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Re: Marui Galaxy Rebuild
Posted: Wed Nov 17, 2010 2:43 am
by Coelacanth
Here's a simple mod I did to beef up the Galaxy's steering linkage. The stock linkage uses piddly 1.5mm threaded rods which--as you can see--obviously don't hold up to much abuse. A few curb hits and they bend very easily. I had some 3mm threaded steel rod lying around and some leftover 4.8mm ball ends/cups, so I enlarged the holes in the servo saver and bolted on the ball ends & cups. The steering knuckles will also get 4.8mm ball ends installed and this Galaxy won't wilt as easily after minor bumps & bruises.

Re: Marui Galaxy Rebuild
Posted: Wed Nov 17, 2010 4:08 am
by peetbee
Cool, you should lose a lot of slop with that mod too.
The bent end in the servo saver was always hopeless.
Re: Marui Galaxy Rebuild
Posted: Fri Nov 19, 2010 1:50 am
by Coelacanth
I finished the steering linkage tonight. Reamed out the knuckles for some larger 3mm-threaded 4.8mm balls. I had to file off some plastic from the right side of the plastic bath-tub as the larger ball-cups would catch on the edge when steering left/right. You can see the rounded area I opened up just where the driver's side tie-rod & ball-cup emerge from the chassis.
It seems to work great, with absolutely no slop.
Re: Marui Galaxy Rebuild
Posted: Fri Nov 19, 2010 4:22 am
by pattywagon34
very nice.cant wait to see it when its done.
keep up the work
Re: Marui Galaxy Rebuild
Posted: Fri Nov 26, 2010 11:09 pm
by Coelacanth
I managed to track down some new blue plastic parts for $5 and a set of 3 new chassis covers for $8, both items from a local seller that has a veritable stock-pile of vintage Marui parts. Turns out he bought out a local hobby store's parts when they closed, but (perhaps unfortunately) it's almost all Marui. Unfortunately he didn't have a new roll-cage...
When I originally built the car, I never installed a front stabilizer, because the kit didn't include piano wire, and that was what was required to make the stabilizer. (I remember searching in vain for the piano wire in the kit, and couldn't believe it wasn't included!) Anyway, these days, I have piano wire for wing stays, so I measured & bent an appropriate piece. For the first time, this Galaxy has a stabilizer!
The shock spring cups I bought previously that were too small for Kyosho Gold-style shocks turned out to be a good fit for the older Kyosho red shock springs. The shock ends fit a bit loose but not enough to worry about.
Rear suspension re-engineered
Posted: Sat Dec 04, 2010 8:20 pm
by Coelacanth
The Galaxy's stock rear suspension absolutely blows chunks. I must say the car was extremely badly designed!

It doesn't work well with the stock parts, and the design is such that modding it to make it work better was a major challenge. The biggest issue is probably the bigger shock bodies obstructing the movement of the rear control arms. The Galaxy's design is pretty primitive, with no way to adjust camber. This means that the tops of the rear tires can bump into the shock springs and spring adjuster because they swing inwards as they move upward with maximum compression. Improving the suspension on this buggy proves to be a helluva lot more challenging than simply upgrading the shocks!
I must've spent all day trying to figure this out, first trying to mount the shocks behind the towers instead of in front, but even though I got the obstructions resolved, the shocks were binding because they were located too far behind the axles, I think. The Galaxy absolutely needs to have the shock bottoms located in the stock positions in order for the suspension to have a remote chance of working properly.
Well, I finally figured out how to get the suspension working well, but it meant totally re-engineering this plastic craptastic car. I removed chunks of plastic from the trailing edge of the control arm, and the leading half of the black shock tower brace. This allowed me to keep the suspension travel moving more or less smoothly and without the shock body being an obstruction. I fabricated a shock tower from a piece cut out of a spare beat-up Optima upper deck and an hour of hack-sawing, Dremeling, filing & drilling. One benefit is that it's stronger and much stiffer than the overly flexible blue plastic shock towers. I believe that flex was contributing to the binding.
The shocks are 3racing 54.5mm shocks, which are new, and almost the perfect length to match the originals. The bottoms are 4.8mm balls & cups. I got one side done and let me say this, it works WAYYY better than stock!

Re: Marui Galaxy Rebuild
Posted: Sat Dec 04, 2010 11:12 pm
by SFC K
This is a really nice build! So did I read that right, your giving this back to your Brother?
Re: Marui Galaxy Rebuild
Posted: Sun Dec 05, 2010 1:05 am
by Coelacanth
SFC K wrote:This is a really nice build! So did I read that right, your giving this back to your Brother?
Yep, it was his to begin with, but the "upgrading" will be my gift to him for his birthday. He'll hardly recognize it when it's finished!
I got the rear suspension done tonight. I made a template of the completed right shock tower and carefully duplicated it. When fully compressed, the tires ALMOST touch the shocks/springs. Very close! I must say these 3racing shocks are quite nice for about $20 for a 4-pack. I needed to open up the 2 holes in the pistons and switched to 25-weight oil as they tend to be quite stiff. They're probably perfect out-of-the-box for an on-road/touring car, but too stiff for off-road use.
Posted: Thu Dec 09, 2010 10:30 pm
by Coelacanth
I pretty much completed the chassis rebuild. The front shocks were easier to upgrade than the rears, fortunately. I went with the narrower Kyosho Optima front shock springs, which fit the spring retainers and just fit over the threaded part of the shock bodies. Because they were narrower, there turned out to be no rubbing against the upper half of the control arms. They don't absorb as nicely as I'd like, even with 25-weight oil and opening up the piston holes, perhaps because the car is so light, with all the plastic and such...but they definitely work, and work a lot better than the stock pieces of crap--which were not much better than Tamiya Grasshopper or Hornet shocks.
I added a set of Academy GV2 front wheels, generously donated by
tsan (thanks, man!), and some Tamiya tires that I picked up for $5 from the guy that sold me the Marui parts. The GV2 wheels needed 5 x 10mm bearings, fortunately I had a bunch of leftover Optima bearings.
Lastly, I reassembled the differential gearbox. I'm impressed with the progress thus far, it's no RC10 but now, it's a long ways from a stock Galaxy/Hunter. My bro is probably gonna crap his drawers!

Re: Marui Galaxy Rebuild
Posted: Fri Dec 10, 2010 8:45 am
by tim.sanderson
Good job! That looks really slick. I'm glad the wheels worked out for you.

Re: Marui Galaxy Rebuild
Posted: Fri Dec 10, 2010 9:24 am
by peetbee
Looking fantastic, I wish mine had been as good as that when I ran it all those years ago!
In your picture "RearSuspDone2.JPG" you can see the gear shaft that I was talking about. This is what allowed the gears to strip on mine as it's a bit too free. Although the hole in your motor mount that it passes through doesn't look too worn so it may be ok. I'd just check it carefully before running

Re: Marui Galaxy Rebuild
Posted: Sun Dec 12, 2010 11:55 pm
by Coelacanth
I re-soldered everything on a Kyosho Le Mans 360ST endbell after giving the motor a good spraying with Easy-Off followed by compressed air. New capacitors, springs & brushes, motor leads & 3.5mm gold connectors were installed, and a 16T pinion gear. Now I just need to wait for an ESC to arrive and I'll be able to test-drive this car. It should be a significant performance boost over the stock Mabuchi 540 can.
Re: Marui Galaxy Rebuild
Posted: Mon Dec 13, 2010 10:36 am
by Coelacanth
peetbee wrote:In your picture "RearSuspDone2.JPG" you can see the gear shaft that I was talking about. This is what allowed the gears to strip on mine as it's a bit too free. Although the hole in your motor mount that it passes through doesn't look too worn so it may be ok. I'd just check it carefully before running

I see what you're talking about...the shaft seems to be pretty secure. I suppose it wouldn't be too difficult to bolt a piece of metal or something across the shaft, keeping it in place should it ever come loose and pop up.
What I noticed mounting the 360ST with the smaller 16T pinion gear is that the motor had to be pressed pretty much all the way down to the bottom of its adjustment slot to mesh properly. The car originally came with 3 pinions: 18T, 20T and 22T, but I thought it might be wise to reduce the ratio with the higher-revving 360ST and bigger-diameter rear tires. I won't be able to tell without a test run--I have to wait on an ESC to arrive.

Re: Marui Galaxy Rebuild
Posted: Tue Dec 14, 2010 12:19 am
by Coelacanth
Here's a different look, with some Carson wheels I just received from nvxwax and a set of Traxxas front spiked tires. The rears are a second pair of vintage You-G tires I had in storage for 2-and-a-half decades. I think the black spoked wheels look better than the white dishes...what do you guys think?
Re: Marui Galaxy Rebuild
Posted: Tue Dec 14, 2010 3:07 pm
by Mr. ED
got to see it with the cage on to make up my mind. How did you end up doing the rear wheelconversion?