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DennisM wrote:I think You mean 4mm washers Marc?

I could've swore they were 5mm holes...I'll have to check what I used for Barney. They're pretty big, 14mm or something O.D. I'm using Axial Rockster wheels on that car, and the axle holes are 6mm at least...too big for the axles I'm using with the CVDs on that car. Bear in mind that the Lazer CVDs have 5mm straight axles with cross-pins, not tapered. I'll be able to confirm tonight probably.

About the hub size difference. I was thinking about that and decided a nut with a built in hub on it would be perfect. Now I just have to find one that will work. Wish me luck. If not I'll just make some adapters. Might be a good project to use a lathe on.

And about the radio. TamiyaDan what you suggested made good sense. No point in trying to cobble together the old and new radio and ESC. Connectors were going to be different and while I'm sure it would work eventually it seemed like a potential spot for problems down the road. Plus I have another thrasher (Tamiya Hornet and parts car) that could be put together for my sons friends to use when they're over.

I went ahead and ordered a Futaba 3PL, R2004GF receiver and a S3470SV servo. Had a couple hundred dollars in gift cards for Amazon sitting around so that seemed like a good use for them.

Again thanks for the ideas, sensible opinions and wealth of information shared so far.

It looks like I had a bunch of parts show up the last couple days but I'm out of town with work till Sunday. So I might be starting re-assembly early next week if all goes well.

Greg

Well I finished up my work early today and drove back from Charlotte today.

I decided to assemble the wheels tires and see how they looked. I like them.


The tires are a little narrow for the wheels but not unusably so. I knew this going in as I could have purchased wider tires
but I wanted to see what the effect would be. Again I like it. Might not be for everyone but that's okay.


And here they are all assembled.


So I will begin assembling the diffs on Monday. I'm thinking I'll hold off on the anodizing for now until I can confirm the color I want to get.
The green (if it's not green let me know I'm mildly color blind) of the wheel centers looks good to me so I'm going to see if I can get that replicated.
If so I'll do another tear down and get the aluminum parts done that color.

I must say this rebuild has been a lot of fun. I'm excited to get this thing done and driving. Just a few more weeks I hope.

I´d call that colour titanium - Have You seen the different colours Pargu has to offer?

Titanium. I can see that. Thanks. I've been on the Pargu website but didn't really come across a color chart.
I did see a basic picture of a lot parts in different colors. There is certainly a broad range to choose from.

As far as the anodizing goes I have a friend here locally who owns a metal finishing company. They do anodizing amongst other things.
When I get a plan together I'll contact him and see if:
A. He's willing to do such a small batch.
B. He can do the color I want.

So today I started putting the bearings in the hubs and reassembling the diffs. I noticed with the drive hubs on there is a fair amount of endplay in the hubs.
I'm thinking I need to determine how much with a feeler gauge and get some shims to tighten a little.

Next question. When using bearings in the center gear what have you guys used to keep them in place? I'd imagine a sleeve of some sort on the
center gear shaft. Or is this one of those times where I didn't do enough homework up front and I was supposed to get flanged bearings for those?
I've found a source for a spacer (4.2mm ID, 6mm OD) in varying lengths made from either aluminum or nylon. Thinking I'll go that route.
The question is, what is the diameter of the center gear shaft? I really need to get a new battery for my caliper. Haha.

Once I get some more progress behind me I'll post some re-assembly pictures.

The centergear shaft is 4mm.

Flanged bearings is the way to - otherwise, You´ll need washers on both sides. BIG washers.

Buy 10 flanged bearings - that way You´ll have this and the next four optima builds covered.

The original Optima with the bushings had a bushing collar or something that you stuck inside the hole, sandwiched between the normal bushings or bearings, keeping them in place. With flanged bearings, there's no need for that collar and they work perfectly. Regarding the axle hole size issue, I noticed that your wheels don't have a recess on the outside that would keep a 14mm cone washer in place, like the Axial Rockster wheels I mounted with the Barney car. What you could use is a barrel nut, probably the shortest one you can find.

Something like this; RC4WD.com has a few lengths to choose from, and you will find more on eBay:

http://store.rc4wd.com/1x-M4-x-8mm-Barrel-Nut_p_513.html

You'll need to do some careful measurements to make sure the barrel length is enough to snug down the wheel onto the axle threads.

EDIT: That wheel & tire combo looks great...I'll have to look into a set of those.

Thanks for the good advice Dennis. Yes I found a set of 10 going to order soon.

And Ceolacanth, as usual, thanks for the link. While that is the closest thing I've found there is another issue that needs to be addressed.
Also I did go ahead and get the 3Racing shocks for the Tamiya DT-02. We'll see how they work out. Thanks for the recommendation.

The drive hub on the wheels is a little too deep for the optima drive nuts and rubs on the knuckle. But I have a solution. I'm not at liberty to share it yet.
Not because I'm unwilling or wont share it, I just want to make it first. So be patient and I'll hopefully have something to show soon.

Next up my new radio showed up today. I was shocked at how much smaller the receiver is than on my old setups.

Also my Brushless motor and ESC showed up. Again that ESC is tiny compared to the older ones I've seen.

And next, btw today was an amazing day for some reason, I stumbled across this.


Like literally it fell into my lap. Here is everything it came with.


Yes that is a mostly complete set of original stickers.


It's currently very close to being a driver and I'll get it running for the time being. So that will a later project.
Question. Did the Turbo Optima Mid have universals in the front halfshafts? This one does but I don't know if that is stock or not.

For now I'm focusing on the original build.
Still waiting on some ebay items (sellers can be so frustrating sometimes)

Also on the issue of hub end play. I measured the endplay in between the drive nuts and hub bearings and it was .016" or .406mm.
I have sourced some shims in .015 thickness to fit between the bearing face and drive nut. Is the clearance there needed for a reason?
To me it just makes the front end feel sloppy and I want to eliminate that.

I am also working on a solution to the mounting of the steering servo. You see my opinion of mounting the steering servo with double
sided tape is not good. Sure it works but it's not secure and in my experience doesn't last long. So you end up having a sloppy steering
setup that is prone to malfunction. Considering that I purchased a steering servo with over 100 oz-in I have decided that a more secure
mounting arrangement was required. Again I have an idea that I'll share once completed.

So yeah today has been a day. Sorry for the rambling disjointed post. Lots going on.

BoostCreep wrote:The drive hub on the wheels is a little too deep for the optima drive nuts and rubs on the knuckle. But I have a solution. I'm not at liberty to share it yet.
Not because I'm unwilling or wont share it, I just want to make it first. So be patient and I'll hopefully have something to show soon.

Your wheel centers are aluminum, so that'll be a bit more of a challenge than with the Axial Rocksters, which have plastic centers. Those also have very deep drive hubs and I also had rubbing issues with the bearing carriers, but it was an easy fix to carefully round out the inner edges of the plastic with a Dremel tool and rounded grinding cone...the bit that's shaped like a bullet. I took off a wheel and took some better pictures.

Thanks for the pictures. I had considered milling down the drive hubs so they would clear but decided against it.
I would like to get some nylon or delrin washers for the rim face to prevent scarring from the retaining nut.

About a year ago I traded a trailer I no longer used for this.


I haven't even moved it to my shop yet but now I have a reason to do so. I also need to get a chuck and some tooling.
I used to have a lathe 15 years ago but had to let it go during a move and don't have much of the tooling left. What I do
have probably won't fit too well as it was a different animal.

So the plan is to fabricate my solution to this problem. We'll see how it turns out. (Pun intended)

BoostCreep wrote:Thanks for the pictures. I had considered milling down the drive hubs so they would clear but decided against it.

Awesome, wish I had machinery like that!

Milling down the hubs would be perfect...you can also buy thicker drive hexes. In addition to the ones that come included with the Optima, Kyosho made a thicker and thinner set of hexes. I have both of those sizes, I'm actually using the thin hexes with CYANide to narrow the track width so that the wheels & tires would more closely fit the HPI body.

How about cutting out some little round disks from some leftover Lexan to use as wheel surface protectors?

So the plan is to fabricate my solution to this problem. We'll see how it turns out. (Pun intended)

Looking forward to it...make extras, I might be interested in some.

.

Just a little thing on the Optima driveline.


The following is written by traffman in an Oople thread:

"I stretched my chain back in the day with a set of 1400 scrs and a 17 double!
God knows what brushless would do."


The following is written by Terry.sc in the same Oople thread:

"For a belt drive conversion the expensive option is to get hold of the Option House conversion kit which are ridiculously overpriced.

The cheap way is to just take the diff cases and belt out of a used short wheelbase Mid and sell the rest of the parts off, the rest of the buggy wears out before the belt drive does. Just swap the belt and diff cases over. The full conversion includes a small pulley to take up the small amount of slack in the belt, but it isn't necessary.

Also don't bother spending a fortune on a hard final pinion, use the Ultima plastic final pinion. You need the pinion and counter gears from the UM-1 Ultima gear set and the layshaft from UM-5 gear shaft set.

My bashing Optima has been running with these setups for years with a 13 turn brushed motor in it"


My runners are belt driven

I kept my Zebra Optima pretty much stock, with the exception of adding any gold part I could find. But all my modded Optimas are belt-driven too.

I believe the cheapest solution to the hard final pinion gear is to get the Robinson Racing 19T motor pinion gear and a few spacers. Somebody on here made a topic about it and confirmed that it would work...and the gear costs about $5 bucks. If I didn't have a few spares already, that's the route I'd take. No way in hell I'm gonna spend $30+ for a frickin' gear.

Thanks all for the advice and sharing your past experiences. I know the brushless will have the ability to shred the driveline. I'm hoping/going to try and adjust the accel parameters to make it softer on tip in. We'll see if I'm successful or not.

Had some parts show up yesterday. Mostly just spares. Basically a complete rear gearbox. Also some spare shocks (original Optima) and an extra chain. One part I didn't have was the gearbox cover so now that's in hand too. Progress however small but progress it is.