Hitch rack and rear window screws

D

dave silva

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Oct 2, 2009
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Planning to make the coach a Vacation cruiser with no toad.

So i'm looking for a 72" hitch basket for the bikes and the Blackstone. 60" are cheap and plentiful but that extra foot is harder to find, might
have to get it fabricated.

I'm also looking at the massive phillips head screws that hold in the rear panel - how thick is the aluminum on the other side?

I'm thinking i could replace the screws with tiedown eyes, they would still hold the panel in but also give me something to attach to.

The outer ones would have a cable/turnbuckle to stabilize the hitch basket and the middle ones would take tie downs to hold the load.

Any fatal flaw in this plan?
--
Dave & Ellen Silva
Hertford, NC

74 Birchaven, 1-ton and other stuff
 
On the rack, I would take a 60" one and add 6" tp each end.

If you are talking about the 30 or so screws that hold the rear panel on, they are not bedded in aluminum. It is fairly thin fiber glass back there.
You would have to go inside and remove the inner panel. Then reinforce the areas where you want to change screws.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
> If you are talking about the 30 or so screws that hold the rear panel on, they are not bedded in aluminum. It is fairly thin fiber glass back
> there. You would have to go inside and remove the inner panel. Then reinforce the areas where you want to change screws.

Wow, that's surprising. But i see where my ladder is mounted on a few small screw rather than the big one so i assume they went looking for some
frames to latch on to.

I'm relucant to make new holes in the skin but it would be worth it for the end result.
--
Dave & Ellen Silva
Hertford, NC

74 Birchaven, 1-ton and other stuff
 
Be very careful how you load the basket, putting a few pounds 6 feet behind
the rear bumper can mess up your center of gravity loading. Look at the
leaver from 6 feet behind the bumper to the center of your rear wheels. I
did not do the measurements but my ruff guess is one lb 6 feet back is
equivalent to adding three lbs to the tongue weight. Our coaches have a
limited tongue weight as it is.
Have you looked at towing a small trailer or adding a pod to the roof?

On Wed, Dec 16, 2020 at 7:55 AM dave silva via Gmclist <

> > If you are talking about the 30 or so screws that hold the rear panel
> on, they are not bedded in aluminum. It is fairly thin fiber glass back
> > there. You would have to go inside and remove the inner panel. Then
> reinforce the areas where you want to change screws.
>
>
> Wow, that's surprising. But i see where my ladder is mounted on a few
> small screw rather than the big one so i assume they went looking for some
> frames to latch on to.
>
> I'm relucant to make new holes in the skin but it would be worth it for
> the end result.
> --
> Dave & Ellen Silva
> Hertford, NC
>
> 74 Birchaven, 1-ton and other stuff
>
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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>

--

*John Phillips*
 
> Be very careful how you load the basket, putting a few pounds 6 feet behind
> the rear bumper can mess up your center of gravity loading. Look at the
> leaver from 6 feet behind the bumper to the center of your rear wheels. I
> did not do the measurements but my ruff guess is one lb 6 feet back is
> equivalent to adding three lbs to the tongue weight. Our coaches have a
> limited tongue weight as it is.
> Have you looked at towing a small trailer or adding a pod to the roof?

No, six feet behind would be problematic. I'm thinking 30" deep by 7 feet wide. The weight would be on the hitch but I can stiffen it laterally by
adding some hardware to the bumper.

But i'm still pondering how to tap into the aluminum at the top so i can run tiedowns vertically.
--
Dave & Ellen Silva
Hertford, NC

74 Birchaven, 1-ton and other stuff
 
Thank you for the clarification. Sorry I misunderstood.

On Wed, Dec 16, 2020 at 9:09 AM dave silva via Gmclist <

> > Be very careful how you load the basket, putting a few pounds 6 feet
> behind
> > the rear bumper can mess up your center of gravity loading. Look at the
> > leaver from 6 feet behind the bumper to the center of your rear wheels. I
> > did not do the measurements but my ruff guess is one lb 6 feet back is
> > equivalent to adding three lbs to the tongue weight. Our coaches have a
> > limited tongue weight as it is.
> > Have you looked at towing a small trailer or adding a pod to the roof?
>
>
> No, six feet behind would be problematic. I'm thinking 30" deep by 7 feet
> wide. The weight would be on the hitch but I can stiffen it laterally by
> adding some hardware to the bumper.
>
>
> But i'm still pondering how to tap into the aluminum at the top so i can
> run tiedowns vertically.
> --
> Dave & Ellen Silva
> Hertford, NC
>
> 74 Birchaven, 1-ton and other stuff
>
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>

--

*John Phillips*
 
Dave,

If it has a Blain through the bumper hitch, don't worry about it. We came back from out last excursion with a gifted "Back Porch" that had about
3~400 pounds on it. The compressor ran as expected, but it did not affect the handling that I could tell and I was very worried about that at the
time.

Matt
--
Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
 
> Dave,
>
> If it has a Blain through the bumper hitch
> Matt

Huh?

I am not too worried but i put a large camping box on a heavy duty hitch basket on an Explorer. It worked great but the side to side motion of the
load warped the basket a bit.

And of course, i want the option to overload should i spot a 455 at a yard sale in COlorado for $100 or a vintage Chambers Range (390 LB)

But i really want to work out how to attach cargo straps to the top.

Where can i find frame under the ski?

Hah, i wonder if my stud finder would work ?

--
Dave & Ellen Silva
Hertford, NC

74 Birchaven, 1-ton and other stuff
 
Sir, this might help?

https://www.gmcmi.com/wp-content/uploads/2014/05/Transmode-Body-Builders-manual.pdf

> > Dave,
> >
> > If it has a Blain through the bumper hitch
> > Matt
>
> Huh?
>
> I am not too worried but i put a large camping box on a heavy duty hitch basket on an Explorer. It worked great but the side to side motion of
> the load warped the basket a bit.
>
> And of course, i want the option to overload should i spot a 455 at a yard sale in COlorado for $100 or a vintage Chambers Range (390 LB)
>
> But i really want to work out how to attach cargo straps to the top.
>
> Where can i find frame under the ski?
>
> Hah, i wonder if my stud finder would work ?

--
C. Boyd
76 Crestmont
East Tennessee
 
Being very familiar with the structure at the back of a GMC I'd personally be very careful loading it with much weight. I know people have and do
carry bikes and other things on the hitch but the frame really isn't built to carry much of a load. Hanging a 455 off the rear could be a real killer,
something I'd never recomend.
JMO, Hal
--
"I enjoy talking to you. Your mind appeals to me. It resembles my own mind, except you happen to be insane."

1977 Royale 101348,

1977 Royale 101586, Diesel powered,

1974 Eagle Bus 45',w/slideout,

Rio Rancho, NM
 
> Hanging a 455 off the rear could be a real killer, something I'd never recomend.
> JMO, Hal

Well it's certainly not my plan but now i'm curious, what kind of tongue weight can it handle?

--
Dave & Ellen Silva
Hertford, NC

74 Birchaven, 1-ton and other stuff
 
23’ that you have should handle more then a 26’

But the body is flimsy as heck. Even if you catch aluminum. Build and use the frame/rack for support.

Side to side rock can easily solved with a brace on hitch. Most carriers dont have that.
--
Jon Roche
75 palm beach
EBL EFI, manny headers, Micro Level, rebuilt most of coach now.
St. Cloud, MN
http://lqqkatjon.blogspot.com/
 
> > Hanging a 455 off the rear could be a real killer, something I'd never recomend.
> > JMO, Hal
>
> Well it's certainly not my plan but now i'm curious, what kind of tongue weight can it handle?


This thread is getting a bit muddy.

I think a 6 or 7 foot wide hitch rack, about 30" deep, would be very handy. The receiver would take the weight pretty well (about 300lb loaded) But
the load all on the center would be sloppy.

The fix for that would be to attach the bumper bolts to the hitch to stabilize it.


Meanwhile, the best way to lash four bikes, folding chairs, a Blackstone and whatnot would be tiedowns from the top. They would not carry a big
load.

So if i can locate a stringer i could drill and tap into it and maybe add some epoxy on the surface.

--
Dave & Ellen Silva
Hertford, NC

74 Birchaven, 1-ton and other stuff
 
WHat i really need to know is; how thick is the material on the last aluminum stringer at the roof ?
--
Dave & Ellen Silva
Hertford, NC

74 Birchaven, 1-ton and other stuff
 
I have been working on an aluminum component to be riveted into my coach's skin. I have measured and the skin on the side by the door is 1/16"
(0.063") AA6063. We tested the skin with an Niton fluorescence X-Ray gun. Don't know for certain if the roof is the same, but I think it is. Hope
this helps.

BTW - I removed all 32 of the Hi-Lo screws and removed the back panel. They are a thread designed for screwing directly into soft material and mount
into the SMC rear cap. I would not recommend putting any other loads into them. I suppose you could drill a couple out oversize, use structural
adhesive to hold a threaded insert in, and use a machine threaded fastener.
--
78 Eleganza II
Stock 403 w/ Carb
Single Cinnebar bags
6kW Onan
 
> the skin on the side by the door is 1/16" (0.063") AA6063.
>
> BTW - I removed all 32 of the Hi-Lo screws and removed the back panel. They are a thread designed for screwing directly into soft material and
> mount into the SMC rear cap. I would not recommend putting any other loads into them. I suppose you could drill a couple out oversize, use
> structural adhesive to hold a threaded insert in, and use a machine threaded fastener.

No. definitely not attaching anything to the composite material.

But at the top there is an aluminum stringer of some sort. I'm guessing .100" thick? .120" ?

Once I have that info I can figure what to mount and what load it can take.

--
Dave & Ellen Silva
Hertford, NC

74 Birchaven, 1-ton and other stuff
 
Let me point out something. The body and the frame are not directly connected. There are rubber isolators between the two and the body moves some on
the frame.

I routinely carry a 350 pound motorcycle and have carried a 450 pound motorcycle on a hitch mounted carrier that I made years ago. I tie down the
motorcycle diagonally from the handle bars down diagonally to frame piece behind the bumper. I also do the same from the back of the motorcycle to
the same horizontal part of the frame behind the bumper NOT THE BODY. I have it figured out where to park the motorcycle on the carrier so the weight
is almost evenly balanced left to right of the coach. I do not remember the total length of the carrier but it is probably 7'3" to 7'6" wide across
the rear of the coach.

Driving I never know it is back there. Every so often I look in the mirror to make sure it is still back there because I can not tell he difference
when it is on or not. I can just see the top of the motorcycle handle bars and windshield out the rear window with my inside mirror.

One other thing I did to the drawbar portion of the carrier. Rather that us a standard hitch pin I drilled the hole in the drawbar under size and
tapped it for a 5/8" grade 8 bolts. After inserting the drawbar in the receiver, I install the two bolts through the receiver pin holes horizontally
and tighten them securely. Now there is no wiggle at all between the receiver and the drawbar.

All of this assumes that you have a quality Blaine Merrell Receiver Hitch and the drawbar is thick enough to take threading.

As I was typing the I just thought of something. If you already have a pin and the holes in the receiver and carrier, you could drill and tap two
more holes vertically in the receiver and drawbar, leave the pin installed as normal, and still install the bolts too. I did not think about that over
15 years ago when I made that carrier.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
> Let me point out something. The body and the frame are not directly connected. There are rubber isolators between the two and the body moves
> some on the frame.
>
> I routinely carry a 350 pound motorcycle and have carried a 450 pound motorcycle on a hitch mounted carrier that I made years ago. I tie down the
> motorcycle diagonally from the handle bars down diagonally to frame piece behind the bumper.

Great info on the body/frame relationship.

THe problem i am trying to solve is to have convenient reliable tie down for a random pile of crap. A rack that is purpose built for something like a
motorcycle is pretty straight forward.

I want straps coming down from the top for the more random load- bike, folding chairs, a second spare, a wicker love seat that somebody "had to have"

So are you saying that if i tap the skin to get to the stringer i will have the frame flexing independent of the skin and maybe elongate the holes and
create cracks?

Well, just another engineering problem to solve- i'll figure it out.

The current challenge is knowing exactly where the stringer is and how thick is the material.

--
Dave & Ellen Silva
Hertford, NC

74 Birchaven, 1-ton and other stuff
 
I regularly run with either a 375 lb scooter or a 60" wide cargo rack
(sometimes with random crap on it, up to about 275lbs?). In both cases -
the rack connects to my under bumper 2" receiver. I use a square U bolt
to help reduce "wobble". About two years ago we re-positioned the
receiver - it had a definite downward tilt and fixing that helped with
clearance in & out of driveways...

I only strap the loads down to the racks - I've never strapped to
anything on the bumper or frame. I've done 5000+ miles with the scooter
back there.

When I've got the scooter on - I *definitely* feel the weight hanging
off the back!  I always like the handling improvement when I have
nothing back there...

Rob
Victoria, BC
76 Royale - Rear Twins/Dry Bath

> Great info on the body/frame relationship.
> THe problem i am trying to solve is to have convenient reliable tie down for a random pile of crap. A rack that is purpose built for something like a
> motorcycle is pretty straight forward.
>
>
> I want straps coming down from the top for the more random load- bike, folding chairs, a second spare, a wicker love seat that somebody "had to have"
>
>
> So are you saying that if i tap the skin to get to the stringer i will have the frame flexing independent of the skin and maybe elongate the holes and
> create cracks?
>
> Well, just another engineering problem to solve- i'll figure it out.
>
> The current challenge is knowing exactly where the stringer is and how thick is the material.
 
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