Fiberglassing over ABS

[Prins Willem]

This question came in on the WSBA website. I offered to post it here hoping the discussion will be informational to all. The question's author is from Canberra Australia.

Hello!
What a pleasure it was to come across your website!!! I have been trying to
find an answer to the question of fibreglassing over abs plastic, and nearly
fell off the chair when I came across a reference to the Kyoshu Fairwind model, for it is for this exact model that I am seeking some information!
My son and I were given an elderly part completed model of the Fairwind,
which has a yellowing abs plastic hull. Its condition is such that to
proceed with it as it is would be foolhardy, and so I suggested top him that
we cover the hull in fibreglass to strengthen it. I have been unable to find
any definitive information on the compatibility of fibreglass over abs
plastic until I came across your site which refers to the joint use of these
two building materials.
Can you please advise us on whether such a process can be undertaken with
any chance of success, or are we likely to land up with a large dissolved
plastic puddle at our feet? We have resurrected a very old wooden Billings
model (of the Italian motor cruiser Neptune) that we were given using this
technique, with good results. However, I am not sure of being able to do it
with the abs, so seek your words of maritime modelling experience!
Any help that you may be able to provide will be most welcomed.
Cheerio for now!

I gave him my e-mail address to contact me directly instead of through the website and he sent me this follow up (with another question).

Hello Bill!
Thanks for your time and trouble in answering my query. I would like to take
you up on your kind offer of posting my query on your model boat forum which
you mentioned - there must be someone out there who knows the answer to my query! Its really quite odd really - I thought that my question would have
been something experienced by many a maritime modeller in the past, with a
definitive answer not too hard to find. I also made an error in the vessel
involved - I had "Fairwind" in my mind when I initially contacted you, after
reading about it on the net. Our marine antique is in fact the Kyosho
"Sydney", Kit No. 1652, a single channel model. (Our son however has worked
out a way in which to add the second channel to control the sails using an
extended arm on a conventional servo, but I think that the servo might not
be robust enough for this task). I can find absolutely no reference to this
model anywhere on the net, not even under the Kyoshu website, so I think it
really must be quite an old model. Have any of your members heard about it?
Again my thanks to you for your time and trouble in replying to James and
myself, and for your kind offer of assistance. Happy sailing!
Cheerio for now!

Who has experience with glassing over ABS? Is anybody familiar with the Kyosho Sydney?

[steveciambrone]

Unless the plastic is brittle, I would not put glass on it. it would just make it heavier. A simple paint job might be the thing to do. If it is extremily brittle then it may be a write off anyway.

Steve

[der kapitan]

Laying fiberglass over an old ABS hull will, at best make for a heavier hull as Steve has said. ;)

Also, I would have doubts as to whether there would be good adhesion to the plastic---. :eek:

[Brooks]

If he is simply needing to strengthen a brittle plastic hull, then any matrix plus any compatable glue would do the job. Matrix could be glass fabric, polyester fabric, brown construction paper, etc. Glue for saturating and adhereing the matrix could be.... whatever you ABS guys use when making a model. I made an ABS hull model (Krick Patricia), but it was so long ago I can't remember what adhesive I used.

Worst case scenario, use the old hull as a plug to make a new fiberglass+epoxy resin replacement?

[towboatjoe]

I would suggest using epoxy finishing resin with 3/4 oz mat. It won't damage the ABS and is lightweight compared to polyester fiberglass.

[toesup]

I think you will find that ABS is a law unto itself. Very little will stick to it and it needs specialist glues to get anything to 'bond'.
If you attempt to put GF over it, sooner or later the two layers will seperate..

I seem to remember something called 'Stablit Express' being used on ABS...

[Aerominded]

I think you will find that ABS is a law unto itself.

You are right on, Toes! regular epoxy will peel right off of ABS... I have recently had great luck with West Systems G-flex on ABS as an alternative to Stablit Express... G flex is a little too thick to try to glass with though...

[Tugboat Andy]

You are right on, Toes! regular epoxy will peel right off of ABS... I have recently had great luck with West Systems G-flex on ABS as an alternative to Stablit Express... G flex is a little too thick to try to glass with though...

LOL - My dad has been on me to try some G-flex...and I held up my nose to it.... :o

Guess its time for a slice of humble pie... :D

[toesup]

Patmats 2005 experiences with ABS... :)

http://www.rcgroups.com/forums/showthread.php?t=434843

[pompebled]

My experience with reinforcing ABS with glasscloth and epoxy is limited to powerboats, where the weight of the batteries and motormount/motor tend to pound holes in the ABS...

I sand the ABS really rough, so the 'fibres' stick up, put the thin glasscloth in position and tap it onto the ABS using Aceton or MEK.
These solvents are very agressive towards ABS so, whatever you do, DON'T soak it, your ABS will deform.

Tapping the glass with as little solvent as possible will work the glasscloth into the ABS.
Once the solvent has evaporated completely(!), the glasscloth is fixed onto the ABS and provides a basis for another layer of glasscloth and epoxy.

My guess is that one layer onto the ABS followed by one layer + epoxy should strengthen the hull sufficiently, without adding too much extra weight.

Access to the interior is going to be an issue, unless you can remove the deck completely, preferably without destroying the hull...

Regards, Jan.

[cdog46]

Using regular resin on ABS is not a good idea-the resin may eat the ABS. Epoxy resin is OK.

[green-boat]

ABS- Acrylonitrile Butadiene Styrene

Polyester resin will dissolve styrene where Epoxy resin won't. Since ABS is so slick you will have to do some major roughing up of the surface to get the Epoxy to hold.

[Aerominded]

LOL - My dad has been on me to try some G-flex...

G-Flex is awesome! Your dad is right! You have to try it! :)

[Prins Willem]

Guys,

Here is the response from "down under". Take a bow.


A Good evening to you Bill! (Antipodean time...)
WOW!!!!! I am most grateful to you for posting our query onto your forum,
and to your members for their responses. I am amazed at the depth of
members' knowledge available and the willingness to share it amongst
similarly-minded folk! (This is the first time that I have ever used a
forum). I am indebted to you for your kindness towards our son James and
myself, and wish to put out there to your members our appreciation to you
Bill for your kindness in posting our query, and to all the respondents who
have so generously given of their time and knowledge to assist us to solve
our problem. It makes you realise that there are a lot of nice and
knowledgeable folk out there! A Thankyou to you all.
Based on the advice received we will proceed, and look forward to advising
you of the outcome in due course. Our maritime antique is more of a project
in restoration rather than the production of a fast racing yacht, but we
note the comments about the extra weight. I think our goal will be to get it
watertight and shipshape for sailing for fun rather than tuned for racing at
this stage. (I might be a bit niave, but I think there are a lot worse
things for a 15 yo boy to be involved with than model boats!) I think that
this may also mean I need to learn about forums too!!!!!
Again, my thanks to you Bill and to all the others for their assistance and
advice.
Cheerio for now!
Bill and James Atkinson. Canberra, Australia.

[Aerominded]

By "proceeding", does that mean he plans to glass over ABS? what method did he choose? would be interesting to know the result, long term...

[Prins Willem]

I have suggested he read some of the threads on the forum to get comfortable and when ready join in. I also asked that if he has a digital camera he take and send pics. I'll e-mail him about the course he has chosen with his model.

[Shaun Hendricks]

Um, just a thought, why not use the ABS hull to make a negative mold from and do a new fiberglass hull from it?

I mean, you could use gelcoat and a nice light cloth = new hull for a beloved boat.

[Barnacle Bill]

Hi Shaun!
Thanks for the suggestion - a couple of others suggested along similar lines. The boat has a lead weight already moulded into the keel, making using the hull as a removable plug impossible. My current thought is to roughen the surface and use epoxy as per the suggestions from the oracles that inhabit this discussion forum. I will let you know how it goes when it happens, which shouldn't be too far away.
Cheerio for now! Barnacle Bill

[pompebled]

As the lead filled keel of the Fairwind was mentioned, I thought I'd throw in another suggestion: A keelbox.

http://www.modelzeilen.nl/forum/viewtopic.php?t=127&highlight=fairwind

Only do this when you're not going to enter your Fairwind in competition, as this will make it illegal, next to much quicker.

A number of sailors I know have performed this surgery on their bulky keels of the Fairwind , the Robbe Scandia and the Robbe Comtesse.
Main reason is reducing the drag of these outdated designs.

While you're at it, you can realize Shaun's suggestion in the process; cut off the keel, close and fair the hull, make a mold of it and incorporate a keelbox the epoxy hull you'll pull from that mold.
Having a keelbox allows you to use different keels for various wind conditions aswell as adapting the draught to the waters you sail in.

The keel in the pics in the link is the Graupner Saphir keel, which is available as a spare part.

Regards, Jan.

[Aerominded]

Welcome to the forum, Barnacle Bill! :)

[Prins Willem]

Barnacle Bill,

Glad to see you joined in. A great bunch of guys on here (oops, Girls too, Sorry Umi & Capt Sunshine). Be careful though. This model boating stuff can be addictive. You look around this site at all and your imagination will run amok.