James Cook Forum

Hello I wanted to replace the webasto with a midi-heiki for a long time. I have seen with great interest what has been done by ixcebichee, Jurgen and a few others. I have been living in an apartment for some time and no longer have a workshop at my disposal nor a router.
So I tried to imagine, from their experience, another way of proceeding.
In fact, I did a little the reverse. They worked a POM plate to give it the shape of the roof while keeping the superior planarity. I took a wooden plate that I plasticized and I put it on the roof filling the voids between the roof and the plate with polyester mastic and I then secured the whole thing to the roof by a strip of roving.
So I started by buying a 840 x 620 x10 marine plywood plate in which I cut a 702 x 502 hole in its center and covered with 2 layers of glass mat embedded in the polyester resin Then, in another 5 mm thick plywood plate, the size of the initial interior cover covered with gray canvas (I no longer have the exact size) I made a 702 x 502 round in its center and I also laminated it with roving and resin (it's not useful). It will be our internal framework. The dimension of the cutout of the midi-heiki being less in width than the original one, I glued two plywood boards in 5 mm resinated to the roving in order to have in width 702 mm ... When installing the midi-heiki, it must be centered between the 2 slides of the interior curtain. But, as it is very difficult to take interior measurements to transfer them to the exterior, I used the interior frame that I had made, holding it in its place. [
I was able to position the outer frame from there...

I continue
Once everything was in place I cut the end of the roof using a Dremmel (about 35mm by 500 towards the front) then I filled all the gaps between the roof and the plate with polyester putty ( green). I made it penetrate well on and on the sides. Then, I put a strip of roving embedded in resin on each side. The roving starts from the top of the plate, to join the roof on approximately 20mm in order to ensure the tightness as well as the solidarity with the roof. After this operation, the plate and the roof become one. Then came a good 2 hours of sanding ... to make everything smooth. I then applied a layer of finishing gelcoat (white) on the roof + plate assembly. Unfortunately it is not the right color. But I'll fix it later. Mounting the heiki afterwards is child's play. I slipped some leftover 10mm plywood under each window clamp and used my own 4mm screws (longer) so that they were threaded through and screwed to the plate.
I then screwed the inner plate and put the inner cover of the heiki.

Après 2 mois d'utilisation je suis très content de cette réalisation. Il n'y a évidemment pas d'eau à rentrer car une fois achevée et le roving en place cela devient un construction monobloc le toit et le support de la midi-heiki ne faisant plus qu'un ensemble compact complètement "plastifié". Même en roulant vite il n'y a pas plus de bruit qu'avec le webasto. L'impression de luminosité est supérieure à celle donnée par le Webasto et les 3 niveaux d'ouverture sont très suffisants. J'ai choisi un système Heiki avec la barre car c'est moins fragile que le système à manivelle ou électrique. J'ai une mini-heiki dans la cuisine avec ce système et j'en suis très content; c'est une des raisons de mon choix. La mise en oeuvre de mon système m'a pris 5 jours (le plus long est d'attendre les phases de séchage de la résine) et ne nécessite pas d'outillage complexe. J'ai tout réalisé avec des contreplaqués de bois, du mat de verre, du roving, de la résine polyester, du mastic de carrossier polyester et du gel coat pour la couche de finition. L'outillage était une scie,une dremel, des pinceaux, un rouleau à laque pour le gel-coat, une ponceuse électrique et du papier de verre.
Une fois fini tout est fonctionnel comme avant; la midi-Heiki est entre les 2 rails du rideau et n'empêche pas son fonctionnement même s'il devient un peu inutile vu que la midi-heiki a son propre système d'occultation.Je n'ai qu'un regret c'est de na pas l'avoir fait plus tôt. La midi-heiki semble d'assez bonne qualité le seul reproche que l'on peut faire est que la visserie fournie est de très mauvaise qualité (les vis se cassent comme du verre). J'ai donc utilisé des vis achetées dans le commerce en inox.

After 2 months of use I am very happy with this achievement. There is obviously no water to enter because once completed and the roving in place it becomes a one-piece construction, the roof and the support of the midi-heiki becoming a compact whole completely "plasticized". Even when driving fast there is no more noise than with webasto. The impression of brightness is greater than that given by the Webasto and the 3 opening levels are very sufficient. I chose a Heiki system with the bar because it is less fragile than the crank or electric system. I have a mini-heiki in the kitchen with this system and I am very happy with it; this is one of the reasons for my choice. The implementation of my system took me 5 days (the longest is to wait for the drying phases of the resin) and does not require complex tools. I did everything with wood plywood, glass mat, roving, polyester resin, polyester bodybuilder's putty and gel coat for the topcoat. The tools were a saw, a dremel, brushes, a lacquer roller for the gel-coat, an electric sander and sandpaper.
Once finished everything is functional as before; the midi-Heiki is between the 2 rails of the curtain and does not prevent its operation even if it becomes a little useless since the midi-heiki has its own occultation system. I have only one regret that is not to have done it earlier. The midi-heiki seems to be of fairly good quality the only criticism that can be made is that the screws provided are of very poor quality (the screws break like glass). So I used commercially purchased stainless steel screws.

It's good to know that the roof is generally repairable! Congratulations on your work.

Seeing the picture of the roof I wondered whether there is any kind of spoiler or windguide in front of the Heki. For my James from 2004, there is one, although I think it is rather for keeping the water off the Heki while driving.

Best,
Kasimir