An Ilur in New York

[jlamarca96]

There are several great threads here and elsewhere online about Ilur building projects, but I figured one more can’t hurt!

After seeing Mike Owen’s Nimbus at the Mystic boat show (thanks Michael for documenting your project and answering my questions), and watching Roger Barnes’s videos on YouTube (thanks Roger for making such great videos and advocating for dinghy cruising), I settled on building an Ilur.

Mr. Vivier’s plans for the “Classic” version of this boat offer a few choices, and I’m now trying to make final decisions and buy some wood. Here’s what I am thinking:

• Clinker plywood, glued along the laps.
• Steam bent frames, attached with rivets.
• Possibly double the number of frames – I may install frames at the stations first and see how stiff the hull is before deciding whether to install the additional frames.
• Sapele plywood for the planks, bulkheads, rudder and CB. Sapele lumber for the backbone, stems and transom (seems to be cheaper than softwood these days), solid Sapele sheerstrake, undecided on wood for the thwarts, floorboards and other parts that come later in the process.
• Bright finish sheerstrake and interior (I know, it will be a pain to varnish and maintain – we’ll see after a few years).

Below is a picture of the building frame. Very easy to make following FV’s plans. I haven’t leveled it yet.

Questions and advice are welcome!

Jeff

PXL_20220804_222946950.jpg

[Toxophilite]

Re: An Ilur in New York

Cool. Lovely boat the illur and those Roger Barnes videos are great

[neil.henderson]

Re: An Ilur in New York

Hi Jeff,
Yes, the Illur is lovely - I haven't built one though I have just finished my 3rd glued clinker hull - a few suggestions:-
a) Decide which glue you will use - I use Wests epoxy & non of my joints have popped yet
b) Why steam bend frames (ribs?) into the hull? I am building a 19' 6" Caledonia Yawl and it will have no ribs/frames in the hull. Once you get the knees, floors, breasthook and inwale into the hull it is stiff imho. Steam bend ribs in if you want to - but it is work and suggest you laminate them.
c) Does your strong back bend or twist at all? Suspect it might do at the moment - adding some long diagonals will stiffen it up. Good idea to avoid any movement in the strong back.
d) Subscribe to Off Center Harbor and watch Geoff Kerr's videos on glued clinker building - his techniques are extremely useful and can help avoid pain!!
e) Buy good plywood - the lowercost stuff will drive you crackers

f) Learn how to sharpen blades if you're not sure how to do this now - a sharp plane makes the rolling bevel a joy :-)
g) Have a lot of fun, enjoy the build and position a chair at an appropriate spot to spend time admiring your wonderful handiwork.

This is my Gannet - just after flip.
IMG_1450.jpg
Good Luck and enjoy Regards Neil

[Andrew Donald]

Re: An Ilur in New York

Steam bending frames in and riveting them does not fit the epoxy-builders code of ethics. “Seal all wood and lessen the numbers of piercings”

Stick to the designers scantlings - do not put extra frames - all you’re doing is increasing weight, work, and making maintenance a real chore.

I agree with Neil - make the strongback stronger. You’ll be climbing on it and creating odd high forces on it. Fasten it to floor if you can( liquid nails?)

[jlamarca96]

Re: An Ilur in New York

Thanks Neil and Andrew for those suggestions.

After I level the building frame, I'm going to reinforce it until it doesn't flex. It's 2x8 doug fir so pretty stout already. Then I'll glue the legs to the floor with construction adhesive.

I plan on using West epoxy - I've used it for various little repairs so I'm going to stick with it.

I've watched Geoff Kerr's excellent videos on the Caledonia Yawl as well (I came very close to choosing that design, have the plans, but ultimately decided on the Ilur for several reasons, not least of which is that my garage is 18' x 18' so the CY would have to go in diagonal).

Now, the frames... I am still hemming and hawing about the frames. Are they necessary? The CY doesn't have them and the plans call for 9mm ply just like the Ilur. But I like to defer to the plans when in doubt, so I'm going to put in frames. But - laminated or steam bent? I'm not convinced that steam bent will be more work. Laminating requires laminating of course, then planing the sides, then as far as I understand, finding bevels for every plank at every frame, then cutting notches for the laps and beveling each notch to fit the curve of each plank so it can be glued in. That sounds like a lot of work. Maybe I misunderstand - maybe you just lay in fair-curved laminated frames and don't bother beveling them. But then you'd likely have to rivet them instead of gluing, and in that case riveting in steam bent frames is likely easier. And for me, it's not all about what's easiest. I want to get some practice steam bending, because after this boat's done I'll be building two skin-on-frame canoes with steam bent ribs. I also prefer the look of the bent frames vs the chunkier laminated/beveled ones. I don't mind riveting. As for the rivets potentially allowing water in, I'm willing to take that risk. I think there will be enough epoxy all around to keep the water out. For me the biggest disadvantage of steam bent frames is those gaps between the planks - sanding, epoxying, varnishing, cleaning... I tell myself that there are only so many of those joints that are visible above the floorboards.

As for doubling the frames - Vivier does give it as an option if using steam bent frames. But you've both made good points for not making my life harder by doing so.

Neil, that Gannet is beautiful - very fair planking and nice paint job!

[neil.henderson]

Re: An Ilur in New York

Steam bending is a lot of fun, I built a steaming box out of 12mm cheap ply & some pine framing in half a day - with dowels pushed in so that the timber being steamed does not lie on the floor of the box - need steam all around. For steam production I bought a wallpaper stripper from Bunnings (local low cost hardware) and it comes with the tubing to feed the steam into the box. Steam for 1 hour per inch of thickness approximately. And use good thick gloves - steamed timber is heckydarn hot!

I think the planking of my CY is better that the Gannet - seems I might be learning patience............................
IMG_20220623_122230.jpg

[jlamarca96]

Re: An Ilur in New York

So, I haven’t posted here since August, but the Ilur project is under way again after recovering from surgery to repair an injury I sustained while receiving delivery of the marine plywood.

One challenge is getting the most out of the lumber and minimizing waste. Vivier gives a complete list of all the hardwood scantlings in his plan instructions, and I used those to lay out on graph paper where various parts would be cut from the four boards I bought. Hardwoods like sapele usually come in random widths and lengths, so you don’t know until you get to the lumber store what board dimensions you’ll have to work with. I taped graph paper together so that I could draw the boards at one inch per grid box. (The luan patterns of the stem and transom knee are acting as paperweights in the photo.)

PXL_20230427_215448334.jpg

I made cardboard patterns of the stem parts so that I could work out how to squeeze them into boards that were ripped down to 13” to fit through my thickness planer.

PXL_20230427_215152879.jpg

One thing I haven’t decided regarding both the transom knee and the stem is whether to shape the parts to their final dimensions and then glue, or whether to rough cut each part, then glue, then shape the edges. I’m leaning toward the latter, since it will save me from having to perfectly line up the edges, and from having to shape the edges of each layer separately (transom knee is two layers, stem is three). I’ve seen some builders do the former though, using a form with blocks to clamp the final-shaped parts into place for gluing.

I’m making the transom out of five boards. I had wide enough boards to make it from two or three boards, but I saw it suggested that more boards allows less chance of cupping. In any case, I thought that 5” wide transom boards would be better aesthetically, because they’re proportional to the width of the planks. (I haven’t arranged the boards in the photo for grain orientation – they still need to be planed down another few mm to get to the specified thickness.)

PXL_20230427_215747692.jpg

I’m going to do splined joints for the transom. I’m planning on carving out only the bottom of the transom – enough for the first four planks – before attaching it to the building frame, so that I can use the offcut area to help position and firmly hold it in place.

Now I’m just waiting for temps to get into the 60s before I plane to final thickness and start playing with epoxy.

[Rich Jones]

Re: An Ilur in New York

Looking good!
That lumber looks beautiful.

[Ben Fuller]

Re: An Ilur in New York

One of the real advantages of having frames in a glued lap boat is that it makes installing the interior much easier with a riser on to which you land thwarts. In my Harrier they've not shown to be a problem in fifteen or so years.

[neil.henderson]

Re: An Ilur in New York

Hi, sorry to hear of your plywood injury. Your question about shaping before gluing, or afterwards. I find it a lot easier to shape items like stems, knees etc....... on the workbench rather than on the boat because access on the boat can be difficult & painful. I tend to shape at least 80-90% on the workbench and plan to do final tuning after it is glued in place. Though other items like rolling bevels on the strake edges are I do 100% on the boat. So, like many things in boat building - it depends.........................
Enjoy the build. Do you have John Brooks and Ruth Ann-Hill or Greg Rossels books? They are useful reference books that I use when I'm trying to figure out how to do stuff & what recommendations there are.

Regards Neil

[jlamarca96]

Re: An Ilur in New York

Ben, yeah I am going to do steam-bent frames, riveted in. I might do the first of three epoxy coats on the inside of the hull before putting in the frames (at least up to the sheerstrake since the frames go in before the gunwales).

Neil, I will do most of the shaping before installing on the boat, but there are a few components in the Ilur that are made from multiple pieces of hardwood, so I've got to decide whether to shape each of those pieces before gluing them together, or glue them together rough-cut and then shape the whole part (stem, transom knee) before installing it in the boat. I have both books you mentioned and they're both great and are my main reference books.

[Michael_Owen]

Re: An Ilur in New York

Hey Jeff!
Glad to hear another Ilur build is under way. I'm doing some spring projects like varnish and paint before getting in the water soon!

I would recommend leaving your pieces for glued-up bits like the stem and knee a little over-sized and then shape after glue-up. That works for me.
The steamed frames were fun and challenging. I stuck the bottom end of a hot frame against the keelson and then pounded down on the upper end with a small sledge hammer, then clamped the upper end to the sheer plank.

If I could do it over, I would get the bottom end braced against the keelson, and using my feet on the frame, over-bend it a bit as you "walk" up the side of the boat.
Then clamp at the sheer.

Mine don't touch the hull everywhere. But it was my first time, and with most frames riveted to most laps, plus epoxy along the laps and several bulkheads, the boat is plenty strong!

I also wish I had put the frame at Sta.2 forward of the lazarette bulkhead. Mine is inside the lazarette, and is a place where water could/can collect.

But that's all a ways down the line. Good luck, and feel free to ask any questions!

Mike

[jlamarca96]

The transom knee was my fist time using epoxy on anything more than a small repair. It’s messy stuff! I’ll be careful from now on about creating excess squeeze-out. I also took the opportunity to read up about epoxy safety. Apparently, uncured resins and hardeners contain a highly toxic/carcinogenic chemical called bisphenol A diglycidyl ether (“BADGE”), which is suspected of being much worse than BPA, but is not well studied. My takeaway is that a) you need to be extremely careful about not touching or spreading unmixed or uncured epoxy, and b) you should not sand or scrape or saw into epoxy until it is completely and fully cured (not just hardened), which means at least a week after mixing. (You would obviously wear a respirator, but the dust would still get onto your skin and into your hair and eyes.) If anyone who’s knowledgeable about this risk would like to comment, I’d like to learn more. Sometimes harmful chemicals are widely used for a long time before their hazards become well known.
transom knee.jpg

[jlamarca96]

I wondered in an earlier post whether it was better to cut the transom knee and stem to final shape before or after gluing the layers together. I decided to glue the layers together, then cut to the pattern. This worked well with the transom knee, which has two layers. Here it is cut to shape:

transom knee final.jpg


I did the same with the stem, but I didn’t leave myself much excess on any of the six pieces. This created a major challenge: it was very difficult to fit all six pieces simultaneously within the perimeter of the pattern – and hold them in place while I glued them up. I ended up butt jointing the two pieces of each layer together so that I would be gluing three independent pieces instead of six, and then I final cut the keel notch in each layer and positioned them against a block for the glue up.


stem glued.jpg


stem glue block.jpg


After the epoxy cured for at least a week, I punched a hole in the side table of my table saw to make a router table (just had to purchase the rectangular base plate for the router) and used a long pattern bit with the bearing at the end to cut the final shape of the stem to the pattern.


stem router table.jpg


When you're using a router with a pattern, you have to take a lot of care to make sure the pattern doesn't shift or flex as you move the bearing along the edge of the pattern. That's why I've got some nails in there, and I have double sided tape in a few spots too.

[neil.henderson]

Hi, yes if you are making laminated pieces (stems, knees, ribs, breasthooks, tiller, etc..........) for a boat I tend to cut out the layers of timber slightly larger than the template, glue all the layers together, and then trim the whole lot after the glue is well set. I find it a lot easier to do the final shaping of the laminated element before gluing it into the boat - especially router work.
Good luck the build.

Regards Neil