Building a OzRacerRV and has a lot of Qs

[Pharmer]

I have been bitten by a PDR bug. I am a novice when it comes to wood working but I think I can do it. I just purchased a OzRacerRV plan and have been studying and reading postings by AlexN and Bitingmidge. Also Michael has been very helpful through emails and his website. Past weekend, I have been shopping for tools and materials. Yes, good excuse to buy more new tools for myself. I am concerned about selection of materials since my choices are limited to what is available in Sacramento, CA, USA..
Questions
1)Plywood Hull: I went to HomeDepot (big box hardware store) and other hardware/lumber stores in search of 4mm thin plywoods but nobody has 4mm thin plywoods. Thinnest one I could find was 5mm underlayment plywood from HomeDepot. Price was very good, $10 each. But I am not sure about the finish. It looks shinny and very smooth on one side. Almost like those laminated hardwood floor material. I think I can sand it down to make surface rough so that it will stick to epoxy. Do you see any problem using underlayment plywoods for side and top parts?
2)Plywood bottom: I went to a lumber store to buy other items. They had a ¼ inch marine plywood made of Doug Fir but it was only 3 ply. I just cannot seem to find 5 ply version anywhere. But it seemed strong and may work ok.
3)Timber: I asked for Doug Fir timbers but they didn’t have any. They directed me to Western Red Cedar. It looked good and was light. They milled it down to sizes that I needed for mast, cleats, tiller and etc… But they felt weak. They will make my boat very light but not sure it they can withstand forces and pressures, especially spar / mast. I should have done more research before I went to a lumber store. According to a website, WRC is one of the weakest hardwood. Should I go with other type of wood? I just don’t want my mast to break while sailing through strong winds. Also plan to add reinforcements for an outboard. Not sure if frames and top cleats made of WRC can handle an outboard motor (3-4 hp).
4)Epoxy glue: I searched eBay and found these. http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=310181799960 Their price was good. Do you think I can use this to glue hulls and other parts?
5)Epoxy coating: Also from same company. http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=310116238243 I ordered 2 gallons for pre-coating and coating purpose. I will use above Epoxy glue for gluing.
6)MK II version has inspection ports but RV doesn’t have any. RV really doesn’t need one?

I would appreciate any comments and advices. I am still waiting for my clamps from Amazon.com and glues to get here so that I can start building mast and foils.

[Andykane]

I think you should look around for a real wood store - try and find somewhere that caters to actual woodworkers instead of homebuilders. You might also be able to get plywood shipped which I think can be a lot more reasonably priced than you might think.

I think people do use underlayment for building quick 'n dirty boats but it is definitely not ideal. Fir is also sometimes used but modern fir plywood (even marine grade) is not very good quality and tends to check/crack and generally get ugly fairly quickly.

WRC is actually a softwood, although softwood and hardwood don't actually refer to how hard the wood is. WRC glues very well but is a bit weak for spars. I know up here Home Depot does sell Douglas Fir but only in kiln dried bits that are super expensive (in the aisle with trim and stuff, not in the normal 2x4, etc lumber section).

That epoxy seems like it should work ok although the 1:1 ratio is considered inferior to the 1:2 or 1:5 ratios epoxies (something to do with the chemistry). You can probably use the same glue and thicken it yourself with a suitable filler (microfibers, colloidal sillica, sometimes wood flour (dust)). If you can find somewhere that sells West System you could use their fillers, or see if there are any stores dealing in composites and fiberglass - they should sell suitable fillers too. It's a bit late now, but if I was going for a budget epoxy I'd go with the stuff Duckworks sells since it seems to be proven. If you don't already know about them, you might find a lot of useful stuff on Duckworks including suitable epoxy fillers, hardware, and so on (sails too!). I've always been happy with the stuff I've got from them and the prices tend to be very good.


... Hopefully that wasn't too rambley

[Andykane]

I did a bit of searching and was horrified to find that there seem to be 7 Home Depots in your town (!!), but I found a few places that sound promising

Solid fir, possibly plywood:
Berry Lumber--retail & wholesale lumber products

Solid wood, they sell plywood but all looks house oriented:
Higgins Hardwoods - Douglas Fir

Good quality plywood, but would need shipping:
Marine plywood joubert okoume and baltic birch

Obviously I have no experience with these places but I've found that the key to finding good stuff is to find the smaller more specialized stores. They seem to have a better idea what you need and I always prefer not to support the big box stores if at all possible. If you could find other builders in the area (might be worth looking on the woodenboat.com forums) they could probably give you good suggestions.

[davlafont]

I did a bit of searching and was horrified to find that there seem to be 7 Home Depots in your town (!!)

They're catching up to Starbucks!

Pharmer, what's your goal for your OZRacerRV? If it's just to knock about for a couple of years while learning to sail or learning to work sailing into your life, I would think underlayment will do fine. It certainly conforms to the ethic of PDRs and MIK's Quick Canoe mindset.

The floating boxes can be serious projects worthy of the extra effort (you've seen AlexN's thread), but I suspect you're looking to get wet quickly and inexpensively.

Too bad about the lack of Doug Fir. That's what fills the HD shelves here in the Northeast.

[Pharmer]

Andykane and davlafont, Thanks for feedbacks and answers. Initially, I was searching internet to buy a small used dinghy for my kids to learn sailing and saw PDR. Yes, I probably will use it for a couple of years then build another one or graduate to GIS.
I am going to try to build one with what I have now. Unless people think that WRC is really a bad choice for spars. Some internet sites even recommend WRC for building masts. My kids and I are just going to sail this around in a lake, next to our house. Houses are all around the lake so it should be safe, even if it sinks.

I was just talking to a contractor who is going to build cabinets at my work told me that his company, Burnett & Sons does millwork and can order lumbers for me. So I do have another option.

[Tiki Pirate]

Pharmer, if you are looking for a good wood source and don't mind an hours drive you can check out Macbeath Hardwood in Berkeley, CA. They carry some marine ply(HydroTek). They only have 24x48 listed on their website - so I may be unsure if they have 4x8 sheets; but, it is worth a call. Just be sure to turn the sound down on your computer before you visit their website.

I'd just bought a set of OZracer RV plans from Duckworks a few weeks back and plan on starting a build later this summer. I need to send Mik an email for his lugsail plans.

I keep wanting a bigger boat; but, keep remembering that no registration is required for sailboats under 8' in California.

It will be a good boat to teach my 1 1/2 year old daughter to sail when she gets a little older.

Good luck with your build and fair winds.

[pdr311]

You can, and should build the boat out of what is available at your local Home Depot. I would stay away from the underlayment plywood, even if it is a good deal. If they have spruce or fir 1/4" three ply good-one-side, that is plenty strong enough. I built the prototype MkIII/OzRV with 1/8" doorskin (2.7mm) for the hull sides, deck, and airbox tops, and 1/4" fir three ply for the bottom, transoms, bulkhead and inner airbox sides. (I wanted a little more beef where I tend to kick the sides with my feet). WRC is plenty strong enough for what little framing there is. The strength is in the fillets and glass.
All I have done with my boat is sail it to the 2010 PDRacer World Championship, both the 2010 and 2011 Canadian Championships and have about 150 days of sailing in it over the last 2.5 years. It's holding up fine, but getting a little long in the tooth. For the $125 in materials, maybe I'll take another 8 hours and build another, and give this one a proper Viking burial.
Build it, love it, sail it, burn it. Repeat as often as necessary.
Rick Landreville
Rosedale B.C. Canada.

[Pharmer]

Rick, Wow!!! It's so awesome to get your feedback on this. I have been studying photos of your prototype. Yes, I am going to return underlayments and get regular plywoods instead. If you don't mind, I have a few questions regarding your prototype.

1. Did you use latex paints (white) to coat airboxes? Instead of epoxy?
2. Did you ever added any inspection ports to your airboxes? If yes, are they are on sides or top of airboxes and what size? If not, how do you know or care if water is leaking into airboxes?
3. Looks like you didn't precoat any parts. Do you recommend that I precoat before I assemble?

Thank you so much for answering and I really appreciate you for sharing photos of your prototype. Very helpful.

[pdr311]

1. Did you use latex paints (white) to coat airboxes? Instead of epoxy?
2. Did you ever added any inspection ports to your airboxes? If yes, are they are on sides or top of airboxes and what size? If not, how do you know or care if water is leaking into airboxes?
3. Looks like you didn't precoat any parts. Do you recommend that I precoat before I assemble?

.

1. I used an industrial plastic coating similar to Rustoleum to paint inside the airboxes. Not that I have a preference, I just had some leftover from another project. If I was using expensive marine plywood, I would have coated it with epoxy. That is the gold standard in coatings.

2. Yes, I installed two 6 inch screw on deck plates on the sides of the airboxes at the lowest point near the centreboard case. 6 inch is about as small as you can go and still get your hand in there to sponge out any condensation, or (heaven forbid) water. I had a significant crash in some shallow water and since then I get a cup of water in the airbox where the case is every hour I sail through the case.

3. I painted everything I could reach before I put the seat tops and deck on. Take care not to paint any surface you plan on putting glue on. Tape it off if you have to. The only exception to this is if you use epoxy, and the `wet on wet`method that Storer recommends. I find handling all those sticky parts a pain in the rump.

Rick Landreville
Rosedale, B.C. Canada.

[Pharmer]

Rick,
Thank you so much for your reply.
I am going to start the project this weekend. Yeah!!! Start with plywoods and if Mike email me the template before this weekend, then I can start making foils.
Thanks again

[Pharmer]

Finally I got all the parts ready for 3D. It looks simple but took me several weeks to get to this stage. Painfully slow. I am following instructions very carefully since I don't want to make any beginner's mistakes.

I glued transoms and tank panels over the weekend. I couldn't glue outer shells because I dropped one of the outer shells and cracked a deck cleat. Uggg... But actually it was fortunate that I didn’t glue outer shells because yesterday, I discovered a measurement issue with outer shells during the dry run. I am trying to figure out a best way to overcome that issue. Might take some epoxy fillings, sanding, and planer to resolve.


Attachment 213785

[verbertus]

Hi Pharmer,

I received your PM, but am somehow unable to reply.
Tried to reply twice, but after submitting the message, my 'sent' box remains empty.

Thank you very much for the important information you sent me.
Very kind of you!

All the best,
Bert

[Pharmer]

Bert,
Your messages did go through fine.
Good luck with your build in August. This has been a very time consuming project for a beginner like me. I spent every weekends and any available days and nights studying the plan, going through web postings, and working on this project. This forum and MIK have been very helpful by the way. Forget about doing any work around the house. My wife and kids have been very supportive about this but they don't know that I want to build another boat after this. But I have to say that I do enjoy working on this project very much and learning a lot about boat building. I may end up with fleet of boats in my back yard.

[Boatmik]

Howdy,

One hint on second boats. One chap on the now deleted original PDRacer forum mentioned how before breaching the idea of building a new boat they started buying magazines for ultralight aircraft and reading them around the house.

After a few weeks their partner said "um, what were you thinking about building something? ... maybe you should think about another boat?"

MIK

[Pharmer]

Added side panels yesterday. Next is mast partners but I am concerned since I made some modifications to bow transom in order to fit side panels. I think angle got changed. I hope I can align it correctly. Goal for this weekend is to put the bottom on and put together a mast.

Attachment 214035