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chrisarella
04-23-2018, 08:44 PM
I hope this serves many builders for years to come.

Source (my Build site): Chris's Cobra Build Site - Chassis Dolly (http://cobra.chrisarella.com/chassis-dolly/)

Click here to download the PDF (http://cobra.chrisarella.com/wp-content/uploads/2018/04/Factory-Five-Roadster-MkIV-Chassis-Dolly-ChrisArella.pdf).

The finished product.

http://cobra.chrisarella.com/wp-content/uploads/2011/10/390680_10150492585101122_935367349_n.jpg


Tools



Drill / Screw Gun
Circular Saw
1/2″ Wrench or ratchet
Measuring Tape
Chisel
Rasp or Sander



Materials



(1) 2′ x 4′ x 1/2″ Plywood Sheet
(1) 2″ x 4″ (nominal) dimensional lumber, 8′ long
(1) 4″ x 4″ (nominal) dimensional lumber, 8′ long lumber
(1) 2″ x 6″ (nominal) dimensional lumber, 8′ long lumber
(16) 3/8″ x 3″ Lag Bolts
(16) 3/8″ Washers
(52) 2-1/2″ Coarse Drywall Screws
Heavy-duty casters (rated to 800 lbs. each; 2,400 lbs total capacity)
Low pile carpet, enough to yield (4) 3-1/2″ x 12″ strips
Paint (optional)



Steps

Squarely cut your 4″ x 4″ lumber into (2) 44″ lengths.

Squarely cut your 2″ x 4″ lumber into (2) 21″ length pieces.

Cut each 21″ piece with a 45° angle inward at both ends of each piece, so that their final length is 21″ at the longest point.

Cut your remaining 2″ x 4″ lumber into (4) 9″ lengths with a 45° angle at one end of each piece.

Squarely cut your 2″ x 6″ lumber into (1) 60″ length, and (4) 9″ lengths.

84850
On each of your 4″ x 4″ x 44″ lumber, place marks 19-1/2″ from each end so that they are 5-1/2″ apart at the center.

Set a depth of 1-1/2″ on your circular saw, and cut grooves across the face of your 4×4 within the 5-1/2″ wide area at the center.


http://cobra.chrisarella.com/wp-content/uploads/2011/12/Factory-Five-Roadster-MkIV-Chassis-Dolly-ChrisArella-02.png

Chisel out the grooves and sand down the rough pieces to smooth out the opening flat as needed.

If you are going to paint your dolly, now is the time to do it while you have everything apart. Once dry, you can assemble it.

Using (4) 2-1/2″ drywall screws, join a 2″ x 4″ x 9″ piece flush to one end of your 4″ x 4″ x 44″ piece on the top, so that the 45° cut is angled inward.

Repeat joining another 2″ x 4″ x 9″ piece flush to the other end of your 4″ x 4″ x 44″ piece on the top so that the 45° cut is angled inward.

Using (4) 2-1/2″ drywall screws, join a 2″ x 6″ x 9″ piece flush to one end of your 4″ x 4″ x 44″ piece on the bottom.

http://cobra.chrisarella.com/wp-content/uploads/2018/04/Factory-Five-Roadster-MkIV-Chassis-Dolly-ChrisArella-03.png


Repeat joining another 2″ x 6″ x 9″ piece flush to the other end of your 4″ x 4″ x 44″ piece on the bottom. You now have the front and rear bases complete.


http://cobra.chrisarella.com/wp-content/uploads/2018/04/Factory-Five-Roadster-MkIV-Chassis-Dolly-ChrisArella-04.png


Flip the front and rear bases upside-down to expose the slot in the bottom.

Slide the 2″ x 6″ x 60″ cross brace into the slots, to join the front and rear platforms and screw them together using (2) 2-1/2″ Drywall screws at each end.

Cut (2) triangular pieces of plywood such that two legs are approximately 24″ long and the other is 18 long.


http://cobra.chrisarella.com/wp-content/uploads/2018/04/Factory-Five-Roadster-MkIV-Chassis-Dolly-ChrisArella-05.png


Join a triangular piece of plywood to each end of your dolly, such that the short end follows the long, outside edge of the base. Screw down each piece of plywood using (5) 2-1/2″ drywall screws. Make sure to put (3) into the base and (2) into the 2″ x 6″ x 60″ cross brace. This will help to keep the dolly from torquing when rolling your chassis around the shop.

Using your lag bolts, fasten your casters to each corner of your dolly.

Flip it over.

In the recesses where the chassis will sit, apply some liquid nails and tack your carpet strips in place. This is to protect the bottom of the chassis from getting scratched. Let dry completely per the directions on the Liquid Nails.

Here is a picture from the PDF if you want to just print this out for a one-page plan:


http://cobra.chrisarella.com/wp-content/uploads/2011/12/Factory-Five-Roadster-MkIV-Chassis-Dolly-ChrisArella-00.png

Enjoy!


History

Years ago when I first ordered my roadster, I built a chassis dolly in support of building my Roadster. Like everything I do, I researched the heck out of it before engineering it as best I could and within reason. It needed to:


be able to support the weight of a finished vehicle
be easy to build
be easy to roll around my garage
be able to be locked in place
allow room to work underneath comfortably
have very little restrictions on my ability to run brakes, fuel, and electric


My car has been on this chassis since December of 2011 and I have been very happy with the dolly for 6 years. Life took me in many different directions since receiving my car that put the project on hold for years but I am finally getting back to it.

There have been several on here that have used the photos of my completed dolly for their own but I never took the time to publish any documentation on mine. Well, sorry it took so long.

*Note: These plan are provided as general guidelines to help you build a chassis dolly to support the building of a Factory Five Racing Mark IV Roadster. No warranty is provided, and you assume all risks.

mosh1999
04-23-2018, 09:40 PM
Thanks Chris!

doddmoore
04-23-2018, 10:55 PM
THANK YOU! I think I asked on Facebook as well. I really appreciate this.

phileas_fogg
04-24-2018, 08:06 AM
I copied Chris's design 2 years ago (thanks Chris!), but added some height under the wheels. When rolling over the lip of my garage, one of the "stilts" snapped off the dolly. So if you choose to add some height, do this:

https://farm5.staticflickr.com/4306/36290037675_66771f07d6_k.jpg (https://flic.kr/p/XhPVSK)IMG_0874 (https://flic.kr/p/XhPVSK) by jhsitton (https://www.flickr.com/photos/91016165@N07/), on Flickr

Do NOT do this:

https://farm5.staticflickr.com/4293/36290039715_af7d4d8c17_k.jpg (https://flic.kr/p/XhPWtV)IMG_0871 (https://flic.kr/p/XhPWtV) by jhsitton (https://www.flickr.com/photos/91016165@N07/), on Flickr

Or you'll end up with this:

https://farm5.staticflickr.com/4294/36290038725_8abc14b97c_k.jpg (https://flic.kr/p/XhPWbR)IMG_0872_2 (https://flic.kr/p/XhPWbR) by jhsitton (https://www.flickr.com/photos/91016165@N07/), on Flickr


John

toadster
11-19-2019, 02:04 PM
love this writeup!

has anyone done a body dolly with an open middle? i.e. you can drop in the engine/trans without hitting a center piece?

sorry for my poor artwork, but seems that if you have 2 supports - 1 under each rail, you'd free up the center...

117786

phileas_fogg
11-19-2019, 04:45 PM
Two thoughts. First, I'd be concerned about the dolly holding the total weight of the car. Do some math, check the specs on your casters, & you'll figure out if it'll work or not. Second, I suspect the two longitudinal pieces would hinder access to the underside of the car.

But since I haven't done it, I truthfully say one way or another. :p


John

chrisarella
11-19-2019, 07:50 PM
Thanks for the kudos toadster.

I'm not an engineer but I believe the horizontal sheer tolerance of a single 4x4 is well above the 800-lb rated casters I used, so in theory this dolly should be able to support the combined tolerance of the casters: 3,200-lbs. Plenty of head-room for the weight of a roadster. The bigger question is how in the world you'd get a fully built roadster off the dolly at that point. ;)

toadster
11-20-2019, 12:12 AM
Thanks for the kudos toadster.

I'm not an engineer but I believe the horizontal sheer tolerance of a single 4x4 is well above the 800-lb rated casters I used, so in theory this dolly should be able to support the combined tolerance of the casters: 3,200-lbs. Plenty of head-room for the weight of a roadster. The bigger question is how in the world you'd get a fully built roadster off the dolly at that point. ;)

Id assume a floor jack would work - right? ;)

chrisarella
11-20-2019, 02:58 PM
Id assume a floor jack would work - right? ;)
would probably need one on each side to get it up evenly so you could slide it out from under the chassis.

delta0014
11-20-2019, 03:15 PM
I built one with just a 2x12 going down the center. To put the engine in, I put it on jack stands to move the dolly out of the way. I put the front jackstands as high as they’d go and the rear ones low.
After the engine I put it back on the dolly, haven’t had any problems with it supporting the weight. Kept jack stands under the frame for a bit just in case.
Pretty easy with a jack to get it on and off the dolly, as long as you have jack stands.

phileas_fogg
11-20-2019, 04:44 PM
Yep. Lift either front or rear onto jack stands, then the other end. Nerve wracking, but you get used to the idea once you realize you have no choice.

Good call on having the chassis on stands for the engine install. As it is, I had to jockey the front stands around a bit to figure out where to place them so I could move the legs of the engine hoist where they needed to be. I don't believe I could have gotten the hoist in place if the chassis was on the dolly.


John

B Campbell
08-07-2021, 09:46 PM
Thanks Chris. I modified the plans to fit a Gen 3 Coupe. 20.5" center to center on the frame rails and 65" total length 5" longer than the Roadster dolly

jrcuz
08-08-2021, 06:25 AM
I used your plans 5 years ago Chris and it worked out perfect. I passed my dolly to another builder at least 2 years ago and he liked it too.
JR

PMD24
10-08-2024, 03:02 PM
I'm unclear why a dolly is needed. In the build school I attended we used jack stands start to finish. Is it to move the car during the build if its in the way of other activity?

rich grsc
10-08-2024, 03:47 PM
No, a dolly is not needed

BRRT
10-08-2024, 04:09 PM
Rich is correct, a dolly is not necessary. I built one, and my frame is currently setting on it. It has been very handy to move the frame around in my limited space. It is nice to be able to move the frame and clean under it.
A lot of drill chips are created during the build.
So, not necessary, but for me it has been pretty handy.

Mike.Bray
10-08-2024, 04:48 PM
If I build another roadster I will build another dolly, it was really convenient being able to move it around. I would not build another body buck, I would just use four hooks under the wheelwell openings. I didn't see any value in the buck at all.

PMD24
10-12-2024, 05:47 PM
Thanks to all for feedback on my question. I'm going to build one. Murphy's law says if I place it on jack stands, the next day I'm going to need to move it to free up the space to work on something else that breaks down!

BRRT
10-13-2024, 05:51 PM
Thanks to all for feedback on my question. I'm going to build one. Murphy's law says if I place it on jack stands, the next day I'm going to need to move it to free up the space to work on something else that breaks down!

Good move

MaxVmo
10-14-2024, 03:21 AM
There are also builders that give dollys away after they are done using them. I have one in AZ.