CAT SWB

[winner_evo]

Hi all,

really happy to have found this:




Looks all original (maybe a later rear shock tower), still has the front one-way and missing only the front & rear ARB's.

Needs a good clean, body needs replacing so I've ordered a repro item. The front crashback pivot pins are too short so I'll make some new ones and the steering bellcrank needs adjusting.

I'm not sure if the rear diff is working correctly so I'll have to look into that.

No idea what the speed controller is, anyone have an idea? I've removed all the electrics anyway so maybe I'll post some pics of the esc in the other section.

Anyone have a good scan of the original manual I could print off?

I'll do some work on this when time permits...

[XLR8]

Very cool indeed. These are becoming extremely rare. I still have one but it's in pieces at the moment.
It's a shame what PO did to the body; perhaps he didn't fully appreciate what he had. Can it be stripped?
Here's a manual - unable to confirm publication date but it does show the one-ways and first generation front pivot bracket (T006) so it's early:
http://www.competitionx.com/pdf/vehicle-manuals/schumacher/schumacher-cat-manual.pdf
It would be awesome if you would post a full rebuild here.

[winner_evo]

Indeed these are pretty hard to come by as I've been looking for a while. Unfortunately the body has had the sides at the rear cut away and quite a bit at the front too so i don't think it's worth trying to salvage.

Thanks for link, very handy I did find another decent quality manual with the XL stuff in too.

If you're interested then I'll certainly post up the progress, I've removed the undertray, chassis & topdeck today for cleaning so I'll take some pics as I go along.

The plan is to replicate my old racer so I'll need to find some old of the original electrickery I used back then (86-88).

[winner_evo]

Stripped and cleaned this lot. So far all the screws are correct, the undertray wasn't fitted correctly, hole positions were out or missing altogether and it wasn't cut out very well, same goes for the upper belt cover.



I'm going to need to buy some of the ARB parts, I'll shape the rear one and use the re-re front one.

[DennisM]

Very nice SWB You´ve found.
Can´t have been used much.

Can You post some closeup pictures of the ESC?

[winner_evo]

Yeah, it's not showing much wear and nothing hacked or missing, quite a lucky find I think.

The speedo I've since found out is a Demon 2DH from 1984'ish, so a pre FET Demon. I've powered it up and it seems to work but not sure about the brake.

Here's a pic of it:





I ran a Demon King esc in 86 or 87 but I'd never seen a 2DH.

[winner_evo]

I thought I'd take the spur gear off to see if I could see any reason why the diff wasn't working correctly, here's why

The rear thrust washer carrier didn't seem to want to come off the spur gear....






Looks like it they melted together, I bought a NOS spur gear the other day mainly because the edge of the teeth were worn.

[XLR8]

Unfortunate but probably not completely unexpected. These early Cats have two, somewhat redundant, ball diff assemblies (in the spur and the integrator) and it's difficult to get both spinning smoothly and with light resistance. Maybe the previous owner kept backing off the tension on the spur diff to improve differential action and went a little too light allowing it to slip. Of course, if he had loosened the tension on the integrator, he might have lost drive to the front wheels. Anyway, your lucky to find an NOS 32dp gear since I think the rere gear is 48dp.

BTW, that's one of the oddest ESCs I have ever seen. Almost looks home-made. Obviously well-made since it still works.

[winner_evo]

Yeah, the nut wasn't very tight when I removed it, the centre of the spur is starting to detach too. I was in two minds whether to buy the new spur gear, glad I did. I found it here in the UK but curiously it has a Japanese price tag on the packet, ¥ 550.

I'd not seen those earlier Demon esc's either, I only saw a picture of the esc from the top and thought the aluminium heat sinks might have been owner added for some type of bracketry

To be honest, the later Demon King FET esc that I had also looked a bit homemade, using the same blue heatshrink with the FET's poking through, but that was a pretty good esc and a noticeable improvement in performance and price over the Futaba esc I originally used.

I'd really like to find a Demon King for this car.

[winner_evo]

A bomb has gone off



So it's stripped, only a couple of issues found in total.

All the diff balls were clean & no signs of lube, the belt has cut through the front gearbox housing - this is still usable but I might replace it. Most of the ballstuds were loose in the hubs so I've threadlocked those. That's really about it, everything else looks good, I'll have to see how all the belts tension up.

I've used the thrust washer carrier from my leftover XLS kit diff so just need the spur gear to turn up.

Everything cleaned, just the shocks left to do before assembly.

[XLR8]

Could that damaged front housing be the result of an ill-tracking belt? I don't recall if it's mentioned in any of the manuals but, after a rebuild, I'd always leave the front belt tension screws slightly loose, power-up the car and run it on the stand at low speed to check the belt tracking. If the tracking was off center, I'd tweak the housing slightly left or right until the belt would track in the center of the pulley then tighten the screws. It's tricky to get the tracking right; the pulleys don't have fences, are barrel shaped, and the belt is free to wonder off center if tracking is ignored.

[winner_evo]

Yeah, it's certainly drifted off to the left, the cause I'll have to check. It may just be incorrect belt tension, tight integrator, melted spur or combination of all three.

I'll check once it's together and all lubed and adjusted correctly. I haven't seen anything in the manual regarding belt tracking but will keep in mind what you've mentioned.

[winner_evo]

The NIP spur gear turned up...




So I've lubed all the diff parts, fitted a re-re front anti-rollbar, trimmed up the original belt cover & undertray a bit better and started assemebly. Diff is now working






More to follow.......

[XLR8]

Wow, that looks like a new build.
I'm always amazed at how well these old Cats clean up -- the parts really don't seem to show age or use. My old XLS has countless runs and when I pulled it apart a couple years ago, the only parts that show any wear are the metal crosses in the universals.
You're going to have a really nice car when it's completed.

[winner_evo]

For sure, these old CAT's are pretty robust, I don't remember breaking much in my racing days apart from the front bumper. I think the wraparound body/undertray helps a lot.

Anyway, I have a roller....






Haven't had to purchase much to get to this stage:

Repro body & wing
XLS front ARB.
ARB ball stud ends
ARB ball cups
Length of M3 studding
1.8mm stainless wire for rear ARB (free)
1.6mm stainless wire for wing mount (free - still have to bend this)
Original spur gear
Schumacher O-rings
Schumacher nylon washers (still waiting for those)

More to do as and when I can.