Turbo Optima build - Project Barney: Finished

[Coelacanth]

Unfortunately this isn't much of an update, but things needed to be done. I had to grind down the axle ends of the Kyosho Lazer CVDs because there was a lot of rubbing inside the rear alloy hubs. The top is the stock CVD; the bottom one shows the cut-down flange.

The first step of the assembly (according to the manual) is to assemble the rear gear-box. I have the belt drive diffs, pulley, shaft, 2mm screws and some washers, but those little Lexan dust-covers to keep dirt out of the modded rear gear-box are impossible to find. I didn't want to just leave a gaping hole for dirt & crap to get inside the gear-box and mess up the diff, pulley & final pinion gear, so I had to find a way to fabricate my own cover. Once this niggling detail is taken care of, the majority of the build should move along a lot quicker.

It seemed to me that making a "sandwich" with 2 side pieces and a curved center piece would be the easiest way to fabricate this thing. Here are some pics of the pulley cover progress. I'll cement the center piece to the 2 side pieces with a bit of Weld-On (hopefully it'll work), then trim down the corners of the side pieces. When the gear-box is done, I'll seal any openings with silicone.

[Mr. ED]

Are those the low-cost UJ's for the lzaer zx5? Do you have a partnr and address for buying?
(The CVD's are great but so expensive)

[jwscab]

Marc,

you can get polycarbonate glue if needed to glue together that dust shield, they make a few different types, one is very thin and it more or less melts the two pieces together, and then there is thicker stuff.

thanks for the photo of the zx5 universals.....how long are they from the face of the plastic on the axle to the bone pin?

[Coelacanth]

I'll find that info for both of you tonight. I paid maybe $20 a pair for those CVDs after watching eBay patiently and finally seeing a low price on them.

Back in the day when I was modding computers and doing a lot of custom work with acrylic, I bought a couple varieties of Weld-On, as Joe mentioned one is more of a goopy viscosity (in a tube) and the other is a runny liquid (in a can). I know it works fantastic to cement acrylic, and is supposed to work for polycarbonate as well...

Bought it from Ridout Plastics:

http://ridoutplastics.com/adandcem.html

[Coelacanth]

Are those the low-cost UJ's for the lzaer zx5? Do you have a partnr and address for buying?
(The CVD's are great but so expensive)

Mr. ED, I'm pretty sure this is what I bought, but this is even cheaper than what I paid. I bought them in 65.5 & 68mm lengths, as the GPM rear arms are approximately 5mm longer than stock Turbo Optima arms. Stock dogbones are 62.5mm so I figured one of those ought to work.

http://www.ebay.ca/itm/Kyosho-LA303-UNIVERSAL-SWING-SHAFT-65-5-PLASTIC-JOINT-/220789950245?pt=Radio_Control_Parts_Accessories&hash=item33681b4725

And another seller:
http://www.ebay.ca/itm/Kyosho-LA303-Universal-Swing-Shaft-65-5-P-Joint-Type-/130496829586?pt=Radio_Control_Parts_Accessories&hash=item1e62379892

[Coelacanth]

thanks for the photo of the zx5 universals.....how long are they from the face of the plastic on the axle to the bone pin?

Joe, from the face to the center of the pinhole, it's about 10.5mm.

[jwscab]

thanks Marc,

can you also measure from the face of the plastic part all the way to the end of the bone, at the center of the pin? I'm looking for overall length. These could be cheap replacements for yokomo 870c universals that can convert over to pin and nut arrangement for 2.2" wheels, I just don't know the dimensions, and you happen to have them and can measure them

[Mr. ED]

mmmm didn't we have a loooong thread with all this info allready in it?
I remeber building an 870C with white arms just to proove it can be done.
I have to look for it , but I think I used 68mm lazer CVD's for the rear or front.
(Depending on how your front is made up you need different lentgh Yok universals also)

[jwscab]

yeah, we have gone around with this topic before. Just curious of the dimensions, since he can measure them easily at this point. I don't know if the dimensions were ever published.

[Coelacanth]

yeah, we have gone around with this topic before. Just curious of the dimensions, since he can measure them easily at this point. I don't know if the dimensions were ever published.

I'll get that spec for you probably tomorrow night, Joe. I probably won't be home tonight.

[jwscab]

no rush man, appreciate.....have a good night

[Mr. ED]

http://www.rc10talk.com/viewtopic.php?f=29&t=15474&hilit=lazer&start=30

68mm is good for the rear, but you need some wide offset hubcarriers: like the optima ones
The 73mm ones are good for the front if you have rear arms in the front
(All the above is for 870C = NOT for 91 and later works)

[Coelacanth]

Here's the finished idler pulley dust-cover I fabricated out of leftover Lexan pieces. The Weld-On worked great, the 3 pieces seemed to cement together very well.

PulleyCover3.jpg (21.88 KiB) Viewed 1732 times

PulleyCover3.jpg (21.88 KiB) Viewed 1732 times

PulleyCover4.jpg (46.82 KiB) Viewed 1732 times

PulleyCover4.jpg (46.82 KiB) Viewed 1732 times

After making a mess in the past trying to seal my Optimas' chain-guides with silicone, I thought I'd share a simple technique I used to do a more tidy job. I simply mask along the outer & inner edges where I'm planning to apply the silicone, and as soon as I've applied the silicone (I use Household Goop), I remove the tape, which results in some nice, clean lines instead of having silicone drooping over the edges, getting everywhere on your car, hands, etc.

[Coelacanth]

Here's a progress shot, I was able to get quite a bit done this afternoon.

[nvxwax]

Looks killer, cant wait to see it finished