How to fix a busted transom?

[Bubblegoose]

We had some bad weather here last night, and unbeknown to me, a few tree branches had made their way into my local boating spot.

I just got a new prop on the boat, and was testing it out (HK Genesis, put on a slightly more suitable prop the x440). And was having a nice hoon. Very impressed by the prop, it fixed all my issues I had with the boat with slow take up, and sub par performance. It bloody flew.

Sadly, as I was chucking it full throttle, I saw the boat nose dive and flip several times before coming to rest (thankfully right side up). I had to drive in forwards as the drive line was slipping, the crash must have knocked it around a bit. But I managed to bring it in using reverse (which is usually locked off, but I trimmed it in).

When I got the boat back to shore, the whole strut was messed up and the rudder was knocked right back (thankfully the nylon screw broke as I fear the damage could have been a lot worse)

I have included some pictures of the damage it sustained, Probibly not too major in the scheme of what could have been, but in urgent need of attention none the less. I have removed the hardware, and stripped back the paint where the hardware attaches and around the cracks.


Image 1
Image 2
Image 3

(note the line that goes through the bottom holes is a pencil mark, most likely drawn when the hull was made by some Chinese kid)


Fibreglass and boats are a new thing to me, much different to what I am used to working with when it comes to RC.
What would be the best way to fix it?

[Diegoboy]

how thick is the transom doubler? from the images, it appears that the doubler is split. can you post a pick from the inside?

[srislash]

Here's what I did http://forums.offshoreelectrics.com/...19-Transom-fix

[Diegoboy]

Make sure to pull out the cracked doubler (if it is cracked) and replace it with thicker ply

[liteumup69]

Fiberall..... its a product made by UPOL, you can find it online, a good automotive store, or auto paint supplier, It's crushed glass in a fiber resin, stronger than fiberglass, water proof, and available in regular or fiberall lite. the lite is smoother and spreads easy. you mix it with a hardener kinda like bondo, I have used it on real boats and rc boats.. zero issues..

http://www.tcpglobal.com/autobodydepot/upol-preparation.aspx#ASGFF

[Bubblegoose]

Thanks for all the responses guys.

I will try and get a photo of the inside when I get home. However it might be difficult to see anything. I had trouble enough actually getting to the bolts to get the transom off in the first place. the servo/receiver tray, and strengthening rails dont allow much space for tools. In the end I had to modify a piece of round steel rod with an angle grinder, into a square end to take my socket wrench bit. But even then, it was tough as the screws are seated so low down, there isn't really room for the socket head to encase the bolt, I was just kinda holding one side of the bolt on an angle. I'm thinking I might be better flipping the bolts around, and having the buts on the outside and the screw head inside in future.

From all the info given, I have formulated a way to do it, let me know if it will work ok or not (note, i'm not going for breakneck speeds here, so increasing strength isn't important, It just needs to be as strong as before)

• Try and removed the cracked doubler (i assume this is just a small piece of ply on the inside of the hull that is used to strengthen the transom?). I don't think this will be easy, as I cant even get my hand anywhere near the inner side of the transom.
• Cut a piece of ply the correct size to replace the old doubler.
• If I can remove the doubler, epoxy in place. If not, epoxy over existing doubler.
• fiberglass over and around the edges of the doubler (might do that as the same time as the step above)
• sand down the cracked area on the outer side of the transom, and under the back of the hull where the cracks in the gelcoat are prominent and remove gelcoat.
• Replace gelcoat with epoxy resin (I don't want to fork out on a tub of gelcoat when I believe epoxy should do a good enough job), slap a bit extra on the transom.
• Sand down cured epoxy from the back of the transom, get it nice and flat at the back, and smooth on the bottom.
• Slow drill the holes out with a sharp drill bit.
• Buy some new stainless bolts, and washers to make up for the extra girth on the inside of the hull (if I can't remove the doubler).

In my head it seems like it will work. Should I do anything differently?

Thanks for all your advice guys!

[Bubblegoose]

Here's what I did http://forums.offshoreelectrics.com/...19-Transom-fix

Srislash, may I ask what the reason is to modify the pads on the miss geico? Does it just make it a bit faster in a straight line and less twitchy?

[srislash]

Some if not all of the pads can have a concave or cup to the ride surface which may push the nose down or up depending.Add to that only one side may do it,ya get it.No point in having something fighting against you when you are setting it up.
Oh,and your problem getting at the bolts and doubler is why I stuck a threaded piece of aluminum in there.
Here's a little bit of mine http://www.youtube.com/watch?v=tzzKR...dN7QA74CTk-ubw

[Bubblegoose]

Yeh It would make it much easier. I might actually use aluminium rather than ply, as I think it would make it a fair bit stronger and less prone to cracking. However I don't think I would tap it out like you did, Just reversing the bolts should be fine for me, and get replacements with a Phillips head.

With the genesis hull, as you can see in image 3, it has rails down the length of each pad. ( I think they are called chines?)

[srislash]

You mean the steps down the length of the sponsons?

[Bubblegoose]

If you look here, you can see the rails I am talking about that run the length of the hull (well, the length of each pad)

[srislash]

Yes I see them .Do you question them?
It has always been my theory that they are there to aid in getting the hull on plane and maintaining plane.

[Bubblegoose]

I'm just saying I don't think sanding them down would help the boat out much. It tends to lerch to one side that's all.

[srislash]

Your ride pads are tapered up,on the Geico they are flat so it does make a difference.Mono's can have it too.It's just the care taken in the mould and curing and such.It probably isn't relevent unless you go and get seriously addicted to speed.
What do you mean lurch to one side?

[Bubblegoose]

Just like when it's getting up on plane, it tends to lean/roll to one side, about 30 degrees Id say. once it's going flat out it tends to level out. The weight of the boat seems to be fairly centred, the batteries sit in each hull the exact same distance appart, the motor is dead centre, ESC and servo/receiver is too.