I would like to build some stretcher frames for painting. They use a
complex miter joint at the corners. It looks like the joint would
require a combination of bandsaw cutting and table saw cutting to high
precision. It can best be described as a 45 degree section on the two
top and bottom parts with two center parts making a lap joint.
This is typically done on pine with a thickness of 1" to 1.5".
Can anyone give me advice on the effective way to cut the joint?
Dick
You would be better off stretching/restretching the canvas with the proper
pliers.
Miter sled/tenoning jig for the tablesaw will do 'em, but IIRC it's six
passes.
"Richard Cline" <[email protected]> wrote in message
news:[email protected]...
>
> I would like to build some stretcher frames for painting. They use a
> complex miter joint at the corners. It looks like the joint would
> require a combination of bandsaw cutting and table saw cutting to high
> precision. It can best be described as a 45 degree section on the two
> top and bottom parts with two center parts making a lap joint.
>
> This is typically done on pine with a thickness of 1" to 1.5".
>
> Can anyone give me advice on the effective way to cut the joint?
>
> Dick
Unfortunately, with the 1/2 laps, one part you might need to adjust is
covered by canvas, and a devil to adjust with wedges. This joint takes a
tenon jig and miter jig to do well, but adjusts a lot easier. Still, the
big stretcher pliers and a stapler do a credible job, though not necessarily
on the first attempt, unfortunately
"Phisherman" <[email protected]> wrote in message
news:[email protected]...
> If you are going to cover the frame with canvas just make half lap
> joints using the table saw. If more strength is needed, saddle joints
> provide more glue surface area but for this you'll need to build a
> table saw jig (unless you have a mortising jig.)
>
On Thu, 30 Sep 2004 20:00:12 -0700, Richard Cline <[email protected]>
wrote:
>
>I would like to build some stretcher frames for painting. They use a
>complex miter joint at the corners. It looks like the joint would
>require a combination of bandsaw cutting and table saw cutting to high
>precision. It can best be described as a 45 degree section on the two
>top and bottom parts with two center parts making a lap joint.
>
>This is typically done on pine with a thickness of 1" to 1.5".
>
>Can anyone give me advice on the effective way to cut the joint?
That's done with a lock miter bit for your router or shaper.
Dick,
If I'm imagining the joint correctly, it sounds like a mitered-corner
lap joint and is desciribed in detail in Yeung Chan's book, "Classic
Joints with Power Tools" on page 96. He says it is commonly used in
frames and, though it looks complex, it is fairly simple to do on the
table saw if you follow the right sequence (which he shows you).
I was just looking at this book for ideas about how to approach a
miterd slip joint I need to do. He describes one on page 116 that
uses two through tenons. I'm going to vary it a little and use one
tenon but I think his approach will work just as well. Hope this
helps.
Richard Cline <[email protected]> wrote in message news:<[email protected]>...
> I would like to build some stretcher frames for painting. They use a
> complex miter joint at the corners. It looks like the joint would
> require a combination of bandsaw cutting and table saw cutting to high
> precision. It can best be described as a 45 degree section on the two
> top and bottom parts with two center parts making a lap joint.
>
> This is typically done on pine with a thickness of 1" to 1.5".
>
> Can anyone give me advice on the effective way to cut the joint?
>
> Dick
Richard Cline <[email protected]> wrote in message news:<[email protected]>...
> I would like to build some stretcher frames for painting. They use a
> complex miter joint at the corners. It looks like the joint would
> require a combination of bandsaw cutting and table saw cutting to high
> precision. It can best be described as a 45 degree section on the two
> top and bottom parts with two center parts making a lap joint.
>
> This is typically done on pine with a thickness of 1" to 1.5".
>
> Can anyone give me advice on the effective way to cut the joint?
>
> Dick
The plan would be to have a 1/4 inch tennon on a 1x3 inch slat/rail.
Mark the outside face of each rail. Start with a 1/4 inch dado blade.
Using a tennonning jig cut a slot with one side of the blade alligned
with the center of the rail. Test by turning the rail around in the
jig and making another pass. Adjust the jig until a very thin shaving
in the center is removed on the second pass. this will allow for a
left and right miter joint. cut all the lefts on one end and rights on
the other by facing the outside face to the left on one end and to the
right on the other. trim the 1/4 shoulder at a 45 degree on all
pieces. trim the 1/2 inch shoulder to 1/4 inch thickness at a 45
degrees to match the already trimmed shoulder. The thickness of the
triangular tab will determine the tightness of the joint.
I call these mortice and tennon miter joints, not sure if its the
right name.
Jack
George wrote:
>> You would be better off stretching/restretching the canvas with the
>> proper pliers.
>>
>> Miter sled/tenoning jig for the tablesaw will do 'em, but IIRC it's
>> six passes.
>>
>> "Richard Cline" <[email protected]> wrote in message
>> news:[email protected]...
>>>
>>> I would like to build some stretcher frames for painting. They use
>>> a complex miter joint at the corners. It looks like the joint would
>>> require a combination of bandsaw cutting and table saw cutting to
>>> high precision. It can best be described as a 45 degree section on
>>> the two top and bottom parts with two center parts making a lap
>>> joint.
>>>
>>> This is typically done on pine with a thickness of 1" to 1.5".
>>>
>>> Can anyone give me advice on the effective way to cut the joint?
>>>
>>> Dick
So are you looking at stretchers like these?
http://www.artsparx.com/store_canvasstretchers.asp
Josie
Richard Cline <[email protected]> wrote in news:dcline-
[email protected]:
>
> I would like to build some stretcher frames for painting. They use a
> complex miter joint at the corners. It looks like the joint would
> require a combination of bandsaw cutting and table saw cutting to high
> precision. It can best be described as a 45 degree section on the two
> top and bottom parts with two center parts making a lap joint.
>
> This is typically done on pine with a thickness of 1" to 1.5".
>
> Can anyone give me advice on the effective way to cut the joint?
>
Did you mean stock thickness or stock width? 1.5" is about the thickness
of a modern tubafor, and would make for a sturdy, but heavy stretcher
frame.
Is there a particular reason you couldn't use a lap or bridle joint, and
then reinforce the back with a triangular plate of 1/4" ply?
The reason for the lap miter is to make it somewhat self aligning, I
believe. More complexity than you likely want or need.
Patriarch
If you are going to cover the frame with canvas just make half lap
joints using the table saw. If more strength is needed, saddle joints
provide more glue surface area but for this you'll need to build a
table saw jig (unless you have a mortising jig.)
On Thu, 30 Sep 2004 20:00:12 -0700, Richard Cline <[email protected]>
wrote:
>
>I would like to build some stretcher frames for painting. They use a
>complex miter joint at the corners. It looks like the joint would
>require a combination of bandsaw cutting and table saw cutting to high
>precision. It can best be described as a 45 degree section on the two
>top and bottom parts with two center parts making a lap joint.
>
>This is typically done on pine with a thickness of 1" to 1.5".
>
>Can anyone give me advice on the effective way to cut the joint?
>
>Dick
In article <[email protected]>, Andy Dingley
<[email protected]> wrote:
Thanks for the detailed information. It looks like I need to fashion a
couple jigs and get serious.
Dick
>
> >If the canvas sags, it is
> >possible to install small wedges in the joint to tighten the canvas.
>
> No "if" about it - those wedges are an essential part of assembling
> the frame. Note also that the frame won't stay assembled unless it has
> canvas on it - there's nothing stopping the bars from falling
> outwards.
>
> The frame bar joints can be thought of as four parallel "sections".
> The outer two are a plain miter. The inner two are complementary
---------------
In article <[email protected]>, "firstjois"
<[email protected]> wrote:
Yes, that appears to be the type of stretcher I want. Unfortunately,
the photograph has the interesting joint at the far edge of the photo
so the detail is not visible. This is claimed to have a couple
desirable features. It is self aligning. If the canvas sags, it is
possible to install small wedges in the joint to tighten the canvas.
Dick
> So are you looking at stretchers like these?
>
> http://www.artsparx.com/store_canvasstretchers.asp
>
> Josie
>
>
On Thu, 30 Sep 2004 20:00:12 -0700, Richard Cline <[email protected]>
wrote:
>Can anyone give me advice on the effective way to cut the joint?
Big sliding MDF jig on the tablesaw. It's a pain to make, but once
you have it you can bang out frames at great speed.
--
Smert' spamionam
On Sat, 02 Oct 2004 16:48:41 -0700, Richard Cline <[email protected]>
wrote:
>If the canvas sags, it is
>possible to install small wedges in the joint to tighten the canvas.
No "if" about it - those wedges are an essential part of assembling
the frame. Note also that the frame won't stay assembled unless it has
canvas on it - there's nothing stopping the bars from falling
outwards.
The frame bar joints can be thought of as four parallel "sections".
The outer two are a plain miter. The inner two are complementary
halves of a half lap joint. However the inner edge isn't cut square
across the bar, they're cut at an angle (about 1 in 8, or maybe 1 in 6
for cheap canvas) and some way back from where they'd touch the other
bar. The gap is filled up by the wedges. Wedges are 1/4 the thickness
of the bars, and you always put them in in pairs.
I use two tablesaw jigs to make stretchers. Both are MDF "cradles",
sliding in the table's slots. They have a flat base, a sloping face at
right angles to the sawblade, some buttresses beneath and some stops
and guides.
Stock is prepared to a standard thickness of 3/4". Your jigs care
about the thickness, and the blade height cares about the width. You
really need a sawblade that cuts a kerf accurately 1/4 of the stock
thickness, which might be hard to find.
First step is to crosscut to length, using my everyday crosscut sled.
Second step is to cut the half-laps. Because these are handed, you
only need one jig. Make sure you cut the inside edge (always against
the face of the sled) on the same side at both ends! This jig has
the sloping face at the wedge angle, about 1 in 8 short of vertical
(83°). Two vertical (sic) rails form the lateral guides. The bottom
of these rails has a lengthwise stop across them (this gets sawn in
two on the first use). Side to side positioning is such that the kerf
goes through the second quarter of the stock. If your sawblade kerf
is too narrow, space the rails apart (by the difference between 1/4
stock thickness and the actual kerf) and use a couple of passes, with
the stock resting against each rail in turn.
Third step is to cut the mitres, in two passes. This uses a similar
sled, but with a 45° face and a pair of stop rails that are spaced far
enough apart to allow two positions for the stock - each cuts one
side. The end stop is the same as before.
For safety, put some toggle clamps onto the sleds. You're going to be
waving some long timber around and it's only supported at one end.
It's also useful to make a dedicated setting block for the sawblade
height. To keep the stock as low as possible for all passes, I saw at
two different blade heights.
Wedges are made from beech, bandsawn to thickness and quickly hand
planed to smooth them a little (optional). I saw them into a wedge
shape with a sliding jig on the bandsaw table, then stack them into a
pile and trim the ends by hand, eye and bandsaw.
Insert wedges with a hammer, not a mallet. You get better feedback as
to the sound changing if something bottoms. I like a square-headed
Japanese hammer for this job.
--
Smert' spamionam
On Sat, 02 Oct 2004 00:26:35 -0500, Prometheus
<[email protected]> wrote:
>On Thu, 30 Sep 2004 20:00:12 -0700, Richard Cline <[email protected]>
>wrote:
>
>>
>>I would like to build some stretcher frames for painting. They use a
>>complex miter joint at the corners. It looks like the joint would
>>require a combination of bandsaw cutting and table saw cutting to high
>>precision. It can best be described as a 45 degree section on the two
>>top and bottom parts with two center parts making a lap joint.
>>
>>This is typically done on pine with a thickness of 1" to 1.5".
>>
>>Can anyone give me advice on the effective way to cut the joint?
>
>That's done with a lock miter bit for your router or shaper.
Actually, I'd better clarify that last bit. I was looking at an ad in
Wood that was offering a bit called a lock miter, and it had a profile
almost identical to what you are describing. You'd have to use
something sort of like a tenoning jig to hold the board upright as you
cut, but it would be quicker than messing around with any kind of saw,
IMO.