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Leethal Driver

Carbon Chassis Astute Mk II - help needed

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Afternoon All

Am attempting to make another home made carbon chassis for my newest Astute, and I want to try and make some improvements over the first effort. It's never going to be perfect but I think I can do a little better.

So, my two questions for the pro's are:

1. I want to make some really tidy countersunk holes this time round. Last time I just used a bigger drill bit and it made some rough edges and looked a bit ropey in places. The replacement socket head hex screws are 3mm with a 6mm width head. Do I need a 6mm countersunk drill bit or...what? Having had a brief look, a 6mm counterunk drill bit has the bit itself as 6mm wide with the countersink part wider still so presumably I need a smaller countersunk bit?

2. First time round I used my Dremel fitted with a cut off disc to cut the chassis plates which wasn't too bad but wasn't ideal either (trying to cut round edges at the top of the shock towers with a cutting disc at 90deg spinning in the opposite direction is tricky!). Not having access to a vertical bandsaw is there any sort of Dremel type affair that would give me something akin to an electric carving knife? Can't see one myself but maybe there's some other brand I don't know about.

Kinda hoping someone'll go "you need one of these and one of these chief" lol!

Anyway, must be something in the water, lots of great looking Astutes popping up at the mo!

Cheers

Lee

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With countersinks, you just need a 90 degree one for metric screws

The idea is you stop when you've gone deep enough to make the top of the hole 6mm - Even if you find a 6mm diameter cutter, if you go too deep with it you just end up with a 6mm diameter hole with a tapered bottom!

All my countersinks are around 10mm-20mm diameter at the top of the cutting head - like this

If you can, use a pillar drill so you know you're hitting the chassis plate square - if you're not square to the plate when you start countersinking, it'll throw the screw out of square too and the hole will be oval.

No idea if you should be countersinking CF fast or slow though, but make sure you don't catch a lungful of the dust!

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Much obliged there Mr Twinset, just bought myself a slightly smaller 8.3mm cobalt countersink (less chance of doing damage I think) and we'll see how we get on this weekend (in between carting sackfuls of plaster out of the 2nd floor bedrooms :angry:). Purchased a mix of black socket/button screws also to replace the gooey ones I barely managed to get out of the chassis too.

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LOL there's no less chance of doing damage regardless of the diameter - it's the depth you go that'll upset you

I've nacked up loads of alu with a pistol drill and a countersink

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Well after laying my hands on the cobalt countersink I got to work in the garage and hey presto, some lovely round holes:

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And a bit of tinkering later in the mess room:

P1010354.jpg

Need to tidy up the other D1 slot and shave a bit off to get the hinge to align correctly but nothing major and will get to the damper stays at the weekend. Built the HiCaps for the front, golly they're nice bits of kit. Found the gearbox housing has a split screw hole :o. Ah well, can't be helped.

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Love your work Lee. Please keep the updates coming. Will you be doing the shock towers in cf on this one also? Let me know when you start taking orders ;)

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Love your work Lee. Please keep the updates coming. Will you be doing the shock towers in cf on this one also? Let me know when you start taking orders ;)

The Fibrelyte towers tend to be good value - its their pricing for the chasiss plates that makes using their kits a little prohibitive. Is it worth cutting your own towers ?

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Yep, will be making my own shock towers (got a template for the FRP part on the 959 front damper stay ready to go too) on Saturday; I did start cutting them the other day but got a bit keen and made a pigs ear of it. What did help this time round was having a bench vice to hand and then screwing the FRP chassis plate onto the CF chassis cut out (remembering to have the CF sheet the right way up this time :lol: ). Made it much easier to align the screw holes and also to shape/sand the CF to the same shape of the FRP plate after cutting it out with the Dremel. It's not perfect by any means but it works for me and it looks good when it's built :).

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The wife rang and said she was going for a drink with her girlfriends, the kid is at a party so I took advantage of the free hour and a half :)

Got the shock towers cut and finished and started bolting together the front end. Rear shock tower is a poser as the gearbox housing has a cracked screw thread so am waiting for a new one.

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Have got some BF wheels in the dishwasher so I can then dye those, the Madcap steering arms and the 6mm blue ball ends black in one sitting. Trying to keep this one all Black Magic. :ph34r:

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Hmmmm, after seeing all these updates from 'Max and Grastens I thought I'd best pull my finger out and let you have a peep at what I've done on my Astute these last couple of weeks...for various reasons not much but I did get busy with the Rit. I think they look pretty cool and mean I can use my HiCaps for something else. More importantly I managed to not make a single bit of mess anywhere (which was good as the wife wasn't best pleased I was heating these through on the range whilst she was cooking diner earlier, even if I did point out there was at least one spare hob all round between the large saucepan of hot black permanent dye, dinner and the rest of the kitchen).

P1010366.jpg

The Blackfoot wheels, front body mount and yellow CRP steering blocks also came up trumps for my BF project as did the M3 roll cage, the steering arms and the 6mm blue ball ends for my Astute, although the red BF chassis doesn't look like it'll take judging by the battery holders so far.

Eventually, I ran out of things to dye.

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After seeing Thommo's Astute GT I've been inspired yesterday and today to get on with this a bit so I could take a couple more pics.

Went back and added the MadCap front tower brace after reading 'Max's excellent guide, bearings throughout (replaced all the brass bushings), RR 23T steel pinion, MadCap rear end with heavy duty M4 upper links mounted slightly differently on the rear tower mount. Rear end is sitting a little high as the HiCaps are mounted on the lower tower mount with heavy oil (and that's why the front track looks a lot wider in the first pic), front HiCaps to go on but not sure on the MadCap front arms; the shocks look like they'll be a bit too far away from the shock tower for me so might go back to the Astute lower arms. Need to order some more black hex screws of varying sizes.

The Astute shocks came out really well in the black dye as did the front steering arms but I put the HiCaps back on when I realised I have nearly enough parts for another Astute (and what's the point of having HiCaps if you ain't gonna use em?!).

***** repro shell in Smoke or Black with some White TRF decals to go on top. Will be keeping this one.

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Awesome look mate.....

Indeed these Hybrid Tires and Lightweight Black wheels gives always a great look on all buggies....:)

so wats the plan for the body?

cheers

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Good stuff Lee. I'm glad you've picked this one up again. I like the relocated inner links for the rear upper arms. That's a great idea and should be well strong. Where did that move come from ?

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Necessity is the mother of invention :lol:

Realised I didn't have the right length hex screws in black to mount them horizontally through the bottom of the shock tower mount (and it saved me cutting out a brace per 'Max's suggestion).

Did note yesterday I forgot to put the dogbones in but that can wait for the weekend.

Not sure on the colour choices TamiyaEra. Might go with White actually now I think about it, that'd really stand out against the chassis/wheels. Decisions, decisions :blink:

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Necessity is the mother of invention :lol:

Realised I didn't have the right length hex screws in black to mount them horizontally through the bottom of the shock tower mount (and it saved me cutting out a brace per 'Max's suggestion).

Did note yesterday I forgot to put the dogbones in but that can wait for the weekend.

Not sure on the colour choices TamiyaEra. Might go with White actually now I think about it, that'd really stand out against the chassis/wheels. Decisions, decisions :blink:

Or u can go full black..:-)

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Teaser shots (pretty gash, I'm no David Bailey :P). Finished the front end, retained the MadCap front arms as the HiCaps fitted quite nicely in the end but a bit of tweaking here and there still required. Wing is not the colour scheme I've decided on but I've I can spray over this one as it's really very tidily cut out, rather than the half rsed job I'd do on the not-an-original Tamiya wing I purchased. Didn't make too bad a job on the shell, and will be using the original unsprayed undercowl. Got some very jazzy decals on the way hopefully. Oh, and that's an old (refurbed) Trinity Monster Horsepower I had lying in my box, soldered on some new connectors and away we go.

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Anybody knows where one can still find those black light weight Egress wheels?

eBay

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Dude. Nice build. I ended up using the fibre lyte chassis and shock towers. You've done a great job with this.

My build thread is in the vintage section, ive ended up going more super astute with my latest build, arms and hubs, the old madcap arms flex a lot. Keep the updates coming

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Hi leethal driver,

Could I ask you we're you got thoe custom decals from for your astute project as I have been looking for something along the same line for myself.

Cheers bond007.

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