13 February 2018

DTC Coping saw introfit

Work in progress
I finally bought a Knew Concepts coping saw. Of course, I've been lusting after one since I first tried out a model while still working at Harvey. I planned on buying one from Lee Valley and schlepping it back through customs during my last trip to the States. I had to reduce the economic impact of that order for marital reasons and so the high priced piece of aluminum was deleted from the shipment.
During my work developing the children's classes, however, I was introduced to a local Taobao merchant, Plawood, that carries the Knew Concept saws. I was a bit confused and examined the sample attentively, thinking that it must be shanzhai since Harvey has exclusive distributorship on the mainland.
I cannot explain what the business relationship is between Plawood and Harvey, but it's evident that Plawood is selling items imported by Harvey. Is this an example of outsourcing the domestic retail distribution of the woodworking imports? It seems that they might even reexport internationally as long as one doesn't order during the lunar new year holiday. It's yet another market mystery with Chinese characteristics. I was not allowed to leave Harvey with any of the tools that I was encouraged to purchase while there and thus I swore not to ever buy from them again. This latest development somehow carved out a workaround to this dilemma.
Photogenic and visually available
And now with the saw in hand, I tasked myself with making a home for this coping saw inside my toolchest. There is inherently a trial and error approach to this sort of project. Like most tool users with access to the internet, the first step typically involves searching online for other examples of whatever we are trying to make. I don't know whether this method is more inclined to generating inspiration or more about procrastinating. Despite the growing collection of handtools cluttering the DTC since I first built the fixtures to secure my LN saws, I knew that there was still enough room for this addition, but it would be tight fit and a compounded challenge.

My first prototype was meant to take advantage of the strutwork of the frame. I think I was overly influenced by online examples, believing that there needed to be knobs and holddowns with springs or threaded fixtures to make this work.
First internetworthy prototype
Certainly there were many contact surfaces to help support it, but I still needed to find/fabricate some sort of springy tines or turnknobs in order to complete it. I found some springclips for hanging clothes that would have required cutting, drilling, and coating the tips with rubber to prevent from scratching the softer aluminum. There was still some doubt as to whether these would hold securely and not fail over time. This design process endured a few days as I considered possible mechanical solutions, visiting the nearest B&Q to stock up on from their very limited supply of fasteners. But I did get sucked into buying another metric/imperial tape measure and a pump sprayer for the phalaenopses.

During one of my commutes and inspired by the aetheric spirit of John Harrison, I abandoned this prototype and reimagined another. By the time I arrived at the woodshop, I had the steps in how to cut the fixture plotted ahead mentally. To be clear, I screwed up the first attempt by crosscutting the back of the grooved section, but it was easy enough to make a second which is shown.
Friction fit
I still thought that I needed to apply at least one turnknob at the top, but the friction is enough to keep the aluminum frame secure. With this sort of arrangement, I might need to wait until the summer humidity proves this design's parameters. If there is any excess looseness then, I can readily add some sort of improvised hardware to solve the issue.
It was necessary to undercut the back to allow for the slides that hold the beam to a panelgauge.
The coping saw in its new home
Gongxi Facai!


Gabe D. said...

Thoughtful work! May I ask, what do you use the coping saw for? I really like my Knew Concepts fret saw and have really thought about the coping saw for cutting cope on interior trim. Does it hold tension nicely? Not too much plastic? The fret saw (five years ago when I bought it) has little plastic knobs for holding the pinless blades, for the price they really should have made them out of brass or steel.

Gabe D. said...

Oh, awesome John Harrison reference. His work with the marine chronometers is my favorite bedtime story!

Potomacker said...

@ Gabe D.
I cannot speak for the whole range of Knew Concept tools but I would simply direct this issue about the plastic knobs to their customer service department and inquire about possible upgrades. Equally, Lee Valley sales service might have suggestions in this regard.
If you do any metal work, I think the fretsaw is a better option since it allows a greater range of blades. I don't think I would have bought the coping saw without having read about the high quality of Pegas blades. The cam action makes detaching and reattaching blades relatively frustrationfree.

I never developed a habit of using a coping saw on dovetails so I've been able to do without. I have, however, a project in the pipe that shows off what would have been impossible without such a saw.