BoatBuilding Cutting the Frames

BoatBuilding - Cutting the Frames
Originally uploaded by OzzyC.

Over the last couple of weeks, weve been constructing temporary frame pieces, which were cutting out of particle board. The reason were doing this, and the process behind what were doing will take a little bit of explaination, so be prepared for a long entry.

The reason were cutting these temporary frame pieces is so that were sure the hull is straight. If you look at the picture, you may notice two pieces of board... one smaller piece of board, sitting on top of the particle board. The smaller piece is the actual frame piece that will be in the boat when its put on the water. The hull goes much farther up than this though, so we are using temporary pieces during the hull setting process. Once the hull is set, we will remove the temporary pieces and install the permanent pieces, so that we can add the deck.

In order to cut these sacrificial particle board frame pieces, we started with a 4x8 piece of particle board. We set the actual frame piece on the particle board and clamped it in place. We then determined the center point and line of the actual frame piece and extended this center line through the particle board, so that we could measure needed dimensions. After measuring the center line, we extended the end-lines of the permanent frame piece up the particle board, and measured from the center line to the top corners. In order to make sure our cuts were true, we measured cross-angle. we then added the notches and cut it all out with a power saw, except for the notches, where we used a jigsaw.

Click here to see the video summary of what we did.

Read More..

Mounting Frame Pieces

Mounting Frame Pieces
Originally uploaded by OzzyC.

Weve begun to mount the horizontal (port-to-starboard) frame pieces. There are six in all, and yesterday we mounted three.

We started by temporarily removing the stringers. This was Gregs idea, and I saw no need to keep them mounted, so they were pulled down. Next we measured the distances for all of the frame pieces, relative to the rear transom, and marked these distances on the building frame.

Next, we used the laser level to find the horizontal mounting point. We lined up the laser level with the reference point on the rear transom that we created a few weeks back. Next, we ran a piece of string down the bow-to-stern center line. This way we have the horizontal and vertical points of reference on each frame piece accurately measured. (You may remember that we drew these reference points on the frame pieces when we constructed them.)

Next we screwed 2x4 jigs into the building frame, in preparation for mounting the frame pieces to these same 2x4 jigs.

Next, we set the frame pieces on a floor jack, and lifted the jack to the correct height and center. This allowed us to make fine adjustments and get the frame pieces accurately placed. Once we lined up the horizontal points of reference with the laser level, and the vertical point of reference with the string, we screwed the frame pieces to the 2x4 jigs. This process went very quickly.

NOTE: Once we got the second frame piece mounted, we reset the stringers in place, knowing that it would be difficult to place them later.

Click here to see the video summary of what we did.

Read More..

Mounting the transom to the frame

Transom mounts
Originally uploaded by OzzyC.


Rear Transom Mounted
Originally uploaded by OzzyC.

Last weekend we mounted the rear transom to the working frame. We started by constructing the vertical frame mounts. The vertical frame mounts were built from the bottom up, using 2x4s screwed to the 2x6 frame on the floor, and then screwing the two angle-cut 2x6s to the 2x4s. The angle-cut 2x6s are cut to the same angle as the stringers where they attach to the transom. This is shown in the first picture.

Next, we mounted the rear transom to the angle cut frame piece with screws. When you put the transom on the frame, make sure its level and that the angle cut mounts are placed an equal distance from the center, and in a place that wont interfere with construction.

Read More..

Mounting the Front Transom

Mounting the Front Transom
Originally uploaded by OzzyC.

We hit another milestone by getting the front transom mounted to the jig.

This process needed to be even more precise than the process of mounting the rear transom. With the rear transom, we needed to make sure that we were correct on two axes... think X,Y axis from geometry class. When we mounted the rear transom, we had to make sure our measurements were consistent on both the X and Y axes, or the whole boat would be off.

When we mounted the front transom, we had to make sure that we had correct measurements on all three axes... think X,Y and Z axis from trig classes.

This accomplishment took a lot of thought and planning. We had to make sure the transom was at the correct angle. If the angle was too small, the boat would have a flat front, and woldnt plane correctly. If the angle was too big, the bow of the boat would be too low, potentially allowing water to come over the bow. In order to accomplish this, we cut pieces of 2x6 to the correct angle, and screwed these pieces into the transom. We then screwed sections of 2x4 onto these 2x6s. The 2x4s would be then screwed into the jig frame on the floor.

In the accompanying picture, you will also see that we screwed a second 2x4-and-2x2 section onto the back of the 2x6 angle pieces, and the 2x2s stick up a little more than 6 inches from the center of the bottom of the front transom. This is because the reference line is 6 inches below the point of the transom. (Remember, were building this upside-down for the moment, so thats why the 2x2s are pointing up.) We used two pieces of 2x2, set in equal positions relative to the center point of the transom, so that we have two points of measurement, to ensure maximum accuracy.

Next, we rough-set the transom onto the jig frame, and clamped it to the jig, so that we could tweak our settings, setting the transom in place permanently with screws. After clamping the transom to the jig frame, we used a level and a tape measure to ensure we had things absolutely accurate. We checked the height using the laser level, making sure the reference points (marked on the 2x2s) were accurate relative to the reference points on the rear transom. We checked the distance from the rear transom by measuring the distance from the front to back on both the left and right sides. We made sure the transoms were centered correctly by measuring from front-left to rear right, and by front-right to rear-left. We knew we were good to go when we verified that these measurements were the same distance.

Read More..

Its starting to look like a boat

BoatFrame
Originally uploaded by OzzyC.

This week, we set the rest of the sacrificial frame pieces in place, using the same process described in last weeks entry. This photo shows the full skeleton of the boat, and based on the shape of the skeleton, you should now be able to mentally picture the shape of the hull.

At this point, the stringers and sacrificial frame pieces are not precisely set in their final position, but theyre pretty close. Some of the notches are too wide, too deep (or too shallow), or some combination thereof. But again, its pretty close.

Next week we will do more precise adjustments of the frame by cutting the too-shallow notches a little deeper, and shimming the areas where theres too much slop. That process will likely take a couple of sessions, because were picky on precision.

Read More..

Question Comment from a reader

The following is a comment from Squid, a member of the forum at www.bateau.com

The picture Squids referring to is shown earlier in the blog, but you can click here for a direct link to the picture.

---Begin original comment---
[S]hure looks like a flat bottomed boat at the transome end. How do you think it will handle in the chop and wind. I know they have wind in Iowa. I am interested in building this boat but will wait till you have yours done and can tell me how it handles. Squid.
---End original comment---

This is a valid point, and one that I honestly hadnt considered. But even if I had, this boat actually belongs to my friend Greg, so I didnt have much input on which plans were actually purchased. Im just the first mate. (Call me Gilligan.) Now that the point is brought up though, heres my take.

Youre absolutely correct, this is a flat-bottomed boat. The result is that it will probably rock-n-roll a little more in choppy water, but I wouldnt worry about that a whole lot. Its going to be a big, heavy boat, so I suspect that itll take quite a bit to make the boat roll excessively. As far as the wind goes, I dont think itll be a huge factor. The rear transom isnt much different from your standard power boat, so I suspect the amount of surface area that the wind could catch is probably comparable to a standard displacement hull. The front transom is relatively small, so I dont see wind as a factor here either, and the same goes for the sides. Besides, its not like were rowing this big-ass boat. Gregs going to put in a couple of big motors to do the work for us.

In short, the only way I see wind being a factor is when the wind causes waves on the water, in which case the boat will probably rock a bit more than a displacement hulled boat.

Read More..