FS Rocky Mountain Brakes, large drum.

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Model T Ford Forum: Classifieds: FS Rocky Mountain Brakes, large drum.
Top of pagePrevious messageNext messageBottom of page Link to this message  By George schmidt on Tuesday, June 05, 2018 - 08:16 pm:

I have a pair of large drum, Rocky Mountain Brakes for sale. If Iím correct, all the parts show to be present, except the Equalizer and rods. As the photo shows, the break pads show a lot of life,
Purchased them in a Model T Speedster and parts sale and do not need them, since I sold the Speedster. LOL
Iím asking $500 obo , plus shipping cost.
Sorry, no international shipping.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Brass TT on Tuesday, June 05, 2018 - 09:05 pm:

What is the OD of your 26/27 brake drum ? I am wondering if they would fit on my TT.


Top of pagePrevious messageNext messageBottom of page Link to this message  By George schmidt on Tuesday, June 05, 2018 - 09:14 pm:

I measured 11.5 in. OD
Iím not 100% if they would fit your TT.
George


Top of pagePrevious messageNext messageBottom of page Link to this message  By Spencer Vibert - Granby ,CT on Tuesday, June 05, 2018 - 09:18 pm:

George are they originals or repro's


Top of pagePrevious messageNext messageBottom of page Link to this message  By George schmidt on Tuesday, June 05, 2018 - 09:36 pm:

I canít say if repoís.. I do not see any model number, etc. since they have been painted.
Can I take better photos of a location on the brake, to help you determine.

George


Top of pagePrevious messageNext messageBottom of page Link to this message  By George schmidt on Tuesday, June 05, 2018 - 09:41 pm:

Two more photos, if this helps.


Top of pagePrevious messageNext messageBottom of page Link to this message  By George schmidt on Wednesday, June 06, 2018 - 12:12 pm:

Bt


Top of pagePrevious messageNext messageBottom of page Link to this message  By George schmidt on Thursday, June 07, 2018 - 09:55 am:

Bt


Top of pagePrevious messageNext messageBottom of page Link to this message  By Donnie Brown North Central Arkansas on Thursday, June 07, 2018 - 06:59 pm:

George. They are not repro or original Rockies. They appear to be loosely patterned after the AC brakes. They could be the new repro AC brakes, but Im not for sure, as Im not familiar with the new repro ACs. The brake shoe L shaped guide is unique. I have never seen that style before. Since the shoe pivot is at the rear of the shoe they are going to function like the repro Rockies. They will stop very good going forward and be "self energizing" but not hold well in reverse. Overall they look like a nice set of brakes. good luck with your sale...


Top of pagePrevious messageNext messageBottom of page Link to this message  By Ron Horton, Utah on Thursday, June 07, 2018 - 07:17 pm:

PM sent.

Ron Horton
801-782-4171


Top of pagePrevious messageNext messageBottom of page Link to this message  By George schmidt on Friday, June 08, 2018 - 01:52 pm:

Sold, thanks to MTFCA.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Tim Knapp on Saturday, June 09, 2018 - 12:12 am:

The "L" shaped bracket at the rear looks to have a spring mount, that will let the brake band move some around the drum. It would seem that this design would specifically address the need to "self energize" in order to work equally in forward or reverse. I will be interested to hear if Ron finds that they do actually work that way.

The design does look like somewhat of a copy of the AC design. All the parts look to be cut or fabricated, and not cast. Period pieces usually are cast, and usually will have some manufacturer identification cast into the parts in the form of name, factory location, etc. My best guess is that this set is a fairly recent reproduction, with some thoughtful alterations built in. Maybe Ron will give us a follow-up report after they are installed. / Tim


Top of pagePrevious messageNext messageBottom of page Link to this message  By Ron Horton, Utah on Saturday, June 09, 2018 - 08:20 am:

Iíve got to come up with the rest of the parts needed and then get them installed, but after reading both Donnieís and Timís posts, will be interested to see how they work. I will put up a post ATT.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Donnie Brown North Central Arkansas on Saturday, June 09, 2018 - 11:53 am:

These brakes are self-energizing since the brake band anchor/pivot is all the way to the end of the shoe. When the brakes are applied while the car is moving forward the friction of the shoe and direction of rotation of the drum tends to "pull" the shoe tighter and makes less pedal pressure needed to stop. And since the pivot is at the rear you get the full braking effect of the entire length of the shoe.

When backing up the opposite is true. The direction of rotation of the drum tends to loosen the shoe instead of tightening the shoe. So more pedal pressure is needed to stop. In the case of these brakes or repro Rockies there will be very little braking ability in reverse.

Original Rockies and ACs as well as some other brakes, the brake band pivot lug is in the center/rear of the brake band. So when stopping going forward with original Rockies only the top half of the shoe is "self energizing" as the rotation of the drum is "pulling" the top half of the shoe tighter, but the bottom half is trying to loosen up or "trailing". So in effect the top half of the brake band is all that is stopping the car. The bottom half is helping very little. But when in reverse and backing up the opposite is in effect. The bottom half of the shoe becomes the "self energizing" section, and the top half is trailing and helping very little. But with the pivot in the middle like original Rockies have, the brakes work as well in reverse as they do going forward.

It is a trade off as to which style is best. Do you want very good brakes going forward and very little in reverse. ?? or do you want pretty good brakes going forward, and pretty good brakes going in reverse.

My personal choice is to use the repro "self-energizing" style brakes hooked to a "fourth" pedal in the floor. That way I get the full braking effect of the Rockies with no "fine line" of adjustment problems. The "Ford" brake and the Ford emergency brake are left as-is. That way I have the Ford brake for stopping in reverse or on hills. I end up with three "stand alone" brake systems on the car. But again, that is my "personal" choice.

Good luck with the brakes, and have fun and be safe.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Mark Gregush Portland Oregon on Saturday, June 09, 2018 - 12:49 pm:

Looking at the brakes shown, I am wondering if the rear part is more to keep the band centered on the drum. The thin rod and way it is set up, might work to some degree, but I am thinking the rod used to make it would be too small in diameter to stand up in the long run without bending.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Wayne Sheldon, Grass Valley, CA on Saturday, June 09, 2018 - 06:50 pm:

Mark G has the big point! The ONLY purpose of the rear anchor point is to keep the brake bands from chewing up the wheel spokes by vibrating and shaking out. It does not in any way add to the braking forward or reverse. These will brake very well in the forward direction, and poorly in reverse (may not be able to hold a car pointed up a steep hill). My preference (if operating these with the brake pedal?), is to use a fully independent emergency brake operated by the brake handle for reverse stops and hill holds. Personally, I do not like and do not recommend trying to set up the pedal to operate both the planetary drum and rear wheel drums. Years ago, I knew of a few people that wrecked their model Ts because they thought they had it properly adjusted. Fortunately, all three of them resulted in only minor damage to the car, and no injuries.

The best design rear outside brakes for a model T is to put the pivot anchor about one third of the way around the drum (lower part of the drum). That gives good energizing for forward without losing all the energizing in reverse. Unfortunately, nobody makes anything like those anymore.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Donnie Brown North Central Arkansas on Saturday, June 09, 2018 - 10:47 pm:

I agree with Mark and Wayne. The rear tab is only to keep the shoe centered left to right. It just acts as a guide.


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