MIDAS RollCage

[Rich]

That's a very clean looking Midas you have there Dave. Did the cage eventually come with full back stays?

Rich

[d.woodspeed]

Hi Rich.
Yes, she does'nt look too bad now. Years of neglect and lack of use/stored outside had taken its toll on the gelcoat. Much polishing with a slightly abrasive polish, (3-M finesse-it) has got rid of most of the "milky/white marks," some keep coming back, but continuing selective re-polishing seems to gradually remove them. Good thing
the gelcoat is pretty thick!! Good old Harold!
I have'nt ordered the rear support struts, hence the stubs for later fitting. When I finally get the hoop properly mounted, I can then accurately measure for the struts. That's the plan when I've got some time, (and renewed motivation!!).
Cheers, Dave.

[rocketron]

Dear Dave, looking at the pic of your cage, at the area where your right ear is, it seems to me that the vertical part of the hoop "leans" backwards, allowing quite a bend. For hillclimb/sprints under MSA rules, in classes where cage/ROPS is compulsory, under K1.1.3 and K1.3.1 "the vertical part of the main rollbar must be as straight as possible and as close as possible to the interior contour of the bodyshell". In my opinion, a kink to allow the top part of the hoop to lean back, as I see in your case, is not acceptable.
In your defence, current Prodrive Imprezas main hoops do have a sort of "lean back", but they are triangulated back to the main vertical part.
Prodrive cages, somewhere, have had testing, stress calculations with drawings for each part, verified and accepted by the MSA. This verification is important. Your cage manufacturer should present you with a copy. For Competition car log booking, verification must be seen at inspection. Whatever anyone tells you, "home-made", back of fag packet cages are not acceptable. Material used is also important, cold drawn seamless carbon tube. Steel reinforcement of the bodyshell at each area of cage "feet". Many logbook applicants' vehicles fail here.
Correct cages and their correct fitting is not easy. I logbook very many comp cars every year and have done for a long time. I'm more than willing to give help, please ask myself or your local scrutineer before commitment.

Please understand that I am not being negative but trying to help you sort out probs before they happen. It pains me greatly when competitors vehicles fail logbooking inspection, or even scrutineering, over an anomaly after spending so much time, effort and expense. "Let's get it right, right from the start". I'd hate for you to get it wrong

I really look forward to see you and the Midas sprinting, a great car in a great sport.

[d.woodspeed]

Hi Ron, thanks for your advice, I guess you're an MSA scrutineer!? I apologise if I've created confusion, let me clarify, the pic shows the hoop loosely sitting in the car, its not fixed yet, and is actually leaning forward, propped up by a toolbox! When bolted in, it will be totally vertical at 90 degrees to floor. I do appreciate the finer points of roll cage fitting, having built a few rally carsover the years, and getting them log booked etc.

I've still got my Comp. Licence and value my head (!), so I do refer to my current copy of the 'blue book' when relevant!

I appreciate your interest, and hope I can ask your advice via this forum on technical matters in the future. Actually, what are your thoughts on mounting main cage legs in a fibreglass shell? Obviously if it was steel, one would weld 3mm x min. 120 cm2 reinforcement plates to the shell floor. K 1.3.2 makes no comment on none-steel shells. My plan is to use a 4 to 5mm thick plate of suitable size to spread the load, both on top of floor and under, which will obviously be held in place by the cage mounting bolts. I don't think laminating the plates to the floor would make any difference, do you?

Look forward to your comments,
Regards, Dave.

[rocketron]

dear dave, yes, you guess right, a scrute of some thirty odd years. Sorry for slow reply, computers are not my forte and you may contact whenever and how often you like. Alternatively, my tel no. is 01492 641 688, evenings till 10.30. Am in discussions with Technical, your proposed mountings seem ok but we're considering an alternative, so will reply to you soon.
Another point of recent concern, cages were designed originally for older cars. Consider windscreen angles of Mk1 cortina (30*) to some modern Peugeots at about 60* from vertical. We're looking at possible mandatory "pitprop" tubes from top of windscreen pillar to floor for some installations: might be an idea to compare how Midas windscreen angle is to the two examples given. Am fairly certain you'll be ok without pitprop.
Speak to you soon Best regards, Ron

[Stuart]

It wouldn't half make getting in and out difficult if you had to fit a pitprop

[rocketron]

True, it could be difficult, but it depends on each installation. As I said, it's being considered for cases of greater windscreen rake angles. I'm of the opinion a Midas would be ok. Pitprops are not yet mandatory. Nowhere does it say they are to be vertical. It is to triangulate off the front hoop along windscreen pillar.
MSA rules K1.3.2 states clearly ".....steel reinforcing plate...to be welded to the bodyshell". So in your case, glass in the plate and it would be acceptable, quote Michael Duncan MSA Tech. Rep. This is for all mounting feet including backstays (K 1.3.3).

If the fitting is difficult, the MSA will not give you a "waiver". Your choice is simple: modify the car, get a different car or do something else.

I draw your attention to K1.5.1+2, Does your cage manufacturer supply you with a MSA issued ROPS certificate. This is IMPORTANT (not all scrutes are conveniently blind!). Also K1.6.1 and FIA 253-17D, minimum allowable door aperture dimensions. Don't forget doorbars (K1.3.5.(b) But not so low as to be ineffective). Roughly, can you get out and clear of car in less than 15secs. Joking asides, fire induced impetus etc. blah-di-blah, feet get trapped around steering wheel, seat edges and cage front hoop, while your arse is on the floor and the door is whacking your expensive helmet. The seconds disappear fast enough without panic setting in.

Without taking tape to car, I think it's possible to fit a "normal" cage to a Midas, and I think you should give it a go. But, please, heed the rules and sort the probs first. The rest is then donkey work!!

REgards,Ron

[d.woodspeed]

Ron, thanks for that, I can now formulate a plan!

I know what you mean about the 15 second rule, my son rallies a rapid Ctroen Saxo VTS, which has a substantial "multi whatsit" triangulated, welded in cage, and that's a real pain(!), to negotiate when exiting, without banging your head, knee or elbow, and it does'nt do much for your dignity either! It really is a case of 'climbing' in and out, but it can be done in less than 15 seconds!

In comparison, my old historic rally Cortina, with a simple 6 point cage and single door bars was almost "limousine like" when entering or exiting!!

Regards, Dave.

[rocketron]

Dear Dave, for your information. The MSA has recently announced that for a front leg of a ROPS which has more than one bend, this also includes the "slight "pull"!" which was sort of allowed last year, and after a recent lengthy technical/elegibility tribunal, that a straight "pitprop" MUST be welded with its connections within 100mm at the top of the turn of the ROPS at the top windscreen and the mounting at the floor.
Also, if the forward floor mounting is aft of a verical line drawn through the ROPS bend at the lower edge of the windscreen, then a "pitprop" MUST be fitted.
As this is a safety issue implementation is immediate. (I daresay, without prejudice, that cars already logbooked will have a couple of months "grace". Cars about to be logbooked will not.)
For a front ROPS leg with one bend, at the correct location (base of windscreen) and the mounting foot directly below, or forward, of this bend, a pitprop is not required.

[d.woodspeed]

Ron, thanks for that info, I can now proceed without any worries, and I should not need a pitprop either!

While we're talking Blue book regs, what are your thoughts on fuel tanks/fillers and liquid proof bulkheads in relation to the Midas bodyshell? Obviously the tank
is under the floor, but the filler pipe in the rear wing passes through the rear of the car interior. Is there any sensible alternative to making and fitting a "tunnel"
around the pipe, i.e. can I wrap it in something, say a larger diameter flexible pipe sealed at each end, to the rear inner wing and the floor?

I look forward to your comments, thanks, Dave.