Thru-bolting swim platform brackets
Printed From: CorrectCraftFan.com
Category: Repairs and Maintenance
Forum Name: Boat Maintenance
Forum Discription: Discuss maintenance of your Correct Craft
URL: http://www.CorrectCraftFan.com/forum/forum_posts.asp?TID=40986
Printed Date: November-16-2024 at 6:50am
Topic: Thru-bolting swim platform brackets
Posted By: bb12
Subject: Thru-bolting swim platform brackets
Date Posted: May-01-2017 at 11:55am
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I'm planning on pulling the tank and thru-bolting my swim platform brackets on my 89 Ski. I've read about every thread on the topic so I have a pretty good idea of what to expect. I just have a couple of questions I wanted to get some feedback on before I go at it... 1) What would you recommend for the backing plates? 2) Thoughts on running the bolts through the inside of the transom so that the nut is on the outside, so you could remove the brackets or tighten them later if need be? 3) I have a tube of 3M 4200 on hand - is that good enough or should I go 5200? Any other suggestions or feedback on this job appreciated - thanks |
Replies:
Posted By: trice
Date Posted: May-01-2017 at 1:35pm
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1. I used 3/8" SS fender washers. More than adequate lateral surface area. 2. When I read this idea it sounded good, however, if using a standard SS 3/8" diameter hex head bolt with fender washers as I am, the hex head will have to be held with a wrench to adequately torque the fastener. The same holds true for removal of the brackets thus requiring movement of the tank and defeating the purpose. If a backing plate for each bracket were fabricated, the hex heads tack welded to the plates, and the plate itself fastened to the back of the boat from the inside, your idea would work. Your idea would also work if you permanently installed/glued the hex bolts and washers with 5200 so that a wrench on the inside would not be required to tighten or loosen the fasteners. I'm going to stick with the hex heads on the outside ( like the original lags were) and having to move the tank to get at the through bolts from the inside to tighten and loosen if necessary. 3. 4200 because the permanent 5200 doesn't seem correct for this application unless using it to secure the hex heads to the inside of the boat which could have consequences. |
Posted By: throttle out
Date Posted: May-01-2017 at 1:59pm
| Why not use some SS Tee Nuts?? |
Posted By: SNobsessed
Date Posted: May-01-2017 at 2:45pm
| I have had T nuts spin during untorquing. Was a PIA at that point. Tapped backing plates would be best, glue them on with some 4200 & never have to mess with it again. |
Posted By: storm34
Date Posted: May-01-2017 at 6:33pm
Agreed! I added aluminum plates on the inside of the Promo transom which had fender washers from a PO installation. Fender washers were far from adequate and allowed the transom to flex quite a bit. I'd say go with something larger to spread the weight. |
SNobsessed wrote:Posted By: bb12
Date Posted: May-01-2017 at 6:47pm
| Yeah I definitely want to use backing plates as that will be the strongest. Where did you find your aluminum plates, Chris? I called a metal fab shop- they said they could make me some 1/8" thick stainless plates. Might be an option. |
Posted By: TRBenj
Date Posted: May-01-2017 at 6:47pm
| There should already be (wood) backing plates glassed into the transom for any boat that came with a platform from the factory. Unless they're mush, fender washers on the bolts you can access should be plenty. I'd add some thickened resin to the blind screws/lags that enter below floor level. 4200 for sealant on all the bolts and brackets is fine. |
Posted By: 8122pbrainard
Date Posted: May-01-2017 at 7:11pm
| I'd stay away from fender washers since they are typically thin especially in SS. I've seen them crushed and in fact have done it myself when they are on wood. Yes, I also agree with Tim that the condition of the wood backing in the transom needs consideration. |
Posted By: bb12
Date Posted: May-01-2017 at 7:41pm
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The wood is good - no mush :) The lags still bite fine. I had a leak last summer on one side. I was on vacation at the time so in a pinch I had the local shop/marina fix it. Well, they used silicone and we all know how Pete feels about that...So, I've since dug all of it out and I figured rather than re-install with lags I would reinforce the brackets on the inside and seal it up for good. And I'll note that upon removing the lags I discovered that one of the holes on the port side goes all the way through (this is due to the fact that a PO added removable brackets and the hole locations on the ends were different than the original). |