Clipper's Vera Cruise Build

Clipper's Vera Cruise Build

Sunday, March 31, 2013

Gluing Frame Assemblies - Second Attempt

I've worked out the kinks in my glue up process and have started making progress on getting the frames glued up. I'm still taking my time and doing each glue up in stages, and so far the results have been satisfactory.

The basic process is to edge glue two frames parts together first. Let that cure, and then clean up the glue line. Then edge glue the filler block for that joint and let that cure. Clean up the glue line for that and then glue on a gusset. So far I've glued up portions of frame 4, 5, and 6 with 6 being the furthest along. There are faster ways of accomplishing this, but I am not in a hurry and prefer to do it this way.

Here is frame 6 getting reglued. The cinder blocks are a cheap way of getting some weight to hold the parts flat (I bought 6 of them for less than 10 dollars). They are resting on a piece of particle board (MDF) which helps to hold the frame parts flat and protects them from the cinder block. There is wax paper between the frame and the layout board as well as MDF. This keeps the epoxy from gluing the frame to the layout board and MDF. In this first photo the left corner has not been glued up yet but the frame pieces have been nailed to the layout board to prevent movement.

Here is the result of that second glue up. As you can see, the glue joint is much better and the parts are aligned. Once the glue is cleaned up on this surface, a gusset can be glued to it.

These three frames are all assembled with two frame parts making the bottom section so I am able to glue them up separately, I will join them in the middle after finishing up the first side gussets. The two larger parts in the next photo are from frame 5 as these two parts are edge glued.

Then frame 4 parts are edge glued. The filler block for frame 6 has also been glued into position. 

Next step is to glue in the filler blocks for frames 4 and 5. Here is the filler block for frame 4 before gluing.

And here is the frame 5 parts after the filler blocks have been glued in.

The plan is to glue up the gussets for these three frames on one side only. Then I will flip the frames over and glue up the gussets for the other side as well as the floor timbers. The process will be a bit different for the second side because the gussets on the first side raise the overall assembly off the ground. So it will be necessary to support the frames with scrap plywood when I get to that stage.

The final picture shows the frame 5 parts after the gussets have been glued on. The glue has not been cleaned up yet. In addition to gluing the gussets, they are attached with bronze boat nails. Boat nails are nails that have ridges on the shank of the nail. The intention of the ridges is to hold the nails in place after they are hammered into the wood.

The process of gluing up the gussets is a bit more complicated than edge gluing. I read in the Glen L builder's forum that some people have had problems with glue joints being starved of glue after the curing process. The suggestion made in the forum is to do the glue up in two steps.

First apply the epoxy resin to the gluing surfaces before adding any filler material to thicken it up. A chip brush works fine for this. Then thicken up the resin and apply the thickened resin to the same gluing surfaces. The initial coating of unthickened resin will soak into the wood and keep it "wet" until the second thickened layer can cure.

Then, the boat nails need to be added to the assembly while the glue is still curing. It is best to pilot drill each hole with a drill bit a smaller than the nail shank diameter. This helps prevent the nail from splitting the wood as it is driven home. The gussets will want to move around as you are driving the first nails so I would drive a couple part of the way in, just enough to prevent movement. I would make sure that the gusset was in the correct position as I did this. Once those initial nails are partly in, I would pilot drill the remaining holes and add the remaining nails Afterwards, everything is cleaned up to get most of the excess epoxy off the parts. Finally the part is covered with wax paper and the cinder blocks are placed on top to hold the part flat until the resin cures. I usually let the parts cure a minimum of 8 hours before removing the cinder blocks.

For those unfamiliar with epoxy resin, I will give a brief explanation of the process I use for preparing the resin. This Marine grade epoxy resin was purchased from Glen L Marine and included a bag of white silica beads. These are very tiny beads that are used for thickening the resin. You don't want to breath these, so best to wear a respirator or dust mask.

The resin is mixed 5 parts of resin to 1 part of hardener. This can be done by volume or by weight. I prefer to do this by weight as it is more accurate. I bought a digital scale from Harbor Freight Tools just for this purpose.

The scale has a button to tare the scale. This means that you can put something on the scale and then zero it out. This way, it is easier to add the exact amount of weight of what you need. So I first place a plastic cup on the scale and reset it to zero. The I add the desired amount of resin. I have been typically working with 1 ounce at a time, (sometimes 2 ounces). The scale is then reset to zero again and one fifth (or 0.2 ounces in this example) of hardener is added. Then I use a wooden stir stick (popsicle sticks or tongue depressors) to stir the mixture for a minimum of a minute.

The last step is to add a small amount of silica to thicken the resin. This should be done after mixing. You need to add this in small amounts because it doesn't take much to thicken up the resin. Depending upon the application, I generally try to get it the consistency of warm peanut butter, (maybe even a bit less thick). This is mixed up and then it's ready to apply to the parts. The parts should be cleaned beforehand. I use denatured alcohol to do this.

One final note. Epoxy resin is nasty stuff and you don't want to get it on your skin. So wear protective gloves. I won't go into all the safety issues here, but suffice to say, it is best to read up on this before attempting this for the first time.

Until next time..............

Friday, March 29, 2013

Experiments In Cabin Height Increases

As I have been building the boat, I have sometimes lamented on the fact that this boat has a low cabin height of 5'4" which is seriously short for me at 6'. I felt it was something I would have to live with because I was sure that raising the cabin height would look all wrong with the boat.

Today, after discussing space increases with a fellow boat builder, I decided to try and see what might be done. At this point the whole thing is an exercise and not a firm plan. Mainly I wanted to see if it would be possible to increase the cabin height without destroying the lines of the boat.

I first considered raising the deck along with the and keeping the cabin height the same. This came out of the discussion with the other builder. He has some good ideas which I wanted to see if they might be practical for my boat. I didn't have a lot of luck with this approach, primarily because I have gotten to the point in my construction where making deck height changes would be a fairly substantial step backwards. I'm not particularly prepared to go that far so I set that idea aside for now until I can get more feedback.

As a second way of tackling cabin height, I decided to try increasing the cabin height itself and leave the deck height the same. At first this looked hopeless. Everything I tried looked wrong. But I stuck with it and keep tweaking the shapes. After awhile I came up with a design which gives approximately 8 inches more of head room and still retains the look of the 50's styling that I wanted. Remember, the deck height is the same, only the cabin has been increased in height and the wing shape has been changed slightly.

Now the following pictures are only drawings and if I was to pursue this, it would take some engineering of the existing design to make it work. But the beauty of the boat is that the cabin is essentially just a box with two wings trailing back towards the transom. The wings are what make it possible to get the extra height and  still look right. That and a little creative coloring to give the illusion of sleekness. So here are the before and after pictures.

Sunday, March 24, 2013

First Attempt at Frame Glue Up - Fail

Well, the first try at gluing up a frame ended in failure. The mistake I made was trying to glue too many parts at the same time in order to avoid wasting resin. In this case the amount of resin was fairly small so the end result made the effort to save resin even more troublesome.

So the event went like this. Frame 6 was going to be my first attempt to glue up. Readers will recall that each frame joint consists of the main frame parts, a filler block , and two gussets. I didn't want to try and glue all of this together at the same time because there were two many parts to control and clamp. My thinking was that I would edge glue the two main frame parts and the filler block together, let that epoxy cure, clean it up, and then glue one of the gussets  over that joint. I figured that the amount of epoxy needed for the edge gluing was smaller than the minimum amount I could measure and mix, so to save resin, I would edge glue both frame joints at the same time.

I knew that I would need to clamp the filler block in position to keep it from moving. And I assumed I could keep the frame parts from moving by using nails through them into the layup board. I intended to add a cinder block on top of this to hold everything flat. I would use the same approach on the other end of the frame.Here is the setup I came up with.

I proceeded to mix up the resin and apply it to the edges of the first joint and nailed the frame parts into position. Then I applied resin to the edges of the filler block and put it into position.I took a clamp and lightly clamped the filler block into position, just enough to hold it there.

I performed the same operation on the second joint. Then laid wax paper over each joint, a small board over the wax paper, and then a cinder block over each joint to hold it flat. Finally I slightly tightened up the clamps (mainly because they felt loose to me). Little did I know that the clamping forced the filler block (which you'll notice is wedge shaped) to move the frame parts slightly. I left everything to cure until this morning.

This is what I found.

See how the filler block forced the edges out of alignment on both corners of the frame assembly. You'll also notice that there is a sizable gap in the first photo. Finally, there was glue that ran over the edge of the parts to fill in gaps in height. This is because I glued up both ends of the frame at the same time and the cinder blocks were not heavy enough individually to force the parts to lie completely flat.

One other result of this movement was that one of the frame parts was forced out of alignment with the layup marks on the layup board. This wasn't immediately apparent to me yesterday because the nail was holding the frame part in position. When I removed the nail, the frame part moved 1/8" off the line. You can see this on the top part in the following picture. That long edge should be right on the line but it is shifted away.

Well, needless to say, I was disappointed in this first attempt. I went through all the normal human emotions: denial, anger, denial, thinking I could live with the mistake, acceptance of the problem, and finally resolve to correct the parts. So I spent some time looking over the movement and determined that careful cutting apart of the frame joints should yield repairable frame components. Worst case, I thought, would be that I would have to remake these parts. This was why I originally chose frame 6, because it was the smallest of the frames, and therefore the easiest to remake if needed.

Anyway I cut the parts apart at certain joints and left other's intact. I then cleaned up all the glue and slightly ragged edges (from cutting). Here are the parts after that operation. The filler block is still attached to the top part, it was okay.

The plan for the next attempt is to do one side at a time, use two cinder blocks for weight, and not use the clamp on the filler block. The parts to be glued up first are the top two parts in the previous photo. There is no need for the clamp because the filler block is still attached. I will glue this up and let it cure.

Then I plan on edge gluing the other frame side piece into position without the filler block. Once that's cured, only then I will glue the second filler block in place. At that point, I can safely use the clamp to hold the second filler block in position.

So in the next blog article, I will let you know how it came out. But the lesson learned here is to not try and glue more than two parts together in the same assembly at the same time. Ad double check all assembly after it's together to make sure everything is still okay.

Until next time, cheers.

Wednesday, March 20, 2013

Evaluating Building Form Designs - Updated

As I move forward, I need to build the building form. The building form is a framework upon which the boat will be constructed. It holds the frames in position while the longitudinal members (keel, battens, etc) are added. This form needs to be accurate, sturdy, and rigid.

Furthermore, because of the constraints with my work area size, the form needs to be movable. This is so I will have room to work around the boat while under construction.  It also has to allow for the 4" rise of the floor at the back of the garage. And I want it to allow me access to the underside of the hull while under construction. So it needs to be tall enough to do this. However, it's not simply a matter of making it taller.

I will eventually have to move the boat out of the garage and flip it over. This means that I will need to have some temporary structure above the keel to take the load of the boat as it flips over. All this and still get through a garage door opening that is only 80 inches high.

So I have spent a fair amount of time mulling this over and I've gone through four design versions of the form (on paper) trying to figure this out. Here is version 3. Forgive the crudity of the drawing. This version assumed that I would build the boat with the aft end at the back of the garage. The shorter legs would compensate for the rise in the floor. (The scale is way off!!!!)

There are several disadvantages to this design. The shorter legs mean that when I roll the form out of the garage to gain working room at the transom end, I would have to add temporary longer legs to support the boat. Because my driveway is tilted, the long horizontal piece on the right side would be hanging out in the air when the form is moved out. Again, I would have to add some support under this temporarily. And the form is more complicated because of the difference in leg heights. Finally, clearance of the sides was impractical because of the width at the back of the boat.

For version 4, I decided to see what would happen if I were to build the boat with the bow at the back end of the garage.

 This version places the long horizontal piece on the right above the rise in the floor. All of the legs would be on the lower floor so there is no need to make some of them shorter. Because the bow is narrower than the stern, I will have much more clearance on the sides. This means that I will not have to move the form out of the garage as far in order to work on the bow end. Barring any other things I haven't thought of , I believe this is the version I will be building. The drawing doesn't show it, but it will be suitably braced so that it is quite rigid. There will also be locking casters mounted to the legs so the form can be moved.

Here is what the form looks like in the plan.

And here is a poor quality photo that gives some idea of what the form is actually used for. Notice the frames that have been mounted to the form.

So I need to probably sped a bit more time thinking about this and then compile a materials list for the wood and hardware to build the form.

Until next time........

Update 3/21/2013

I did a bit more thinking and ended up with version 5. A bit more rigid and the rolling portion is better designed. Pictures will be coming in the future as I begin construction. Still have to buy the materials.

Sunday, March 17, 2013

Evaluating The Building Area

So this last week I was on vacation and I was supposed to spend a chunk of that time building the boat. Alas, it was not to be, as several events occurred which conspired to steal my time. I did get the frame parts finish sanded and I've purchased all the supplies and tools I need to assemble the frames.

However, I was able to spend some time thinking about the garage where I will be building the boat. To start, the assembly  requires a building form to attach the frames to in order to set the length and shape of the boat.. This form will be nearly the same length as the boat so I had to determine how it was going to be placed in the garage.

The form needs to be either anchored to the floor or if movable, then a means of preventing it from moving needs to be devised. The boat is 21 feet long and 8 feet wide. My garage is 21 feet and 5 inches deep and approximately 12 feet wide in the area where the boat will be placed. Furthermore, the floor is stepped at the back of the garage for approximately 4 feet with the step being approximately three and one half inches higher than the remainder of the garage floor.

Here's the rub. In order to provide enough room for myself to work on the boat, I will need to make the building form movable  This will allow me to slide the form sideways when I need to access the side nearest the garage wall. I have enough room to move it 3 feet from the wall, normally it will be 1 foot from the wall. For the length, I am okay except when I need to work on the back of the boat. It will then need to be slide the form out of the garage approximately 3 feet.

What this all means is that the form will need to have wheels and some form of locking mechanism to keep it in place. Furthermore, since the aft end of the form will be on the stepped portion of the garage floor, I will need to have some way to support that end when I slide it out of the garage. Otherwise the rear legs and wheels will be dangling above the floor by 3 inches - not good.

Your probably thinking I'm crazy about this time, but I've worked all the details out and I believe I can make this work. It will be tight and a pain at times but I knew this when I decided on the Vera Cruise design. Why didn't I choose a smaller boat? Well frankly, I did consider that early on in the process but I just fell in love with the design I choose so I decided to make it work.

I'm working on some final details for the building form before buying the lumber I need to build that. Between the building form and assembling the frames, I have enough work to keep me busy for the next month so future updates will be covering these processes.

Until next time...........

Sunday, March 10, 2013

Initial Frame Fitting - Part 2

In the previous article I showed how I fit the frame parts together. I neglected to show what the end result of the two parts looked like. Here is that photo.

The remaining steps of fitting the frames involves making the gussets. Remember, these are plywood reinforcements that cover the seams between the side and bottom frame members. On my boat, these must extend 6 inches onto each frame member. So I measure up from the bottom piece the required distance and draw a line for reference. The same is done for the bottom frame member.

Next, using poster board I create a template that matches the contours of the bottom and side frame members and extends to the previously drawn reference lines. A little bit of cutting and drawing and eventually you end up with a trapezoidal shape representing the final shape of the gusset.

The gusset should extend diagonally across from the inside edges of the frame parts to form a diagonal brace. Transfer the template outlines to the appropriate thickness plywood and cut them out and sand to final shape.

This diagonal brace on the gusset will leave an area on the inside of the frames where there is no wood. The gussets will be attached to both sides of the frame (generally), so this open space between the gussets should be filled with a filler block for added strength. I’ve heard that these filler blocks are not absolutely necessary in some cases, but I think the added strength and better appearance is worth the extra effort.

The filler blocks are a trial and error process. You start with a board the same thickness as the frame parts and large enough to fill the area that is open between the gussets. One edge needs to be straight. This can be done on the belt sander. Lay this edge against the inner edge of one of the frame parts (side or bottom doesn't matter). Mark and trim the wood so that it matches the second inner edge of the frame. Make sure the filler block will be large enough to fill the entire open area under the gusset. Lay one of the gussets over this area in its final position and draw a line for the diagonal. Cut and sand this line and adjust as necessary until the part fits correctly.

The part will be some form of triangle after this is completed. It should be the same size as the open area between the gussets. When the gussets and filler blocks are latter glued to the frame parts, they will form a nice solid and strong connection at the frame joints.

You should mark all the parts with identification so you know where they go later during final assembly. I simply identify the frame number, the part type (gusset, filler block, etc) , and which side of the frame they go on. Ideally the parts are symmetrical and it doesn't matter which side they go on, but this isn't a perfect world so better to keep their locations correct.

The final step in this process is to add a brace across the open end of the frame. When the frames are mounted to the building form, they will undergo quite a bit of force as other parts are added to the structure. The brace insures that the frame doesn't get forced out of the correct shape during this process. The brace will be removed later once the boat has been turned over.

So those are the steps that I use to initially fit the frame parts together. With some variations, this is the same process I used for all six frames. 

This coming week I will be finish sanding all the frame parts, filler blocks, and gussets. The reason for this is because all of these parts will be coated with epoxy resin after final assembly. This is to protect against moisture. Finish sanding them beforehand ensures that they will have a relatively smooth finish after the resin is applied. It also makes applying the resin easier.

Take care and I hope this article will be useful to someone in the future.

Thursday, March 7, 2013

Initial Frame Fitting - Part 1

So I have talked in the past about initially fitting frame parts and I have shown some end result pictures but never really explained the process I use. This article will go through the steps I take to fit the frame parts together. The article is actually in two parts because I wanted to post an update and I haven't completed all the steps and taken all the photos for this article. I will be too busy over the next few days to do that and I did not want to delay posting another blog entry.

It should be noted that there are any number of different ways of accomplishing this process. This is the process I am using. I make no claims that it is the best or the only way to do this. Given my constraints on spending, I elected to fit these parts in the fashion I will describe.

When the parts are first laid out, the side pieces are a bit longer than they need to be. Additionally, parts such as gussets and gusset filler blocks are not drawn on the plans. There are only general instructions about how much of the frame parts must be covered by the gussets. All of these pieces will need to be final fitted or created.

The end result will look like this

The first step is to align the bottom frame piece to the chine and keel points that were previously measured and laid out on the layout board. 

These measurements come from the plans and indicate where the centerline of the bottom frame reaches at the keel and were the ends of the frame meet at the chine blocks. See the article that explains these terms here: Article with chine, keel, and sheer description

The frame bottom needs to be temporarily attached to the layout board so that it doesn't move. This is done with nails. The holes for the nails should be pre-drilled slightly smaller than the nail. Predrilling insures that the wood doesn't split when the nails are hammered in.

Next the side pieces are aligned to the sheer point at the top and to the curve line representing the outer edge. The sheer point and curve were also previously drawn on the layout board.

At this point, the side pieces are too long and overlap the bottom frame member. 

After the side part is aligned to its marks and the curve, a couple of marks are made on both edges to show where the part needs to be trimmed. These marks are then transferred to the side of the part. This will be where the part is cut. Always double check the part again to make sure the line is in the correct location.

I don’t have a band saw so I use a jig saw to make the cuts instead. However, that requires that I cut a bit further away from the line than I might do with a band saw. Either way, it’s best to not cut right to the line. Better to leave a bit of excess and then sand down to the line using a belt (or disc) sander.

The next article will detail the remaining fitting steps as well as making gussets and filler blocks.