimg.org/image/dueqc4j8z/%5D%5Bimg%5Dhttps://s5.postimg.org/dueqc4j8z/IMG_4761.jpg%5B/img%5D%5B/url%5D

%5Burl=https://postimg.org/image/m16q3p9bn/%5D%5Bimg%5Dhttps://s5.postimg.org/m16q3p9bn/IMG_4762.jpg%5B/img%5D%5B/url%5D

%5Burl=https://postimg.org/image/pytzt3w4z/%5D%5Bimg%5Dhttps://s5.postimg.org/pytzt3w4z/IMG_4764.jpg%5B/img%5D%5B/url%5D

%5Burl=https://postimg.org/image/eazxyk703/%5D%5Bimg%5Dhttps://s5.postimg.org/eazxyk703/IMG_4765.jpg%5B/img%5D%5B/url%5D

 

And this is why you shouldn't post from your phone late at night. Sorry everyone and thanks for the pick up Waterbok!

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So I have been trying to think of a solution to amend the problem I have (or anyone might have) with the lack of re re tires for the BB. I ordered a set of Wild Willy 2 wheels and tires and a WW2 E-parts tree which has the hex hubs for the axles. I know that there are plenty of adapters out there for converting a Big Bear to Blackfoot wheels, but I don't want to go down that road and make this a "Black Bear" - although that sounds pretty cool - so I am going to go to work on fabricating Big Bear to Wild Willy 2 hub adapters.

Before I get super involved with this, they don't already exist someplace do they?

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I want that ball diff! My Big Bear is solid right now but that would make it so much better. 

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26 minutes ago, Macinnis said:

I want that ball diff! My Big Bear is solid right now but that would make it so much better. 

If you know of 248 other BB owners who want one... 

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4 hours ago, Chilihook said:

So I have been trying to think of a solution to amend the problem I have (or anyone might have) with the lack of re re tires for the BB. I ordered a set of Wild Willy 2 wheels and tires and a WW2 E-parts tree which has the hex hubs for the axles. I know that there are plenty of adapters out there for converting a Big Bear to Blackfoot wheels, but I don't want to go down that road and make this a "Black Bear" - although that sounds pretty cool - so I am going to go to work on fabricating Big Bear to Wild Willy 2 hub adapters.

Before I get super involved with this, they don't already exist someplace do they?

thats one issue with the Big Bear, the tires are a custom size, although some tires come close. There is older build on here that does a very good job of it, but I can't think whose that was.

A mate of mine is a movie prop maker as well and offered to help me make a set, but it would probably end up costing over $150 per set to make. I almost went down that path, but was lucky enough to find within a relatively short space of time 2 sets on eBay for a reasonable price. They do come up every so often.

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After thinking about it a while and seeing as the grease that was in the ball diff was more like glue after sitting for so long, I figured it should be degreased, cleaned, and then re-greased and packed with silicone grease. 

I was a bit nerve wracked with teeny tiny ball bearings on the loose, but everything went fine. The diff is now smoother and quieter than it was before. It was actually very easy to take apart, service and reassemble - I was pretty surprised.

Before

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With the spur gear

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Stripping the grease off

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Starting reassembly

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And after

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Nice work. I've never seen a Big Bear up close and mechanically.

Interested to see how this turns out.

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Could you measure the outer diameter of the MIP diff, is it 37mm? thx

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looks like 38mm

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Edited by Chilihook
misread the caliper
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Hey Chili, Um, I am hoping that wasn't Dawn you cleaned all the grease off with, but if it was, well it is done now. I think the best way I have found to date to degrease metal bits is Brake System Cleaner. I prefer mine to come from Advance Auto Parts as they commonly pull a sale for 2 cans for $5, but if they are not near to you, well, CRC and others make it, so you can use those, just go for the NON CHLORINATED versions. I use it in two forms, I can spray things with the nozzle straw and I also "decant" it into an old prescription drug bottle with a tight lid. The bottle is clear enough with no lable that I can see how dirty the fluid got and when it is time to change. Bonus points, it is easy to fish out the metal bits if they are magnetic. If you need a larger diameter bottle, I guess you could really go to town with a tight sealing jar or something, but that is a LOT of fluid to fill up something like that. I have kept my various bottles for a while and can shake up the contents to break free more dirt and gunk.


Sending you a PM on something you might use on this project.

Chris

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Forgot to comment. You called the motor "no-name" and it is a bit far from the truth. That looks to me to be a Speedworks Monster Mash and it was made by Trinity I believe, BITD. :lol:

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