Jim Michalak's Boat Designs
118 E Randall, Lebanon, IL 62254
A page of boat designs and essays.
(1mar00) This issue presents two more Piccup spinoffs, Mixer and Mixer2. Next issue, 15mar00, will repeat the lecture on taping seams.
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The original Piccup Pram with small sail.
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MORE PICCUP SPINOFFS
Here are two more spinoffs of my boat Piccup Pram which is shown up in the title box. To review Piccup is 11' long and 4' wide, sort of wide and fat with capacity to take two normal adults. It is a taped seam hull with a multichined cross section. In the 15jan00 issue of this page I presented two spinoffs of the design, Piccup Squared and Twixt, both prams with layouts similar to Piccup but with simpler flat bottoms. The two spinoffs presented this issue have Piccup's multichine cross section but pointy bows in lieu of Piccup's wide pram bow. These two boats, Mixer and Mixer2, are not currently in my paper catalog but plans are still available for $20 each if you are interested.
I think I should say that these little boats all weigh around 100 pounds if built per the blueprints and are intended for the cartop. Once you decide to trailer a boat you should think hard about building instead a 15' boat which will have a lot more room and capacity, speed and seakeeping, and yet can still be handled solo.
MIXER
Here are the lines for Mixer. She is 12' long, a foot longer than Piccup, and 3'9" wide, just a bit narrower than Piccup. The interior layout, with a 6-1/2' long open cockpit between buoyancy/storage boxes, is the same as Piccup's. (It bears repeating that these end boxes save your butt in a capsize by floating the hull high and level. Any boat without them or something equal will swamp hopelessly in a capsize. If you make the hatch openings really large you also run the risk of hopeless swamping in a capsize. Piccup as drawn will float on its side with its hatches well clear of the water.)
By the time I drew Mixer I had already a year's experience with my Roar rowboat which has essentially the same shape. I though the original Roar, which had this plumb bow, quite fast and good in rough water, more or less the same as a Payson dory in that respect but with a lot more interior room. It has the feel of an "over the water" boat like a scow and not the feel of a "through the water" boat. The stem is well clear of the water as you see. I think it is a very fast shape. What it lacks is tracking ability in a cross wind. A shape like this has very little side resistance on its own. I put a big skeg on my Roar and eventually converted it to a "through the water" bow which holds on a lot better in a cross wind. I should have tried a full length keelson first but was thinking in a different direction at the time. Piccup has a similar multichine shape but the crosswind problem wasn't noticed, I think because the leeboard, even when retracted, has significant skeg action. And Piccup wasn't the sort of boat I would row in rough wind anyway.
Here is a photo of the prototype Mixer built by Dave Boston of Factoryville, Pa. In this photo he is on vacation in Maine. In this photo the leeboard is on the other side of the boat. He has the boat trimmed right with the stem clear.
Here is another photo of the boat with the sail up. The sail here is the 68 square foot sail I advise for use with all of the Piccup spinoffs, although the photo of the Piccup in the title box has the original 55 square foot sail (it's an old photo and I don't use the small sail anymore). You can see the top of the pivoting leeboard in this photo. Dave has his wife along with him here and you can see Mixer can hold two adults. The boat is trimmed well, the stem still clear and the transom not dragging the water. If you are solo you should get your weight forward to the center of the cockpit as I'm doing in the Piccup photo. But it is not all that critical as long as the stem and transom are clear of the water.
Dave has his sail set very well in my opinion, although there appears to be little wind at the time. The sail is hoisted well up the mast with lots of headroom under it. The luff appears to be quite taut which is very important, you can hardly overdo it. He has loops around the mast at the yard and at the boom so that those spars will stay put and not "pump" back and forth is waves.
In my opinion Mixer is probably the fastest of the Piccup family in smooth water, especially under oars. Her lines are a little less lumpy and kinky than Piccup's and has no hard chines to stir up the water as with Piccup Squared and Twixt. She is narrower than Piccup so she may not have that extra bit of stability that makes Piccup so able in higher winds. On the other hand Dave said he had no problem sailing Mixer in white cap conditions.
MIXER2
Eventually I tweaked Mixer to have a "through the water" bow. It's the same change that Roar went through to become Roar2. I called the new boat Mixer2 and here are some lines of it.
The rest of the boat is identical to Mixer although it appears that I fined up the stern a bit too. I suppose that the original Piccup is about 70% sailboat and 30% rowboat, Mixer is about 50/50, and Mixer2 is about 70% rowboat and 30% sailboat. From the Roar experience I would expect Mixer2 will row a hair slower than Mixer in smooth water, but have the advantage everywhere else. It will track straighter in a crosswind and be faster in waves. So there is a bit of a choice.
There was a Mixer2 built by Ray Gallagher of Conifer, Co. He is still learning to sail. Here is his Mixer2 afloat on a mountain pond.
The paper photos show the details better and I can say that Ray did a first class job on the boat! We really don't have a sailing or rowing report.
In this photo you see a child and woman with the boat trimmed stern down. The transom is still mostly clear of the water and I'd bet the boat would go pretty well even trimmed this way.
It's worth looking at the sail a bit and noting that it could be hoisted higher, and I would do that. The sail on Ray's boat is the same small 55 square foot sail as on the original Piccup as shown in the title box photo. I am in the habit when sailing an unreefed balanced lugsail of hoisting it all the way to the top. I guarantee that everything that happens in sailing will conspire to drop it down so you need to start with it all the way up. With these little ones there is no need for a mast head pulley - just run the halyard through a well polished and waxed hole. So here is how I would set one of these. First loosely set up the tack line and the loop that locates the boom to the mast. Then haul the sail up all the way up and cleat off the halyard. (If you haven't loosely set the tack line first then the sail might fly around like a kite.) Then reset the tack line as hard as you can, you can hardly over do it. Usually when you set it up properly this way you will see, with no wind in the sail, a tension fold running from tack to peak in the sail. Usually when the wind fills the sail that fold will disappear and you will get a smooth tight sail.
In these photos of Ray's Mixer2 you can see a tension fold running the other way, from throat to clew. That's not good for sail trim. Probably needs more tension on the tack line. (You could also retension the halyard for the same effect but the tack line is usually easier.) The lack of tension will cause the sail to twist in use, spilling the wind, making the top of the sail area more or less useless.
I'm not picking on Ray. He'll get it right.
NEXT TIME...
I'll repeat the taped seam essay, one of those most requested "How To's".
AF2
AF2, CUDDY SHARPIE, 20' X 5.5', 600 POUNDS EMPTY
AF2 is the ancestor of both the AF3 and the AF4. The prototype was built by Richard Spelling of Sand Springs, Oklahoma.
AF2 is almost 5' longer than AF3, and is 6" wider and deeper. The result is a boat that is a bit more of a cruiser than a day sailer with more headroom in the cabin. I should mention that you can't keep building the cabin higher without getting badly bit after a while. Every time you raise the cabin roof you need to raise the cockpit seats so the skipper can see ahead. Most of us can see over a 3' high cabin if we sit just above the floor. So if you can sit up in the cabin, as you can with AF2, you can steer from the cockpit sitting on a low seat. If you raise the roof to 4' cabin depth, the skipper will need to sit a least 1' above the cockpit floor. On a small boat the crew's weight is so significant to the total that elevating the crew weight will require adding ballast down low to compensate. Total boat weight suddenly goes up. So adding much more cabin depth to AF2 will probably increase the 600 pound empty weight to 800 or 1000 pounds in a quantum jump. And you'd get a totally different boat.
As it is, AF2 is unballasted and paper studies have shown it will probably sail best at about 20 degrees of heel and will probably capsize at about 50 degrees. Once capsized it should float high on its side, as does the similar but smaller AF3, and take on a few gallons of water into its non-draining cockpit. The AF3 rights quickly with crew weight on the leeboard and AF2 should be similar because the cabin provides buoyancy up high, but lots of boats the size of AF2 won't right that way, the Lightening, Flying Scott and Hobie 16 coming to mind. So there is really nothing sure about self rescue in an unballasted boat, especially in the bad conditions that cause capsize in the first place. One other thing is for sure: once he rights the boat the skipper will need a step or rope of sorts to get back into the boat.
AF2's sail rig is a 114 square foot gaff chosen to avoid a really tall mast. I think it looks pretty traditional too. There is more of a learning curve involved with the gaff than with the sharpie sprit and it takes longer to rig. Richard is experimenting with a polytarp sail, although it's not clear yet if polytarp is suitable for a boat of this weight.
The boat uses simple nail and glue construction with no jigs or lofting. You can see some interesting assembly photos at Rich's site. The plywood bill looks like six sheets of 1/4", seven sheets of 3/8", and one sheet of 1/2". One might think that AF2 is just a notch larger than AF3 but you see she needs about twice the material and labor.
Plans for AF2 are $35.
Prototype News
Some of you may know that in addition to the one buck catalog which now contains 20 "done" boats, I offer another catalog of 20 unbuilt prototypes. The buck catalog has on its last page a list and brief description of the boats currently in the Catalog of Prototypes. That catalog also contains some articles that I wrote for Messing About In Boats and Boatbuilder magazines. The Catalog of Prototypes costs $3. The both together amount to 50 pages for $4, an offer you may have seen in Woodenboat ads. Payment must be in US funds. The banks here won't accept anything else. (I've got a little stash of foreign currency that I can admire but not spend.) I'm way too small for credit cards.
Here are the prototypes abuilding that I know of:
Jonsboat: Greg Rinaca near Houston sent this photo of his completed Jonsboat, land bound until he rounds up a motor.
We also have the start of a Jon Jr, a 12' x 3' personal sized jonboat, down in Texas. Here it is at the beginning and you sort of use your imagination to "connect the dots" to see the boat.
Mayfly12: A Mayfly12 is going together up in Minnesota. The decks are on and he's into the sailing bits. By the way, the sailing bits on almost any sailboat large or small consume about half of the effort in labor and materials. Just when you thought you were about finished! Here is a construction photo from last summer.
Robote: Robote is supposed to be a fast somewhat extreme rowing boat based on my old WeeVee design, thus it has a deep V bottom but is stretched out to 14' long with a very pointy bow. It was drawn as a custom job but if it works out I'll put it in the catalog. The builder has the boat taped together and hopes for trials by April.
AN INDEX OF PAST ISSUES
Herb builds AF3 (archived copy)
Hullforms Download (archived copy)
Plyboats Demo Download (archived copy)