Scale-ish Tlt Size Crawler Build Up Thread

[Petrolhead]

I fancied a change from the normal buggies / touring cars so decided I wanted to build a scalish crawler. First decision was that it would be TLT size, rather than clod, as this should keep costs down.

Did a bit of research and with the help of Twinset I came across a chassis that seemed to be just what I was after, the MFM Racing Scale Chassis. This had just the right balance of scale-ness that I was after. So I ordered that and a few other key parts - Moabs, RPM Revolver Narrow Rims, the MFM tranny mount plate, a high torque servo, some ball-ends and a few other bits and bobs from The Crawler Store, who I can't fault. Delivery was pretty quick and got here in time for Xmas. I also bought 2 TLT axles, complete with 'bling' and a brand new Stampede gearbox from Mr_Pushrod, cheers Alan!

So set to building it yesterday. First thing I had to do was lock the diff in the 'Pede tranny. I've seen a few ways people do this, all involving some sort of sticky gunk and are irreversible. I came across THIS WAY of doing it, which involves two small nuts and a tiny bit of filing. A great, simple, costless way of doing it, and it's locked great.

Next job was the fit the MFM Tranny Mount Plate onto the Stampede gearbox. The plate has 4 counter-sunk holes which line up with 4 holes in the gearbox. However, there was a raised bit on each side of the 4 holes meaning the 4 screws wouldnt reach and the hole either side of the plate to mount it to the chassis was blocked. I could have moved the plate down so the top two holes were mounted in the bottom two, but this meant the gear box was up too high and it wasnt mounted as securely. So, out came the hacksaw and I cut off the raised bits. I wouldnt need this so it was no big deal. You can see in the pictures the parts I have cut off.

The plate finally mounted securely, after cutting:

In my opinion, the 'box is still too high but it can't go any lower as it will rub on the chassis, so I'll have to live with it and maybe stick some lead in the tyres!

Next up was mounting it to the chassis. This was no problem, just bolted it on with 2 M4 size bolts. However, when I came to put on the two middle cylindrical chassis braces, one of them wouldnt quite work in the place it is meant to as it would catch on the driveshaft. So I simply moved it along to another hole.

Correct brace mounting:

Different position brace mounting:

Motor wise, for the time being Im using the Graupner Speed 600 I used in my XC. This has great torque, even better with the added torque ring.

Next up was locking the steering on one of the axles. I did this by using two ball ends, one connected to the steering and one attached to the axle and joined them together. I did this by cutting the head off an M3 screw and screwing it into both of them. This saved my tapping out both ball ends and using some M4 studding.

That done, I put the wheels and tyres on. For the time being Ive left the foam in them, but Ill see if I prefer them without once Ive got it running.

Heres a mock-up shot of what it should roughly look like when done. What Im waiting on now are shocks and the Traxxas slider driveshafts.

Thats all for now. Next up-date when I get some more bits to continue.

[Wrc action]

Very cool - Im using Tlt axles in my latest dakar support truck and will probably use the same way of locking the rear axles steering.

How are you doing your steering? servo in the chassis or on the axle? as im undecided at the moment on which way to go with mine.

Also what size are those tyres and where did they come from?

Cheers Ryck

[Petrolhead]

Cheers for the response Ryck. Steering wise, I'm going to stick it on the axle; I've already got a mount plate so it saves a lot of hassle. The tyres are Proline Moab M2 Compounds, 2.2 size. I got them from TheCrawlerStore, but they're quite commonly available.

[Wrc action]

no problem allie - I know its nice to get some feedback when u spend all that time writing up a post.

i think that probably what I am going to do, Just a little warry of having the servo so exposed to water, sand and all the other elements. are you planning to protect it in any way?

what Im building is this http://www.tamiyaclub.com/forum/index.php?...20&start=20 shown at the end I am now using a highlift based chassis with tlt axles over the old xc chassis for reasons shown in the thread.

do u think your tyres would fit? in those arches? the ones on there and highlift tyres.

cheers Ryck

[secretasianman]

nice work so far, but i'm wondering : Was there any reason the diff in the tranny was locked? I understand there are benefits to locking the diffs in the axles, but I was under the impression that the tranny with a diff used as a torque splitter was more ideal.

Also, you might want to remove the guard on the front axle if you have any plans to crawl. I know it doesn't protrude as much as a Juggernaut or TXT steering box but removing it increases approach options and every little bit counts.

[Petrolhead]

Reasons the diff in the tranny was locked - for example, if it wasn't locked, if one axle was spinning and the other wasn't, it would send the power to the axle that is spinning, meaning the gripping axle wouldn't get as much/any power and it wouldn't make any progress.

Yup, the guards are coming off the axles soon, thanks.

[secretasianman]

oh gotcha, I looked around and it's a planetary gear diff. definitely won't do what I expect unless it had balls. (ball diff I mean)

[Wrc action]

Ooo any chance of those gaurd being posted up to little old pershore then allie?

As Im not doing any crawling and I think they would definately improve my machines survival chances on the run.

good Job Im going for a straight fwd 3 speed no trannys to lock both ends get the same power and both diffs where locked when I got them

How does a TLT axles lock? as I havent even taken them apart yet :L

cheers Ryck

[ryanbored]

OMG this is spooky- I've just ordered nearly the same bits, but making my own Chassis for a 6x6 Unimog thingy (Be prepared for an "unfinished project listing on ebay soon!!)

[Petrolhead]

Body-wise I'm looking at a Proline Chevy C10. If anyone knows the dimensions / has one and can measure it for me, that would be much appreciated. The specifics I'm interested in are the length and wheelbase.

This is the one I'm on about:

Also, I've got a high torque MG645 servo. It says it can be used in boats, but I don't think it's waterproof. Anyone shed any more light?

Ta!

[secretasianman]

HT metal 645 's are good, I run a pair on my juggernaut crawler and have no trouble turning the big rubbers standing on carpet. It should have no problems steering a smaller car.

[Petrolhead]

Thanks, I've heard good things about them. Are they waterproof though?

[Petrolhead]

I bit of an update...

I got the body from Modelsport on Sat, a Proline Chevy C10, meaning I could set the wheelbase and ground clearance and get on with making the links. To do that I used Twinset's how-to guide, and most helpful it was. First thing to do though was to relocate the link mounts from underneath the axle to on the middle-facing side. This meant, however, I had to take off the axles braces that the axles had on already. This meant undoing 24 nuts and bolts, gripping the bolt with pliers in one hand and turning the bolt with a screwdriver in the other, not a fun process.

Anyway, those off I put the link mounts in their new position. This meant a little of of axle-shaving was needed as there was a ridge in between the two bolt holes. So out came the files and 5 minutes later it was sorted. With link mounts in their new position I could measure how long I wanted to make the links. First pair for the rear axle turned out a bit long, no worries I though, I'll make the front ones a bit shorter by the same amount. The front pair turned out a bit long too, so I had to go back and cut them down a bit. Now the rear links are a bit longer than the front, no biggie.

I also moved the front steering link to above the knuckle, for better approach angle. And I got rid of those pointless bumpers; Ryck, they're all yours!

Here are the pics. The chassis won't be as high up as it is seen here, but the phone was handy and wasn't too far off. Took me a while to get the chassis balanced on it, and when I did, the phone rang Obviously the body will be raised up off the tyres too, only after it's undergone some major lexan surgery.

[Wrc action]

Thats superb work there allie. And looks much better than I was expecting with regards the shell.

Yay! cheers for those parts Ill pick them up at the bash if u dnt mind, save on postage. Should hopefully protect my axles and steering from a heavy beating when it on the fast sections.

Cheers

Ryck

[Petrolhead]

Cheers Ryck. And no worries on the bumpers.

The shell has undergone some major surgery so that the tyres will hopefully not rub when flexing. I've also put the shocks on and re-located the rear link mounts. I'll get some pics up asap.

I got the shocks for an absolute bargain. 10 inc P+P for 4 of them off eBay, they're Traxxas oil ones originally for the T/E-maxx

[Petrolhead]

Ok, so next lot of pics...

First up the new rear shock and link mounting position. This little bracket does both in one, whereas I was using 2 seperate brackets before. I've now got a couple spare to play around with. The rear shock mounting was pretty simple, although they do rub on the tyres still when at full flex.

The front shock mounting was more tricky. I couldn't mount them anywhere outside of the chassis as I'd get major rubbage when flexing whether the steering was turned or not. And even when not flexed they rubbed a bit. So I had to mount them inside the chassis. Unfortunately the springs catch on the edge of the rails a bit, but I can't push them in towards the middle any more.

Still, it works pretty well at the moment. This is without the final links attached, though.

And the pics of the body hackage - I went all out on the back but need to do a bit more on the front. I brought the sides up too, it looked silly with them hanging lower.

Obviosuly the body will be higher and at a flatter angle, I haven't got round to doing the mounts yet.

For now.

[Wrc action]

Hi Allie

Looking superb and I can see the big cuts that u have had to make to the back of the shell like u said on msn.

Do traxxas do smaller versions of those shocks? Also those brackets, are you making them or did u buy them from a supplier?

Cheers

Ryck

[Petrolhead]

Cheers again Ryck.

Can't help you with the shocks I'm afraid, to me the ones I've got seem like normal buggy/truck size shocks.

The brackets come with the TLT kit as they are used on the axle casing, hence why I already had them.

[Petrolhead]

Ok so pretty much done now, all I need to finish it off is to paint the bod. Anyway - last few build up shots here...

Thanks to Twinset for the servo/link mount plates, they're super. Also got the sliders from Modelsport, meaning I could get on with making the upper links.

As I had the driveshafts, one thing I noticed was that, as I couldn't run any caster on the front axle due to the fact it would mess the steering up, then there would be some horrid driveshaft angles. So I swapped the links around, now I've got the longer ones at the front and shorter ones at the rear. Means the front axles a bit further forward = better weight distribution = good! So I made up the links, running a good bit of caster on the shorter spaces rear axle to get a better 'shaft angle, and no caster on the front but it doesn't need it.

Twinset's plate:

Once that was done, all I had to do was extend one driveshaft...

... and bung the eleccies in. I struggled to find somewhere to mount them low down where all the wires reached so I settle for a temp solution of mounting them in a tray up top. Very pleased with the servo too - it'll turn the wheels whilst not moving on carpet with ease, nice!

So here we are - final shots before paint goes on. And, of course, the obligatory flex shots, and there's plenty of that too. It's doing 6 batts in the pic but will do 7 although does rub on the body slightly (which I've hacked away at even more):

I've given it a quick run inside and am very pleased with the way it performs, better than I expected. It's still a bit top heavy for my liking but I'll sort that out another point.

And one for luck -

[jagsxr]

hi ph good pics i hava tlt which i have adapted and bought some wheel "wideners" so the stearing linkage did not interfear with the wheels if they do i cannot see for sure

Please refer to this link for wideners; CLICK

Edited January 18, 2008 by TWINSET
Please do not post links to live auctions, however well intentioned. Link replaced with ebay sellers online shop link

[TWINSET]

Allie

Instead of the redundant steering rod going across the rear axle, you can take a short tie rod from the

knuckle to a ball stud screwed into the axle case on either side.

Gimme a shout if you need hardware

[Wrc action]

Lookin very nice - And i agree with Twinset about fixing the rear axles as that is what I have done and its a very simple solution that shouldnt get caught on anything.

Lookin fwd to the final pics.

Ryck

[Petrolhead]

Thanks for comments. Got rid of the steering rod for the suggested solution above.

It's all done now - painted up the body and fined off a couple of remaing bits and bobs. To see the final pics, go TO THIS LINK

A big thanks go out to Twinset who's offered advice throughout this project, I owe you a pint (of Coke ) Thanks a lot mate! Also thanks go to my dear old Dad who's helped me when I've got a bit rutted down in certain parts of the build.

It's been a great experiece not following any set rules and building it from your head. I'll defo do another one again some time soon.

Taster of final thing -

http://www.tamiyaclub.com/showroom_model.a...77&sid=3221