[Tresjolie]

Thanks for your help. I’ve cut the EPDM. Doing the trim tomorrow. It’s painfully slow maybe it’s nerves.
I haven’t got the order of sticking down yet
Tony did you glue the Correx in place before glueing the EPDM to it.
I’m thinking maybe:
1 fill all gaps round ABS.
2 glue Correx in place.
3 fit trim to EPDM
4 glue EPDM to Correx

Is that the order you used?

[Tresjolie]

Thanks Bill and Pam

I have all the bits and bobs. A mixture of your solution and Tony’s (Martrim and Mathys, Correx and EPDM)

Having things delivered during lockdown means they have to be left for 72 hours.

I am trying to make the back edge of the Correx not interfere with blind track. The next step will be to get all the bits in place before glueing.

You said that you used a tin of Mathys Easifil to glue the shelf to the ABS. In another post you said you used Mathys Elastofill. I bought 4 tubes of Elastofill. I have not bought the Easifil as I missed the note in your first post. Do I need this?

I was hoping that the Elastofill could be used to completely seal the gaps around the ABS and then across the raised areas to glue down the Correx. Did you fill the voids with Elastofill then use the Easifil across the raised areas? This is the part of the job that really worries me. It has to be right first time.

Tom

[Tresjolie]

Cheers Tony.
Correx cut. EPDM arriving tomorrow

[Tresjolie]

Hi Tony

I’ve ordered the Correx (4mm). Can you please confirm that you used 6mm EDPM. Also in what order did you proceed i.e. cut Correx, Fix Correx in place, stick EDPM etc. Or did you put it all together then fix it in place ?

Thanks in advance

Tom

[Tresjolie]

Template no 4. 2 Correx and 2 Ply. This is the second ply. I tried to remove the side bars. Discretion is the better part of valour so gave up. I cut the first ply in half then after some thought made the second 2mm Correx and finally the second ply which can be fitted by placing one side first. I’m not looking forward to doing it with all the mastic in place. Hopefully the 4mm Correx has a little flex in it.

Tom

[Tresjolie]

Thanks Barry

Looking at Tony’s photo he seems to have moved the horizontal rail back.

I’m doing the plywood template next. It was £20 for a large sheet enough to make 2 if necessary. I’ve cut a large rectangle containing the tracing. The plywood was a bit distorted so I’ve put weights on it to try and flatten it out also I can now measure the rectangle to get and idea of the size for the Correx order.

It still hasn’t rained since I started so can’t check the windscreen. Though I’m pretty sure it’s leaking.

Tom

[Tresjolie]

They are vertical blinds with horizontal movement. The 2 blinds pull across the cab and lock in the middle. Nothing in the Book so may have to play

Tom

[Tresjolie]

I cut a template from 2mm Correx. It’s quite flexible so could be made to fit. The UK comfort pack came with a horizontal Remis blind. I wonder if I will have to remove the blind to fit the shelf or cut the shelf into 2 pieces

Tom

[Tresjolie]

Fred! Excellent thought. I will have to ask that question. I suppose that Correx, being a ‘honeycomb’ construction won’t expand as much. Do you think the original wood shelf expanded and pulled the lower rim of the windscreen seal away when it contracted. The mastic under the seal had deteriorated. I can’t understand why these screens fail.

Barry! The wooden shelf was held in place by screws at the back and under the seal at the front with copious amounts of a rubber mastic and round the rim and across the middle ABS supports. The screws would not have added much strength to the overall construction. The mastic did not set completely hard so when the shelf was removed it came away with difficulty but looked like a rubber gasket. Initially when I started I thought it was a manufactured seal/gasket. The mastic was absorbed slightly by the ply and it adhered to the ABS but pulled away with effort leaving a clean surface. I want to use something similar so I have bought lots of the stuff Pam and Bill used and will play with that before applying.

Thank you both for your contributions.

Tom

[Tresjolie]

Also available in 4mm which would fit nicely with Tony’s design. One concern is plastic adhesion to metal

Tom

[Tresjolie]

Searching for plastic alternatives I found HPL

HPL is the abbreviation for High Pressure Laminate. HPL is made up of several layers that are compressed (laminated) under very high pressure. This creates a very dense, hard and form-retaining sheet (HPL).

The structure of the sheet
An HPL sheet consists of a wood fibre or paper core and two top layers. The core of the sheet consists of several layers of wood fibre and paper that are soaked with phenolic resin. During production, these layers are compressed under high pressure and at a high temperature. The resin that is used is a so-called thermoset. This means that the resin becomes hard under the influence of heat. By compressing, the layers are compacted and create a very dense and hard sheet. The top layers are so hard and dense that sunlight and moisture cannot penetrate into the sheet. In the first instance, HPL sheets were therefore developed as cladding material for outdoor use in residential and non-residential buildings, for example, maintenance-free exterior panels and plastic fascia boards.

Any thoughts on this. £46 for a 6mm sheet

[Tresjolie]

If water gets onto the ABS tray it will drip down from the heater duct into the cab when the van is parked uphill. This is the reason I removed the shelf.

The windscreen seal was replaced by National Windscreens 5 years ago so if it’s a leak I will ask them to reseal it before I replace the shelf. It hasn’t rained since I started this job.

I was worried that the MOT is due in May and that I would have to get everything back together before then but I may have some leeway with the virus allowing a 6 moth stay of MOT.

Tom

[Tresjolie]

I have done some research on the products:-

These are my notes so far (copied from websites)

Ply

1
Marine grade has no natural decay resistance. It has no chemicals added to enhance decay resistance, unless it has been subsequently pressure treated (= $$$). Marine grade has no special waterproofing in or on the wood, unless it has been added as a special feature.
 
If you don’t get the wood wet very often and if it’s sealed there’s no difference in performance indeed by using a different, less expensive grade and species with an exterior rating.

2
If you have a boat or are planning on building something that will be submerged in water, then marine plywood is what you’ll be working with. This type is a thicker material than regular plywood, comprised of about seven to 10 layers as opposed to three to five, with glue locking them all together. The adhesive in regular plywood will actually dissolve over time, causing the structure of the wood to break apart, but marine plywood is specially treated to withstand years in direct contact with water. By sealing this material, however, you can increase its overall lifespan. The information that follows will show you how to properly go about this project so you can get plenty of use out of this material for many years to come.

Sand the Surface
One of the things marine plywood has in common with other types is that you will always need to sand it down in order to stain, paint, or seal it. Go over both sides of the wood, as well as the edges, with 80-grit sandpaper by hand. Then, use a tack cloth to thoroughly clean up any dust you created during the process. You may even hose it down, but remember to allow it to dry completely before moving forward.

Apply the First Coat
Sealing marine plywood is a lot like sealing other types but it does differ slightly. In most cases, you would coat only one side and be done with it, but since marine plywood is going to be used underwater, everything has to be treated.

Dip a foam brush into the clear, penetrating epoxy. Saturate the foam brush, and start spreading it on the top and side edges first, switching to the front face of the wood when you’re done. Allow the epoxy to dry then seal the bottom edge and the back of the plywood. This type of sealant, as its name indicates, works itself deep into the plywood and dries transparent. It also requires less maintenance than other kinds of epoxy sealer. You can use another marine-grade sealer if you like but you will need more coats and will have to reapply it every three or four years.

Add Subsequent Coats
It’s a fact that plywood will rot regardless of what kind it is, but if marine plywood is not properly sealed with the right number of coats (especially if being used as a hull) it will deteriorate unexpectedly and cause serious problems for you. With normal plywood, you would use two coats of sealer, maybe even three. A good rule of thumb for sealing marine plywood is to apply as many layers of sealer as there are layers in the plywood. If you have purchased plywood with six layers, for example, apply six layers of epoxy to seal it. Between each coat, you add, gently sand to rough up the surface for better adherence of the next coat. Make sure you also use a tack cloth to remove dust before continuing to brush on more epoxy for best results.

*** Also if you are not careful when cutting ply you can damage the edges ****

Correx This is from one supplier. They only sell in 5 or 10 sheets

2.4M x 1.2M

Available Sheets Types and Thicknesses
Thickness Colour Fire Retardent
2mm Black No
2mm Translucent Yes
2mm Translucent No
2mm White Yes
3mm Black No
3mm Translucent Yes
3mm Translucent No
3mm White Yes
4mm Black No
4mm Translucent Yes
4mm Translucent No
4mm White Yes
6mm Translucent No
6mm White Yes

One thing to note is that you could buy Correx which is not flame retardent. Is that something to be concerned about ??
A 6mm Correx board is £19 delivered rolled or £26 delivered flat on eBay.

Rubber sheeting

Fred did you mean Insertion Rubber Sheeting. This is heavy duty sheeting used in horse boxes etc. Probably £40 for a sheet.

I’m going to make my template in 6mm external ply. £20 a sheet, enough to do 2 (my wood work is bad) then make a decision. I do like the Correx solution.

One use for Correx is under vinyl flooring. One grandson does this and has delivered 2 thin sheets free of charge. I’m thinking maybe bond them each side of a plywood shelf ??

Onwards and upwards

Tom

• This reply was modified 4 years, 1 month ago by Tresjolie.

[Tresjolie]

Thanks Tony. I completely misunderstood your post. Where did you source the corex and mat and what are their dimensions. I understand the need for the seal and have a lot of mastic on order. We won’t be using the van for a while so I’m going to reseal the screen before I replace the shelf. The ply I’m buying is very cheap so I’m going to make a template with it to use for modelling the final shelf. The problem at the moment is self-isolation so i can’t wander around looking for stuff. Sorry for the misunderstanding. If the corex is your permanent solution I’m happy to use it. The thought of removing ply in future fills me with dread. Thanks in advance. Tom

[Tresjolie]

Hi Fred and Barry

I’ve ordered the same materials used by Pam and Bill. It’s not the best time to experiment as sourcing the materials is difficult. I like the temporary nature of Tony’s shelf as, like him, I’m not confident I can seal the windscreen. So far the stuff I’ve ordered is about £100 with delivery. The original lasted 14 years without special treatment. At 78 I think I can live with that. The difference between hardwood ply and marine ply is subtle so I’m using hardwood ply to model the shelf before I make a final decision. It would be nice not to have to use ply. If you can think of any alternative material with strength and soundproofing let me know.

Removing a ‘glued on’ plywood shelf is not easy if it is not totally rotten. You have to chip away at it with a chisel and hammer.

The ply has to be rigidly fixed to the ABS and underneath/abutting the window seal using mastic.

I do wonder if replacing the window seal with the shelf in situ could make it difficult to get a proper seal.

Tom

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