BMI's DB12R

[Nova F1 Racer]

Originally Posted by SRW141

Do you own one?

Nope, sorry, I was kidding because the IRS direction that came with the kit had it as part of the assembly instructions... The car is going together nice and slow...... And easy....

[InspGadgt]

I'm wondering if Apex meant more something along these lines...Most link cars have adjustable links so any inaccuracies in the manufacturing can be adjusted out in the links to keep the rear from binding. On CRC cars they have a solid link so the center pivot mount is slotted so to square up the rear pod you just loosen the 2 nuts on top of the center pivot mount, let the chassis sit flat, then tighten them down again. Is there anything like that on the DB12R or will it always come perfectly drilled? I assume the latter cuz the car just looks perfect

[protc3]

this rear end does work differently.all of the pivots are machined,not molded and the pivot balls are threaded and solid mounted to the pod and the center ball is solid mounted to the chassis.there is no slipping on this rear end.the only way to tweak it is to break it.there is no adjustment needed to get the rear to squared up,it is a precision setup that is self alligned.it cost me more to do this but i wanted it to be perfect.now tweak issues and it takes the hassle out of the setup.

if anyone has any questions on the build up of the car or wants some tips,feel free to shoot me a PM and i will help you out.thanks again for purchasing BMI

[InspGadgt]

Just like I thought everything's perfect

[protc3]

i wanted everything to self allign to take the nonsense out of the build.i didnt do to much cost cutting on the car because i wanted the best possible product i can do.i took alot of time figuring out how to perfect the rear end of the car.minimal parts made a more solid rear end.this is why i went to the 1 piece central pivot.the ball lines itself up perfect and the pivot does also.all the carbon fiber parts are machined on the CNC machine in one shot without reclamping to ensure dead on accuracy.the central pivot is machined on my CNC lathe and the holes are done with live tooling while its being turned.i spent alot of time and money on this car and may have went overboard. it is well worth it though.i am very proud of the outcome.

[InspGadgt]

Man I wish I had that kind of equipment to play around with

[protc3]

yeah,its alot of fun. on the next run of parts i will take some video of the machines running.its pretty wild.then you guys can get to see how much goes into the parts.

[Kropy]

Jason ~ So, How much extra is it to have my car built by you.....lol

[BlackedOutREVO]

Originally Posted by Kropy

Jason ~ So, How much extra is it to have my car built by you.....lol

Haha, As much as id like to build it, if he could build/tweek it, I would pay

[protc3]

man,thats 1/2 the fun of having the car

[protc3]

Originally Posted by Nova F1 Racer

It's here!!!!!!!!!!!!!!!!!!!!!!!!!!

at 11:39:03 AM a package arrived from Flordia...

With a caution sticker from BMI....

Faster lap time inside....

Let the build commence after actually reading the directions....

It looks bazilly.... Just a question.. the bearings, are they like the X-ray where you clean and oil first? Or are they press and press-in and run?

i always clean them out and re oil with a light oil.the grease in the bearings do not hurt the bearings,i just like them super free.they are Boca bearings.they are super high quality and will not bind during a race.no worries there buddy

[Nova F1 Racer]

Jason, need to talk ASAP sending email with home phone ...

[protc3]

Originally Posted by Apex

The center pivot is a given cause that's what allows for side to side and front to back movement between the rear pod and chassis.

What I'm trying to understand is how does the fixed piece of fiberglass (on the two side pivot points) allow for free side to side movement without binding?

The design is definitely very unique and maybe even revolutionary in 1:12 design. It's really a great design over spring cars cause it seems it would be very consistent as well.

it actually works similar to a T bar with a solid front mount with the exception that they are free pivoting.the way it works is obviously,the central pivot.then we have the flex plates get held in place in the front by a 4-40x1/2 inch screw that goes through the chassis,through the lower standoff and then the top standoff acts as a nut to hold it in place.now in the rear of the flex plate we have a machined ball capture that has the pivot ball inside of it that screws to the flex plate from the underside.on top of the ball inside the ball capture we have a small machined delrin pressure plate that looks similar to a countersunk washer but has a ball shape instead of a countersink that is placed on top of the ball.once it is screwed to the plate,you now have the 10-32x1/8 set screw that goes into the top of the flex plate that pushes on the small pressure plate to allow for you to adjust the verticle play out of the ball.this eliminates all the play in the ball socket. all 3 pivot balls are threaded and screw directly to the lower pod plate.the center pivot ball mounts to the chassis and the pivot itself is 1 piece and mounts to the lower pod with 2 4-40x3/8 screws.all are located with the flathead screws that secure them.now when you twist the pod,it bends the flex plates for spring tension.this is very consistant spring tension and does not wear out the plates easily due to the relatively short movement.it is a little strange when you see it work but it is the most smoothe pivot action i have ever seen with no slop at all and very,very durable.in order to snap one,it take 10 x the force of just bending and snapping it due to the structure it creates. the car doesnt tweak due to the structural strength of the rear end also.my car hasnt been on a setup station since february.i got tired of checking it for no reason.the only time i need to check it is if i am using the set screws to increase the side spring tension.you only need to check it 1 time for the initial setup though.i am very happy with the outcome of the rear suspension.

[Kropy]

Originally Posted by protc3

man,thats 1/2 the fun of having the car

Tell me about it, I'll have (2) cars to build here in the next few weeks

[Vicko]

wow since X is now on the BMI team< I cant wait for the second batch of cars come out so I can get 1 and let him set it up for me, since we go to the
same loca track