Tuesday, February 15, 2011

Tech Tip Tuesday

Today's post is on staplers. While it isn't necessary to use staplers to build a cedar-strip canoe, I find that for beginners, they are particularly helpful in getting good results on your first canoe. For subsequent canoes, if you want to go staple-less, fine, but learn what you are doing first as far as the building process goes. In particular, I think staplers are one of the more critical tools in the process and some subtle things can really help or hurt the cosmetics of the finished canoe. I'll show you why in this post.

Below are a few of my staplers. At the top left is a typical Arrow-brand hand stapler. (an older model) At the bottom left is an electrical stapler made by Stanley. The two on the right are different generations of the PowerShot staplers.


The traditional style stapler works OK , but the force that you apply is away from the point where the staple is being dispensed. This can cause issues with not driving the staple deeply enough - particularly at the stems. The electric stapler was OK, too, albeit a bit bulky - but the main problem was with the cord - it was always in the way and we always seemed to be moving it around. While I don't show an air stapler here, I find the same things to be true of the hose as I do for the cord. I have come to like the PowerShot style staplers for their reliability and ease of use. The do take a bit of getting used to - people try to use them backwards thinking the staple exits at the "heel" like a traditional stapler - but once you get used to them, I find that applying force over the staple exit makes lots of sense.

As you can see in the picture, the two PowerShot staplers look almost exactly alike except for the blue tape at the finger hole. The blue tape is for a very specific reason. I use both 1/4" and 9/16" leg length staples to build canoes and I need to know the difference. Why, you may ask? If you've ever been backing up 1/4" thick strips with your hand and accidentally drive a 9/16" staple through the strips and into your finger, you'd know why! OUCH! The tape tells me which size staples I've loaded in the stapler.

In theory, you drive the 9/16" long staples at the stations to hold the strip to the station as the glue is curing. You also use them to hold the strips to the stems as the glue there is curing. If they are in a neat row on the forms, the holes will draw the eye less then poorly aligned staples. The 9/16" long staples should be aligned with one another as best as you can and driven in the center of the strip so as not to pass through the cove or bead on the strip (if you're using cove and bead...) You do NOT want the 9/16" long staples to bridge across the strips (i.e. one leg in each strip) as this causes problems with strips staying on the forms. Because the back of the strip is supported by the forms, there should be no chipping on the back side of the strip.

The 1/4" long staples are intended for holding the strips together between the forms. Unlike the 9/16" long staples, they are intended to bridge between two strips to hold the joint closed as the glue sets. Anywhere there is no backing to drive a longer staple, you should use the shorter 1/4" staples. As noted above, this is a whole lot easier on the builder's fingers. Smaller gage staples are fine here - they will be less obvious when removed.

If you simply take a stapler and start building your canoe, you will get the following results -
Note that the staples have been driven below the surface of the strip:


This is the back of the strip - note that both the 1/4" and 9/16" staples have broken through and chipped out the back of the strip.


I should note here that the back of the 9/16" long staples is only breaking out the back of the strip because there isn't a form backing them up, and that the 1/4" staple should not break through, but has because it has been driven too deeply.

This is the front of the strip after the staples have been removed:


These dents will show up as "bruises" on the surface of the canoe even after you have faired and sanded them out of the surface of the canoe. This is from the tearing and deformation of the wood fibers. If you look carefully, you will also see a small circular dent from the staple remover.

Darn.

But I don't want my canoe to look like that with a line of bruises.

Is there a solution?

Yes.

Masking tape.

Masking tape?

This is the sole of one of the PowerShot staplers. I've applied a strip of tape to the sole to keep any glue out of the mechanism. I've also built up 7 layers of tape near the point where the staple exits. (Your mileage may vary - you might need more or less tape depending on how thick your tape is, how much force you apply, etc., etc...) This will raise up the sole of the stapler so that they will not be driven so deeply. The downside is that I need to pull this off when I need to refill the stapler, but it's worth it.


Here's the "mouth" one of my long-used Power Shot staplers where the staple exits without tape. If you'll look, you'll see that other than a bit of dust it is very clean.


This is very important. When you are applying staples to the canoe, you want the stapler to function well. If it is all gunked up with glue, the stapler can jam and will not work smoothly. It's frustrating when you're trying to apply strips only to find that the stapler isn't working well and you have to clean it up as your glue is setting on the strips...

So, here are some staples that have been applied with tape applied as shown above.


You can see visually, that they aren't driven below the surface of the strip. This has several major advantages. First, we won't get the dent noted above. Second, as seen below, the tips of the 1/4" staple don't break through the strip. (The 9/16" staple still does as it wasn't "backed-up" by the forms.)


Third, you can get a staple remover under the staple to lift it more easily and as I said, there's no dents!


There are still staple holes, but these can be swelled shut with a steam iron and a damp cloth when the hull is complete and the staples removed. They will still be a dark dot because the tearing of the wood fibers made by the staple going through the strip, but this cannot be avoided when stapling strips.

I should point out that you can apply tape to the sole of the stapler and still get the dents from the staple's crown. You need to keep the sole of the stapler on the hull like this:


NOT like this (note raised heel of stapler):


If you drive staples like in the last picture you'll still have dents - tape or no tape.

Methods and technique solve this issue.

2 comments:

Anonymous said...

canoez: Thank you for the stapling primer. So far so good for me. I'm using a T-50 or whateva they call it and 9/16's. The staple heads always stay proud, so I haven't been denting the strips. It is working fine so far. I also like the masking tape clamps to hold the strips between stations. I do need to find a good staple puller....Cheers, Fitz.

Canoez said...

Fitz,

It is looking good. Yup. That's a T-50 your probably using - big silver jobbie. Make sure you remove all the residue from the tape. When you sand and fair the hull, you'll find that most of it should be removed.

Ironically, to remove the staples you want to go to Staples - the office supply company. You want their item number 264093, for $11.49. I like this part and know that Nick Schade likes it as well.