CAL20 Cradle data request

Greets: Was wondering is any CAL-20 owners who use a solid cradle for there boat could send me some data on the solid cross members, as I need to build a cradle for the boat. A base steel cradle I have but I dont have a pattern for the cross members nor the distance measurement between the two horizontal members. I'd rather build one of these as opposed to using one with four pads as its easier to work on the hull. One that works similar to pic attached. Issue is I dont have access to the boat for another month so need to work from drawings, templates or measurements. If anyone has any data it would be greatly appreciated. -- /ch

Chris h wrote: > > Greets: > > Was wondering is any CAL-20 owners who use a solid cradle for there > boat could > send me some data on the solid cross members, as I need to build a cradle > for the boat. A base steel cradle I have but I dont have a pattern for > the > cross members nor the distance measurement between the two horizontal > members. I'd rather build one of these as opposed to using one with > four pads > as its easier to work on the hull. > Mine sits on a trailer with athwartships supports--basically, transverse bulkheads cut to the shape of the hull. A prior owner did the work. This is really easy to do with a "tick stick." You would place a big rectangle of cardboard or plywood athwartships under the boat, wide enough to accommodate the shape you want, which is the hull shape at that location. The boat and pattern material should be level, or at least, the pattern material should be level with the boat's waterline.You take a stick, a piece of wood with a point cut onto one end. You hold it with the point against the hull and trace the shape of the rest of the stick on the pattern material. Then you move it along the hull a little bit and do it again. And again. And again. And so on. Then you take the pattern material, place it on the plywood that you'll cut your support from, and hold the stick in position one, and make a mark at the pointed end on your plywood. Do it for each marked position of the stick. You'll end up with a series of dots on your plywood. Then use a flexible batten and connect the dots. You will have the shape of your hull at the point where you measured it. You can probably google "tick stick" and find an illustrated explanation. _It's really easy._ I've made cradle-support patterns this way quickly & accurately. You'll use the technique often around boats, especially on the interior, because boats are just not rectilinear. Chris Campbell > > >

--- In Ca… [at] yahoogroups.com, Chris Campbell <clcampbell@...> wrote: > > Chris h wrote: > > > > Greets: > > > > Was wondering is any CAL-20 owners who use a solid cradle for there > > boat could > > send me some data on the solid cross members, as I need to build a cradle > > for the boat. A base steel cradle I have but I dont have a pattern for > > the > > cross members nor the distance measurement between the two horizontal > > members. I'd rather build one of these as opposed to using one with > > four pads > > as its easier to work on the hull. > > > > > > > > > > > > > > Mine sits on a trailer with athwartships supports--basically, transverse > bulkheads cut to the shape of the hull. A prior owner did the work. > > This is really easy to do with a "tick stick." snipped You'll use the technique often around boats, especially on > the interior, because boats are just not rectilinear. > > Chris Campbell Some of them are not even symmetrical. My Choate 40 was 8 inches wider at the deck just at the mast on one side than the other. Dennis Choate had built it with the mold from the Scott Kaufman design but, because he wanted to modify it for Transpac, he had sprung the mold out for greater beam and a flatter entry. In doing so, it got a little asymmetrical. I think Dennis was building the hull for himself, then a customer came along who wanted a bigger boat and wanted Dennis to go with him. I came along about that point and bought it. I had been looking for a smaller boat but he said he would sell me this one for the same price. It was a rocket off the wind but suffered a bit upwind in a chop compared to the sister ships. We had a pretty good class for a while but nobody races them anymore. It was the same length as a Cal 40 but had a 13 foot beam and the beam went almost all the way aft. I'm sure some other mold-built boats could be a bit asymmetrical so you should check the entire hull, not just one half. Mike Kennedy Conquest Cal 40 # 96 > > > > > > >

On Wednesday 25 March 2009 16:43:59 Chris Campbell wrote: > Mine sits on a trailer with athwartships supports--basically, transverse > bulkheads cut to the shape of the hull. A prior owner did the work. Thats exactly what I want to build. Problem is boat is at the MMA yard and Im in Ottawa....:) Need to build cradle prior too picking up boat so can transfer boat from trailer to cradle at arrival point. -- /ch

mtkennedy1 wrote: > > > I'm sure some other mold-built boats could be a bit asymmetrical so > you should check the entire hull, not just one half. > The great virtue of the tick-stick method is that it simply reproduces what you have, especially if you use enough points. You're right that we should never assume that we can make a half shape and double it. Errors do creep in in design and production. Sometimes we're better off not even knowing about them, because once we know, that's all we can see. It's like that one big piece of debris that is in the fresh varnish. Chris Campbell > > > . > >

Chris h wrote: > > On Wednesday 25 March 2009 16:43:59 Chris Campbell wrote: > > > Mine sits on a trailer with athwartships supports--basically, transverse > > bulkheads cut to the shape of the hull. A prior owner did the work. > > Thats exactly what I want to build. Problem is boat is at the MMA yard > and Im > in Ottawa....:) Need to build cradle prior too picking up boat so can > transfer boat from trailer to cradle at arrival point. > Here's what you do: have the yard's travellift hold the boat just over your new cradle, wiuth the cradle in the right fore-and-aft position. Place a sheet of cardboard the same shape as the plywood you'll use for support material under the boat, in the place where the plywood will be attached to the cradle. Do the tick-stick thing, then immediately transfer the shape to the plywood and cut it out with a saber saw or Sawzall. You'll need one forward and one aft. It won't take long. Just for acccuracy sake, make sure that one tick mark on each side of the boat is at the waterline, even if your plywood will not reach up that far. This lets you orient the plywood before you make the rest of the tick marks so it's level with the boat's waterline. There's not a lot of shape in the Cal 20 underwater hull where you'll probably be supporting it. It's not going to be complex. Here's a link to one site showing use of a tick stick. This one looks like somebody was doing a boat interior bulkhead: http://www.shortypen.com/essays/tickstik/ I prefer to either outline the bottom of the stick, or draw a line along one side (notch the side so you match the right side to the line when reproducing the shape). There are other links by searching "tick stick" in google. One good one had a site address that was too long to fit in this reply (it was one "word" and there was no break). Please note that nobody can give you a pattern from their cradle or trailer because your cradle may put the supports in a different fore-and-aft location, where the hull's shape will differ. I repeat: _this is really easy._ It's harder to describe than to do. If you want to work at it in leisurely fashion, have the yard hang the boat over your cradle at the end of the day, then you can work into the evening and have it ready to drop the next morning. Chris Campbell > > > >

On Thursday 26 March 2009 09:39:05 Chris Campbell wrote: Sounds like what we are going to have to do. If you could send me one measurement that would be helpfull to get things aligned to simply drop in the boards once they are cut. What is the distance between the front and rear crossmembers on your cradle? As this will involve some welding to get the braces in place as well as the frame for the crossmembers this dimension would be very helpfull. Best regards and thanks. -- /ch

Chris h wrote: > > > > Sounds like what we are going to have to do. If you could send me one > measurement that would be helpfull to get things aligned to simply > drop in > the boards once they are cut. What is the distance between the front > and rear > crossmembers on your cradle? As this will involve some welding to get the > braces in place as well as the frame for the crossmembers this dimension > would be very helpfull. > It will take a couple days, as I have the misfortune of being obliged to work for a living (after examining retirement account statements, projected work life ahead is about 40 years) and have an obligation to help train new schooner crew (on-shore training) tonight. The boat's on a trailer out at the storage yard. I can probably send you a picture of the boat on the trailer this evening; the camera with the pix is at home. It's very non-critical, since most of the weight is the keel bulb and feel fin, and the boat really sits on the keel (make sure your cradle has ample support under the keel!). My trailer's bunks or beds or whatever for the boat are not quite properly arranged for height--they're a bit low, and the boat sits on the keel and rocks for-and-aft on it until I drive some shims in. Chris Campbell > > > >

On Thursday 26 March 2009 10:46:05 Chris Campbell wrote: > It will take a couple days, as I have the misfortune of being obliged to > work for a living (after examining retirement account statements, > projected work life ahead is about 40 years) I completely understand. Also realized as i hit the send button that I do have a line drawing in my cal 20 data folder on the system somewhere. I can just take the distance offsets from that as its a scaled drawing from the manual. So no need to go to any effort please.. > I can probably send you a picture of > the boat on the trailer this evening; the camera with the pix is at > home. It's very non-critical, since most of the weight is the keel bulb > and feel fin, and the boat really sits on the keel (make sure your > cradle has ample support under the keel!). A picture would be great. That combined with the line drawing should get me to the 90 percentile level. The rest we can do at the marina as you suggest. > My trailer's bunks or beds or whatever for the boat are not quite > properly arranged for height--they're a bit low, and the boat sits on > the keel and rocks for-and-aft on it until I drive some shims in. Better a bit low then too high..:) Shims are wonderfull things to have handy. Best regards and thanks, Got this last issue sorted now. Feels good. Thanks for your help. /ch