Trick of the Trade?

[SWA]

Getting ready to attach the dagger board trunk to the hull. After trying to fair it in I am still a little better than a 1/8 of an inch off. Wonder if there is something that I can put on the bottom of the boat (graphite??)that will show me the high spots that first come in contact with the boat. Not sure what an acceptable tolerance is or how much the bedding compound will forgive.

Steve

[Ken Hutchins]

Set it in place and measure all the gaps with feeler gages, note on the box the location and the gap, do this every 2 or 3 inches all the way around. Then remove the high spots. The amount to be removed from the highest spot is the amount of the maximun gap, if you have an area of let's say with a .040 gap and the maximum gap is .125, then the amount to remove from the area with the .040 gap is .125-.040=.065. etc. initially cut narrow grooves at the spots to the correct depth, then blend all the surface to the bottom of the grooves. Carefully do it by the numbers and you will have a perfect fit in 1 or 2 fit ups.

[Bob Smalser]

Make a pattern of cardboard or doorskin to get your trial and error cuts done there instead of your bedlogs.

Otherwise, chalkline chalk in a the squeeze bottle it comes in makes a decent "indexing fluid".

Bedding compound won't close a gap for long.

[ 12-13-2005, 07:48 PM: Message edited by: Bob Smalser ]

[FSS172]

Hi Steve - Another method is to dust the joining surface of the keel/keelson with chalk powder - the kind that's sold to coat chalk lines. Bring the trunk into position and wiggle it slightly. The chalk will transfer to the high points. Plane these off and repeat till it fits. No measuring, no math.

Well, Bob got in there first... but we're both describing the same method.

Jim

[ 12-13-2005, 07:55 PM: Message edited by: FSS172 ]

[kc8pql]

About 40 years ago, when I was in highschool, I applied for a summer job helping a finish carpenter. He asked me some questions and I thought I had the right answers. Then he asked to see my tool box. I had all the basics. They were good tools and I was proud of them. He took a look, kind of grunted and asked me if I had a sister. That took me back a bit but I said yes, I did. He told me to steal one of her lipsticks and put in my box. Be there ready to work at 7 o'clock Monday morning. About a month later, while we were fitting new doors into old jambs, I found out what the lipstick was for.

[Jagermeister]

Ellis taught us the following technique for fitting floors, etc.

Use a strip of 2" cloth backed sandpaper. The red stuff. Place it between the two pieces to be fitted, put some pressure on the joint, and drag the paper out. It will leave a red mark from the paper side which will show the high spots. You may have to repeat a few times to get a dark mark. The paper doesn't have to have sanding ability left, so its a great use for worn out paper.

P.S. Actually, come to think of it, worn out paper is probably best, since you want the pressure to rub off the dye from paper backing, rather than the grit. Maybe if Ellis sees this he can correct me if I've got it wrong.

[ 12-13-2005, 08:33 PM: Message edited by: Jagermeister ]

[Ken Hutchins]

No measuring, no math.

But if you do the math you will know how much to remove and where to remove it, otherwise it is a guessing game.

[Bruce Hooke]

Steve,

You've gotten some good advice so far. I'll just add a suggestion or two about the thought process to apply. A lot of the time with this sort of thing I find that the problem is not just finding a way to mark the high spots, but also going slow enough as you remove the high spots so that you don't go to far. A few passes with the plane can make a lot of difference, so stop frequently and check the fit. As you get better you will be able to get a good fit without a lot of testing and adjusting, but when you are learning and trying to get something like this to fit it is important to keep checking the fit. Do your best as well to make sure that you KNOW where you need to take off more wood, rather than guessing. Guessing will almost always get you deeper into trouble rather than out of trouble.

[Thorne]

Just went through this with my centerboard case. All the above methods are the 'do it right' way -- then there is the quick and dirty way...

;- )

I just marked the side of the case where my feeler gage showed gaps, then pulled it out of the boat and belt-sanded the unmarked bottom sections of side planks for a second or two, then fitted it again. Repeat as necessary -- carefully, of course.

That plus some Vulkem 116 as bedding seems to work just fine.

Bigger problem was getting the #10 wood screws that hold the case to the bottom to go in straight -- several wandered off course when drilled in from the bottom and nicked the outside of the case slightly.

I used a drill with a bubble-level and both a proper countersink bit with short tapered drillbit, and a longer straight drill bit for the threaded end. And the screws were lubricated with red lead paint, which probably helped a lot in that hard white oak.

So watch the attachment part once you get the case clamped into place for installation.

[ 12-13-2005, 11:05 PM: Message edited by: Thorne ]

[wyndham]

Thorne, next time drill the bedlogs down from the top. Then go under the boat and countersink. Clamp the case in place and using the predrilled holes run the bit up into the case.

[FSS172]

Bruce's excellent advice suggests one other thing to keep in mind. As you're positioning the trunk for this fitting process, ensure that it's accurately aligned both fore/aft and athwartships as it comes down to meet the joining surface. Do this even if it means that the trunk only contacts the surface below on one side or in one or two places. Then carefully plane off only those point or points of contact that the chalking indicates. This will ensure that once you've closed the gap, the trunk will be standing as it's supposed to in relation to the hull.

[Old Bingey]

You used to be able to get that chalk line chalk in a hemispherical chunk but I haven't been able to find it for a long time. It was good to rub on something to find out where it was touching something else. That powdered chalk is messy to my notion. Now I use children's sidewalk chalk.

I also like those Japanese hacksaw blade looking rasps for fitting things like that.

[Bill Thompson]

I lost my chauk marker / holder about two years ago and have been trying to replace it ever since. Most "home improvement" stores sales folks have no idea what I'm asking for and always point out the marking crayons. A few of the remaining hardware store guys know about the chauk markers or the hemispherical chauks but the response had been: "Sorry, we don't carry those anymore."
These days, I know every thing on a shelf in a store is analysized for sales per quarter, inventory turn over, etc. etc. and if doesn't move, its not stocked anymore. But it has gotten to point that I now expect not to be able to get something from hardware stores; auto supply stores (local NAPA doesn't carry exhaust gasket sheet material???); industrial supply houses. If I am lucky the counter person might have a clue about what I am inquiring about and know where to find it in a jobber catalog. If all goes well, I will be able to order (and pay in advance) the item and plan to make a return trip in a few days or week to actually get the item. Meanwhile whatever I was working on comes to a halt.
Last part of the rant - where did all of the "old" supply house and hardware store guys who knew everything about the product and sometimes about its use and application go? Their replacements generally do not have a clue; I am not speaking just of big box stores but of some of the supply houses as well. Recently, I needed to get silicon grease for rubber seals at Grangers - counter person had never heard of it...I ended up looking through their counter catalogs to find it. At least they had it in stock. I know I also got the last container (about 7-8 years ago) of silicon grease at Grangers (albeit a different store), I recollect that the counterman said 'sure - food grade or industrial?" and walked down the aisle, grabbed a jar of Permantex silicon grease and, after payment, handed it over.
Must be getting old -

[Old Bingey]

No,Bill it ain't that we are getting old, it is just that most other people are ignorant.... educated by the TV. They know all about custom choppers but couldn't cut a gasket to save their lives. That's why you can't buy gasket material. Which, that's the trouble with getting old. I have a lifetime supply of gasket material. Rats.

[Ken Hutchins]

Just like going into the GE Supply place and asking them for a surge protector to go into the main circuit breaker box in my house and getting told that "NO SUCH THING IS AVAILABLE" well sez me don't give me that crap I know GE makes them. He sez "NO THEY DON"T. I say B##$ S&^% I work for GE and I made the mold for the plastic housing so don't tell me there is no such thing. Then I had to show the dumb SOB how to open the catalog and look it up, sure enough right there, then he looks it up in the computer and finds out that there are 1/2 dozen sitting on the shelf.

[stef]

Cheap trashy chalk block solution.

Go to the toy aisle* and get some side walk chalk. It comes in a rainbow of colours. [img]smile.gif[/img] You probably do not need to get the large tub.

Stefan

*not at Lowes or Home Depot

[ 12-14-2005, 04:56 PM: Message edited by: stef ]

[FSS172]

Sidewalk chalk - great idea. And you can pick a color to suit the mood you're in that day... [img]smile.gif[/img] But if you really want those hemispheres go to

McMaster-Carr

and search on 'chalk cake'. In case you've never dealt with them, that company is amazing. It seems like they've shipped before you're finished ordering and, at least where I live, you get next-day service at ground rates.

[FSS172]

Sidewalk chalk - great idea. And you can pick a color to suit the mood you're in that day... [img]smile.gif[/img] But if you really want those hemispheres go to

McMaster-Carr

and search on 'chalk cake'. In case you've never dealt with them, that company is amazing. It seems like they've shipped before you're finished ordering and, at least where I live, you get next-day service at ground rates.

[gert]

this thread is being hijacked

So what the heck

My local Rona (Canadian home despot) doesn't sell 94" band saw blades cause nobody has asked for one in 10 years

[ssor]

Originally posted by Ken Hutchins:
Just like going into the GE Supply place and asking them for a surge protector to go into the main circuit breaker box in my house and getting told that "NO SUCH THING IS AVAILABLE" well sez me don't give me that crap I know GE makes them. He sez "NO THEY DON"T. I say B##$ S&^% I work for GE and I made the mold for the plastic housing so don't tell me there is no such thing. Then I had to show the dumb SOB how to open the catalog and look it up, sure enough right there, then he looks it up in the computer and finds out that there are 1/2 dozen sitting on the shelf.

You just got a lazy clerk.

[Mrleft8]

Get a small piece of wood (1" square) cut it to the thickness of the largest gap between your daggerboard case and the keelson. Lay a sharp pencil on this so that the tip is level with the top of the block. With one hand move the block around the case while holding light, but firm pressure on the pencil against the case with your other hand. The resulting line should give you a very nice fit.

[Nordicthug]

You'd be amazed how many hardware stores still have either "railroad" chalk, the white stuff in a stick about 4" long and 3/4' diameter that works well for chalking in timbers or the blue hemispherical "carpenter's" chalk.

I think the sidewalk chalk is a capital idea.

Gerry N.

[Steve Miller]

Most any flooring supply wholesaler that caters to flooring installers will have chaulk in various colors available in plastic bottles for re-filing chaulk lines. We sell several colors. Flooring installers use chaulklines everyday.

[SWA]

Thanks all for the responses. Will give them a shot this weekend.

Steve

[Chan]

I agree with mrleft8,only easier, take a carpenters pencil, you know those flat rectangular ones, hold it on the keelson or whatever and scribe the damn line. Also guys you can probably find those chunks of chalk you're talking about at a masonry supply store. I'm suprised your local lumber yard doesn't have them, or are you guys going to THE HOME DEPOT, God forbid!!!!