WINDSCREENS - Maurice Ford
FRAMES -There are two types of windscreen frame:
a) Early type with externally visible channel fixing screws and thumb screw type hood retainers and
b) Late type with internal channel fixings and 'clip type' hood rail fasteners. The hood locating pegs, are, incidentally, farther apart than the earlier type so that an early hood will not fit a late car and vice versa. The late type frame has the uprights set farther out the bottom, relative to the mounting feet, by a good inch and at a different angle so that at the top it is only 3/4 inch or so wider than the early frame. This late frame is also higher by about 1/2 inch.
GLASS - Glass for the early 'small' frame still available as Pilkingtons still have the jigs. Their agents (AutoWindscreens) will obtain one from them at around £200. The late type is NOT available off the shelf and Pilkington/Triplex do not recognise it as being made by them. The early type screen will not fit! The only way is to have one cut from a modem equivalent by a competent screen company (I acquired mine from Tamworth Autoscreens who were very helpful) and let them have the frame so that they can fit it. Do not get the screen before you decide on the seals. See below.
SEALS - For early screens the seal is no longer available. Since the glass does not enter very far into the channel the seal is rather odd. It can be made up by using Edgware seal 319 and bonding/glueing L3 to its base.
For the late screen you have a choice - either make up a seal as above and have the screen cut to fit this or cut the screen to fit deep into the channel with comers notched to clear the frame fixing brackets (as MGB) and use rubber seal 325 bedded in silicon.
This last method looks a lot neater but there is a snag. The glass will not stand any serious frame deflection during fitting - I suspect that this is the reason why the original method was used during production, particularly since the method of fixing the screen frame to the body is not very clever. When fitting it is essential that packers are used between the screen frame feet and the body to ensure that these fit exactly each side and will tighten down without fouling the scuttle as it rises up over the dash. If it fouls here it will push the frame outwards at the bottom and try to stretch the glass. Failure to be diligent when fitting the screen and frame to the body will cause you another trip to the screen maker.
I hope that the above is of some use to other Doretti owners but if anyone needs further info they are welcome to contact me.