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Flat towing brake mechanism [message #190958] Wed, 21 November 2012 08:59 Go to next message
mschultz is currently offline  mschultz   United States
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Happy Thanksgiving to All
When we begin traveling in earnest next year, flat towing a vehicle is being considered. Our best choice of what we have is a rear wheel drive 122 Volvo, 2400 lbs. The big question is braking. Currently the GMC has a Electric Trailer Brake Control. The cost of the ready made devices are a little over the top, going for $1000 generally. I am currently looking at linear actuators, like the one shown at Grainger seen here: http://www.grainger.com/Grainger/WARNER-LINEAR-Linear-Actuator-18G681?Pid=search

This is 2 inch stroke, 100 lbs. 12 VDC and 4 seconds to reach full stroke.
There is also one shown in a 4 inch stroke, 100 lbs. 12 VDC and 8 seconds to reach full stroke.

My question is what effective control would the brake control have over this device? How does the varying degree of braking that is set at the control effect the electric magnetic trailer brakes? The linear actuator I believe is motor driven and the shaft is extended via a screw device. The brake control may not be effective in controlling with any degree of sensitivity on this device. If anyone has some other thoughts on the subject, I would like to hear them. Like most questions on this forum, the topic has been dealt with before and I am grateful for receiving a small taste of the combined experience, knowledge and recommendations of this group. Thanks.
Re: [GMCnet] Flat towing brake mechanism [message #190962 is a reply to message #190958] Wed, 21 November 2012 09:33 Go to previous messageGo to next message
sgltrac is currently offline  sgltrac   United States
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Check out the inertia system ken h uses. Pretty simple yet effective

Sully
77 royale
Seattle

Sent from my iPhone

On Nov 21, 2012, at 6:59 AM, Michael Schultz <mschultz2002@chartermi.net> wrote:

>
>
> Happy Thanksgiving to All
> When we begin traveling in earnest next year, flat towing a vehicle is being considered. Our best choice of what we have is a rear wheel drive 122 Volvo, 2400 lbs. The big question is braking. Currently the GMC has a Electric Trailer Brake Control. The cost of the ready made devices are a little over the top, going for $1000 generally. I am currently looking at linear actuators, like the one shown at Grainger seen here: http://www.grainger.com/Grainger/WARNER-LINEAR-Linear-Actuator-18G681?Pid=search
>
> This is 2 inch stroke, 100 lbs. 12 VDC and 4 seconds to reach full stroke.
> There is also one shown in a 4 inch stroke, 100 lbs. 12 VDC and 8 seconds to reach full stroke.
>
> My question is what effective control would the brake control have over this device? How does the varying degree of braking that is set at the control effect the electric magnetic trailer brakes? The linear actuator I believe is motor driven and the shaft is extended via a screw device. The brake control may not be effective in controlling with any degree of sensitivity on this device. If anyone has some other thoughts on the subject, I would like to hear them. Like most questions on this forum, the topic has been dealt with before and I am grateful for receiving a small taste of the combined experience, knowledge and recommendations of this group. Thanks.
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Sully 77 Royale basket case. Future motorhome land speed record holder(bucket list) Seattle, Wa.
Re: Flat towing brake mechanism [message #190966 is a reply to message #190958] Wed, 21 November 2012 09:54 Go to previous messageGo to next message
Rick Williams is currently offline  Rick Williams   United States
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Micheal

I have the Unified Tow Brake system. It works well but as you say, it is pricey. I tow a Jeep Wrangler. The Unified system uses a large 12 volt solenoid to pull in the brake pedal. The level of current to the solenoid is set by two conditions. It is proportional to the level set by the driver ( a 0-9 scale) and is also proportional to the level of braking that is taking place. It uses a pendulum to determine the amount of braking just as the trailer brake controller does. So it is somewhat similar to the electric brake system used on trailers. Trailer brake controllers vary the amount of current to the electric brakes based on the same parameters. Level set by the driver and level of braking taking place based on the position of the pendulum. The pendulum is why the brake controllers must be mounted within a range of positions. You might be able to adapt a large solenoid (perhaps buy a replacement from Unified)and have it controlled by the brake controller. The Unified system also uses a vacuum pump to replenish vacuum in the brake booster to make pulling the pedal easier. It comes on when brakes are applied.
I do not think that a linear actuator will work. The response time would be too slow and it is probably not made for varying supply current. Even if it could use varying current, that would only make it slower to respond.
I hope this helps.

Rick



Rick Williams
Bliss, Michigan
1978 Eleganza II
Re: [GMCnet] Flat towing brake mechanism [message #190968 is a reply to message #190962] Wed, 21 November 2012 10:13 Go to previous messageGo to next message
kerry pinkerton is currently offline  kerry pinkerton   United States
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sgltrac wrote on Wed, 21 November 2012 09:33

Check out the inertia system ken h uses. Pretty simple yet effective ...




Amazing http://www.gmcmhphotos.com/photos/data/5153/5_Toad_Brake.jpg

http://www.gmcmhphotos.com/photos/data/5153/5_Toad_Brake.jpg


Kerry Pinkerton - North Alabama Had 5 over the years. Currently have a '06 Fleetwood Discovery 39L
Re: Flat towing brake mechanism [message #190969 is a reply to message #190958] Wed, 21 November 2012 10:23 Go to previous messageGo to next message
SteveW is currently offline  SteveW   United States
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Outstanding !!

That is one of the simplest and most clever contraptions that I've seen in a long, long time.

I'm actually searching for toad towing options - including braking systems. Perfect timing for this thread.

Ken - May I use your Intellectual Property and build a similar system ??

Thanks,
Steve W
Southern California



Steve W 1973 : 23' Southern California
Re: [GMCnet] Flat towing brake mechanism [message #190973 is a reply to message #190968] Wed, 21 November 2012 10:52 Go to previous messageGo to next message
mike miller   United States
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Kerry Pinkerton wrote on Wed, 21 November 2012 08:13

sgltrac wrote on Wed, 21 November 2012 09:33

Check out the inertia system ken h uses. Pretty simple yet effective ...



Amazing http://www.gmcmhphotos.com/photos/data/5153/5_Toad_Brake.jpg

http://www.gmcmhphotos.com/photos/data/5153/5_Toad_Brake.jpg


Keep in mind Ken posted the photo on April 1st. (2009)

<http://www.gmcmhphotos.com/photos/5-toad-brake/p28985-the-ultimate-proportio.html>



Mike Miller -- Hillsboro, OR -- on the Black list
(#2)`78 23' Birchaven Rear Bath -- (#3)`77 23' Birchaven Side Bath
More Sidekicks than GMC's and a late model Malibu called 'Boo' http://m000035.blogspot.com
Re: [GMCnet] Flat towing brake mechanism [message #190976 is a reply to message #190969] Wed, 21 November 2012 10:59 Go to previous messageGo to next message
Ken Henderson is currently offline  Ken Henderson   United States
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Permission granted with two conditions:

1. You have to be able to decipher the design date shown in the
comments: 090401

2. You report road test results here.

Ken H.

On Wed, Nov 21, 2012 at 11:23 AM, Steve Weinstock wrote:

>
>
> Outstanding !!
>
> That is one of the simplest and most clever contraptions that I've seen in
> a long, long time.
>
> I'm actually searching for toad towing options - including braking
> systems. Perfect timing for this thread.
>
> Ken - May I use your Intellectual Property and build a similar system ??
>
> Thanks,
> Steve W
> Southern California
>
>
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: [GMCnet] Flat towing brake mechanism [message #190977 is a reply to message #190973] Wed, 21 November 2012 11:09 Go to previous messageGo to next message
C Boyd is currently offline  C Boyd   United States
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You know it really did take a genius to come up with this.. put it on tracks to keep from sliding sideways. add a storage tank & elec vacuum pump for brake booster & power it off the tow vehicle.







Mike Miller wrote on Wed, 21 November 2012 11:52

Kerry Pinkerton wrote on Wed, 21 November 2012 08:13

sgltrac wrote on Wed, 21 November 2012 09:33

Check out the inertia system ken h uses. Pretty simple yet effective ...



Amazing http://www.gmcmhphotos.com/photos/data/5153/5_Toad_Brake.jpg

http://www.gmcmhphotos.com/photos/data/5153/5_Toad_Brake.jpg


Keep in mind Ken posted the photo on April 1st. (2009)

<http://www.gmcmhphotos.com/photos/5-toad-brake/p28985-the-ultimate-proportio.html>





C. Boyd
76 Crestmont
East Tennessee
Re: Flat towing brake mechanism [message #190983 is a reply to message #190958] Wed, 21 November 2012 11:51 Go to previous messageGo to next message
SteveW is currently offline  SteveW   United States
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Thanks Ken !!

Yea... April Fools... but I actually might mess around with it a bit. I think it's very very clever.

I'd build some wheels / tracks to keep it in line. I'll probably build a slight uphill ramp so that lifting off the gas to coast wont cause enough of a momentum change to apply brakes. And I'll rig up some sort of indicator system so that I can observe when brakes are actually applied... Maybe some bungie cords to adjust sensitivity.

Don't hold your breath for road test results though. I've got way too many incomplete projects underway - so I'll try to get some finished before I start this one Smile

Steve W



Steve W 1973 : 23' Southern California
Re: Flat towing brake mechanism [message #190987 is a reply to message #190983] Wed, 21 November 2012 12:28 Go to previous messageGo to next message
mike miller   United States
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SteveW wrote on Wed, 21 November 2012 09:51

Thanks Ken !!

Yea... April Fools... but I actually might mess around with it a bit. I think it's very very clever.

I'd build some ...


To test the concept, just drive along and reach down and unlatch the slide adjuster on your seat. Then hold on and press on the brake.

Be advised this is NOT recommended at speeds more than a few mph.

I did it by accident once at about 10 mph. It is amassing how much a little inertia will do....

Not something I'd do again. Rolling Eyes


Mike Miller -- Hillsboro, OR -- on the Black list
(#2)`78 23' Birchaven Rear Bath -- (#3)`77 23' Birchaven Side Bath
More Sidekicks than GMC's and a late model Malibu called 'Boo' http://m000035.blogspot.com

[Updated on: Wed, 21 November 2012 12:59]

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Re: Flat towing brake mechanism [message #190988 is a reply to message #190983] Wed, 21 November 2012 12:36 Go to previous messageGo to next message
rcjordan   United States
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>track
>uphill ramp
>some sort of indicator system
>bungie cords to adjust sensitivity
>storage tank & elec vacuum pump for brake booster
>power it off the tow vehicle

My thoughts exactly. With the addition of a ramp and some spring tension to dampen the action and return it to home position I think it's worth a try. For older, lighter toads the brake booster might not even be necessary. As for the indicator system, it seems that a wireless trailer light controller in the toad could send a signal forward to the GMC cabin.


SOLD 77 Royale Coachmen Side Dry Bath
76 Birchaven Coachmen Side Wet Bath
76 Eleganza
Elizabeth City, NC
Re: [GMCnet] Flat towing brake mechanism [message #190993 is a reply to message #190977] Wed, 21 November 2012 13:24 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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C Boyd wrote on Wed, 21 November 2012 11:09

You know it really did take a genius to come up with this.. put it on tracks to keep from sliding sideways. add a storage tank & elec vacuum pump for brake booster & power it off the tow vehicle.

He did not show you the crane it takes to lift that thing out of there when you want to drive the car. I wonder what that thing weighs?

I also wonder what happens when you are traveling down hill. Ken probably has figured out all of that out as this is not a new design. He developed it several years ago.

Actually I think it is a great idea.

I wonder where Ken got that rail. Have you ever seen the movie October Sky?




Mike Miller wrote on Wed, 21 November 2012 11:52

Kerry Pinkerton wrote on Wed, 21 November 2012 08:13

sgltrac wrote on Wed, 21 November 2012 09:33

Check out the inertia system ken h uses. Pretty simple yet effective ...



Amazing http://www.gmcmhphotos.com/photos/data/5153/5_Toad_Brake.jpg

http://www.gmcmhphotos.com/photos/data/5153/5_Toad_Brake.jpg


Keep in mind Ken posted the photo on April 1st. (2009)

<http://www.gmcmhphotos.com/photos/5-toad-brake/p28985-the-ultimate-proportio.html>







Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: [GMCnet] Flat towing brake mechanism [message #190995 is a reply to message #190993] Wed, 21 November 2012 13:37 Go to previous messageGo to next message
rcjordan   United States
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>what happens when you are traveling down hill.

Having once seen a trailer trying to jack-knife around the truck that was towing it while coming down the side of Mt. Afton's Rockfish Gap, I might be willing to drag the toad's brakes on a steep downgrade.


This looks interesting, but I don't see a price anywhere

http://www.towbrake.com/mmaster.html


SOLD 77 Royale Coachmen Side Dry Bath
76 Birchaven Coachmen Side Wet Bath
76 Eleganza
Elizabeth City, NC
Re: Flat towing brake mechanism [message #190996 is a reply to message #190958] Wed, 21 November 2012 13:54 Go to previous messageGo to next message
kerry pinkerton is currently offline  kerry pinkerton   United States
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Both my trailers have electric brakes that are controlled by a $100 brake controller. Variable pressure, adjustable from tow vehicle. I'd THINK that the electric mechanism inside the brake drum could be modified to push and release the brake pedal in the same way. The brakes will WORK without the booster. It just takes a lot more force on the pedal.

Kerry Pinkerton - North Alabama Had 5 over the years. Currently have a '06 Fleetwood Discovery 39L
Re: Flat towing brake mechanism [message #190998 is a reply to message #190996] Wed, 21 November 2012 14:11 Go to previous messageGo to next message
rcjordan   United States
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Here's a mechanical brake system that fits in the receiver. While the theory seems good, I'd have some concerns about syncing the maximum distance the arm can travel with the the total distance the toad's pedal can move.

http://www.readybrake.com/brake-systems.html


SOLD 77 Royale Coachmen Side Dry Bath
76 Birchaven Coachmen Side Wet Bath
76 Eleganza
Elizabeth City, NC
Re: [GMCnet] Flat towing brake mechanism [message #191001 is a reply to message #190995] Wed, 21 November 2012 15:07 Go to previous messageGo to next message
kerry pinkerton is currently offline  kerry pinkerton   United States
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rcjordan wrote on Wed, 21 November 2012 13:37

>

This looks interesting, but I don't see a price anywhere

http://www.towbrake.com/mmaster.html


Sent an inquiry and the salesguy called me. $920 delivered, Thanksgiving special. $1050 normally. Comes with a dedicated controller that has adjustable inertia switches that determine how much pressure is applied. Plus a manual override if you want to drag your brakes, a breakaway switch and alarm. Sits in the towd floor and you pull two pins to remove. It runs off the towd battery and you charge the towd from the tow vehicle while driving.


Kerry Pinkerton - North Alabama Had 5 over the years. Currently have a '06 Fleetwood Discovery 39L

[Updated on: Wed, 21 November 2012 15:11]

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Re: [GMCnet] Flat towing brake mechanism [message #191002 is a reply to message #190993] Wed, 21 November 2012 15:11 Go to previous messageGo to next message
LYNN L   United States
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Ken also posted a braking system for a toad that used a vacumm actuator. It inspired me to build my own system and it works very well. Since the GMC has onboard air I choose an air operated system using an electrical solenoid and adjustable regulator to control the brake pedals applied pressure. It also uses a JC4 GM vacumm pump with a quick dump valve to release the brake pedal quickly. It ended up costing me about $375.00, but it peforms as well as a factory system and has all the same features such as a break away sw and an emergency air reserve.

Lynn L 76 Eleganza Cad.500 Pearland TX.

[Updated on: Wed, 21 November 2012 15:21]

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Disregard this [message #191004 is a reply to message #190993] Wed, 21 November 2012 15:15 Go to previous messageGo to next message
LYNN L   United States
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Registered: March 2005
Location: Pearland TX.
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Senior Member
No Message Body

[Updated on: Wed, 21 November 2012 15:17]

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Re: [GMCnet] Flat towing brake mechanism [message #191009 is a reply to message #191001] Wed, 21 November 2012 16:52 Go to previous messageGo to next message
shawnee is currently offline  shawnee   United States
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Kerry Pinkerton wrote on Wed, 21 November 2012 16:07

rcjordan wrote on Wed, 21 November 2012 13:37

>

This looks interesting, but I don't see a price anywhere

http://www.towbrake.com/mmaster.html


Sent an inquiry and the salesguy called me. $920 delivered, Thanksgiving special. $1050 normally. Comes with a dedicated controller that has adjustable inertia switches that determine how much pressure is applied. Plus a manual override if you want to drag your brakes, a breakaway switch and alarm. Sits in the towd floor and you pull two pins to remove. It runs off the towd battery and you charge the towd from the tow vehicle while driving.



I tow a 2010 Honda Fit and it makes a good light tow. I also use a SMI braking system. It has a control module that fits under the driver's seat and supplies vacuum to a cylinder that is mounted on the brake arm with a wire that is anchored to the floor board. It also has a vacuum line going to the vacuum line to the engine vacuum line and a check valve going to the brake booster. It operates by radio control to the unit in the motorhome with a transmitter and receiver and senses how hard the brake is being applied. It has a power switch in the motorhome and car so it can be turned on or off. This is about 5 years old but works very well. The newer unit operates with a pressure cylinder but works in a similar fashion. I understand the price is about $800 but it is very reliable.


Gene Dotson
74 Canyonlands
www.bdub.net/Motorhome_Enhancements New Windows and Aluminum Radiators
Re: [GMCnet] Flat towing brake mechanism [message #191015 is a reply to message #190998] Wed, 21 November 2012 17:28 Go to previous message
jhbridges is currently offline  jhbridges   United States
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The toadstone is so light it doesn't need brakes... but if I ever do add them, I will likely use surge brakes off a trailer.  The plumbing hadn't ought to be too convoluted.
 
--johnny
'76 23' trandmode norris
'76 palm beach.

From: RC Jordan <rc@rcjordan.com>
To: gmclist@temp.gmcnet.org
Sent: Wednesday, November 21, 2012 3:11 PM
Subject: Re: [GMCnet] Flat towing brake mechanism



Here's a mechanical brake system that fits in the receiver.  While the theory seems good, I'd have some concerns about syncing the maximum distance the arm can travel with the the total distance the toad's pedal can move.

http://www.readybrake.com/brake-systems.html
--
77 Royale "Retro Chic" (still in Florida)
Elizabeth City, NC
1 hour south of Norfolk VA
1 hour west of Kitty Hawk, NC
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Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons. Braselton, Ga. I forgive them all, save those who hurt the dogs. They must answer to me in hell
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