View Full Version : Incra Jig
sbolton
23rd October 2007, 02:08 PM
I cut my first half blind dovetail this evening on my Incra Ultra jig. The joints fit snug, but there are gaps as I hope the attachment reveals. How do I get rid of these gaps?
Any ideas?
Thanks
sb
Pusser
23rd October 2007, 02:16 PM
It may be an optical illussion but the top board does not look flat (put a ruler accross the picture to avoid the optical illusion caused by the grain). This would cause gaps I think. Is the vertical board square? Unless these two conditions are met you must get gaps of some sort. Then again I might be deceived by the photo,
Pusser
sbolton
23rd October 2007, 02:20 PM
The top is flat. It may be the camera work. I thought the boards were at 90 degree angles.
sb
Pusser
23rd October 2007, 02:38 PM
OK. Then you will probably need more knowledgeable help than me on the subject. Most of that will come on line this evening in Aus ( its about 1.37pm here). All the best will follow responses with interest.
Pusser
Sprog
23rd October 2007, 02:55 PM
Is your table dead flat?
Is the fence square to the table?
Is the stock dead flat?
Did you set the depth of cut accurately?
Did you centre the workpiece accurately?
Was the tail board firmly clamped to the right angled fixture?
Was the pin board pressed firmly down onto the table and up against the fence?
wheelinround
23rd October 2007, 03:08 PM
I cut my first half blind dovetail this evening on my Incra Ultra jig. The joints fit snug, but there are gaps as I hope the attachment reveals. How do I get rid of these gaps?
Any ideas?
Thanks
sb
Hi SB think you might find your timber isn't flat/square/even I have placed a box over the top these are 4mm lines and as you can see to the right top it lifts
while the bottom piece is uneven also
sbolton
23rd October 2007, 03:25 PM
You are probably right. How did you put those lines on the picture?
Thanks
sb
wheelinround
23rd October 2007, 03:26 PM
You are probably right. How did you put those lines on the picture?
Thanks
sb
Corel Draw
Do you have a marking gauage this should let you know for sure http://www.technologystudent.com/equip1/mgauge1.htm
martink
26th October 2007, 01:05 AM
You know what, it looks like your fence is not at 90 degrees to the table or your table is not flat (i'm guessing the later). If the timber is not dead flat against the fence and table top then I've seen this happen - I got this result with a very slightly uneven router table top. When that say it's good to have a dead flat router table top, they mean it!
ciao,
M.