Spider Crack Repair Tool

[wooster]

Hi all,

 

I have a number of unsightly spider cracks and also some larger ones caused by historic bumping/aging/weather ( before my ownership, obviously :-) ! ) and I'm going to spend some time repairing these over the next few weeks. I believe I need to dremel them out a little then clean and fill with gelcoat. I need to buy a dremel and I'm looking at the budget end of the market. What sort of power do I need and do you have any recommendations as to makes and models?

I'm wondering if something like this might be powerful enough do the job? I don't anticipate using it a lot after the cracks are sorted so I'm assuming a lightweight low-powered one would be fine?

Thank you

[wooster]

or maybe this?

[Vaughan]

2 hours ago, wooster said:

or maybe this?

Either of those will do well.  You don't need anything fancy - I bought mine from ALDI about 10 years ago, for €16.

I use the long thin sandstone bit, shaped a bit like a cucumber, and drill a groove about 2mm wide.  Try to obtain a bevelled edge, rather than a square edge.

The difficulty might be in matching the colour of the gelcoat.  They say there are more than 20 different shades of white!

[wooster]

Thanks. I thought for what I was doing I didn't need anything heavy duty but thought I should make sure! 

Good advice re technique too.

I do have some gelcoat left over from a professional repair a year or two ago and they kindly left me the stuff they didn't use. It matches pretty well.

[Karizma]

I'd be interested in seeing how this goes if you take some before and after photos.......and share your experience.

Mine also has some and I'd like to get it off the 'to-do' list at some point in the next 5 years 

[Regulo]

As it was explained to me, years ago, spider cracks are a symptom of underlying stresses in most cases, and will gradually return if the root cause is not dealt with. Not sure whether that's entirely true, but worth a try at a repair. Nothing lost by trying.

[JanetAnne]

Some cracks are due to stresses especially as boats age and lose their strength.

Then there are the fractures caused by movement in the superstructure from removing bulkheads... open plan living it's called.

Don't forget impact damage. That'll account for cracks around the extremities.

Fractures around deck furniture caused by a bit of flex either in the deck itself  or through a lack of decent hardwood or plywood pad underneath.

And finally there's just plain movement. You'd be amazed at just how much flex there is in a 40ft broads cruiser on a rough Breydon crossing!

If you can work out why the cracks are there before you repair them you may stand a chance of them not returning.

[wooster]

Alrighty. I just got back from holiday and then up to the boat for a few days so here's a couple of pictures of  err.. my cracks, so you know what I'm talking about. I'm pretty sure they major ones are collision damage, would you agree? If so could I just fill them in with gelcoat after drilling a bit and expect reasonable success?

[Vaughan]

These "spider cracks" are quite clearly collision damage.

In the second photo a "repair" has been attempted previously but without success.

I think you need to see a boatyard about this.

[NeilB]

That's not a 5 minute job, the rubber strip will need removing as well.  You may also find the damage is deeper than just gel coat, you'd be surprised how deep the damage can go when you start rummaging around.

[BrundallNavy]

The larger damage needs to be ground right back then a couple of patches of glass fibre mat then gel coat over and sand back and polish. As has been said it’s not a quick job but it is achievable with a bit of time and effort. 

[wooster]

Yes I realise these ones are larger than most. (I have spider cracks too.) Hmmm. 

Well looks like a Boatyard job then. 

[wooster]

On 28/06/2024 at 09:44, Vaughan said:

These "spider cracks" are quite clearly collision damage.

In the second photo a "repair" has been attempted previously but without success.

I think you need to see a boatyard about this.

HI,

I've contacted 2 boatyards and one independent repairer without success. They've looked at it then, despite a few attempts by me to contact them they go quiet. I don't know if they reckon it's too small a job or what?

Whatever it is, it's looking like I'm either going to have to leave it or give it a go myself. I've been researching this repair thing and, although it is more work than I originally thought, I'm gearing up for it unless it's likely to be beyond my novice capabilities? Is it really harder than a DIY job?

I'm tempted to go for the method described by @BrundallNavy

[MargeandParge]

When  I look at the first photo it looks like it has been painted to me I am not a professional but that does make the repair easier in my opinion. Check to see if you are looking at paint or gel coat.

Kindest Regards  Marge and Parge 

[wooster]

11 minutes ago, MargeandParge said:

When  I look at the first photo it looks like it has been painted to me I am not a professional but that does make the repair easier in my opinion. Check to see if you are looking at paint or gel coat.

Kindest Regards  Marge and Parge 

Yes there's been a botch job done. They've just bunged some filler in, in a slapdash way, and then they've put some paint over a the section ( about 4 or 5 ft in length) to try and disguise what they've done, I guess. It isn't the same colour of the rest, which does seem to be gel coat.

I remember someone telling me that if you buy a hire boat, it will have been used a lot but well looked after. Definitely not the case with mine, I'm afraid. I've spent a fortune trying to rectify the atrocious cover up jobs they've done. Really shockig to me. It's been a learning experience all right ! 

[ExSurveyor]

It might be worth trying Brooms or Bridgecraft.

[Smoggy]

Have a chat with the guys at sheerline (thorpe st.andrews),  they did some repairs on mine some of which needed old epoxy filler taking out first and matched the colour great, mine is an off white princess.