Roll over frame design.

[paulhumphries]

I've some underbody work to do on both my Minor and A35 so a roll over frame is going to be useful.
I've numerous lengths of scaffolding sized tube and the matching die for my bender.
I'm thinking along the lines of bending a big "J" (without the top bar of course) and then using KeeKlamps to hold things together. In the past I've found that additional collars can be clamped on if necesary to give extra support to the fitting or if the galv is ground off then welds can secure onto the poles.

Question therefore is it worth locating the frame onto both sides / all four hubs or just one side / two hubs adequate (I think I'd prefer both sides) ?

Paul Humphries

[8009STEVE]

is it worth locating the frame onto both sides / all four hubs or just one side / two hubs

You can only roll the car on one side at a time, so I would suggest only on one side.

[MoggyTech]

The Pro Rollers are two hub fixing so that should be enough. Fixing to all four hubs, might provide a bit more rigidity though, handy if you are chopping out large sections.

[jonathon]

Just be aware that if rolling a complete car on just the hubs that this puts a huge strain in bearings and bushes. The shell will also experience loads in directions not encountered before plus the suspension mounts are heavily loaded. In effect the whole shell can be compromised if there is a large amount of welding to do. I'd suggest that you measure with the car on the ground then check when its on the jig.
We would only normally use a roll over if the car was bare, or the repair panels already tacked into position and the car rolled for final seam welding. Even then measuring is key to retaining an uncompromised chassis.

[paulhumphries]

I should add that both my cars (Minor & A35) are basically solid and not in need of major structual work.
I want to be able to do small amounts of repairs but more important be able to properly clean the underside and paint / rustproof.

Paul Humphries

[rayofleamington]

I've got a Grumpy's car roller and wish I'd bought it a decade earlier. It can make the work much much quicker as working standing up is more efficient than when squeezed under a car.

I fully agree about being careful when a shell is badly rotten, but whether it's on a roller or on the wheels if the shell strength is not there, it can distort whilst you're trying to repair it.
A general rule is to limit the amount of sructure you remove in one go, and if an area is very weak, strengthen it up before removing too much.

With a 2 hub mounted roller, most of the stress is applied to one side of the shell and you're working on the unloaded side (unless you're daft). This limits the problems you'll get in to on a saloon shell unless it's very rotten.
If the shell is a basket case then extra (triangulated) bracing is needed across the door apertures and across between each side - however if the shell is that bad, you need to think if it's really worth the effort!!

When I've done this with a shell in need of a lot of work then removing as much weight as practical is a good idea (engine, gearbox etc...). Additional to this I've added extra jacks to distribute the load on the shell to a number of places.
Depending on what you're doing it can be very useful to leave the doors in place. They are darn heavy things, but if they close well before you start work, this is a sign that the shell is ok and you can monitor door gaps to make double and tripple sure before seam welding in at the door posts and sills.

You can't see much of the rolling frame here, but the bottom part of the J's is visible:

[bmcecosse]

Ray - some more pics would be welcome! Was it easy enough to roll the car over - I'm guessing not a single handed job ? Is the frame made from bent angle iron - or square section tube - can't see from the pic!

[Matt]

I borrowed this roller... I used an engine crane to lift the car because I was on my own and it had all the drive train, but it could probably be done with 3/4 people

its made out of 2x1 sort of size box section of around 1.5-2mm wall thickness. The hub mounts are welded on to a triangle welded on the bend

[rayofleamington]

It's square section tube and has been formed in to a J shape.
It's got a pillar to munt the plate for the hub and a simple clamp arrangement to mount the joining bar (a bar runs from the top of the front J to the top of the rear J). The top of the J goes to a few inches above the bottom of the side windows. When the car is rolled on to the side of the J it only goes approx 80° not 90° and with the large bend radius in the J, the load is not over centre (i.e. with the feet removed it would roll back by itself)

A Minor with engine can be rolled with 4 people. A bare shell with 3 people. However, the initial lift is much easier if the car is jacked up to start the roll as much as possible.

[Sidney'61]

Just looking at what Kim did in his restoration, he's gone for the cheaper option and just rolled the car onto some tyres, how safe is this?
would you suggest it?
http://www.mmoc.org.uk/index.php?name=P ... 93&start=0

[rayofleamington]

I wouldn't suggest it, as I'd prefer to have something a bit more foolproof to stop the car from rolling too far or coming back down on top of you whilst you are doing heavy jobs like removing suspension etc...
However that's what people used to do for decades before car rollers came on DIY the market.

If you want to work on the car with the front and rear suspension removed, the options start to become very limited.

[bmcecosse]

Thanks Ray - I had forgotten about this thread.
Q from me - when the frame is first fitted to the car - is the inner leg of the J then sitting on the ground reaching under the car exactly at the centre line of the car?

[Matt]

this pic might help people

[bmcecosse]

The pics are a great help Matt - but if you could maybe run a tape over the CURVED section of that frame - not including the straight bit now touching the grass - that would help lots. I need to know if 42" of angle iron would do it!! Mainly because - I have an 84" length of good new thick angle, and lots of shorter lengths which could make the other bits! Scrapyard challenge coming up.

[paulhumphries]

Just looking at what Kim did in his restoration, he's gone for the cheaper option and just rolled the car onto some tyres, how safe is this?
would you suggest it?
http://www.mmoc.org.uk/index.php?name=P ... 93&start=0

Nearly 30 years ago I did that with a Riley Elf.
Admittly I'd stripped it down to a bare shell first but had trouble stopping it trying to roll back so used rope anchored to lumps of angle iron hammered into the ground like tent guy ropes.
I've be very reluctant to do it again when you can get / make a roller that is a lot safer.

Paul Humphries

[paulk]

http://cgi.ebay.co.uk/Mk1-Mk2-escort-Mk ... dZViewItem

Has anyone tried this type of Jig?

Apart from having to get the bumper bars up to 2.5-3ft high it would seem a more stable structure. but not sure a Minors bumper supports would be up to it?
I've got to roll Milly and I'm 1/2 way to having built a J type jig but just wondered if this type would be more stable.

[bmcecosse]

Aye - the shell would need to be pretty solid for the bumper supports to take the weight! Although mine look 'ok' - I wouldn't trust them on that spit. Maybe not too bad with just a bare shell.
Are you willing to share any dimensions of your J type frame with me Paul ?? I'm keen to make one - just need some sizes.

[paulk]

I've used 2no 10' lengths of scaffold tube.

To bend these I used the forklift . I parked the forklift on one end of each tube and with a bar under the other end of the scafold tube (but across the forks tips) this meant as I lifted the forks up each tube was gently bent around the tyre on each side of the forklift. It's given a radius of about 1ft but not crushed the pipes.

The hub plates were 150mm by 10mm thick plate which I punched and plasma'd out to the right shape. Cross beams need adding but I thought just kee klamps or scaffold clamps would do that.

It's not done yet because I need to fit some feet to lock the whole thing when it's on it's side. Matt's had a go with it but without the feet it doesn't yet work.

[Matt]

BMC... I cant do any measurements because the frame went back to Ray...

Paul... it might be possible to roll Millie, and chock the frame with a pair of axle stands under your "hub plates"

[paulk]

I'm in the process of sorting out some swing down stops, Matt.

But will probably use axle stands and some big bits of wood as well JUST to be sure