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Re: Strip: sanding vs planing
By:Rob Macks
Date: 4/4/2003, 11:35 am
In Response To: Strip: sanding vs planing (James Nixon)

: Hello...I just reached the planing/sanding stage of a night heron kayak, and
: I've found planing with a block plane (as described in N. Shades kayak
: book) to be a bit troublesome. I've noticed that the edges of the plane
: tend to put dents into the softwood on the kayak, and the mix of hard and
: softwoods to make it difficult to judge the pressure. I've opted to sand
: it instead, and the new orbital I bought seems to take forever and go
: through paper very quick. Against my own worries of cutting right through
: I went ahead and used a circular grinder style sander (initially bought as
: a buffer) and it seems to work well except it doesn't collect the dust. Is
: this crazy or does anyone else find the other methods tricky/cumbersome?
: Any suggestions and comments from someone who has faced this problem would
: be helpful. I've tried sharpening the plane and adjusting it every which
: way, but still gives me problems. I imagine the hull will be easier
: because it has virtually no hardwood. I'm just worried about wrecking the
: last 4 months work, but also don't want it to take another 3 months
: either.

My hope is that some will find this helpful. I don’t wish to start a fight, just some thought.

Please consider this:

The beauty, the genius, of the strip building method is that IF the wood strips remain in contact with the stations & stems, AND the edge of each new strip is aligned and glued to the previous strip, the resulting surface IS FAIR and nearly perfect.

THE RESULTING SURFACE IS FAIR AND NEARLY PERFECT!

This is the essence and genius of strip building theory

ONLY sanding to level the high points along the strip joints and to smooth the surface for finishing, is needed. A narrow surface down the center of each strip is perfectly fair, just as a plywood panel on a stitch and glue boat is perfectly fair.

The less you do to this surface the more it will remain fair!

The random orbital sander allows the builder to take advantage of the strip building method in a way no other tool can. The random orbital sander uses the FULL FLAT SURFACE of the sanding disk to ride on high spots and level the surface TO the lowest point of VISUAL REFERENCE, in this case, the narrow surface down the center of each strip which is perfectly fair.

You cannot create a fair and regular surface with random tool use.
You must carefully define the areas to focus tool use.

For example, if you hope to make a round or oval paddle loom you must carefully mark off the edges of the loom stock in equal sections for removal and work methodically to create regular facets to make the transition to one regular continuous plane.

Imagine working on a stitch & glue boat using a aggressive edge cutting sander or a plane on the plywood surface. You would quickly cut through the top veneer, destroying the fair surface naturally created by the plywood panel .

It just doesn’t make sense to work a fair plywood surface with a plane or edge cutting sander. It should make just as little sense to work a well stripped, fair hull with a plane or edge cutting sander. It will be counter productive.

If you take the time to align your strip edges your hull will be nearly perfect. There is no need for aggressive surfacing.

I do understand that quite a few builders have difficulty in aligning strip edges

Traditional strip building technique uses 1/4” strips and staples or brads to FORCE strips into place in the most difficult areas around the keel/stems. While this worked reasonably well for simple football shaped hulls, for more complex modern hull shapes, kayak shapes and stapless stripping methods, 1/4” traditional force stripping, makes perfect alignment of strips near the hull keel/stems very difficult.

I’ve developed a number of modifications to the traditional stripping technique to solve these problems.

The three big differences in my stripping technique that make stripping considerably easier are:

First, use 3/16” thick strips instead of 1/4”. 3/16” thick strips are more flexible and are easier to twist, bend and align.

Second, use northern white cedar to strip below the waterline. The area below the waterline is the most difficult part of the hull to strip. Northern white cedar is more flexible than other softwoods and has always been the preferred wood for canoe building for hundreds of years because of it’s bending properties.

Third; Use a heat gun to apply dry heat to bend and twist strips into place instead of relying on force. A heat gun boils the water in the wood to bend without having to wet the wood. This allows you to glue immediately without having to wait for wood to dry as you would it you used a wet/steam heat method. The heat gun applies local heat to a small area so you don’t need a large box or other apparatus. There is no waiting, no spring-back as in wet bending. Northern white cedar is the best wood to utilize the heat gun method of bending for the already stated natural bending properties. But also, because NWC is typically air dried, the natural glue (lignin) which holds the wood fibers together can be reactivated by heat. Kiln drying wood alters the lignin and it will not respond as well to heat/steam bending.

Using 3/16” strips RELIES on the proper use of a random orbital sander to level and smooth the strip surface. A random orbital sander works like no other surfacing tool by riding on the high spots. The round pad and random stroke will not cut into a surface as long as the full pad is held FLAT against the work surface. IF the ROS is HELD FLAT against the surface IT WILL produce a fair surface. THIS IS CRITICAL TO SUCCESS. The ROS is moved over the surface until a uniform sanded surface results. You must assess the progress VISUALLY. The original unsanded surface is your visual reference letting you know when to move on. This will happen JUST as the lowest center of each strip is sanded in each area. Then you must move on. This sanding method takes off very little wood. Rough sand the surface with a random orbital sander and 60 grit paper. Then WET, I mean WET the surface to raise the grain. The cut marks from the 60 grit paper will disappear. All dents and staple holes will raise and close. After the wood dries you can sand with 120 grit because the soft wood needs no courser grit to proceed to finishing steps. I finish the surface with 220 paper to bring out the deep luster and beauty of the wood.

Other sanders or the ROS itself CAN be very aggressive if weight and power is applied with an edge or only part of the sanding pad. This will result in an irregular surface. It is common for people unfamiliar with sanding to use a fine sandpaper grit and when it does not level the surface quickly, to use an edge of the sanding disk to aggressively remove a blemish to cut into a low spot. This is a mistake and will leave an unfair surface. This is why use of the ROS calls for a courser 60 grit paper which will level and fair the surface quickly. It is important to use a soft backing pad on the ROS because this will conform better to the curved surfaces of a boat. After rough sanding with 60 grit the wood should be WET down to raise the grain, raise dents and close any staple holes.

These stripping techniques and the random orbital sanding method I describe above are the foundation of the boat. Each step is interlocked into the next. If you can’t bend strips you can’t align the edges and if you can’t align the edges you will have to sand more or plane to establish a common surface and you will destroy the natural fair surface created by using wood strips. If your strips have not naturally created a fair surface the ROS will follow the irregularities of that poor surface.

I urge you to focus your attention on tacking each strip solidly to your stations and pre-fit, clamp, bend and twist each strip with the heat gun so you can align each edge as perfectly as possible. This will reduce work on every future step. Less IS more in strip building. If you work to align your strips the surface will be very near perfect and you will have less work smoothing the hull.

AFTER you have stripped your hull, if you have strips that are mis-aligned 1/32” or more, then fix the strip alignment before sanding. Use a razor knife and cut on the joint, apply glue and realign the strip edges.

If you use 3/16” strips they will be more flexible, if you use northern white cedar it will be even more flexible and if you also use a heat gun to bend and twist strips into place you will find it very easy to strip a perfect fair hull or deck. Any one of these suggestions will make stripping easier. If you will use all three suggestions you will find stripping a totally painless dream.

I’m not trying to put down others working technique. WE all love boat building here.
I’m offering you a look at the ideas that guide my work process.

I’m suggesting that by understanding the basic theory of strip building By looking at WHY we are doing something, we can focus our labors in areas that are most productive and eliminate random and counterproductive steps.

I hope some of you, especially new builders will find this useful.

If you are happy with the way you are currently working then by all means, continue.

All the best,
Rob Macks
Laughing Loon CC&K
www.laughingloon.com

Messages In This Thread

Strip: sanding vs planing
James Nixon -- 4/3/2003, 1:40 pm
Re: Strip: sanding vs planing
Rob Macks -- 4/4/2003, 11:35 am
Re: Strip: sanding vs planing
KenC -- 4/4/2003, 3:58 pm
Re: Strip: sanding vs planing
Rob Macks -- 4/4/2003, 5:21 pm
Re: Strip: sanding vs planing
James Nixon -- 4/4/2003, 3:02 pm
Re: Strip: sanding vs planing
Rob Macks -- 4/4/2003, 3:38 pm
Well said...
srchr/gerald -- 4/4/2003, 1:52 pm
Re: Strip: sanding vs planing
Dennis -- 4/4/2003, 1:45 pm
Re: Strip: sanding vs planing
Rob Macks -- 4/4/2003, 2:57 pm
Re: Strip: sanding vs planing
JJ Atkinson -- 4/4/2003, 1:28 pm
Re: Strip: sanding vs planing
Brian Ervin -- 4/7/2003, 10:18 am
Re: Strip: sanding vs planing
Nick Schade - Guillemot Kayaks -- 4/4/2003, 3:51 pm
Re: Strip: sanding vs planing
Rob Macks -- 4/4/2003, 2:33 pm
Re: Strip: sanding vs planing
Shawn Baker -- 4/4/2003, 3:50 pm
Re: Strip: sanding vs planing
Jay Babina -- 4/4/2003, 9:39 am
Re: Strip: sanding vs planing
KenC -- 4/4/2003, 9:02 am
Re: Strip: sanding vs planing
Ted Henry -- 4/3/2003, 3:47 pm
Re: Strip: sanding vs planing *Pic*
Brian Ervin -- 4/3/2003, 2:23 pm
Re: Strip: sanding vs planing
Dave McKinney -- 4/3/2003, 3:39 pm
Re: Strip: sanding vs planing *LINK*
Mark Normand -- 4/3/2003, 8:51 pm