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[Howard]

Hi, All my fellow mayhemers,
I have a vac formed hull but which I have used because I thought it was faulty IE, a little thin in places and odd marks which I would,nt be happy to try and sand out as it would then make the hull even thinner, did ask some club members if I could brush on so resin to make thicker but was told no as the resin gets warm and could deform the thin plastic hull which I understand,so try-ed thinking out of the box, so I have brought some sticky banage you know the sort white or blue  that sticks to its self, and wondered if I lined the inside with this sticking it to the hull and with it being soft and breathable could I then spread some resin on that soak into it but without the heat getting to the plastic to much or would I just look very foolish, thank you if you have stuck with it and read this far.
                                 Regards Howard.

[Shipmate60]

Howard.
The resin will not bond to the plastic it tends to sit on top unless the surface is well roughed.
It might be better to add a layer of plastic card inside the hull but use the cement sparingly as it can deform the plastic.
Using something like a thin coat of P38 then adding the interior plastic might be a better solution.

Bob

[Howard]

Hi bob,
 thats why I was wondering if the white or blue sticky bandage stuck to the inside of the hull then soak this with the resin work as its breathable so hope slightly porus and would soak into the cloth plus some of the heat.
                   Regards Howard.

[DickyD]

Resin wont stick to plastic as Bob said, so it wont work.   

[Stavros]

Only one place for this sorry to say it BUT bin it everyone is telling you the  same so am I

IT WONT WORK.

The only thing that would POSS work is to build the thickness of the hull up with plastic card BUT the MAIN problem is simple really you cant get the glue to fully impregnate the card it would only do the edges of the patch



Dave

[Guy Bagley]

there are different resins, - speaking from someone who works alot in plastic- there are resins which will stick to plastics and dont create alot of heat in the curing process- so you could in effect add resin to the hull, - the big question is are you prepared to spend money on doing it....cheap polyester  resins will no doubt affect the plastic , create a thixotropic curing process and risk your hull, which leaves polyurethane or epoxy based resins- you will need to prepare and degrease surfaces to get a good bond but it is possible- i have strengthened ABS vacuum formed hulls in the past, kyosho hulls, one from Sarik vac form and also a very thin cheap vacuum formed tug hull, so it can be done if the right preparation is done and the correct resin is used....

often electronic potting compound resins can be used too

plasticard  reinforcement could be the option but if the hull is very thin any amount of solvent applied could risk melting the thin hull layer beneath it- once the solvent has evapourated  the bond is usually very strong, its a chemical weld....
to avoid an edge only bond select a  plasticard panel to add for strengthening, dip the face to be bonded into a shallow bath of plasweld allow a 15 seconds or so for the surface to soften and the excess solvent to evapourate then apply... again correct surface preparation will be needed and any contaminents removed ( grease from fingers ect )

plasweld will bond acrylics and most  plastics, try with scrap off cuts first....- this is the cost effective option as quality resins can cost tens of pounds per litre- and vacuum formed hulls are generally very cheap , is it cost effective ??? 

[Howard]

Thank you guys looks like am on a no brainer, just thought if i stuck the sticky side of the bandage to the inside of the hull as its very sticky as if you have ever hurt your leg or arm and the hospital have used it on you you,ll know how hard it is to pull off them once the hull was coverd in it spread the resin over the bandage so it impregnated it and once it setand gone hard I would have a stonger thicker hull, but thank you all for your replys am a little wiser and my plastic bin will be a little fuller.
                     regards Howard.
             

[Neil]

Can you actually see holes in the plastic of the hull when you hold it up to a light bulb, or has the hull gone brittle with age.
if you can answer no to both of these questions, then the hull would be ok to use if cross beams and edging strip is run around the gunwales of the hull.......they don't have to be thgick skins to be watertight......just so long as they don't let water in, and you'll be suprised how stif and strong the hull will become with a few cross strengtheners..........give it a try......you won't waste much plastic doing it, and it'll give you some experience at least.
I'm never in favour of chucking something away unless it is a total loss.
neil

[Howard]

Hi Neil,
 No to both of them I just think when it was made it was stretched a little to far and could be a little thin in places like you I did,nt want to throw it away just thought i,ed might of found a way to to thicken and strenthen it  I,ll put it down as having a senior moment this what i love about mayhem theirs lots of great people out there willing to help when your not sure.
                     regards Howard. 

[dodgy geezer]

If you are concerned about excess heat you can float the hull in a cold bath while you do the work. And if you're worried about excess solvent melting the hull you can rest the relevant part on a flat non-absorbent surface while letting it dry to keep it undistorted. So long as you are able to mend the hull, a hole in it need not be the end, of course...