Scratchbuilding Brakes - Part 2 "Calipers"

[mikevillena]

Hey gang,
Some build notes on calipers....
NOTE: Because there are as many caliper designs as there are manufacturers, you should refer to the pictures

of the particular brand and type of caliper that you are trying to replicate. I've chosen a simplified and early

AP RACING 4 piston caliper. For ease, I chose to construct the caliper assembly in halves. Note that some

caliper housings are cast as one-piece while others are two halves bolted together. Again, check your

reference photos. Additionally, I designed a little bit of "float" into the caliper assembly to accomodate any

warpage on the brake discs and the caliper assembly was built to be removable.

Here's an exploded assembly sketch:
http://i7.photobucket.com/albums/y293/mikevillena/disc%20brakes/calipersketch.jpg


To make the wheel cylinders (Part no.1), I cut 2 pieces of 7/32" dia. Evergreen tubing which were then

sanded to a uniform lenght of .060. I then glued both pieces onto a lenght of .040" x .188" Evergreen strip (Part no.2).
http://i7.photobucket.com/albums/y293/mikevillena/disc%20brakes/caliper001.jpg

After the glued joint has set, I trimmed off the excess strip and sanded Part no.2 to conform to the shape

of the siamesed cylinders. (see photo in step 5)
http://i7.photobucket.com/albums/y293/mikevillena/disc%20brakes/caliper002.jpg

I used a scrap piece of .040" thk.x 1.38" x .50" Evergreen to make Part no.3.
http://i7.photobucket.com/albums/y293/mikevillena/disc%20brakes/caliper003.jpg


http://i7.photobucket.com/albums/y293/mikevillena/disc%20brakes/caliper004.jpg

[mikevillena]

I glued the cylinders onto the scrap piece and marked out the design.
http://i7.photobucket.com/albums/y293/mikevillena/disc%20brakes/caliper005.jpg

I glued pieces of .060" x .188" strips (Part no. 4). Note the bias-cut end where the strip joins the wheel

cylinders.
http://i7.photobucket.com/albums/y293/mikevillena/disc%20brakes/caliper006.jpg

I glued pieces of .060" x .125" strips (Part no. 5) centered over Part no. 4.
http://i7.photobucket.com/albums/y293/mikevillena/disc%20brakes/caliper008.jpg

After the glued joints have set, I used my razor saw and file and beveled the laminations (see sketch).
http://i7.photobucket.com/albums/y293/mikevillena/disc%20brakes/caliper009.jpg

I trimed and filed Part no. 3 to shape. I then drilled and ground out the holes for Part no. 6. The holes

are sized for the pistons to freely slide in and out. Note: You may omit this step (and Part no. 6) and simply

glue the finished brake pads in place during final assembly.
http://i7.photobucket.com/albums/y293/mikevillena/disc%20brakes/caliper010.jpg

I started the brake pads (Part no. 8) by beveling the ends of a lenght of .040" x .188" strip. I also added

a notch as shown. Note: Check your reference photos as brake pads tend to vary greatly.
http://i7.photobucket.com/albums/y293/mikevillena/disc%20brakes/caliper011.jpg

[mikevillena]

I trimmed Part no. 8 to lengh and glued it onto a lenght of .015" x .250 strip (Part no. 7). After the glued

joint had set, I trimmed Part no. 7 to lenght and shaped the ends.
http://i7.photobucket.com/albums/y293/mikevillena/disc%20brakes/caliper012.jpg


I used 5/32" dia. tubing to make the pistons (Part no. 6). I cut the pistons to lenght so that they sit flush

inside the cylinders.
http://i7.photobucket.com/albums/y293/mikevillena/disc%20brakes/caliper014.jpg

I glued the pistons (Part no. 6) onto the brake pads. I used slow setting liquid cement to help position

the pistons so that the sub-assembly freely slides in and out of the cylinders.
http://i7.photobucket.com/albums/y293/mikevillena/disc%20brakes/caliper015.jpg

I used lenghts of .188" x .188" strip to make Part no. 9. These were glued into place and shaped in a

later step.
http://i7.photobucket.com/albums/y293/mikevillena/disc%20brakes/caliper016.jpg

Here's a shot of the nearly finished caliper half and the brake pad.
http://i7.photobucket.com/albums/y293/mikevillena/disc%20brakes/caliper017.jpg

I then sanded the caliper half to shape. I made the other caliper half using the same procedures.
http://i7.photobucket.com/albums/y293/mikevillena/disc%20brakes/caliper018.jpg

[mikevillena]

I lined up and glued the caliper halves together.
http://i7.photobucket.com/albums/y293/mikevillena/disc%20brakes/caliper019.jpg

Because I was trying to replicate a cast one-piece caliper, I used spot putty to fill in the gaps between

halves.
http://i7.photobucket.com/albums/y293/mikevillena/disc%20brakes/caliper020.jpg

After sanding the filled areas, I drilled a small pilot hole through the caliper.
http://i7.photobucket.com/albums/y293/mikevillena/disc%20brakes/caliper021.jpg

I then swithced to a larger bit and sized the hole for a .040" dia.plastic rod (Part no. 10).
http://i7.photobucket.com/albums/y293/mikevillena/disc%20brakes/caliper022.jpg

I marked out my backing plate onto a piece of .040" thk. sheet.
http://i7.photobucket.com/albums/y293/mikevillena/disc%20brakes/caliper023.jpg

I cut out and sanded the backing plate to shape. The center hole is sized for a tight fit around the hub

carrier on my TL-01 chassis because I wanted to be able to remove the brake assembly for racing.
http://i7.photobucket.com/albums/y293/mikevillena/disc%20brakes/caliper024.jpg

I marked out a notch on the backing plate to clear the features on the caliper. I also filed a flate area on

the caliper where it mounts onto the backing plate.
http://i7.photobucket.com/albums/y293/mikevillena/disc%20brakes/caliper025.jpg

[mikevillena]

I had to add some scraps to the backing plate as I had miscalculated where the mounting holes would

be. I drilled the holes on the backing plate using the caliper as a guide. I temporarily pinned things together

with some .040" dia. rod.
http://i7.photobucket.com/albums/y293/mikevillena/disc%20brakes/caliper026.jpg

I transfered the correct outline of the backing plate onto another piece of .040" thk. sheet and made a

new one.
http://i7.photobucket.com/albums/y293/mikevillena/disc%20brakes/caliper028.jpg

Drilling the new backing plate for mounting holes. I had to re-adjust so that the center fastener (Part no.

10/11) clears the brake disc.
http://i7.photobucket.com/albums/y293/mikevillena/disc%20brakes/caliper029.jpg

I had to trim the backing plate a little after I found some rubbing between it and the wheel.
http://i7.photobucket.com/albums/y293/mikevillena/disc%20brakes/caliper030.jpg

A final check for clearances between the caliper and the wheel spokes.
http://i7.photobucket.com/albums/y293/mikevillena/disc%20brakes/caliper031.jpg

I washed and scrubbed the parts thoroughly with an old toothbrush prior to painting.
http://i7.photobucket.com/albums/y293/mikevillena/disc%20brakes/caliper032.jpg

The backing plate was sprayed with some Plasti-Kote Bumper Paint (black).
http://i7.photobucket.com/albums/y293/mikevillena/disc%20brakes/caliper034.jpg

The brake disc was sprayed with Metalizer Stainless Steel. After the required waiting period, I used

some facial tissue and q-tips to buff out the swept areas. I left the center section umpolished and I used a little

black wash around the bolt heads.
http://i7.photobucket.com/albums/y293/mikevillena/disc%20brakes/caliper036.jpg

[mikevillena]

The caliper assembly was sprayed with Metalizer Gunmetal (mixed with a little flat black) and left

unpolished. The fasteners (Part nos. 10 & 11) were made using lenghts of .040" dia. rod and 3/32" dia.

tubing. The fasteners were painted Metalizer Stainless Steel and buffed. The brake pads were painted with

Metalizer GunMetal. After the painted parts have dried, I simply popped in the brake pads and pinned

everything together using the fasteners. The center fastener was glued in place.
http://i7.photobucket.com/albums/y293/mikevillena/disc%20brakes/caliper037.jpg


http://i7.photobucket.com/albums/y293/mikevillena/disc%20brakes/caliper038.jpg

The new disc brake looks a heck of a lot better than a very early (and crude) set that I had made a few

years ago.
http://i7.photobucket.com/albums/y293/mikevillena/disc%20brakes/caliper039.jpg
Some final notes on Metalizer paints : Metalizer paints don't stand up well to a lot of handling. Metalizer does make a clear top coat to seal the paint for a more durable finish. The downside is that you lose a bit of luster on polished finishes.
I hope this post is informative and that you've gained some ideas for your own detailing project. Have fun :D

[Buggyracer28]

THAT IS AWESOME!!! they look so real! GREAT job!

[Silent Night]

Wow! They look like they are really work.. But with your brakepads, you said that you made them so they can slide.. If they slide out while you were driving it, wouldn't it rub agaisnt the disk brake making the car slow down a bit and melt it? Or will you just be taking it all off while you drive.. It would suck if you entered it into those concourse compitions where you have to race it as is

[MT2 owns you]

:eek: :eek: :eek: :eek: !!!! AMAZING!!!! thats just amazing! looks real too!!

[Rtsbasic]

Thats damned impressive..looks really good. Much better than I could ever do. Really detailed, made for an interesting read :)

[Silent Scope]

Hmm.. IMO i think the calipers would look better in red..

[supernitro_guy1]

Incredible, once again, Im drooling (Smacks Himself trying to come back to reality after dreaming with those brake sets)..............OUCH!!!!!!!!!

[mikevillena]

Hey guys,
Thanks for the compliments :o . I hope you're all working on your own versions (c'mon guys, you can do this....I just showed you how! :D ). I went with a simple design and chose a simple finish/paint scheme. A quick glance at any "Tuner" magazine will yield numerous brake designs and colors so you can paint them red, blue, etc. Someone should also try painting the disc with Alclad II Chrome as I'd like to see how that looks. I omitted some finishing touches such as brake bleed nipples and cross-over piping to simplify this article so you might want to add those too.

Silent Night - I built some float into the calipers and I didn't paint the brake pad faces so that if the pads contact the brake discs, they won't grind the finish on the discs.

Thanks gang.... :D
Mike V

[AirBoston]

Loots to me like the driver needs to be sent back to school. With all the scaring on the rotors, I'd say he's been dirt tracking too much.

Looks good!

[mikevillena]

Loots to me like the driver needs to be sent back to school. With all the scaring on the rotors, I'd say he's been dirt tracking too much.

Looks good!

AirBoss,
What did you expect? After all, the driver is a Formula Ford drop-out :D Danged wet leaves!!!!!! $&#**#@% understeer!!!!!!!!!! (treshhold braking) oh sh*t... :eek: oh ... :eek: (arms and elbows flailing about) .....(mumble, mumble)...(sound of gravel scraping the tub)....lazy corner workers!!!!! :mad: (gesturing wildly) :( :rolleyes: :p :D (back underway, remembered to let in the clutch so the engine didn't stall...whew!)..zoom...repeat at the next corner.... :D

[mikevillena]

Another "bump".

[rc man37689]

Another "bump".
what else is there to say? u r 1 sick artist lol
u make it look more than real

[mikevillena]

what else is there to say? u r 1 sick artist lol
u make it look more than real
Hey thanks rc man. So go and grab some plastic and try your hand. It just takes a little bit of practice and patience but can a lot of fun and extremely satisfying when you can pull it off.

[Aluma]

wow. mike does modeling work that just blows a persons mind away. Truly an inspiration for us all.

[mikevillena]

wow. mike does modeling work that just blows a persons mind away. Truly an inspiration for us all.
Thanks Aluma . So, where's your entry into this month's competition? C'mon.....you can do it.