bilinvic's DMG IFS B1B Bomber Build

[SCREAMER]

I think he's asking for part numbers. Don't you speak French, Bil.

[cmbscx10]

Originally Posted by svt923

The way to keep the motor mount from loosening up is drill out the threaded holes in the plate with a 3mm bit and run M3x30 button head screws in from the front and a lock nut in the back. Same concept as the Super Shafty and BWD plates but it works well with the stock plate too.

I tried this for the first time. Have in hand and have used SS mounts but this is In a low power scaler so I figured I would give it a shot.

[Oliv01]

Sorry for my english, i wanted to know what shock absorbers take, thanks

[bilinvic]

My B1B shocks are Gmade 93mm XD Diaphragm shocks up front. The rears are Proline Powerstroke SC (rear) shocks and Axial Yeti Icon (rear) shocks with no springs.

[Oliv01]

Hello thx
Shock proline 118mm or 128mm??
Thx

[bilinvic]

https://www.prolineracing.com/perfor...e-shocks-rear/

[bilinvic]

My B1B will be transforming into a B2B and the first shipment of parts to convert the DMG's B2B kit has arrived. I'm quite excited to have a fully independent suspension bouncer/crawler in my collection. My B2B will be built primarily to crawl and occasionally rock bounce (which will likely be more often than not after hearing how plush the suspension is from Brian aka SCREAMER). SCREAMER's Quicksilver B1B/B2B thread has been a great source of info and inspiration.

Here's what I have so far:

STRC Aluminum HD Rear Camber Link Mount for EXO Buggy (Orange)
STRC Aluminum HD Rear Chassis Brace for EXO Buggy (Orange)
STRC Aluminum Rear Hub Carriers W/ Over-sized Bearings for EXO Buggy (Black)
Axial EXO Pin 3x29mm Grooved (For the Hub Carrier to A-Arm Pivot)
Axial EXO Rear Toe Block Set; Aluminum
Axial Spring 14X90MM 3.01 LBS/IN Super Firm Blue (For the Yeti Rear Shocks)
Axial Axial Racing M3x61mm Hex Socket Button Head Screw Shaft
Axial Racing Yeti/EXO Bulkhead
Locked Up RC FI Lunchbox Spool
RPM Rear A-Arms EXO Buggy
Team Fast Eddy Single 10x15x4mm Rubber Sealed Bearings
Team Fast Eddy Single 5x11x4mm Rubber Sealed Bearings

The front components will remain status quo....Axial locker, 38/13 gears.
The rear diff will utilize a LURC locker and 43/13 gears.

I will likely use the VP / Incision axles up front and Axial universals in the rear for now and wee how they hold up.

More to follow once the DMG ships my B2B conversion kit.

Now I have to figure out what I will do with the parts that will come off the B1B rear end.........

[bilinvic]

I have the rear end mocked up as I impatiently await the B2B conversion kit from the DMG.

I didn't use Axial EXO Pin 3x29mm Grooved (For the Hub Carrier to A-Arm Pivot) because it's too short with the wider RPM A-arms. I used Axial Hex Button Head Screw Shaft 3x35mm (AXA0125) instead.

The upper camber links are from the parts box...Originally from a Gmade R1; solid 7mm aluminum rod with 4mm threaded grub screws (20mm long). Blue RPM Jato & Revo link ends match the front end.

The LURC lunchbox spools are very nice. I had to file a slight bit of material off of the Axial Yeti/EXO axle tangs to fit in....it's still very tight!

I think that I am going to save the Yeti universal axles for spares for the front end. With a little bit of research, I discovered that original SCX10 diff cups are the exact same that are used for the EXO rear end (AX30366) and I just happen to have a brand new pair of them in my parts stash. I will order Axial EXO Dogbone Set 7x94mm (AX30379) and I will be good to go. Using the dogbone axles in the rear will be good since they obviously won't be used for steering and they are relatively inexpensive; plus they are easy to replace if need be. The 94mm length (vs 92mm) will be welcomed since the dogbones are pretty close to the end of the diff cups in full droop.

There's nothing else I can pre-assemble until the B2B kit arrives.

[*Old*]

Originally Posted by bilinvic

I think that I am going to save the Yeti universal axles for spares for the front end. With a little bit of research, I discovered that original SCX10 diff cups are the exact same that are used for the EXO rear end (AX30366) and I just happen to have a brand new pair of them in my parts stash. I will order Axial EXO Dogbone Set 7x94mm (AX30379) and I will be good to go. Using the dogbone axles in the rear will be good since they obviously won't be used for steering and they are relatively inexpensive; plus they are easy to replace if need be. The 94mm length (vs 92mm) will be welcomed since the dogbones are pretty close to the end of the diff cups in full droop.

There's nothing else I can pre-assemble until the B2B kit arrives.

That is interesting. Thanks for sharing that.
Very interested to hear how they hold up with power you're running. That would be a much cheaper and easy to fix solution if/when they go down.

Btw, I'm same as you, got my parts are ready to assemble, just need the DMG plate.

[SCREAMER]

I'm so excited to see both of your builds!

[CoolRunning]

That is a seriously impressive build!

I just wonder if the rig really crawls better than a solid axle bomber? I watched your vids and that SCX10 seemed to easily get up the same climbs the IFS bomber seemed to struggle at. The front suspension seems to lift the chassis up and one wheel is just in the air where the SCX10 articulates like you'd expect and just cruises up. Now I know that is a well developed SCX10 but none the less, there seem at least to me in those vids that it crawls far better.

I also wonder about the robustness of the locked from diff. Many guys seem to have tried and said their Yetis blow out stuff in the front end with a locked front end and frequently go back. Maybe there is new gear out there that is tougher for crawling and fast bashing?

It's an amazing truck none the less and probably the best 'rock racer' (at least in my personal op) you can probably build. Basically a killer scale KOH rig.

[bilinvic]

I fell behind documenting my B2B conversion...sorry!

I ended up ordering DMG's full B2B kit instead of the partial B1B to B2B conversion kit. As mentioned in other B2B builds, everything bolts together perfectly...no messing around trying to make parts fit; great job Jerry.

For the rear driveshaft, I used Gmade (Junfac) hardened steel shafts, their narrower profile results in not having to modify the spur cover to provide clearance. I have never broken one of these shafts in the numerous rigs that I use them in. I used an Axial WB8 HD Wilboar driveshaft in the front.

Here are some of the assembly photos:

[bilinvic]

In the photo below, I used ProLine 8mm wide hexes until I received a pair of Vanquish .350 SLW hubs and then I will go back with the 6mm Axial aluminum (Wraith) hubs. I needed a couple extra mm of spacing between the lower A-arm and the inner beadlock screws on the SSD Rock Racer wheels.

For the rear Axial Yeti shocks upper mount, I used Axial Silicone Shock Bushings 7.5x8mm (AXA1356) instead of Screamer's fuel tube trick. These bushings work perfectly and does not cause the rear shock to bind on the angle required to mount to the lower A-arm. For now I'm using Axial 14x90mm 3.01 lbs/in super firm springs (blue stripe). I may try one spring softer just to compare performance characteristics.

I mentioned earlier that I ordered a pair of Exo 7x94mm dogbones to be used with standard SCX10 stub axles (dog bone carriers). They will work, but could stand to be slightly longer for better dogbone pin engagement when in full droop. I have since discover that 7x96mm dogbones are available (AX3041 and I will try these soon. Until that time, I'm using the Yeti 92mm universals which fit perfectly. I do have some limiting straps that I may use if needed to limit maximum droop angles.

[bilinvic]

[bilinvic]

Finished building....time for testing and tuning!






The rear tires are purposely toed in for straight line performance.

[bilinvic]

My intention is to build this B2B primarily for crawling and rock bouncing as required; it's not going to be a basher/high speed machine although it could easily with it's HH PP 3500kV motor!

The independent front and rear suspension is super plush...which means a drop test video is in order:

[bilinvic]

My backyard was the venue for the B2B's first test session so that I can easily adjust what's required in the comfort of my shop. I know what lines are easy and which ones are advanced so that I can judge the B2B's crawling performance in comparison to my other rigs.

Immediately I realized that more weight was required up front to compensate for the shorter wheelbase (compared to my other 2.2 RCs). I added 98 grams (3.45 oz) using 1/4 oz lead balancing weights in addition to a 23g Yeah Racing aluminum NOS bottle behind the front bumper. I wrapped the lead weights in electrical tape and then a layer of "carbon fiber" duct tape to make them cosmetically pleasing to the eye!!!!

During this test sesh, I was probably conquering 75% of the lines that my dedicated crawlers could accomplish but was cut short due to bending the middle pin within the HH SHV500 servo...ugh! I was using the Flat Iron XL tires with rather firm CI DD foams F&R. I have since changed out the foams with softer foams for better rock crawling performance.

I'm pretty happy, but I know I can make it better. It's just so kool to watch all four wheels articulate independently. Also, to my surprise, the aluminum skid/backbone has not been as limiting as I thought it would be. The majority of the scratches are where the normal skid would be. The non-existence of torque twist is truly awesome and appreciated.

[bilinvic]

Now that the initial backyard testing and tuning was for the most part complete, I took the B2B to my regular test grounds for a thorough testing. There are some really extreme climbs at this location and because my buddy nostopinLucR and I test here regularly, we know that if some specific climbs are accomplished, then that particular rig is dialed in. In other words, we know the benchmark for success out on the trail.....or whether it's back to the bench for further tuning!

So how did the B2B perform in a crawling environment? It did extremely well. It accomplished every climb that we use for testing although it did require more effort than some of my other hardcore crawlers....but that's not a bad thing because the climb is even that more rewarding once at the top. Some of the lines are even easier because there's no diff pumpkins to worry about hitting. The centered ground clearance is a nice change.

I did find that I could use a little more front end weight to give the front wheels some more traction when on some really steep crawls. I also need to drop the drag brake so that it rolls a little more freely when off the throttle. (When I got home I went from 50% to 35% drag brake on the MMP).

I also thought that my shocks on all four corners were too heavily sprung, I will change the springs to a slightly lower spring rate.

I do wish I could get an extra 1/2 inch of wheelbase though...I really think this would make a big difference for crawling. The only problem I can see if the WB was longer is how and where the rear upper shocks would mount.

All said and done, I'm ecstatic...this B2B is going to be a blast out on the trails going up against solid axle 2.2 rigs.

When I got home, I discovered that I had bent a rear Axial Yeti universal axle. I usually test my rigs pretty hard so that I can discover weak links sooner than later and I suspect this was caused from a tumble. I will definitely get the 7x96mm dogbone axles and see how they perform on the rear. I'm hoping they will work out successfully.

Here's the pics:












Of course I had to try out that plush suspension with some airtime!









....and the bent axle:

[bilinvic]

I almost forgot one important note...this machine sidehills unlike no other...it's really phenomenal.

[bilinvic]

I added another 42g (1.5oz) of lead ballast to the top of the front diff, just abaft of the shock tower.

Total weight with one 3300 mAh 3S battery is 8lbs 8.55oz (3.87kg).