CRT.5 build - would opinions on my setup choices - Page 2 - RC-Monster Forums

VintageMA · 08.30.2007, 03:29 PM

Good support from Horizon Hobby - they are arranging a RMA for the charger.

jhautz · 05:38 PM

Quote:

Originally Posted by VintageMA

JHAUTZ - I'll post some pics on this thread as I am building. A few questions for you if you've thought out some build issues.
1 - What are you going to be using for the battery mount? This is the one place my customization and craftmanship skills always struggle.
2 - Do you think I should get a UBEC as well for the 4S A123? I was going to try the BEC in the MM - but I know I've read a lot that the MM BEC gets hot even on 3S LiPo.

I typically just use some velocro on the chassis and the pack, then strap it down with a gorilla maxx strap. I havent had any issues with it yet. If it were lipo I would make some sort of box out of Carbon Fiber angle stock or aluminum or plastic to protect the cells more.

Yes, use a UBEC for sure. A cheapo will due just fine for this small truck. Just get a $15 one from one of the flyer websites.

Sorry for the delayed response. I didnt catch that you asked a question at the bottom of the post.

Quote:

Originally Posted by VintageMA

jhautz - What servo are you going to use. I picked up the HiTec HS-5245MG, but I've seen some threads on here about people overheating them with too large tires.

I've always had very good luck with HiTec digital servos, and I am planning on making the jump to 75MHz FM to DSM2 when the Spectrum DX3R radio comes out this fall - so I wanted something solid that I could run at a higher frame rate.

I'm using the same one. Just ordered it a few days ago. Should be here soon. On the plus side the CRT.5 showed up yesterday. (grin)

VintageMA · 08.30.2007, 10:37 PM

The buggy should hopefully arrive tomorrow for the weekend.

I guess I am still missing the UBEC - can you send a link to one?

Any idea what you are going to use for the diff fluid? I've been reading 3K f/3K c/ 1K r is a popular starting point - but I am wondering if it would be better to go go with the standard 3/7/1 used for buggies - I'm never sure where to start with that as I mostly just bash and don't race.

jhautz · 08.30.2007, 10:44 PM

Just look around. there are alot of places that sell em. Mike has a higher end one in his store.

VintageMA · 08.31.2007, 02:40 PM

Just got the CRt.5 in today - WOOHOO!!

Thought this was cool. I ordered it from A Main Hobbies and it came with a 2nd set of wheels :)

Let the fun begin.

BrianG · 08.31.2007, 04:02 PM

Yeah, mine did too. They have different hub mounting so watch out before you glue the tires on there!

jhautz · 08.31.2007, 05:27 PM

Quote:

Originally Posted by BrianG

Yeah, mine did too. They have different hub mounting so watch out before you glue the tires on there!

Different hub mounting????

What do you mean? I thought it was like the Losi or AE cross pin style.

BrianG · 08.31.2007, 06:21 PM

One set is the cross-pin style, the other uses the hex hubs...

VintageMA · 09.04.2007, 10:44 AM

Yeah - I see that - that's kinda a pain in the butt with different types of wheels - I can't really see using the ones with the cross-pins.

Probably going to put all the nitro stuff that came in the kit up for sale on e-bay (just the muffler piece alone is $50 online) so that'll make up for some of the expense on other parts.

Here's a few pics of what I've done so far. The motor mount isn't great (just some L-arms from Home Depot cut to fit along with velcro tape and velcro straps - but seems to be holding well for some trial runs) - I just don't have the tools or the skilz to do some of the sweet work some of the guys here do.

Buggy seems to be running okay. A few initial thoughts
- the shocks seem very soft, I wonder where I can get some replacements that are a little firmer and the right size.
- I started with a 13T pinion and the motor was running pretty warm but the ESC was cool - I'll try to gear up a little to even that out.
-max Amp draw was recording right about 50A using a 3S lipo pack (still haven't gotten the replacement A123 charger yet)
- I need an antenna mount because it's just hanging loose right now

Pluses - I am very impressed with this buggy for $250. I could easily see this little guy put my LST2 on the shelf for a while.

With Mike's motor mount the whole project was made very easy.

I want to use a plastic spur gear - but I think I'll wait to see if Mike ever has one just for this buggy - I don't want to drill too many holes in the chasis.

VintageMA · 09.04.2007, 10:48 AM

Oh yeah - one more complaint (or whine) is that with the motor mount and servo setup it is impossible to change a pinion w/o first either removing the servo or removing the whole center diff assembly.

You just can't get to the bottom screw with the servo in the way.

BrianG · 09.04.2007, 12:52 PM

Quote:

Originally Posted by VintageMA

Oh yeah - one more complaint (or whine) is that with the motor mount and servo setup it is impossible to change a pinion w/o first either removing the servo or removing the whole center diff assembly.

You just can't get to the bottom screw with the servo in the way.

Yeah, that does suck. I thought about making some sort of quick-release for the servo since that would probably be easier to remove quickly than the CD.

VintageMA · 09.04.2007, 01:14 PM

Just fyi - I meant to say BATTERY mount. Mike's motor mount rocks!

"Here's a few pics of what I've done so far. The motor mount isn't great (just some L-arms from Home Depot cut to fit along with velcro tape and velcro straps - but seems to be holding well for some trial runs) - I just don't have the tools or the skilz to do some of the sweet work some of the guys here do."

jnev · 09.04.2007, 07:49 PM

It looks great!! Nice job on it! What Hacker motor are you running in there?

VintageMA · 09.04.2007, 08:35 PM

Quote:

Originally Posted by jnev

It looks great!! Nice job on it! What Hacker motor are you running in there?

Hey, thanks. It is a Hacker B50 8L (3019kv) motor. Very solid, in my opinion not quite worth the money ($180) but I already had the MM esc. I would place it somewhere halfway between a Feiago and a LMT/Neu. Strong power, but you can feel the pull much more when you use a LMT.

Still a lot of tweaking to do........ but that's just part of the fun.

09.04.2007, 10:34 PM

Looks good! The crt.5 is a great truggy to convert, you will love it.

Its funny how much different my crt.5 looks than others. With the ext. chassis, 1/10 2.2 rims+ tires, full size servo and larger wing+ body its a completely different truggy. I really need to post up a thread of my own, just waiting for the new lipo to arrive (TrueRc 4s 4.2Ah custom pack).

Bye