ETLB Squawk Forums — Archive

I used a free on-line CAD program http://OnShape.com to create some drawings for the parts needed to add bicycle disk brakes to my 1030.

Caution: My bird is not yet complete so no real world testing has been performed but so far they do work really well as a parking brake.

Because of attachment size limitations I will need to attach the PDF drawings in additional posts, here are some pictures of the finished product

EDIT:
Updated drawing with reinforcement can be downloaded from here:
https://ulbuilder.files.wordpress.com/2016/10/caliper-mount-drawing4.pdf

Modified Axle mount drawing

Caliper Mount

Rotor Adapter

Ok thats great.

Looking forward to your testing

regards Arthur

Nice drawings and workmanship. Thanks for posting.
Dick

Looks great - bet they'll stop a Max pretty quick.

bruce

Keep this stuff coming! I am leaning very heavily in this direction!

Parts I used:
$20 calipers and pads https://www.amazon.com/dp/B01FJV5Z54/ref=cm_sw_r_cp_apa_j0Q.xb255XSRC
$13 two rotors https://www.amazon.com/dp/B019T9SBA8/ref=cm_sw_r_cp_apa_C1Q.xbRXY7J2Q
$8 locking brake lever https://www.amazon.com/dp/B019YTZB0G/ref=cm_sw_r_cp_apa_L2Q.xbX1FRMX6
$9 dual brake cable https://www.amazon.com/dp/B00KWLLCV8/ref=cm_sw_r_cp_apa_G3Q.xbSFDFY2M

Just add aluminum to fabricate the brackets and your done.
Total of about $75 for everything.

Even if they don't perform at the awesome level I bet they will work as well or better than band brakes while having a similar cost. Not sure if they are lighter than band brakes.

The calipers I used have a 50.5mm bolt spacing where normal bicycle calipers using the IS mount have a 51mm bolt spacing so depending on what you use you might need to adjust my drawing a bit.

It seems rather difficult to find right/left calipers so you can have symmetric cable routing. I'd gladly pay more money for a higher quality caliper if I could find them but am satisfied with the cheap $20 Chinese set.

If hydraulic brakes are desired they make those for bicycles too.

Very sanitary and pro looking work, they look fantastic and should perform just as well, it's inspiring to see innovations that are so well thought out and documented, outstanding fabrication skills!

Quoted from ulbuilder

Caution: My bird is not yet complete so no real world testing has been performed but so far they do work really well as a parking brake.

I built my brakes very similar to yours.  When I first tried using them the mounts flexed so much that the calipers bent the rotor.

What did you do to prevent the flexing?

If I lock the brakes and try to turn the wheel there is a little flex in the caliper mount. I don't think it's enough to cause a problem but ideally there would be no flex at all.

Quoted from ulbuilder What did you do to prevent the flexing?

If I lock the brakes and try to turn the wheel there is a little flex in the caliper mount. I don't think it's enough to cause a problem but ideally there would be no flex at all.

When I first installed the brakes I saw the same thing your are...a little flexing when trying to turn the wheel by hand.  The first time I used the brakes to stop the plane the mount flexed so much that the caliper bent the rotor.

I added a steel cable restraint from the top of the mount back to an anchor point on the landing gear tubes (my plane is an Eindecker with a nice horizontal tube behind the wheels).  The cable keeps the mount from moving forward.

Here is a site that shows how one guy installed his brakes:  https://www.flickr.com/photos/hawk_ace/albums/72157625967127064/page4

I'm going to add the blue reinforcement pieces, this should be sufficient to prevent any flexing.

I've updated my drawings with the newly added reinforcement to prevent flexing.
Also combined all the drawings into a single PDF file.

Unfortunately the new PDF file is a little bit larger than the maximum file upload size on this forum.
You can download the new drawing from my site here:
https://ulbuilder.files.wordpress.com/2016/10/caliper-mount-drawing4.pdf

Hi from France,

I was planing to mount brake discs on my 1600R...so i find how now  ! Many thanks for your drawings and pics, they will hep me in my mount ! i have ordered yet the caliper and discs on Alipress this day...

So i have to "traduct" all the measurement in métrique ! perhaps the program you use can make it automaticly ? if you can edit your PDF here with this it will be GREAT !

I'm finishing mounting a Simonini Victor 1 engine on my plane, it replace the antic 447....a lot of work this winter !

Have a nice day

And sorry for my bad english.....

hey your English is a lot better than my French. you have a great day too.

monte

Frenchkiss, if you get an account created on [url]OnShape.com[/url] I can share my drawings with you. I *think* you could convert to metric without much work.

I think all I need is your email address that you use for your OnShape account and I can share the file with you.

Hi,

i have create an account on oneshape,

i send you my mail by private message

many thanks for this

oh and pictures of your plane too...

Now that I have about 30 flight hours I can report how well the brakes work.

The brakes can hold the airplane stationary, on grass, at full throttle with my Kawasaki 440a. It does take significant pressure on the brake lever.

I've used them to slow down after landing without issue.

Nothing has broken or bent.

They do require occasional adjustment, I think mostly because the adjustment screws on the calipers loosen from engine vibration. I did have a shaking, rattling and rolling Hirth F33 the first 20 hours....

I have a locking brake lever on my stick. Very nice when starting the engine or idling on the taxiway waiting for traffic to clear the runway.

I think the weakest link in the design is the rotor adapters but so far they are working great.

I've had issues with tire clearance and cannot run the tires I like best.
But had I had those tires before cutting the axle I could have made the axle a little longer to accommodate some spacers to resolve the issue.  If my axle was just 1/2" longer.....

Out of curiosity, since I too have a 440a...

I have band brakes.  Can they hold the plane stationary at full power?

What are the pros of upgrading to these disks? I happen to have all this hardware from a gokart before I converted it to hydraulic brakes.

Also, how does the plane not tip forwards when under brakes at full power?  Elevator keeps the tail down?

My max is tricycle gear so no tipping issues for me.

If I already had band brakes, don't see any compelling reason to switch to disk brakes. I look at this as an option for a new build.

I am able to hold the airplane at full power. But it does take considerable pressure on the brake lever.

ulbuilder,

The only thing I would add would be a pair of brake 'noodles' from a bicycle to turn the brake cables. It's what I've done on my 'max as you can see in the first two pics below. I used the original band brakes to save time trying to work out clearances, etc, and just made up some new brackets out of 6082 bar. However, one other thing I did was extend the axle mounting brackets from the two bolt pattern to an amended three bolt pattern as can be seen in the last picture. This means the max weight can be increased up to 590lbs according to the plans.

I've considered the three bolt mounts ever since I saw a picture of them here long ago.

The noodle is a great suggestion, thanks.

A note of caution:
You do not want really effective brakes on a conventional gear airplane (tail dragger). If you fly any of the Champs, Cubs, Luscombe's, etc. you will be disappointed in the brakes, this is part of the design. You need to think way ahead of the aircraft and  anticipate where you will turn or stop. Great brakes can easily put you on your nose or over on your back. If you have  tricycle gear, good brakes are indeed and asset.
Joe - 800+ hours in tail draggers.

Also, avoid any brakes that can "grab"!

https://www.amazon.com/Strida-ST-340-03-B-P-RR-Disc-Brake/dp/B01HIY8OVW?th=1
https://www.amazon.com/dp/B01HIY8ONA/ref=cm_sw_em_r_mt_dp_U_.Al.Eb6GKN1B5

here ya go, left and right.   a little pricey but they are nice (i have a pair of them)

Nice looking mount for the brakes, I too have purchased disc brake calipers for my tandem airbike build. I purchased mine through a bike parts online store, I was going to go with hydraulic actuation but felt the cable variety would be ample for what i needed.

I will post some pictures once i have finised the cad for mine.

On another note, in terms of cad software fusion 360 by autodesk is also free for hobby / personal use. I highly recommend it, particularly if you are using the cad in conjunction with a cnc router or 3d printer.

Cheers Alex