LB26

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les2021
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Re: LB26

Post by les2021 »

Thanks

Jacques / Dan / Fuzz

I have nearly completed the stringers, once I have these rapped up I will measure the engine again and try and get it as accurate as I can. I will then check it against my mock up.

Jacques I will do a quick drawing and ask you if thats ok to add some measurements regarding the position of the shat log. I can then check and try and find out where the problem is.

The stuffing box recommended by the engine supplier is the one attached.

Les
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Fuzz
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Re: LB26

Post by Fuzz »

That seal will be about a foot long. I am sure the data sheet will tell you how long it will be. You also need to know the id of the rubber bellows. You might have to adjust the od of your shaft log to get a good fit.

les2021
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Re: LB26

Post by les2021 »

Afternoon All

Jacques some info for when you get back on dry land.

Today I decided to go through the whole set up for the shaft log again.... when I pull the line through the log it does show that I got it wrong somewhere which is really frustrating as I checked and checked again when setting it up. The line is parallel through the tube showing the angle is right ! the only problem is it is about 5mm from the inside top of tube which backs up my earlier posts that I have slipped about a 100mm forward.
To re core drill a new tube would be a pain as it is so close to the existing tube. Your thoughts please....

I also re measured the engine and made the mock up to match the bottom of the transmission and the sump. I clamped a couple of timbers to the stringers taking the place of the angle steels. The timbers are at 8 degrees which I think if I have read it right is good and correct, if I cut the shaft log back to the line marked it would give me 100mm from the stuffing box which is 225mm to the transmission this the supplier says is OK !!!

In this position I get around 900mm to the cabin door, frame D. which I am fine with ( but then I am easily pleased :lol: )

Anyway let me know what you think and how I should proceed.

Cheers

Les
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fallguy1000
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Re: LB26

Post by fallguy1000 »

I am not going to recommend. I can tell you how I'd go about the remodel.

There is no reason to make life impossible, the foam core is easily repaired. Use an oscillating tool with a carbide head and start on the inside. Cut out the entire section in the vertical plane. Do not attempt to cut it out on an angle. From the inside, cut each side and from the outside each side and finish the cuts on the ends from the accessible sides. Done right; you'd have a square piece of perhaps 2-3" wide by 12-18" long. It should take 30 minutes to an hour.

Taking the removed piece out and cleaning it up another hour.

Remove enough material around the hole by taper grinding to do a 2" overlap of all glass and all cores. For the skeg, same, cut it back to allow some overlaps. If it is a stack; remove 2" each way of the outer core and leave some room for putty.

In one day, you should be able to remove and replace the hull cores and hull laminates. The second day; the skeg repair. Using some screws and a helper; temp screw or perm screw the new skeg parts in place with epoxy putties. If you dry prep a radius, you would be able to apply laminates the same day. A bit tricky from the bottom side. I usually hot tack the repair by letting neat coat of epoxy go a bit past the kick time, then the next piece of glass sticks real well.

About two-three days gets you close to back to pre-hole..
My boat build is here -------->

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jacquesmm
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Re: LB26

Post by jacquesmm »

Did you cut the stern tube? Is there enough room to slide the shaft seal over it and use minimum two hose clamps? What is the distance between the end of the tube and the coupling? You need at least 15 cm depending on the model, maybe 30 as Fuzz wrote. It's the compressed length than matters. You must be able to slide it on and off.
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les2021
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Re: LB26

Post by les2021 »

Hi Jacques

The tube is not cut yet. The seal I am planning to use is the one on my posts about 5-6 back it is about 209mm long compressed and the clamps look as they only go over the log by about 30-40mm to secure the clamps. In it's current position I can get around 130mm from seal to coupling, as mentioned the engine supplier says this is enough ( but he would !!! ) In this position I have about 850mm to frame D.

As I mentioned in my last post I have reset the jig up to check the position of the shaft log, it is much easier and more accurate with the hull the right way up. My string line is parallel but 5mm from the inside top of the log showing it needs to go aft, but even if this did go back 100mm I am not sure it is far enough to match the drawings !!!

The main thing is though to make the current situation work without effecting the boat OR move the shaft log :(

The other problem is there are no other threads of LB26 builders to discuss with.

Questions

My engine stringers are spaced further apart to accommodate the engine, so if I then leave 300mm to the outer stringers it means that between frames C and D my stringer height if I keep them 12mm below DWL are only about 60-70mm . Is this ok or can I raise them up above the DWL to get more depth if needed.

Transom Knees

I am going to fit two knees to leave the centre clear for the rudder. My plan is to fit them on the inside of the engine stringers and tab them to the transom and stringers. Is this ok

On the laminating schedule do the knees come under superstructure or stringers and floor frames.

Sorry to be a pain Jacques, I just can not see where the error is, I have measured time and time again.

So work your magic ( please )

Cheers

Les

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Re: LB26

Post by jacquesmm »

les2021 wrote: Tue Apr 12, 2022 11:13 am
As I mentioned in my last post I have reset the jig up to check the position of the shaft log, it is much easier and more accurate with the hull the right way up. My string line is parallel but 5mm from the inside top of the log showing it needs to go aft, but even if this did go back 100mm I am not sure it is far enough to match the drawings !!!

The main thing is though to make the current situation work without effecting the boat OR move the shaft log :(
Let's separate the perceived problems. See above: what is the problem with that? You have a shaft axis and the engine location. What is it that does not work?
It sounds fine to me as long as the engine and mounts do not hit the hull.
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jacquesmm
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Re: LB26

Post by jacquesmm »

les2021 wrote: Tue Apr 12, 2022 11:13 am Questions

My engine stringers are spaced further apart to accommodate the engine, so if I then leave 300mm to the outer stringers it means that between frames C and D my stringer height if I keep them 12mm below DWL are only about 60-70mm . Is this ok or can I raise them up above the DWL to get more depth if needed.
The stringers height is set by the engine mounts, you don't have a choice. The width is set by the mounts also but on a L bracket bolted through those stringers. From the engine drawing, I see enough clearance between the mounts, nothing sticks out.
Can you post the engine drawing as a downloadable file?
Sorry but I do not see where the problem is, it looks fine to me.
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jacquesmm
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Re: LB26

Post by jacquesmm »

les2021 wrote: Tue Apr 12, 2022 11:13 am
Transom Knees

I am going to fit two knees to leave the centre clear for the rudder. My plan is to fit them on the inside of the engine stringers and tab them to the transom and stringers. Is this ok
OK, that is expected.
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jacquesmm
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Re: LB26

Post by jacquesmm »

les2021 wrote: Tue Apr 12, 2022 11:13 am
Sorry to be a pain Jacques, I just can not see where the error is, I have measured time and time again.
Sorry but what is the problem we are discussing?
At first, I though it was insufficient clearance either the oil pan or the bell housing but now that I see the new or corrected template, it looks OK.
What is it that does not fit?
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