Pawlonia or Western Red Cedar?

[pajeronj]

Hi there
I am going to build a nested dinghy and am trying to find out what sort of wood I use for the frame. I asked about Pawlonia but the guy said it is butt-joined. I also looked at some pine but it was finger-joined. What is a good timber for this purpose? I am in Melbourne, Victoria, Australia

[andrew allan]

Not sure what a nested dinghy is. Is it like nested side tables, where you build several and they all fit inside each other (!) or did you do a typo and mean setnet dinghy? If the latter, I have lots to offer, as I built one last year. If it is actually " nested" then I've no idea.
Andrew allan ( also in melb)

[whitewood]

hi Pajeronj
I don't know what a nested dinghy is either but as you posted in the boat building thread I assume it is a water craft. If you believe WRC is a suitable timber to build it then Paulownia would be also but your craft would be 25% lighter in weight and lighter in colour.
I don't know who you asked to supply the Paulownia but I know there are several places including my self that supply natural planks that are not jointed. PM if you want more information.
John

[Darce]

Which plans will be you using? The nested dinghies I've seen have all been made from stitch and glue plywood with no need to frames.

Stay right away from pine - unless it has the words Huon or Hoop out in front of it. Radiata is for framing houses and crappy mass produced furniture.

Western red cedar is a lovely timber, nice grain and colour and very light but I wouldn't frame a boat with it.

Paulownia is even lighter in colour with very fine grain - kind of like a hard non-fuzzy balsa. It takes stain very nicely and is ideal for strip planking but again I wouldn't frame a boat with it.

[whitewood]

"Paulownia is even lighter in colour with very fine grain - kind of like a hard non-fuzzy balsa. It takes stain very nicely and is ideal for strip planking but again I wouldn't frame a boat with it. "

Darcie I'm not a naval architect so I can't dispute your statement but you should have a look at the thread "Building Shesha a Hunter valley GIS". Paulownia was used extensively in the construction, apparently with the approval of the designer.

I wouldn't sell it to frame a 6 metre offshore power boat but for small craft it appears to be OK so long as the timber sizes are appropriate.
John

[Boatmik]

Howdy,

A note of explanation is required for the use of paulownia in Shesha the Goat Island skiff.

There are a range of timbers used in the construction of this boat with species chosen for specific function.

Most of the timber that will get direct hammering from time to time as the boat rubs up against things on the beach or wharves, or when tied down on a trailer (gunwales and inwales) are all much tougher species than Paulownia.

The Paulownia has been used in areas where
provide a glue cleat where ply joins to ply at an angle and the paulownia is well down inside the boat
As a strip built blank for the centreboard and rudder blades which is to be glassed after.

The Goat Island Skiff is a boat that is particularly suitable for this approach as most of the structural integrity is in the ply panels that make up the bulk of the boat. The job of the paulownia is to hold the two pieces of ply together in some of these places. Loads through the paulownia are distributed loads through the whole piece of ply rather than point loads. Point loads are possible of course - boat resting on a rock or hitting something, but Paulownia is either not used for vulnerable areas or is supported by other timber or glass tape.

A more traditional "plank on frame" type construction where framing is separate from the plywood would not be suitable at all. Additionally more traditional construction is based around fasteners. If the particular design relied on fasteners then paulownia could be a poor choice.

It is not a blanket recommendation for paulownia for boat framing, but used with care in the right places it can give a substantial weight saving.

I do expect paulownia use to be expanded in boats as the knowledgebase improves. I would have few concerns about using it to strip plank boats of the size most of us are doing here - kayakers have found it fine for quite heavy use and they use boats in a more extreme way than most sailing/rowing dinghies and small motorboats.

I would still have some concerns about using it for larger yachts and motor boats at this stage. I was peripherally involved in some of the larger balsa strip built boats and while the balsa was fine structurally in terms of handling the "in use" loads, there was a problem with denting. This is not a problem with smaller boats, but having a tonne or several of yacht rubbing up against something might bring the paulownia into denting territory.

So I'm keeping an eye out for good data from bigger boats as people try it.

Best wishes
Michael

[Boatmik]

My original posts on paulownia for strip planking boats are here (http://www.storerboatplans.com/Faq/faqindex.html)

[pajeronj]

Thank you all for your information
By nested dinghy I mean one that comes apart and the parts "nest" inside each other. I think "stackable" is another.
It is a Toter 2 from a fascinating man called Ken Simpson in USA. I bought the plans and intend to make it primarily out of marine ply but the framing sections are a hardwood. In the materials list it just says "1 X 2 lumber".
As you may have noticed I am a rank amatuer so I found out that WRC is used for frames and bulkheads in Australia and then I discovered Paulownia.
The Toter 2 does indeed have a rub rail so it could be in for a few thumps every now and again.
Ken's website is www.PortableBoatPlans.com (http://www.PortableBoatPlans.com)

The Toter 2 is an amazing little boat and I am keen to have a go at building one but got stuck on the type of timber.

Your assistance is greatly appreciated.
Peter

[ausie]

Selected quality Paulownia ( the quality varies dramatically in my experience) is similar to,but not as strong as Western Red Cedar & both are easy to work with & have many applications in boat building.

I have used both for the rails/nose-tail blocks in hollow wooden surfboards & some framing in plywood boats,canoes & surf skis.

My bulkheads are framed in WRC in the Jim Michalak "Ladybug" I recently finished for instance,where the WRC stiffens the bulkhead panels & provides a large gluing area when attaching bulkheads to ply sides/bottom.

For a technical summary of a comparison of the two timbers,I have attached an article written a couple of years ago by Bruce McConkey of Boatcraft Pacific,& printed in AABB.I'm sure you'll find it interesting & enlightening (no pun intended!)

Talk to the supplier whose ad I have attached.

Al.

[Mark Bowdidge]

Actually mike,
This article was written in a bias sense at the time, as Bruce was a supplier for WRC and not Paulownia and at the time there was a bit of a war between the two. Also, he states in the article that Paulownia is only 4 years old. Not true. The kiri timber imported from china is only 4 years old, but the Paulownia grown and supplied here in Oz is in actual fact 14 years old when milled. You can really see the difference between the two in their growth rings

We actually had it tested at great expense in comparison to a top peice of WRC we had at the time and supplied this as we wanted an unbias test between the two. The WRC turned up very poor numbers whereas, the paulownia gave very good results.

Just this week we had a Royal Institute of Naval Archtects Tech meeting of laminates. Paulownia was mention as an excellent timber to use in laminate construction for it's high strength to weight ratios. :2tsup:

In regards to it's brittleness, a lot of our clients have built before using WRC and have found that that statement is very erronous. Paulownia is very easy to work with and very easy to bend. Whereas, WRC (even from our past experiences building from both) we've found that WRC is very brittle and can split easy. Talking with a friend of mine in the boatbuilding industry in the US, he said all the top notch WRC is now exported to Japan for top dollar. This leaves only the rubbish behind. From this rubbish, the cream is kept and the rest exported to Oz etc. That would explain the WRC poor numbers in the test.

Its because of this test, that we now use Paulownia in most of our designs.

What it all really boils down to is, what are you using if for in a boat and how are you going to use it. To make a "blanket" statement such as Bruce given in his article above is unfortunatly... poor taste.

Hope this helps
regards
Mark
www.bowdidgemarinedesigns.com (http://www.bowdidgemarinedesigns.com)

[pajeronj]

Sorry, forgot to mention hoop pine as well. Are my choices for the bulkheads and framing wrc, paulownia or hoop pine, or are there others?

[Darce]

I'm not a naval architect, shipwright or any other formalised kind of boating dude, just one of those jack-of-all-trades and turn my hand to anything blokes.

I can see the logic which went behind the design of Ken's boats and the design briefs seem to be primarily based around cheap and easy construction. His development of tape and glue also seems based on keeping things simple and cheap.

Even his comments section focuses on how cheap these boats are to build, he even goes so far as to state that he does not want to pay the price of marine ply.

The problem is, as I see it, you get what you pay for. I can't see these boats lasting for more than a couple of years without a lot of care - far more than you would for many other construction methods.

If you're going to build a boat, any boat, you should stick to the designers guidlines unless you have the experience and knowledge to deviate. Whip down to your local hardware store and buy some external grade ply, some sticks of radiata and build your boat like he says. Don't use marine ply, don't use exotic timbers, just buy his material list.

Personally, and I can't think of any nice way to say this, I wouldn't go near the thing. There's quite a few nested boat designs available which look much nicer.

[pajeronj]

Thanks Darce, for putting into words what had been at the back of my mind anyway! Yes I noticed the emphasis on being cheap but thought I could upgrade the speccies to proper "pink" marine ply and either paulownia, wrc or hoop pine.
I suppose one of the legacies of being a rank amateur is that enthusiasm takes over the space where common sense used to sit.
I absolutely appreciate your post, Darce.
:2tsup:

Yeah maybe I should be looking at other nested designs. I have a copy of the PD Mk 2 Racer plans but got scared off by some of the woodworking manoevers I saw. I am not ready to start so who knows? I liked the PD Racer because of its versatility I just hope I have the ability to make one.
I am not really aware of any other nesteds kicking around but would appreciate any links people can give me.

Thanks again, mate.

Peter

[pajeronj]

I just dug out the PD Racer plans I bought and the timber is in imperial. Would 3/4" be 19mm? And would 7/8ths be 21mm? Does that mean I can use a strip of timber 20mm X 20mm? I wish these things were in metric!!! I don't have, or have access to, a thicknesser either. Argghhh!! All very confusing --- which is why I went to the Toter 2. I am determined to build this puddle duck but I'm not sure I understand enough to even start!!

As Einstein is reported to have said, "Make something as simple as possible - but no simpler"
:doh:

[Chief Tiff]

7/8" is a bee's genital over 22mm. I use a set of Zeus tables to convert metric to imp and back, but I'm sure you can find a similar enough conversion table via Google.
Actually, building things using imperial measurements is easy; the only time it gets a little bit tricky is when for instance you table saw or router table fence can only be set using metric measurements. So you do it the old fashioned way and stick a rule between the blade and the fence.....:D you could always go retro and use a story stick as well, that way you'll only have to measure once.

Actually you'd be surprised how much we still really use imperial sizes for everything; sheet goods are sold in 2440 X 1220mm (8" X 4") and many are sold in unusual thicknesses, 6.4mm, 12.7mm etc which are obviously 1/4" and 1/2". I think the daftest ones are the lengths of timber you buy in the hardware stores, although priced in lineal meters they are sold in feet and yards. 0.9m is... a yard. 1.2 m is ...4 feet. 5.4m is...6 yards.

If you do go down the imperial route having a calculater that can work with fractions is always handy. I prefer Casio scientifics because they also have all the trig functions I need.

[pajeronj]

I appreciate everyone's help, thank you all. I certainly have all the basic tools as advertised on the promo material but I'm going to have to wait a while to save up for the other stuff that I need. Thanks Chief, as it happens my Triton is calibrated in metric. I though that was what the 14th of February 1966 was all about. Yes I do find it really odd about the sizing of "metric" timber. It's almost like finding out there's no Santa :o.

Please have a laugh at my expense if you want to but I am not sure if 25mm timber can be used in the absence 22.7mm timber. I have never done this sort of thing before and so am not sure if the slighty larger timber size will affect the PD at all. I guess I'll also need a finger jointer (not the super glue PAR spoke of in another thread :D) after I cut up some old window frames and buzz them down.

I'll contact the people I bought the plans ff and test their patience with my silly questions :B. To contradict myself I believe the only really silly question is one that is not asked.

Thanks for your patience. I'll go away and have a think now.

[damian]

I had a quick look at the boat.

1. I wouldn't use paulownia or WRC for the frames. The problem you'll get is the bolts will crush and tear the timber over time.

2. Generally timber strength is relative to it's density. I'd be looking for a medium timber like hoop or oregon (aka douglas fir) or something about the 600 - 700 kg/m^3 range. It is cheaper than wrc and won't add too much to your overall weight. Should be easy to find without any joints in the sizes you'll need.

3. Durability. WEST system and a good paint or UV filterning varnish.

4. Ply, someting without voids, and water and boil proof. Doesn't have to be rolls royce marine grade. Australian hoop marine ply would be ideal. Read the threads on asian marine ply, it's not always good quality.

[Boatmik]

Howdy, One caution with converting is while it is sensible to convert measurements when ordering timber it is best not to convert when building. Converting building measurements usually results in a bunch of cascading errors that mean really big mistakes as you get to the other end of the boat. One Goat Island Skiff ended up with the forward bulhead out of vertical by over an inch (25mm) because of converting the drawings with a calculator or table. Converting the material list is fine. Unless there are specific notices in the plan to say a particular thickness must be accurate, most sizes are nominal - at least for holding the hull together. So 3/4 square can mean 19mm square but a mm or so each side is not going to hurt. One place to be pretty spot on is the chine logs as they only just make the bend if they are 19 x 19 - on my PDR plan version I ended up defining them as laminated. Where it might count is with parts of the boat taking particular load, mast and other spars, centreboard, leeboard - maybe bits that define fits like centreboard and rudder case spacers/headlogs. Most bits of timber that form part of the hull are nominal, but higher loaded parts like the above often need to be pretty close. Use nominal sizing but if in doubt give the designer or plans agent a yell. Michael

[Boatmik]

my paragraphing has disappeared ... how strange.

[Mark Bowdidge]

I wouldn't use paulownia or WRC for the frames. The problem you'll get is the bolts will crush and tear the timber over time.



I totally agree.

[mob]

...as it happens my Triton is calibrated in metric. I though that was what the 14th of February 1966 was all about.

No, that was the decimalization of our currency. Did I spell that right?

[pajeronj]

:U Heh heh, yes you're right mob, it was indeed the changing of our currency. Like I say, maybe I'll go away and have a big think about this. My triton mk 3 will do finger joints and yes Mik, it is a good idea to get the other bits done before attempting construction of the hull. I could also have a go at scarfing?

Given my total lack of experience and the unknowable outcome of this project I think I'll just sail it in shallow lakes. That way when my big feet go through the floor I can still walk around and people will think I'm sailing.
:wave:

[damian]

Funny.

Small boats aren't critical for strength, so putting your feet through the floor or it falling in two won't be your problem. It may leak.

Your first problem is if the measurements are a bit off as you make bits when you come to fit it all together it won't. Ply comes up a bit short, or the nesting parts don't line up.

The second problem is it'll gradually look more and more ragged over time. Eventually stuff will start to fail.

Personally I think it's an excellant starter project, provided your ready for an ugly outcome or a relatively shortlived boat. Thing is it doesn't require much money/materials and time, and the potential to drown in a small boat is less because you are less likely to try to get to new zealand in it.

You may build a wonderful boat, just don't expect that outcome first try. You could build one from rubbish, make all your mistakes, then redo it with better materials. Just a thought...

[pajeronj]

Yes, good thought, Damian. I have got on to some cheap tassie oak, I'll just trim the little blighters down to plan size and have a go from there. Probably best not to stress about it. If all else fails I will call it "Book Case".

You have all been very helpful, thank you!!:2tsup:

I'll let you know how I go, I'll try and get a few sticks done this weekend. At least if I cut the timber and mock it up I'll hopefully begin to get a "sense" of the boat.
The PD Racer has just got so much going for it for me. I like to sail (used to have a 20' Sunmaid), and I fancy sneaking into little lakes and paddling or small outboarding. The PD should fit on my roof rack. I'll try and keep looking on the positive.

Peter

[andrew allan]

Pajeronj,

I'm not sure of your underlying basis for wanting a boat, so this post may be helpful, or unhelpful!

I built my first boat 2yrs ago, which was a stitch and glue John Welsford design Setnet/Golden Bay dinghy. I had previously had no particular interest in boating, or boat building (although have an interest in cabinet-making), and it seemed like a nice project to do with my eldest daughter. It went together very well, and was a fun project (although her interest diminished quickly due to increasing study commitments). It probably cost me about $800 all up, which I thought was a pretty cheap boat, and we've had a lot of fun in it. I've built it as a Setnet rowing style dinghy (with a larger foredeck/forward locker, but the Golden Bay version is a gaff rigged sailing version.

Since then I bought an old fiberglass speedboat hull on ebay for $100 to do up ( I wanted a bigger boat.....!). Although the transom, floor and subfloor need replacing, the material cost of doing this myself would be about $500, and then seats/windscreen can be made/bought reasonably easily to get a good boat hull for under a $1000. Major cost here is going to be a motor.

Sadly another boat project came up recently which I bought - an 18' wooden half cabin, for $650, with trailer. It needs almost no work. I previously looked around at building a plywood half cabin , and it would have cost about $7K in materials alone. I'm now in the process of selling the speedboat hull, as I don't need 2 big boats (ie there's a cheap Swiftcraft Runabout on ebay at the moment, and I've done most of the hard stuff of cutting out the transom and floor).

What I'm getting at is that whilst it is extremely fulfilling to build a boat, and it is cheap compared to buying a new boat, if all you want is a boat to get on the water, it may be cheaper to look around on ebay for a pre-loved one. And lastly, remember that outboard motors are comparatively expensive.

[pajeronj]

Thank you, Andrew I found it very helpful. I actually already have a 3.4 metre tinny that sits on top of my camper (photo attached ... I think). We blew up the old Chrysler motor last trip (not a difficult thing to do!) so we're going to get another motor for it around tax refund time. :B

I sold the Sunmaid because we were living in Bairnsdale at the time at it was just perfect. Then we were transferred to Melbourne and I was fearful of Port Phillip Bay so we sold the Sunmaid. :C

Maybe your observation is very accurate, maybe I just need a dinghy that can sail and motor; something that needs minimal repairs? The tinny is great for fishing and stooging about and could even venture out on the bay in the right conditions. It's funny isn't it, I wouldn't take a 20 ft yacht out but will happily go out in an 11'3" ally. :doh:

What I do know is after listening to what people have been saying is there is more to building a boat like Puddle Duck or even the Toter 2 than meets the eye. Maybe after spending $900 on materials and ending up with something that looks and sails like a dismantled gasometer through poor construction, I would have been better off with something that just needed some TLC, glassing and paint. It's a shame I can't sail the tinny!

I don't know if I have the requisite skill so there's more to think about.

Thanks Andrew your post was much appreciated.

[Darce]

There seems to be a recurring theme in your posts... lack of skill.

Skill is the result of making mistakes and learning how to;
a. Recognise the mistake :oo:
b. Not repeat it :no:
c. Solve the problem and rectify it :2tsup:

You'll be amazed at how big a blooper can be fixed with epoxy. So long as both sides of the boat are roughly the same size and there's only the big hole at the top for putting people and the esky in the boat you'll be right. Maybe it won't win prizes at the Royal Show, but you'll learn heaps in the making of your first boat and may even get the bug - ending up with a fleet!

So don't worry about your lack of skill, just grab a camera and take pics when you're in doubt. We'll all have a good chuckle at your expense and then figure a way to help you out.

Oh, and tools? It's far easier for someone new to the game to destroy a good sheet of ply with a bandsaw than with a jigsaw. Don't have a jigsaw? Use a coping saw and muscle... slower and much more accurate again. If you need to do a particular task and no idea which tool to uses, give us another chuckle moment and we'll come up with something .

The main thing is... give it a go. It's unlikely you'll regret it

[pajeronj]

OK? You're on! I'll grab some of that tassie oak and start with the framing. Still not sure which boat I'll build. Maybe if it won't win a prize at the Royal Show I might start off with the Toter (mit marine ply), then graduate to the PD.

Thanks :D

Peter

[andrew allan]

Perhaps then look at some of John Welsford's simpler boat designs - as I said the Setnet/Golden Bay dinghy can be built as a sailing boat or rowing/motoring dinghy. Google his site, and you can check out the basic plans there - there is an easily laminated stem, 3 simple cross frames, a simple transom (which needs to be modified if you want to use a small outboard), plywood sides and flat bottom, and then the seats/bulkhead/gunwhales etc support the whole structure. I built mine using marine ply, but in hindsight a cheaper ply would have been fine. Frames were built out of redwood, coz I was given some, but pine would have ben fine. I did my gunwhales with WRC, which I had from some old skirting boards, but it is too soft and would have been better with KD hardwood.

In terms of tools, I used a jigsaw for cutting the shapes, a plane for making the skarf joints in the ply (although you could butt join them using your triton), and a small plane and spoke shave for the rest, and my Mk 2 triton for cross sawing the frames ( a handsaw would have done this).

In planning and pricing other boat projects, it would seem that the cost of plywood/wood for a boat is similar to the cost of epoxy/fiberglass tape/cloth and paint, FYI.

Beyond this, if you really want to sail, I have a great NS14 skiff which I need to sell. A patient (inconveniently, quirky as this may seem) gave it to me just before I was going to start building the . I decided to do up the NS14 first, which is probably why my daughter lost interest in the Setnet. I've replaced the bulkeads and foredeck, and re-rigged it, and took it out one day for a very successful sail, but I really have no interest in sailing, and, as I seem to be becoming an "Admiral" in terms of numbers of boats owned, it will need to go too. If interested, let me know. By the by, I'm in Camberwell, which is probably not on my profile.

I suspect you'd be better building something like the Setnet/Golden Bay dinghy, and don't disservice yourself in terms of lack of skills. If you want to do anything in life, you can, and forums like these provide any additional support you may need.

Other simple designs come up from time to time in the mag "Wooden Boat".

A

[andrew allan]

I was putting together my response when Darce responded - I agree with him entirely. Just get out there and do it, and forget you "lack of skills" . We are all here to add to your journey, if you need us.

[damian]

Yes what Darce said. This assumes you WANT to build. If you don't want to BUILD then buy. Otherwise it makes no sense.

As I said above you can get ply on ebay for $13 a sheet, and buy some cheap but unjointed timber (no finger joints please). Scout around the timber yards and ask if they have anything lying around they want to ditch cheap. Build a boat that appeals to you, but avoid designes that are difficult to start with. There are MANY MANY options in small boats. LOTS! I mean LOTS! Some are hard builds many aren't. Then paint it. The first one will be a disaster, maybe, but you should be able to tack it together for $100 or so. See it as a temporary boat and a learning experience, then make your second one wonderful :)

By the way you can sail your tinny if you want to, just rig it conservatively and add a rudder and leeboard. I didn't say it'd sail well, but you can sail nearly anything. As for Port Phillip Bay I've looked at it and I'd be sticking close to shore and being picky about where I went. There are some wicked rips and swells in that body of water.

Finally I picked up a 12' fiberglass sailing hull on ebay a while back $150ish. I added a windsurfer rig and daggerboard and rudder for about another $60. That hull will take a small outboard. If what you want is a sail boat second hand is cheaper than building.

Remeber to have fun.

[woodeneye]

Darcie I'm not a naval architect so I can't dispute your statement but you should have a look at the thread "Building Shesha a Hunter valley GIS". Paulownia was used extensively in the construction, apparently with the approval of the designer.

I wouldn't sell it to frame a 6 metre offshore power boat but for small craft it appears to be OK so long as the timber sizes are appropriate.
John

It's no secret that I'm a fan of Paulownia, but as Michael has mentioned in his post, much of its use was in places where the Paulownia is not taking full loads and the loads are distributed through adjoining timbers. In the Goat Island Skiff, the "frames" are essentially functioning to increase the gluing surface area at the attachment points. Paulownia is ideal for this and considerable weight savings are possible.

However, I think we will soon start to see expanded use of Paulownia in boats by incorporating it in composite construction. By composite, I mean ply/paulownia sandwich, which can make very strong structures, very cheaply.

Elsewhere in this thread Paulownia was discounted in places where bolts and screws might be used, but with a little bit of thinking of the possibilities, perhaps a ply/paulownia composite would work very well in these situations?

Ian Howick is building a GIS in Queenstown NZ. http://www.woodworkforums.com/f169/gis-build-queenstown-new-zealand-115452/. He is taking the use of Paulownia further than I did, by incorporating it into a composite with lightweight marine ply, ie. to stiffen the transom, where I used solid Hoop Pine. He also has plans to use it more extensively in gunwales/inwales, which will be capped, again, possibly with marine ply or a hardwood.

With more traditional timbers becoming increasingly scarce and cost prohibitive, I think it's important that designers and builders start thinking along such lines. Michael Storer is one of those designers who does think along such lines, and is open to discussing ways of incorporating these sorts of possibilities into his designs.

Plastic is not always fantastic, and nowadays it's very costly to incorporate carbon anywhere into a boat. Paulownia, besides just being light in weight, easy to work and quite cheap, has other very desirable properties which supports its wider use in marine environments.

[damian]

Your quite right of course, but the context of this specific discussion was a first time boatbuilder presumably on a budget and using readily available materials.

You will see elsewhere I started a thread looking for straight paulownia plywood for boatbuilding. My intention was a glass sandwich approach. There was some talk of the material being supplied from china but I haven't resolved that yet. Getting stronger plys (plies?) on the faces is a good idea but it depends on what your building. That transome sounds like an excellent application, but say your building tortured ply hull skins I think the straight p' and glass would be better. Could be a VERY cost effective skin.

Anyway, as always remember to have fun :D

[Cliff Rogers]

I just dug out the PD Racer plans I bought and the timber is in imperial. ....
That is strange, my copy has the metric page incorporated in the main plans at page 3 & the imperial page is a separate document.

[anewhouse]

It's no secret that I'm a fan of Paulownia, but as Michael has mentioned in his post, much of its use was in places where the Paulownia is not taking full loads and the loads are distributed through adjoining timbers.
... ... ... ... ...

However, I think we will soon start to see expanded use of Paulownia in boats by incorporating it in composite construction. By composite, I mean ply/paulownia sandwich, which can make very strong structures, very cheaply.
.. ... ... ... ...

Paulownia, besides just being light in weight, easy to work and quite cheap, has other very desirable properties which supports its wider use in marine environments.

I am also a big fan of Paulownia, but I am also using it as the core of composite construction to make kayaks. They are lighter than kayaks built with WRC.

If they were able to build Mosquitoes during WWII using ply skins with balsa core, i think my kayaks with fibreglass skin and paulownia core will last the distance. :U

For those of you who are skeptical about the Mosquito, have a look at this clip from 1944.

[pajeronj]

No you're quite right, Cliff. Let's hope things improve. Is there really 84 metres of timber in the PD? As well as the ply sheets?

[Cliff Rogers]

I added it up to 54m. I have/had almost enough hoop for two ducks rough sawn in packs in a container but I pinched some to make a the Quick Canoe.

[Mark Bowdidge]

However, I think we will soon start to see expanded use of Paulownia in boats by incorporating it in composite construction. By composite, I mean ply/paulownia sandwich, which can make very strong structures, very cheaply.

With more traditional timbers becoming increasingly scarce and cost prohibitive, I think it's important that designers and builders start thinking along such lines.


G'day,
Here's just a few examples for using paulownia in our designs. Its really easy to work with and overall, when compared to typical plywood construction, it works out to be the same in costings. :2tsup:

Also, many of our clients are first time boat builders and all have commented on just how easy the whole "strip planking/ glassing" is, not as they first thought being complicated or hard.

Hope this helps out
regards
Mark

Con's SportzMaster 19 - Bowdidge Marine Designs

http://i634.photobucket.com/albums/uu69/bowdidge/Cons%20SportzMaster%2019/005-1.jpg

http://i634.photobucket.com/albums/uu69/bowdidge/Cons%20SportzMaster%2019/002-4.jpg

http://i634.photobucket.com/albums/uu69/bowdidge/Cons%20SportzMaster%2019/037.jpg

http://i634.photobucket.com/albums/uu69/bowdidge/Cons%20SportzMaster%2019/008-3.jpg

http://i634.photobucket.com/albums/uu69/bowdidge/Cons%20SportzMaster%2019/001-4.jpg



Tony's Cruise Control 5.2 - Bowdidge Marine Designs

http://i634.photobucket.com/albums/uu69/bowdidge/Tonys%20Cruise%20Control/P1000199.jpg

http://i634.photobucket.com/albums/uu69/bowdidge/Tonys%20Cruise%20Control/P1000197.jpg

[woodeneye]

That's awesome. Thanks for the pics Mark!

Do you have any examples at all of Paulownia used in a composite way?

[Mark Bowdidge]

G'day Woodeneye,
These are composite designs, not timber designs. The paulownia is only a core with several layers of 450 gm DB laminates both inside and outside. If you look carefully at the picture below (outside of hull) you see see the various layers of the laminates. On the next picture you see see the the first entire laminate being laid on top of the keel and chine tabbing laminate.
You can see a lot more of this type of boatbuilding here:

"http://www.freeforum101.com/oceansky/index.php?mforum=oceansky"

Hope this helps.
Mark

http://i634.photobucket.com/albums/uu69/bowdidge/Cons%20SportzMaster%2019/Copyof007.jpg



http://i634.photobucket.com/albums/uu69/bowdidge/Cons%20SportzMaster%2019/002-6.jpg

[Cliff Rogers]

Wow! :2tsup:

[Mark Bowdidge]

Glad you liked it Cliff.
That was just a few power boats in paulownia strip plank composite.

For those who love the sailing side, here's another one of our designs, using the same method, material and construction. We'll have more sailing designs coming soon

As you can see, it a very easy form of construction, with NO MESS :2tsup:

If you have any questions, please feel free to ask. :)

Hope this helps
regards
Mark

Morgans Sportz 16

http://i634.photobucket.com/albums/uu69/bowdidge/Morgans%20Sportz%2016/IMGP2282.jpg

http://i634.photobucket.com/albums/uu69/bowdidge/Morgans%20Sportz%2016/IMGP2286.jpg

http://i634.photobucket.com/albums/uu69/bowdidge/Morgans%20Sportz%2016/IMGP2314.jpg

http://i634.photobucket.com/albums/uu69/bowdidge/Morgans%20Sportz%2016/IMGP2317.jpg

http://i634.photobucket.com/albums/uu69/bowdidge/Morgans%20Sportz%2016/IMGP3051.jpg

http://i634.photobucket.com/albums/uu69/bowdidge/Morgans%20Sportz%2016/IMGP3020.jpg

[woodeneye]

Aaah, I'm with you now Mark:doh: I'm not familiar with that type of construction, so thanks for the edjumakation :U

Very nice. This is what I wanted to see and hear. I really think you're on the right track with this concept.

[anewhouse]

A similar technique to Mark's works well on a smaller scale.

Kayaks need only one layer of 19 x 5 mm Paulownia strips and one layer inside and out of 125 gsm glass.

With that technique, it is easy to produce a very tough 4.5 metre kayak weighing just over 10 kg.

[woodeneye]

What more can I say? Absolutely stunning! I'll have to build me one of those some day.

By the way, do you use epoxy to bond the strips?

[pajeronj]

Your quite right of course, but the context of this specific discussion was a first time boatbuilder presumably on a budget and using readily available materials.


Yes you're right, Damian. I am going to try and pick pieces out of the PDRacer plans and build then individually. I managed to miss the fact that there were metric plans and then over counted the amount of timber used so I reckon I'm going pretty good, yeah? Meh!

I agree that the only way to learn is to make mistakes and learn from them. They say to err is human, well I know then that I am a very human person.
Peter

[Darce]

To err is human, to argh is pirate

sorry, couldn't help myself

[damian]

Oh now THAT is funny!

[pajeronj]

OK? Time for your first laugh. I started to build another saw horse so I could get a start with the PDRacer and my trusty blue Bosch cordless gave up! A puff of smoke out the motor vents and I cannot recharge the batteries. It's not started well has it? I took the advice and went to the local timber shop and saw (looked at, that is) some hoop pine. Now all I have to do is go and buy another cordless and I'm away. Heh heh.:(

[damian]

That is poor luck. I've got a bosch blue corded drill that I've been abusing for 15 years. I've just about destroyed the chuck but it still keeps rattling along.

I doubt anyone will be laughing AT you, we might laugh WITH you :D

[Darce]

Budget tools? Go Ryobi +1 series. Great tools for the price and you needn't pay the extra for another battery if you have a couple. I bought the pack which came with a circular saw, sabre saw, drill and torch (pointless I thought - until I needed one). Now I have the trimmer router - fantastic tool, torque driver - even better tool, grinder and jigsaw. They all use the same batteries and the two I have last me a solid day of work.

[pajeronj]

OK, been off the air through illness. I bought an AEG 18V li-ion. Tested it with a timber screw into one of my saw horses and it would have gone right through if I hadn't let go of the trigger - woo hoo.:D
OK now for the timber. I'm off to Matthews timber in Mitcham if I get a minute next Sat and see what I can rustle up.

[sydchesson]

Highpoint Timbers / Photo Gallery "http://www.highpointtimber.com.au/gallery/gallery.html"

You will see real applications of Paulownia.

Regards,


Syd Chesson

[pajeronj]

Thanks Syd
In a peverse twist of circumstance my wife has ogled my considerations of Paulownia and now wants to half-clad the walls in the loungeroom with it. I guess it can be stained? Mind you this post should be in a different place so I apologise for that.
:?

[woodeneye]

Thanks Syd
In a peverse twist of circumstance my wife has ogled my considerations of Paulownia and now wants to half-clad the walls in the loungeroom with it. I guess it can be stained? Mind you this post should be in a different place so I apologise for that.
:?

Rest assured that Paulownia takes a stain beautifully!

[Darce]

Thanks Syd
In a peverse twist of circumstance my wife has ogled my considerations of Paulownia and now wants to half-clad the walls in the loungeroom with it. I guess it can be stained? Mind you this post should be in a different place so I apologise for that.
:?

Oh dear... such a shame your measurements for the cladding were out just enough that you ended up with sufficient spare to make a boat with ;)

[andrew allan]

There's another place down in Moorabin direction which sells Paulonia, predominantly used for wooden shutters - google "paulonia paradise". May your wife would like to use wooden shutters to "clad" the upper half of the walls, where the windows are, and whilst getting the shutters you can get some proper boat type timber.

I got onto Paulonia Paradise via another forum www.board.net.au (http://www.board.net.au), which relates to vintage boats in Oz, and one of the members there used to be a partner in that business. Certainly the chap there was very helpful. I didn't end up using any, as I sold the "project" hull and bought another one, which needs no significant work............perhaps, then, not actually defined as a "project"??!

A

[Mark Bowdidge]

Paulwonia Paradise or Port philllip plantation Shutters (same company) is the company whom we deal with in regards to our strip plank designs. :2tsup:

Dave and Sue are their names. Very nice couple and also very helpful
regards
Mark
Bowdidge Marine Designs