Clever! Didn’t even think of that.
Alternatively, I’m putting leveling feet on it when I’m upgrading, so I could see if I get enough angle adjustment there.
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I started with 12.5 degrees. I noticed, when cutting the last pass on 3/4” ply, the bottom of the sled would pull up when the sled was moving up. I bumped the angle out closer to 15 and that helped. The sled is 24.8 lbs. It may be that the linkage needs to be lowered a bit.
check how much height you need, leveling feet may not be enough.
David Lang
linkage too high sounds like the problem.
That will also make it tip more on the sides.
David Lang
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Woodcutter4, it worked great! Admittingly having a new baby stalled me from making a cut with it yet, but calibration worked and I can jog the full work area. You thinking of doing the same? I’ll let you know how accurate it is once i start cutting if so.
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Thanks for getting back to me! I have a 12’ top bar and I think that will have to be good enough for now 
I would love it if you could share a ton of pictures on here!
I’m going to build a new frame, once my METALMASLOW arrives here in Germany, with a profile similar to UNISTRUT and don’t mind to give the “large frame idea” a test … anything else I have to consider, to make it a real test scenario and can help the community to improve?
I don’t know how large you are talking about going, but one thing that we could
use testing on is different angles. in the past we had a little testing and know
that 20 degrees is to far from vertical (the sled sticks too much) and 5 degrees
is too close to vertical (when plunging, the sled moves away from the workpiece,
could be bit dependent)
does going closer to vertical let you go with higher feed rates, even in the
bottom corners?
David Lang
I designed the new frame to allow adjustments of the frame angle between 15 to 5 deg. …
our current tests tend to assume, that 11deg. is perfect… at least we could improve accuracy … our sled weight is about 12.5kg, motor distance 2952mm and distance to work area 505mm. The sled doesn’t tilt when its center reaches the edge of the working area by using bodybuilding weights of 2.5kg each. With bricks of same weight cog was different and sled tilting + its top never touched the working area…
Our new frame is currently planned to have a top bar of up to 3700mm and a total height of 2500mm with a adjustable skirting of 100mm around the work area…
Further we have planned to return back to bottom feed and introduce a chain tensioner using some springs, similar to barn door springs, but integrated in the hollow space of the top bar to achieve I.e. dust protection.
Budget for the above new frame is estimated with €250.
However, is there anything else you would recommend, or us to consider, so that the community can benefit?
I designed the new frame to allow adjustments of the frame angle between 15 to 5 deg. …
our current tests tend to assume, that 11deg. is perfect… at least we could improve accuracy … our sled weight is about 12.5kg, motor distance 2952mm and distance to work area 505mm. The sled doesn’t tilt when its center reaches the edge of the working area by using bodybuilding weights of 2.5kg each. With bricks of same weight cog was different and sled tilting + its top never touched the working area…
sorry, is this the result of testing? or where you plan to start testing?
Our new frame is currently planned to have a top bar of up to 3700mm and a total height of 2500mm with a adjustable skirting of 100mm around the work area…
could you experiment with the skirting? My belief is that no skirting on the top
is needed, the sides can use narrow skirting (50-100mm) and the bottom needs a
lot of skirting (150-200mm)
I would see how close you can cut to the edge without any skirting, then make
the skirting just a little wider than that.
Further we have planned to return back to bottom feed and introduce a chain
tensioner using some springs, similar to barn door springs, but integrated in
the hollow space of the top bar to achieve I.e. dust protection.
springs have the problem that they produce the most force when you need the
least, and the least when you need the most. weights provide a constant force.
If you want to make everything super slick, route the tension lines through the
tubes to weights in the legs (but it probably requires a lot of pulleys to do
that, having the lines just extend out past the workpiece and then drop down,
with pulley’s or just plumbing sweeps works well)
David Lang
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This is the data of the current frame we are using and our findings from testing by means of frame angle …
Currently we had been as close as 2cm to the bottom and top edge in the center area with good accuracy, but such is lost, once we are even 20cm off the left/right edge …
Thats why we decided to build a new frame with a top bar at least 3600mm and a frame height between 2250mm to 2500mm (skirting all around 100mm = 100mm bottom + 100mm top + 1250mm working area + >800mm distance to motors = > 2250mm …
Thank you for your advise … OK, we will experiment with some pulleys! 
Boris
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@buhlig How are your tests going with the larger frame? I’m very interested in your results.
Vielen dank,
-Jeff
Hey @JWoody18, we ordered the UA Profiles and accessories, which are expected to be received next week … keep you posted in due course! Bis dann …
Any updates on this? I am planning on building a 14’ top beam 30" above the work surface with a 10 degree tilt tomorrow. If that’s been done already, I would love to learn about it.
we successfuly upgraded to a 360cm top bar, 90cm above working area with a 11 deg tilt. first tests went fine. about to cut the first chair
Sweet! Let me know how it goes. I am building the new frame right now.
I misspoke before. I am going to be building a 14’ top bar, 28" above the work surface. Hoping this gives me optimal results, assuming I can get it to calibrate well.
Here is a 14’ top rail 28” above the work. I am routing the chain tenders via pulleys to the back side and using lead ingots in milk jugs as ballast. I haven’t run it yet, so there will be some tuning needed still.
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Looks great, how did the test runs go?
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