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#1 25 May 2020 2:13 pm

Robert Cooper
Member
Registered: 10 May 2020
Posts: 3

Epoxied bolts in Eastwood Pram bulkheads not straight.

I have set the bolts in the bulkhead and epoxied them in place. Unfortunately they are are not perpendicular to the bulkhead so the opposing bulkhead wont fit!


I did wonder if I heated them the epoxy might make the epoxy pliable enough to straighten the bolts. If this did work would the strength of the epoxy be affected when the assembly cooled or should I just heat the bolts to remove them and then re-glue them?

Many thanks

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#2 26 May 2020 1:29 pm

spclark
Member
From: "Driftless" Wisconsin USA
Registered: 19 Mar 2020
Posts: 465

Re: Epoxied bolts in Eastwood Pram bulkheads not straight.

How far ‘out of square’ are your bolts?

And as I’m not familiar with how an Eastport Pram gets the corresponding holes sealed on the mating bulkhead, I have to wonder if just opening up those holes a bit (if that’s all that’s needed to make them accept the glued-in bolts) with a rat tail file might be a practical solution?

Heating epoxy certainly allows things to be removed that have been bonded with it but I hesitate recommending this if you want to be confident the epoxy will still grip those fasteners enough once it’s cooled. If you have the capability to do this at all I’d pull ‘em entirely then re-glue using alignment blocks that have been drilled on a drill press to ensure the bolts get glued on perpendicular.

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#3 26 May 2020 6:44 pm

Robert Cooper
Member
Registered: 10 May 2020
Posts: 3

Re: Epoxied bolts in Eastwood Pram bulkheads not straight.

Thank you.

This is the nested pram which separates between the two bulkheads. There are 6 bolts  which are epoxied into Bulkhead A which hold it together To bulkhead B.  The bolts are 60mm long and about 8mm diameter. Both bulkheads have been drilled filled with epoxy and then redrilled. The tolerances are quite small and it was drilled without a drill stand. The screws are only slightly out of alignment.

What I have done is to warm the bolts sequentially with a solder iron just enough to allow the ones that wont go to be fitted into the holes. They have now all to have gone in. I hope that when they cool they will be correctly positioned. If there is any sign they are not absolutely secure I will remove them and redrill as suggested. Using a drill stand and alignment blocks seems a good idea- maybe it should be in the instruction from CLC?

From what I can find on the net there is a glass transition temperature  or Tg above which the polymer molecules become more pliable but don’t degrade until higher temperatures are reached.

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#4 27 May 2020 12:51 pm

spclark
Member
From: "Driftless" Wisconsin USA
Registered: 19 Mar 2020
Posts: 465

Re: Epoxied bolts in Eastwood Pram bulkheads not straight.

Sounds like you’ve found a workable solution. That bit about Tg is good to know; the only time I’ve needed to heat epoxy was when pulling stitches! That operation was easy when I got stitch wires hot enough to set the epoxy holding them to smoking! Once that’d started they slipped out quite easily but the epoxy surrounding them’d turned whitish & kind of granular.

For your Eastport pram that epoxy’s not so much valued for structural integrity as for maintaining the bolts’ alignment so I doubt what you’ve accomplished has affected that character much at all. If once cooled they’re held firmly in their new position they should remain that way, they’re loaded only when the two hull halves are ‘married up’ with washers & nuts to bring both sections into firm contact.

After your first few forays on the water I’d check to make certain all six bolts are still secure in their mountings once you’ve separated the halves. I doubt you’ll find anything worrisome but it’s good to know if one or more are loose before it leads to a problem.

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