I built two roof racks for my 1995 Volvo to carry a few sheets of plywood.
I want to build 4 'brackets with bolts' to bolt into the door frame. These brackets will hold the straps that secure the racks to the roof. There are threaded holes for this purpose in the upper section of the car frame inside each door. They were made to accomodate the OEM Volvo roof racks.
I measured the depth of each hole. It is approximately 3/4" deep. But I cannot figure out what the thread size is ?
Once I complete this I will gladly supply a photo of the racks and a list of materials so anyone can build their own.

 

NCdad: that'd be awesome. I wish you lived closer - I have access to a complete set of bolt size gauges - the kind you see hanging up at the hardware store that lets you figure out your bolt/thread size. Next time I am at my buddy's house, which should be tonight, ill check the holes for you and see if I can't get you the thread size.

Maybe someone else can chime in before me on this though. Either way, thanks in advance for posting up what you built - i cant wait to see it.

 

Thank you ! I think you will be pleasantly surprised to see the photos of the racks. They are made of wood and painted dark gray. They look good on top of the car too. They are super simple to build.

 

As promised: bolt specs

Those bolts are M6x1.0

Hope that helps!

 

Thank you ! I shall go over to LOWES to see if they have them. I shall get back to you.

 

I have added the photos of my home-built roof racks below. Here is a list of the items needed and the costs I paid. All braces, bolts, nuts and washers were bought at my local LOWES store.

• 2 pieces of wood: Approx 1" X2" by 48 inches long. I chose this length to carry 4'X8" sheets of plywood. I drilled two holes 1/2" wide to run the ropes though to tie down the plywood. I also drilled a 1"4 hole to mount the cross-bars to the roof mounts.
• 4 pieces of wood for roof mounts: Approx 2"X2" wide, 5 inches long. I put one set (2) 1" braces on each roof mount, Each pair of roof mounts is then bolted to the roof rack crossbar. Metal washers are sandwiched between the inside of the braces and the crossbars. Do not put them on the outside of the braces it might cause your bolt nuts to unscrew with use.
• Paint all wood pieces with a 'primer' first and then put one or two coats of a dark gray or black paint BEFORE ASSEMBLING THE ROOF RACKS.
• The bottom of the roof mounts will be in direct contact with your car paint surface. I glued some rubber shelf material to this to prevent marring and scratching he paint. You can substitute something better.
• I used 4 braces: 1"X1/2" and 4 bolts: metric size, M6 X 1.00 X 16MM long to bolt the crossbars to the roof. You can bolt these braces to the upper door frame of the car.
• I tied down the crossbars to the door frame braces with 1/4" nylon cord. This is OK, but I am looking for a better material such as a nylon or metal belt strap as a permanent solution. I don't want to tie and untie each cord every time I install and remove the roof racks. The cord I used had a 110 lb. strength.
• Here is a list of the metal parts you need they are all sold in the Hardware section of LOWES, aisle 12 in my store:

8 braces: 1"X1/2" sold on packets of 4 each with wood screws, cost is $1.97 per packet. You need two packets. They also sell the same braces in packets of 2 or 3 each. Stay away from these - it just drives up the cost. You need four braces for the roof racks and four for the door frames.
4 bolts with 4 nuts included: 1/4" X 2 inches long, the cost is $1.18 per packet. You need one packet.
8 washers: for the 1/4" bolts, cost 9 cents each. The store clerk can help you find them.
4 metric bolts: The have a hexagon head and screw into your door from - one for each door frame, cost $ .92 cents each. These bolt in the braces to your door frame.
NOTE: all braces come set like an L shape - at a 45 degree angle. This is fine for the roof racks but you will have to expand that angle for the braces bolted into the door frame so it does not scratch the paint on your roof. Just turn them over on a concrete walkway and tap out the angle with a hammer until they are opened up to a 65 or 70 degree angle.

I give special thank to forum member IBIFIED for providing the correct dimensions for the door frame bolts. His assistance was crucial to my success.
Also remember the Volvo owner's manual states the Maximum carrying capacity for the roof is 220 lbs. I intend to carry far less weight with mine.
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Hey, glad I could be of assistance. that looks pretty good!

 

I have driven with my home made roof racks since Sept. 13. I did not notice any wind resistance when driving up to 60 mph with the empty racks. I did load a sheet of plywood on them and did note some wind resistance at 40 MPH. I will use these for hauling one or two sheets of plywood. I may, one day load an 8 ft. boat (weight 50 lbs.) on them. I have two recommendations for anyone who builds these roof racks:
1) They are suitable for light loads only. Although Volvo states the roof can bear up to 220 lbs., I would not dream of putting this much weight on them.
2) Until I find and install nylon straps to secure the racks to the door frames, I will continue to drive only at speeds of 40 MPH or less. I am presently securing the racks to the car with nylon rope. I am not satisfied with this.

 

"Although Volvo states the roof can bear up to 220 lbs., I would not dream of putting this much weight on them"

Few questions -- I have the euro-style rails, and my Owner's Book says roof rails are rated for 100 lbs. Can you explain this difference?

I am in the midst of adding 2 roof cargo boxes on my Volvo. I will take some photos on the weekend and post them for feedback / critique.

The combined load on the roof rails will be around 200 lbs.

Should I worry about collapse at the roof-to-rail attachment points? Uplift?

How much would you guesstimate the mpg will drop?

 

Hello Henry10,
The answer seems obvious to me. Your roof racks state their maximum capacity is 100 lbs. This is their limit. My Volvo manual states the maximum weight you should put on the roof is 220 lbs. So for instance, if you had roof racks that would hold 500 lbs. -- Volvo states not to put more than 200 lbs on the roof. That is the way I interpret it. The roof racks I made for my car are to carry a couple of sheets of plywood. I have no intention of anything much heavier. I have no idea how my roof racks affect my gas mileage as my average trip length with a load is less than two miles.
There are other posts in this forum discussing roof racks. I recommend that you do a 'search'. I had lots of stuff bookmarked, but my previous computer was infected with a virus. I no longer have them.

 

I did look at my Owner's Manual -- it specifies 220 lbs for the roof carrying capacity, with OEM roof rails. I have the OEM roof rails. I am not sure where I saw the 100 lbs capacity. I will do some more searching this weekend. Plus I will take some photos.

I ran a search in this Forum and Matthew's Volvo. I did not find any info on MPG with rooftop cargo carriers.

I am driving from NYC to Iowa for Thanksgiving week, at about 700 lbs payload (people and cargo). This represents 75% of the capacity per the Book (total of 940 lbs for my 95 Turbo Wagon). At a ratio of .053 Power/weight ratio, there should be no problem on the car's ability to haul a$$. In comparison, I was running at about .036 Ratio with my E-150 Ford Conversion Van.

Aerodynamically speaking, roof carriers will add about 30% to my frontage envelope, which is a lot.

Due to my roof cargo carriers, I expect about 4-5 mpg penalty to my 24 mpg avg highway.

We'll see.

 

Henry: that sounds about right. Let us know what you find.

 

I hope I am not right -- at 20 mpg super unleaded, it would actually cost the same $ amount in gas as if I was going in with my E-150, 4.6L Ford Conversion van (14 mpg city, 18 mpg highway). With a lot more comfort in the Van!!!

We'll see. I should be able to have both boxes installed by Sunday and will make a highway run test for about 100 miles.

 

Between Bday parties and shopping, and my new radiator leaking, I did not have time to install the rooftop cargo carriers this weekend. Weather was about 65 F and I did 2nd coat of black flat paint.

The 850 Turbo Wagon will have 2 rooftop carriers (see attached photos) -- one for the luggage and the other one for gear, such as tools, bicycle spare tires, beach umbrellas, beach chairs, etc, i.e. dirty stuff. I don't need the rear one until the spring, but I will install it now (Nov).

Why 2? It just simply there is not enough room in 1 carrier for both functions. I don't like to use the trunk for storage: a- I want to use the trunk inside my Wagon for those rest naps; b- I will be installing a 4-bike rack on a rear hitch which will make access awkward.

The Front Carrier (# 1) is a Sears 15 cu. ft. Carrier, white color, now painted black. I got it for free since the previous owner had lost the keys. I will be installing a padlock-type key myself. This Carrier opens from the side.

The Rear Carrier (# 2) is about 12 cu. ft, 44" wide, 18" deep and 24" high, purchased at Target for about $ 35, dark purple color, which I painted black. This Carrier opens from the rear / top.

Carrier 1 will take the brunt of the wind forces. It is designed for that purpose. However the rear one is a Patio Storage Box, which I will be reinforcing. They will installed back to back, about 1" away from each other. Carrier 1 (about 36" wide) will need cross bars since rails are 41" apart. I found some nice XC90 cross bars for $ 20. Carrier 2 is 44" wide and spans across the OEM roof rails, i.e. will not need cross bars, which is good since it somewhat equalizes the height between the two (Carrier # 1 is 18" high, # 2 is 24" high).

Both Carriers will be attached to the roof cross bars / rails with U-bolts.

I painted them flat black paint; should I have used a smoother paint for better aerodynamic drag?

The 850 Wagon has some nice features that allow this add-on:

1- The roof are is pretty large and flat.
2- Roof carrying capacity is 220 lbs. I happened to have the OEM Eurorails (which measure approx 41" center-to-center away from each other).
3- Car is low enough to be able to stand on the bumper and access the Carrier. This is especially important for the Rear Carrier, which opens from the top. Although I am 6'1" I can barely reach the bottom of it.

 

Finished everything by 6:30 pm. They actually do not look too bad. I will take photos of the complete install tomorrow in daylight. I already took photos of reinforcements for Carrier 2.

Went tonight for a test drive, mainly to check Carriers for any rattling, and wind noise. No rattling, everything seems tight. However drove for about 2-3 miles at 75 mph and noticed wind noise when going over 65-70 mph. For speeds less, tire/car wind noise seems to beat out the Roof carriers. This evening it was windy out, so maybe that added. I checked everything at the end, and both Carriers are tight. Distance was not long enough to calculate mpg difference. MPG test will be Sunday on 100 miles trip.

My best friend -- bicycle tubes. I will explain that tomorrow.

 

I used cut-up bicycle tubes to separate everything, Carriers from cross-bars/rails, U-bolts, etc. This rubber is extremely strong, absorbs shocks/movement of different parts. Besides, it also prevents squeaking that tend to develop.

20 mile highway-Test (70-75 mph), empty run: results are not good. If you are following this -- I said that I am not reinforcing Carrier # 1, Sears-brand. I thought I didn't have too. I used to have a similar Sears Carrier on my previous SUV and it held up pretty good. But that was a different / later model. The one I am using now is very unstable; it is flapping 2-3 inches up and down at the front. This concerns me greatly, especially the uplift. This flapping makes the car bounce around a little (suspension is all new). I need to do something to make it stable, not sure yet. However, there is no movement on the attachments I made; connections Carrier-Cross Bars, and Cross Bars-Roof Rails are tight.

Carrier # 2 (Patio Storage Box from Target, reinforced DIY) did not move at all. No vibrations, nothing. LMAO. This carrier is 4" wider on each side than the Front Carrier. and as you can see from photos, it's walls are vertical, like a brick. I may need to do something on these sides to help it aerodynamically.

MPG -- Bad news, lost 4 mpg average. On 74/75 mph I averaged 20 mpg over 20 miles. On the way back, at 70 mph I averaged 22 mpg. On 65 MPH highways, I like to go 74 mph. On Sunday I will make a 100 miles test, this time fully loaded.

 

Photos of reinforcements (with explanation)...

 

Photos of both Carriers installed on the car....

 

Alternative:

Carrier mounted on a rear hitch. 60" wide x 24" high" x 24" deep. Bicycle rack can be installed on top of this box.

Hitch's connections to the chassis would need to be reinforced.

Benefit: no aerodynamic drag.

Disadvantage: this will enlarge cars footprint by about 30", not good for parking in the City. Plus lights/ license plate carrier would need to be installed on the Carrier.

 

Henry10,
I would be afraid to drive your car, as set up with all that stuff, at 75 MPH. True, I started this thread with my home-made roof racks. They were intended to carry light, low profile loads only, at considerably lower speeds. I also installed a trailer hitch on my 95 GLT for bulkier and heavier stuff. I suggest you consider that option too. Consider the installing a trailer hitch and renting a trailer.
You discuss aerodynamics and wind resistance as it will affect your car going straight down a highway, but you should also consider other scenarios too. What will happen to your ability to stop if you have to brake at 75 MPH ? With all that stuff piled on top of the roof how will it affect your ability to make a controlled stop ? What if you are braking in a curved road ? Could this arraingement be too top heavy and affect the balance? How will strong side winds affect your ability to control your car. The 850 is a beautiful car, but it is also quite flat sided and more susceptible to cross winds than more aerodynamically designed cars - like my son's Saturn SL1. With all that stuff stacked so high you will be more susceptible to cross winds.
I suggest you consider renting a trailer, or possibly rent a larger new vehicle that will easily accommodate you, your passengers and all of the cargo. I believe these are safer options.