SC-1 by LEGION 12 - Dumas - 1/35 Scale - Sub Chaser

[LEGION 12]

This is my first wood build I've only built plastic ships before , I have already built the keel and the bulkheads and in the process of planking which is where I started having  problems . 

[LEGION 12]

[LEGION 12]

The planks aren't contacting the 2 rear bulkheads still trying to figure out why . 

[VTHokiEE]

Looks like a very interesting build.

 

Regarding your planking issues, did you fully fair the frames? I can't fully tell from the pictures, but there seems to be a good bit of laser char on the frames which may indicate that you need to fair the bulkheads more to get a better run for your planks.

[LEGION 12]

2 minutes ago, VTHokiEE said:

Looks like a very interesting build.

 

Regarding your planking issues, did you fully fair the frames? I can't fully tell from the pictures, but there seems to be a good bit of laser char on the frames which may indicate that you need to fair the bulkheads more to get a better run for your planks.

In hindsight I should have but the instructions made no mention of doing so . Also the plans calls for 36 inch planks and I was supplied with 30 inch planks so I had to splice 2 together to get the correct length . 

[VTHokiEE]

Did you glue them with wood glue/PVA? If so I’d recommend using isopropyl alcohol and removing the planks and then fairing the frames. I can point you to a link if needed on fairing.

 

It is frustrating, but you’ll be happier in the long run doing it.

[LEGION 12]

16 minutes ago, VTHokiEE said:

Did you glue them with wood glue/PVA? If so I’d recommend using isopropyl alcohol and removing the planks and then fairing the frames. I can point you to a link if needed on fairing.

 

It is frustrating, but you’ll be happier in the long run doing it.

I used Gorilla wood glue on the edges of the planks and Ca glue to glue the planks to the bulkheads , there are only 4 planks installed 2 on each side . The first plank is attached to the stringers so there is nothing to be faired as far as I know . 

[lmagna]

Interesting build Legion. I have always liked the 110 foot sub chasers.

 

Not only would I also recommend backing up and properly fairing the frames like VTHokiEE said, but I would also get a building board to mount the frame on while planking or sheeting or whatever you want to call it. This vessel has a long narrow hull that is very easy to warp or twist while building and of course you want to avoid that. After you get the entire hull covered you can cut it off of the building board and work with it in the normal way.

[VTHokiEE]

17 minutes ago, LEGION 12 said:

so there is nothing to be faired as far as I know

I suppose it is possible that none of the bulkheads need fairing (especially in the middle of the hull), but I would be a little surprised if the planking runs didn't benefit from some fairing at the bow and stern. You may want to take a look at fairing here: http://modelshipworldforum.com/resources/Framing_and_Planking/plankingprojectbeginners.pdf

 

Maybe it isn't useful, but I feel like the rear bulkhead (at least) will look like the unfaired image below if you leave them as is.

 

[Cathead]

I'll repeat from your earlier question thread, I really think you need to properly bend the planks using soaking and/or heat. Your plank looks like it is bowing away from the bulkhead when it should be sitting tight against it. At a minimum, when you glue them on you should be clamping them so that each plank's surface is fully in contact with the bulkhead. Prebending them makes this much easier as it reduces stress on the glue joint. 

 

In the vertical photo you give above, the plank is properly sitting against the lower (in the photo's orientation) bulkhead. But when it continues up toward the next bulkhead, it maintains its orientation from the lower bulkhead rather than twisting to make proper contact with the next one up (note that the inner edge sits against the bulkhead next to the previous plank, but the outer edge veers away to form a wide gap). That's a problem that is best solved by properly bending the plank. Most hulls require this sort of thing due to their complex 3D geometry. As also mentioned in your last thread, tapering the plank could also help, though the instructions you showed made no mention of this common practice, so I'd suggest trying bending first as this is reversible and repeatable (unlike tapering).

 

It's hard to say this in written words, so if you're not sure what I mean, I can try to come up with a visual example.

[LEGION 12]

9 minutes ago, lmagna said:

Interesting build Legion. I have always liked the 110 foot sub chasers.

 

Not only would I also recommend backing up and properly fairing the frames like VTHokiEE said, but I would also get a building board to mount the frame on while planking or sheeting or whatever you want to call it. This vessel has a long narrow hull that is very easy to warp or twist while building and of course you want to avoid that. After you get the entire hull covered you can cut it off of the building board and work with it in the normal way.

I really appreciate you all trying to help me out , really should started a build log here before I even started . I had it glued  on a building board but the instructions specified I remove it before planking as you can see . Can always glue it back on I suppose . 

[lmagna]

19 minutes ago, LEGION 12 said:

Can always glue it back on I suppose . 

It's up to you really. It can be done either way, but after building a number of long narrow hulls over the years, (For RC use) I prefer to keep them attached to the building board for as long as possible. It is disappointing to go through the building of a hull for a destroyer or gunboat, or in this case a sub chaser and find the hull has taken the shape of a pretzel or banana. For some reason it does not seem to be as big an issue with wide beam shorter vessels like fishing boats or tugs.

[LEGION 12]

6 minutes ago, lmagna said:

It's up to you really. It can be done either way, but after building a number of long narrow hulls over the years, (For RC use) I prefer to keep them attached to the building board for as long as possible. It is disappointing to go through the building of a hull for a destroyer or gunboat, or in this case a sub chaser and find the hull has taken the shape of a pretzel or banana. For some reason it does not seem to be as big an issue with wide beam shorter vessels like fishing boats or tugs.

Makes sense to me once I figure out what to do with the planking I will glue it back on . 

[Egilman]

47 minutes ago, LEGION 12 said:

I really appreciate you all trying to help me out

You've come to the right place brother, there is more modeling knowledge, (all genres) than the next two forums combined......

 

And it's family......

 

Oh, by the way, I have a PDF copy of the official Booklet of General Plans for this ship.... Just in case you want to see what they really were engineering wise....

Edited January 5, 2021 by Egilman

[Beef Wellington]

VTHokkiEE has given some great advice.  Looking a the planking tutorial will really help explain how to approach it, the balsa strips look quite thick compared to other kit supplied wood, and will make following the basics more important.  Planks do not naturally want to curve in 2 dimensions at once and will likely try to twist out of the intended hull shape if forced as you seem to be experiencing.  Look forward to seeing how you tackle it.

[LEGION 12]

Looks like removing a couple planks is the solution I have CA debonder and alcohol . Going to think over , took a couple more pictures in what daylight was left . 

Edited January 5, 2021 by LEGION 12

[Cathead]

Those are really helpful shots. It seems very clear now that the basic problem is not enough twist in that plank. As someone mentioned, those are thicker planks than one often sees (possibly because they're balsa), and that probably is making it harder for them to take the twist naturally. 

[LEGION 12]

Started to slowly remove the planks , taking my time . 

 

[Beef Wellington]

Good decision, if its any consolation, one learns more from correcting and redoing mistakes than doing it right the first time...at least in my experience. 

[LEGION 12]

2 planks off 2 more to go no damage to the bulwarks but don't think the planks are going to make it . I at least know how to remove parts now . 

[LEGION 12]

Planks are off just have to clean up the stringers a little . Going to see if I can find the correct length planks next . 

[popeye the sailor]

another point to make here is that the bulkheads are too far apart........there should be more of them to decrease the spacing.  you can get Obechi wood from Billings.......it's thinner and a lot more flexible.   I've never been a fan of Balsa,  mainly due to the fact that it dings real easy.  now if you don't feel like going that route,  you can resort to basswood sheet,  covering the hull frame in sections.  you will need to anchor the frame back onto the board though,  to insure that the hull will be warp free and straight.  I just did this to a Dumas PT boat.  they supply plastic sheets to cover the hull frame,  but I thought that cutting the plastic to shape would be a lot of work.  so I went with basswood sheet.  I used 1/16 so that I could get good contour of the frame.  I have a log going on this so you can see how I did it.

Edited January 9, 2021 by popeye the sailor
extra text

[LEGION 12]

10 minutes ago, popeye the sailor said:

another point to make here is that the bulkheads are too far apart........there should be more of them to decrease the spacing.  you can get Obechi wood from Billings.......it's thinner and a lot more flexible.   I've never been a fan of Balsa,  mainly due to the fact that it dings real easy.  now if you don't feel like going that route,  you can resort to basswood sheet,  covering the hull frame in sections.  you will need to anchor the frame back onto the board though,  to insure that the hull will be warp free and straight.  I just did this to a Dumas PT boat.  they supply plastic sheets to cover the hull frame,  but I thought that cutting the plastic to shape would be a lot of work.  so I went with basswood sheet.  I used 1/16 so that I could get good contour of the frame.  I have a log going on this so you can see how I did it.

Great to see you post here been watching your PT build and others for awhile with envey . If I added more bulkheads it would cause problems later with the mounting running gear , of course I could be wrong . 

[Egilman]

7 hours ago, LEGION 12 said:

Great to see you post here been watching your PT build and others for awhile with envey . If I added more bulkheads it would cause problems later with the mounting running gear , of course I could be wrong . 

Just my opinion brother, if your going to put it in the water, sheeting is the way to go for the strength, if it's going on your shelf, planking will suffice.... Either way, when finished, you won't be able to tell the difference.......

 

More bulkheads out of light ply are easy and all they do is add structural support, as far as running gear you cut out the centers of the new bulkheads to maintain hardware space....

 

Nice work so far my friend, for a first build, looks great....

 

[LEGION 12]

19 hours ago, popeye the sailor said:

another point to make here is that the bulkheads are too far apart........there should be more of them to decrease the spacing.  you can get Obechi wood from Billings.......it's thinner and a lot more flexible.   I've never been a fan of Balsa,  mainly due to the fact that it dings real easy.  now if you don't feel like going that route,  you can resort to basswood sheet,  covering the hull frame in sections.  you will need to anchor the frame back onto the board though,  to insure that the hull will be warp free and straight.  I just did this to a Dumas PT boat.  they supply plastic sheets to cover the hull frame,  but I thought that cutting the plastic to shape would be a lot of work.  so I went with basswood sheet.  I used 1/16 so that I could get good contour of the frame.  I have a log going on this so you can see how I did it.

Do you think these will work work with the hull shape I'm working with ?  

[lmagna]

If you are going to RC this ship then you need not plank or sheet the hull at all. You can fill in the areas you presently have between the existing bulkheads with expanded Styrofoam. You can source this in a number of forms and it is both easy to work with and can even be free if you look around. Then all you need to do after filling in the spaces is to sand the hull to shape using the present bulkheads as guides. When properly shaped use some spackle for a final smooth hull shape and correct errors, also sanded down to as thin a coating as you can. Then use some fiberglass cloth and resin, (Epoxy unless you left a relatively thick layer of plaster) and coat the entire exterior. This can be repeated if you wish to make the hull thicker and stronger. Then remove the excess foam from the interior and you have a waterproof hull.

 

A number of years ago I did essentially the same thing with the hull of an ocean going WWII tug in 1/48th scale and when finished just poured gasoline into the hull and the foam disappeared. Not necessarily recommended as the fumes are HORRIBLE! But I was young and in a hurry, and it was quick!😝 Probably a bit stupid as well and I had to leave it outside for a couple of days to rid it of the fumes. Ended up with an almost completely open 48" hull that never had a single leak in over five years of running in almost all conditions. Even went winter icebreaking with it a couple of times. THAT was a little hard on the bow so didn't really follow up on that idea.

 

Although it has not been run in probably twenty plus years the hull is still as solid as it was back in the day. The superstructure could use some work as it has fallen from the shelf a couple of times over the years but the hull was not affected.

 

Even if you do use planking or sheeting it would still be a good idea to coat over it with fiberglass cloth and resin though. You need not make it as heavy in that case though as the wood will give the hull all of the strength it will need.  

[LEGION 12]

15 minutes ago, lmagna said:

If you are going to RC this ship then you need not plank or sheet the hull at all. You can fill in the areas you presently have between the existing bulkheads with expanded Styrofoam. You can source this in a number of forms and it is both easy to work with and can even be free if you look around. Then all you need to do after filling in the spaces is to sand the hull to shape using the present bulkheads as guides. When properly shaped use some spackle for a final smooth hull shape and correct errors, also sanded down to as thin a coating as you can. Then use some fiberglass cloth and resin, (Epoxy unless you left a relatively thick layer of plaster) and coat the entire exterior. This can be repeated if you wish to make the hull thicker and stronger. Then remove the excess foam from the interior and you have a waterproof hull.

 

A number of years ago I did essentially the same thing with the hull of an ocean going WWII tug in 1/48th scale and when finished just poured gasoline into the hull and the foam disappeared. Not necessarily recommended as the fumes are HORRIBLE! But I was young and in a hurry, and it was quick!😝 Probably a bit stupid as well and I had to leave it outside for a couple of days to rid it of the fumes. Ended up with an almost completely open 48" hull that never had a single leak in over five years of running in almost all conditions. Even went winter icebreaking with it a couple of times. THAT was a little hard on the bow so didn't really follow up on that idea.

 

Although it has not been run in probably twenty plus years the hull is still as solid as it was back in the day. The superstructure could use some work as it has fallen from the shelf a couple of times over the years but the hull was not affected.

 

Even if you do use planking or sheeting it would still be a good idea to coat over it with fiberglass cloth and resin though. You need not make it as heavy in that case though as the wood will give the hull all of the strength it will need.  

I would love to see how that's done ! Plans call for fiberglassing the hull with 2 oz cloth once it's planked and sanded . 

[lmagna]

3 hours ago, LEGION 12 said:

Plans call for fiberglassing the hull with 2 oz cloth once it's planked and sanded . 

Should work just fine after planking. Won't tolerate much sanding before you go through the cloth though. I would be tempted to use mat at that weight. It would make repairs to thin areas easier if you sand too much.

Edited January 10, 2021 by lmagna

[LEGION 12]

19 hours ago, lmagna said:

If you are going to RC this ship then you need not plank or sheet the hull at all. You can fill in the areas you presently have between the existing bulkheads with expanded Styrofoam. You can source this in a number of forms and it is both easy to work with and can even be free if you look around. Then all you need to do after filling in the spaces is to sand the hull to shape using the present bulkheads as guides. When properly shaped use some spackle for a final smooth hull shape and correct errors, also sanded down to as thin a coating as you can. Then use some fiberglass cloth and resin, (Epoxy unless you left a relatively thick layer of plaster) and coat the entire exterior. This can be repeated if you wish to make the hull thicker and stronger. Then remove the excess foam from the interior and you have a waterproof hull.

 

A number of years ago I did essentially the same thing with the hull of an ocean going WWII tug in 1/48th scale and when finished just poured gasoline into the hull and the foam disappeared. Not necessarily recommended as the fumes are HORRIBLE! But I was young and in a hurry, and it was quick!😝 Probably a bit stupid as well and I had to leave it outside for a couple of days to rid it of the fumes. Ended up with an almost completely open 48" hull that never had a single leak in over five years of running in almost all conditions. Even went winter icebreaking with it a couple of times. THAT was a little hard on the bow so didn't really follow up on that idea.

 

Although it has not been run in probably twenty plus years the hull is still as solid as it was back in the day. The superstructure could use some work as it has fallen from the shelf a couple of times over the years but the hull was not affected.

 

Even if you do use planking or sheeting it would still be a good idea to coat over it with fiberglass cloth and resin though. You need not make it as heavy in that case though as the wood will give the hull all of the strength it will need.  

My shop walls are covered in expanded foam . 😀  

[popeye the sailor]

hi there.....just tuning in here.  yea....I'm glad you like the alternative idea.   no....you won't need to make additional bulkheads.  if you run the sections with the grain,  they should conform to the frame just fine.  I would suggest sheeting the frame two sections at a time.  using the keel as a starting point,  butting it along the keel and then wrapping it around should work out well.  trim the sections slightly past the deck line {I'm guessing there aren't any bulwarks}.......you can do the final trim work once you release it from the board.   create your joints so they share the adjoining bulkhead,  making sure they they are flush.  I cut all of the section for the PT boat by eye......some minor adjustments with the shaping before I glued them down.  what you bought there is perfect,  as the hull doesn't look very deep.......some of what I bought was 4 and 6 inches wide.   with some kits.  they supply 'rabbits' that you can cement planking or sheeting to...apparently Dumas doesn't do that.  you'll also need to find if the bow stem needs to be sanded to an apex,  as I did with the PT boat.........   one nice thing with this hull,  is that there isn't a defined chine.......you'll be able to cover it with single sheeting.   I plan to use resin on the hull,  but only the resin.....I don't use the cloth.  sometimes I could see the cloth showing through.  I figure to give it a coat of resin......sand smooth and then give it a second coat.  this should more than suffice