Com-Pac Yacht Owners Association

I am getting ready to make a rectangular bimini top for my Compac 16.
I am looking for some measurements and suggestions  from those of you that have done a similar project.
Much thanks in advance.

This is a follow up to my post on making a bimini . Some time ago, I read about the author of Trailerable Sailing making one with no metal frame. Probably pvc.
Looking for the best way to support the cross bars fore and aft. I tried attaching a cross piece of pvc  to the shrouds, but it wants to slide down.

Mandolin:
   Great idea with the pvc. Gives me some ideas for a low budget bimini for my 23 using either a tarp or some old boat cover material I have lying around. Keep us posted on your project, Thanks
Bob23

Hey Mandolinut,
Couple of thoughts...If you look at the pic Wolverine used to illustrate his thread "installing a round cover", a couple of posts down, you'll see the home made bimini on my boat...I don't have the dimensions but if that design interests you I will be happy to get them and post them to you in a couple of weeks when I get back to Galveston.

The option you described probably provides more shade and may be the one Bob Burgess designed and used in his book "Handbook of Trailer Sailing". It is described in detail beginning on page 173. If you don't have a copy of the book I'll be glad to post the details on that as well if you need them. Mr Burgess started with bamboo cross bars, then used PVC and ended up with 1" dia thin wall aluminum tubing. I believe you can keep the ties from sliding down the stays by installing pieces of small diameter CPVC cut to the appropriate length on the side stays. 

Either of these designs can be used while sailing. Let me know if you need additional info,
Bob H

Could use these fiberglass folding tent poles that just about bend 180 without shattering. But you'll need to anchor them on deck some where, or hang them off the life lines. Clamp them to the life line stanchions? Or...??

skip.

To Bob, The Burgess system is the one I remember. I could not recall the author's name or the book's name.  I liked the idea that it had a great deal of coverage and that it stowed away easilly and very compac.
Your idea about cpvc around the lower shrouds is a good one to keep the foreward crossbar from slipping down. I am invisioning the rear crossbar being supported by two legs, and having two lines coming off on either side of the crossbar  tied off on the two cleats aft. This I believe will stabilize the entire canopy and make it taut. May need to add a few "T's" in the middle of the crossbars to run another piece of pvc fore and aft to prevent sag. This is where I was in hopes that somebody that has made a similar set up could suggest what works and what does not work.
I really like the look of your bimini. Very professional. I have a brother-in-law that is an electrician and could bend the pipe for me. Would have to find a source for the deck hardware.
I will look for the Burgess book at our lacal library now that I know the book and author. Much thanks.

I built one using the book mentioned and it worked great. I paid about $75 for materials about 10 years ago, which consist of white marine vinyl material ( Weblon), 4 - 3/4" alum. tubes and 8 nylon bimini top fittings.
The top is cut to the inside width of the cockpit and the length is about 2 ' shorter then the length of the open cockpit. A cuff is sewn into the front and rear of the top for the tubes. The front tube slides into the front cuff and is tied off at the ends to the side shrouds. The angle of the stays prevent it from falling. The other tube fits into the rear cuff and is held by shorter ( vertical )  alum. tubes on an angle to mid outside coaming, where it mounts. The nylon fittings secure the  tubes and let them fold for storage. Two lines come off the rear tube ends and tie on an angle to the rear cleats to tension the top. (Holes are drilled in the tube ends for the ties) Plastic tips fit over the pipe ends.  
This top can be used while sailing, allows one to stand at the helm, and allows the boom to swing with clearance for the main sheet. The best part is that it rolls up for storage on the bunks below and sets up in a few minutes.

Finished top 70" x 56" ( allow extra length for the cuffs) A canvas shop should sell the vinyl material and sew cuffs.
Front/rear tubes: 62" each   Side tubes 32" each Aluminum tubing from Hardware dept.  3/4" OD
Bimini fittings; 4 External eye ends, 2 Jaw slides and 2 Bimini mounts, Nylon 3/4" ( West marine)
It helps to step mast and set up boom with mainsail hoisted and adjust top to just clear your head while sitting , before drilling mounting holes in outside coaming.
 
Picture: http://s1061.photobucket.com/albums/t479/ke2ee/

Mike

I really like this sun shade on this CP-19 MK1 with it's smooth curve. I think those fiberglass folding tent poles would do just fine. The ends may be in a deck socket or better yet clamped onto the life lines.

It's on the cover of Robert F. Burgess's book Handbook of Trailer Sailing. Be sure to pick up a copy for yourself. $11.95 ISBN 0-396-08303-X The Putnam Publishing Group.

Looks like a bunch of us want to make DIY Bimini's.  Have been thinking long and hard about this as well, read several ideas and still haven't settled 100% on the design but am close.
I like the Bob Burgess design but I want maximum headroom near the beam like Mikeg's and others.  It would be for a CP19 as shown in the picture of Bob B's boat.

Here is Mikeg's bimini for reference.

(http://i1061.photobucket.com/albums/t479/ke2ee/Bimini.jpg)

Basically all I want is one that can be used while under sail, easy to install/remove/stow, not huge so it's less in the way, doesn't interfere with sheets, cheap but not poor quality. The permanently mounted, heavy traditional type doesn't appeal to me as often we won't want to deal with it in the way. I'll make a stow bag for it as well.

I'm still considering pro's and cons of meshed weave vs. sunbrella or vinyl.  Meshed fabric lets air through to reduce windage, wear at seams and movement in stronger winds as air will pass through. The mesh lets you see the sail trim and is cheaper than sunbrella.   Not that you need much fabric.  Meshed is not water resistant at all, does let some light through (95% is good enough for me).   Shade grades are around 60-95% shade depending on which fabric you choose.    Vinyl is out for me, too hot underneath vinyl and tough to sew, may as well match the rest of the sunbrella if I can.

Thinking about see-through yet still good shade mesh with Sunbrella trim for extra stiffening and to make it look and feel a little better along seams, 1/8" shock cord for the aft tie offs and 3/4" round alum poles but with internal pole bungies to collapse like tent poles, quick detach pins for angled "leg" poles.

Also toying with making a full cockpit enclosure for at anchor.  Maybe roll down no-see-um netting, roll down storm flaps with windows in all directions. Full support for maximum tent area and little chance of water getting in.  I made a full sized at anchor awning (fom mast to backstay-just for shade, would still get drenched in rain)  and some other canvas work so so have built up some sewing skills to get this a shot.
Definitely planning on camping out more on this year and next.

Salty19, Thanks for posting the picture of my top and boat , I just left the link to photobucket. I understand you are thinking of different fabrics- good idea, I choose the white marine vinyl because of its construction. The product " WEBLON" is made of a sandwich with white on top to reflect the light,
a middle mesh layer for strength and a light blue or denim like grey fabric underneath to break up the reflected light from the water and stay cooler. I built the same top years earlier when I had another CP-16  in Florida and sailed on Tampa bay. The thing saved me from heat stroke during sailing  the summer months!  The vinyl is water proof too which is great during rain storms, also I found a heavy duty sewing machine could sew up the cuffs. I didn't notice much windage up to 20 kts, probably because the top is mostly of horizontal construction. Saying all this , if the same top was made for the cp-19 maybe a lighter material would be necessary because of the size.
Bob Burgess had a good design but it couldn't hurt to experiment.

Mike  

Hey Guys,

Glad I checked out this thread.

As an intrepid DIY'er, been thinking about a Bimini for my Sun Cat. Thanks for all the neat ideas and especially the photos - definitely worth a thousand words.

I find the CP-16 forum quite active and informative. Keep up the good work!

capt _nemo

The trouble with a lot of these bimini' s are they provide direct overhead shade when anchored or sailing but not much shade from the sides when a low sun sneaks in under the top.

I like the thought of a Velcro drop down curtain. Much like the drop board cut in half with the upper half in place, blocking the low sun when I may be puts-ing about in the cabin, with companionway hatch slid shut, and with the lower drop board piece stowed away and not in place allowing for cabin ventilation.

skip.

Thanks for the photos and measurements and some of the other ideas. I decided to go with a modified Burgess. I will post some pictures of the final project when complete. I added some cpvc 1/2" pieces to the shroud lines today. Somebody suggested this for preventing the foreward crossbar from slipping down. I capped the cpvc and drilled a hole in the caps . I attached two brass toggles to the 3/4" pvc crossbar so attaching the foreward bar and taking it down will only take seconds. The length of the cpvc height was dictated by the boom height. I wanted the forward bar to be as high as possible without chaffing on the boom.
Another advantage I noted was that when tacking with the genoa, the cpvc should act as a roller and decrease sail wear and tear, so probably a good idea even if you do not intend to add a bimini top.
I plan on making a mock up using an old sheet tomorrow and make sure the size works.
Thanks again for the pictures and ideas.

Quote from: mandolinut on March 15, 2012, 09:09:41 PM
Another advantage I noted was that when tacking with the genoa, the cpvc should act as a roller and decrease sail wear and tear, so probably a good idea even if you do not intend to add a bimini top.

You are absolutely right about the value of rollers on the shrouds.

Although I have not had any real problems with jib sheets or sails on my C-16 dragging on the shrouds, my Catalina 22, which had forward lower shrouds that sometimes got in the way.

The North Sails Tuning Guide for the Catalina 22 recommended shroud rollers.  They were a big help and they cut down on wear on stiching on the genoa.

My only improvement was that, like you, I used end caps and stainless washers to povide a "jewel" type bearing surface on the top edge of the turnbuckle body.  I simply unscrewed the turnbuckle and inserted the stud through the bottom end cap.

However, because the C-16 uses loops to fasten the turnbuckles to the shrouds, you will have to cut a slot in the top end cap to admit the shroud and then use a plastic disc with a similar slot inside the end cap to keep the end cap centered.

When you assemble the top cap and disc, make sure the slots do not line up so the cap will remain centered on the shroud.

I used a small hole saw to cut my discs from a HDPE bucket lid.

Keep us posted.

I'm following this thread, too.  I love DIY projects, and I hope at some point to make one of these tops.

I finished the mock up bimini using an old sheet for fabric. As previously mentioned, I found the height for the forward pvc crossbar easily by going just below the boom in the downhall position. The rear crossbar height took a little more thought. I initially raised the mainsail and sheeted it all of the way in to simulate a close reach and took a measurement of the boom height at the aft end. Cut my 3/4" pvc supports, tightened everything up to the rear cleats and the bimini began to look like a bimini. The problem was the bimini was too low near the back of the boat. I then came up with an idea to make the rear supports adjustable or telescoping. The 3/4" pvc fits nicely into a 1" non schedule 40 pvc pipe (the one with the thinner walls). I drilled a few holes in the 3/4 pipe at various heights for a pin which keeps the 1" pipe from sliding down. Works great.  This way I should be able to have the top raised most of the time sailing and all of the time at anchor.  I also put a T fitting in the middle of the forward and rear crossbars to hold a pvc pipe going down the center for no sag. Works well. 

This is my first attempt at posting photos here at CPYOA. Hope it works. Click on this link or copy and paste it .

http://s1167.photobucket.com/albums/q638/mandolinut/?action=view&current=100_2339.jpg#!oZZ1QQcurrentZZhttp%3A%2F%2Fs1167.photobucket.com%2Falbums%2Fq638%2Fmandolinut%2F%3Faction%3Dview%26current%3D100_2339.jpg

Some pictures of the mockj up bimini and adjustable rear supports. Also a pvc roller furling that allows the sail to be raised and lowered if need be and a dorade ventillation box.

Thanks for the  imput. Next step is to sew it up with Sunbrella.

I forgot to mention, the rear supports fit nicely into stainless life rail supports. Rather than mount and drill holes for the supports, I found two white non skid rubber furniture casters (Ace Hardware) that fit between the stainless support and the fiberglass seat and prevent any slippage.

I am attaching some new photos of the finished sunbrella bimini top. I made two modifications  from others I had seen. One was adding adjustable rear leg supports and the other was a support running down the center of the bimini which takes all of the droop out of the top. You will see pictures without the center support and others with it to show you the difference. I also took a picture of the various pvc pieces needed to create this simple top. To create the center support, I added a "T" in the middle of the front support and a 4 way "T" in the middle of the rear support. I then used a dremel to enlarge the opening so a 3/4 pvc pipe could easily slide through from front to back on the 4 way "T". To install the center support, I first raise the bimini top, then push the support pipe aft through the opening in the middle of the rear support(the one I enlarged). Then I slide it forward into the "T" on the front crossbar. The last step is to hold the center support in one hand, push the rear support aft to make the top tight, and then slip a pin into a predrilled hole in the center support to keep the top tight.

http://s1167.photobucket.com/albums/q638/mandolinut/?action=view&current=100_2366.jpg#!oZZ2QQcurrentZZhttp%3A%2F%2Fs1167.photobucket.com%2Falbums%2Fq638%2Fmandolinut%2F%3Faction%3Dview%26current%3D100_2365.jpg

I also noticed that without this center support, the crossbars tended to bow a bit in the center, allowing for more sag.
Hope this is helpful. Looking forward to trailering her to Ashland, Wisconsin on Lake Superior this summer.

Very well done. Excellent photos. Let us know how it works under sail!

Thanks again.

capt_nemo

I tested the mock up version made from the thin bedsheet material  under sail a few times (  5-15 mph winds) and it worked very well. I also left the top in the up position for a week at anchor with variable wind conditions and no failure. Would have probably lasted at least one season with the bedsheet :0)  The sunbrella will be nice. If I encounter any problems that require adjusting I will let you know.

Note.....holes drilled for the lines securing the rear crossbar should be drilled through the "T" for strength, not the crossbar.

mandolinut,

Where can I find details on your PVC Roller Furling that permits raising and lowering a headsail?

Great idea. Did you make it yourself?

Just finished making a large light air Drifter which will be flown from a 4' Bowsprit on my Sun Cat. Would be nice to try rolling it out when needed, and rolling it back in when not, without going forward. And, all this without buying an expensive foil over headstay Furling System!

capt_nemo

The roller furling was like the bimini top, I saw what others were doing and added some of my own ideas for the cannister. I used 3/4 pvc , capped at the top and glued to the cannister at the bottom. At the top there is a stainless eyebolt passing through the pvc cap with a pully attached rto the eye bolt  to raise and lower the jib sheet.The jib is hanked at the bottom to another eye bolt in the cannister. By using the top pully to raise the jib, you can roller furl the jib without a tangled.
I will post pictures which will make it more clear. I have 7 stainless rings that the jib hanks onto.

I took some pictures of the furling unit made from pvc parts. The drum was fashioned from two 4" to 2" reducers (Home Depot). I cut off the 4" part of the couplers which left the nice angled half drum. Joined them  together with 2" pvc pipe with enough sticking out at either end to attach fittings. I had to use my Dremel to grind off the ridges inside to allow the 2" pvc pipe to pass through. On the top of the drum I attached a 2" to 3/4 inch reducer and at the bottom attached a 2" cap. Shows up pretty well in the photos I am attaching. When the genoa or jib are raised, I take  the free end of the jib halyard , pass it through the eyebolt above the drum, lead it back up the forestay and tie it off.  I use a shortened jib halyard so I don't have too much slack to deal with. Works quite well. I have seen roller furling drums made a number of ways and they all seem to work. The entire assembly  can easily be removed if desired by sliding it off over the turnbuckle since there is an opening at the top of the  3/4" cap that allows it to slip over the turnbuckle.   Hope this helps.

http://s1167.photobucket.com/albums/q638/mandolinut/roller%20furling/

That's an AWESOME DIY furler, Mandolinut!

The block/rings setup is pure genius!  Nice job and suspect you're design will be the new standard.
I also like how it rides over the turnbuckle. More sail area if you get a well cut genoa. Although a bit harder to see under.

A nice salty drum would really make it stand out.

Here's one that Doug142 made for me on the 16.

(http://i188.photobucket.com/albums/z290/yamaholic_mcarp/Compac%2016/PICT7593.jpg)

Hey Salty, I found that with the cut of my genoa, I needed every bit of forestay length which is why I covered the turnbuckle. Otherwise there would have been a lot of slop on the leading edge of the genoa. The most important thing is the furler works well and gives me many jib size options while under sail depending on wind conditions and keeps the deck clear while anchored. Enjoying this boat :0)

mandolinut,

Thanks much for the explanation and excellent photos. A very nice DIY job indeed! I have a only a few questions for clarification.

First, it appears that the 3/4 inch PVC Pipe covers and rotates about the entire forstay with the halyard block attached at the top with an eyebolt. With the tack of the headsail attached above the drum to another eyebolt when hoisting a headsail does this allow you to put enough luff tension on whatever headsail you are using? And, after hoisting sail does the halyard tail, after going through the tack shackle and upwards to tie off on the 3/4 PVC pipe, get wrapped inside while furling? Are you able to get reasonably good headsail shape with this furler? Does it stand up OK in heavy winds, with smaller jib of course?

Thanks again for sharing this information.

capt_nemo

Good questions.
1.  When raising the jib sheet as tight as it will go, the 3/4 pvc pipe has a slight flex until it comes in contact internally with the forestay. Almost like stringing a violin bow. There is a slight curve on the leading edge of the jib. I have not noticed a difference in sailing although there might be if I were racing head to head with a standard rig.
2. Yes, the jib halyard is the cream filled center when the sail is furled since it is running paralell to the 3/4 pvc pipe covering the forestay.
3. I have not had the opportunity to sail in really heavy winds since the furling was installed so cannot comment on performance. It is usually 10-15 where I live in north central Florida on freshwater lakes. The boat will be sailed this summer on lake Superior where whitecaps are common. I will let you know about heavy winds.

I "mispoke" in a previous post.    The forestay is easily removed from the furler by removing the cotter pin that secures the forestay at the top of the mast (with the mast down) and then sliding the forestay down and out of the 3/4 pvc pipe and exiting at the furler drum. The base of the furler drum has a round drill hole in the cap allowing the turnbuckle to pass. A stainless fender washer under the cap acts as bearing.

mandolinut,

Thanks for the answers. Hope you enjoy Lake Superior this summer!

capt_nemo

Mandolinut,

I think your homemade furler is quite inventive and certainly a clever use of materials.  Before I acquired my current CP 16, which came rigged with a furler/genoa, I gave thought to making one.  Yours would certainly make a good model.  

There is one thing I can't help but comment on, and that's the use of push pins for attaching the furler to the bow plate. as shown in your photos.  Since I trailer my boat mostly, I struggle some when by myself to attach the furler/forestay to the bowplate after raising the mast.  The struggle is mostly with the pin/ring combo, with the ring often winding up on the ground below with me kneeling on the bow trying to hold the tension just right while putting in and securing the pin.  I tried a push pin and that sure made it easier.  Then I thought about all the twisting a furler adds to the picture, and decided it wasn't worth it.  

I know there have been comments in recent threads warning about using push pins there, even with forestays without furlers.  I can't say from experience, but I can't help but think the furling action might affect the pin, and since I sail often on a high mountain lake in CO with water about the temp of Lake Superior in the summer, I've decided to be more cautious about that forestay/bow plate connection!

Jett

Jett,
Thanks for your observation and concern. I guess my thinking was I have used the push pins on Hobies for over 20 years without a failure and during that time had a chainplate break and a shroud break from "metal fatigue", both bringing down the mast. It is often the things we do not worry about that bite us on the butt.
I will take your advise this summer and use a standard shackle since I plan on leaving the mast up in a marina for two months. Probably for a Florida day sail I will stick with the pin. Much easier when you are by yourself. Push pins must be kept oiled and free of sand :0)  Thanks again for your concern.

Ah, the little things...just snapped off the pivot pin lever/nut on my rudder while tightening before my last sail a couple of days ago. (Metal fatigue?).  Into the drink.  At least what remained of the nut held tight while sailing.

BTW, took out a Hobie 16 once years ago and had a blast riding up in the air on one pontoon.  Never learned how to tack it properly, though I did manage to keep the thing right side up!

I have two boom supports now. a higher one for daysailing to use at anchor and keep the boom from swaying above the bimini and theis new one for trailering.
http://s1167.photobucket.com/albums/q638/mandolinut/?action=view&current=100_2381.jpg