pins blew out wood because of too tight fit
I just did a test fit with 10 dowels using Jessem's own dowels.
http://www.thetoolstore.ca/viewItem.asp?idProduct=16725
I had to use a clamp to dry fit the pieces because the dowels fit so tight. The joint split in several places.
I had to use pliers to remove the pins, and one pin wouldn't come out without my having to bust it out. I measured the pins with a caliper and noted that they tended to be 1/128 inch larger than 3/8''.
I then tried other dowel pins. The only dowels that fit easily are the ones made in China, dowels that are probably technically undersized.
Next, I used Dowelmax's bit to drill a hole. All pins fit easily in this hole.
I can't fathom why Jessem changed their bushing so the 9.7 mm dowelmax drill bit no longer fits.
1 Attachment(s)
Jessum Pins with Jessum Jig
Quote:
Originally Posted by
Paulh Tremblay
I could have used a mallet to hammer the joint together, but I don't believe you should fit dowel joints together that way. The videos for Jessem and Dowelmax show the joints going together easily with the push of a hand.
Has anyone experience with the dowel pins sold by Jessum? I would expect their pins to match quite well with their own jig. Seems better to me than the various re-sizing schemes discussed in this thread. I haven't yet ordered them but plan to give them a try.
The company describes their pins:
Our pins absorb some of the glue moisture and expand to take up the space left by the shrinking glue, creating an excellent mechanical and chemical bond.
Our Expansible Dowel Pins are milled round and slightly oversize, then grooves are impressed into them creating an accurate, strong, joinery element.
Jessum Dowels & Jessum Jig: Good Match?
Quote:
Originally Posted by
Paulh Tremblay
I did two tests with these dowels. In the first, I used the dowels out of the bag. The dry fit was so tight I actually had to break a dowel to remove it. I did not even try a glue up.
In the second test I microwaved the dowels for 2 minutes. They fit nicely during the dry fit. When I glued the joint together, I needed 4 clamps for a 16'' piece. I just checked a minute ago and saw the test piece had developed a crack because of the excessive pressure. I may have used too much glue.
Paulh, from Bill Huber's comment about two sizes of drill bit it seem important to know which size you used. Your results indicate a mismatch in your test. You didn't specify which dowels you used in the test but presumably they were Jessum, right?
What we need to know from someone's experience is: whether the Jessum dowels work without complications in the Jessum jig with what drill bit?