Larger sled to cut larger pockets?

Hi, I would like to cut big pockets up to 1 meter. I imagine I can do it if I build a larger sled to keep support while I keep the same dimensions for chain fixings. I have not got a Maslow at this time, so it is difficult to figure it out. Your opinions are welcome please.

Hi there and welcome, The larger you make the sled, the more you have to deal with friction. I would not exclude that it’s possible with a special no friction sled, but 1m pocket would require a sled with min 1.02 radius. That is a huge and heavy thing. It depends on what it is made of.
Edit: If the pockets are not that high, a smaller sled will work.

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I wonder whether if you could arrange to cut the pockets from the center, or in separate connected sections, you could pause and put in a piece of something as a filler to support the sled?

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In spirals from in to out is a great solution. FreeCAD does spiral pockets. Don’t know about other software.
Edit: But I guess you would have to divide the path to full depth in steps.

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@lalebarde

Welcome to our group. I would suggest seeing it you could make a series of connected cuts that end with the shape you are looking for. Do you have a visual example of what you are doing?

Thank you

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You might be able to reduce weight and friction by making holes in the sled. A swiss cheese sled, as it were. Since the pockets would be so large, you could skeletonize the sled pretty extremely.

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@Bee, my concern is blind pockets. I retain two solutions : the @Keith 's swiss cheese sled, and if necessary the @blurfl 's connected pockets with hand finitions to sand down the connections. Thanks all of you :grin:

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If your finished piece could be accomplished by gluing up two (or more) layers, maybe you could make the pockets by cutting out the pocket shape from a sheet of stock, leaving the middle attached by tabs so the router would remain supported, then remove the waste piece from inside the pocket outline by cutting the tabs, and laminate that onto the back sheet.
That would leave the waste piece as usable material, instead of chips…

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you can reduce friction by angling the machine closer to vertical.

This is an area of experimentation, so we don’t know how close to vertical you
can get.

In the meantime, cut around the outside of the pocket, and then go back and
forth from the top to the bottom the sled will always be supported

David Lang

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From what I see with all triangular kits is, we have a shifting ‘pressure point’ on the sled, CG.
Depending on the position on the sheet the chains are highest if the sled is at the bottom, pressure on the brick side and if you move to the top and the chains get close to horizontal with the bit, the pressure is on the top of the sled. This effect increases with steepness. The reason why I could run 6° with brackets but with triangular need 8° or more to keep the sled flat.

If you have trouble keepting the sled flat, that has to do with the height of
the chains above the sled.

David Lang

It could also be adjusted by raising the weights above the sled to shift the center of gravity. That might be easier than re-making the linkage mounts.

With all triangular kits the GC shifts up or down with the position on the sheet. With brackets there was a balanced sled all over and the CG did not change.
The closer you go to vertical with the frame, the harsher this change of CG will effect you. I’m only sharing my observations, with no claim that that they are true.

I think we must be talking about different CG.

If we are talking about the sled tilting away from the workpiece, we should be
talking about the CG along the Z axis

this should not change based on where it is on the work area.

the CG in the XY plane will change compared to the ends of the chains as it
moves around, but that shouldn’t cause it to tilt away from the workpiece.

It’s hard for me to follow tonight, after testing 1.09, being drunk (Do not operate power tools under the influence of toxins!)
I will continue to learn if

does not change between the 2 pics, after the second coffee in the morning.

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Could you provide a link to the brackets version please ?

Sorry, I don’t get the question right now.
You mean the setting in the software?
Or on the sled? In my archives I found this:

@Gero , I have edited my question to add the full quote of your post

Sorry that I still don’t get it. Sitting on my brain I guess or it is the after work beer.
The black brackets on the picture with the the 6 holes existed only in one version, as I remember.
In the software you choose either Quadrilateral for brackets, or Triangular, for one of the triangular kits ( ~4 built and 3 up for sale).
If the triangular kits can be considered as the successors of brackets is challenged by results from Maslowians cutting amazing things with the original chain mount system.
The math for triangular has become much less a headache, then calculating how much the bracket sled tilts at certain locations.

I can provide a link to the brackets, a killer deal from my perspective. If they werent so heavy I would order a dozen. http://www.maslowcnc.com/store/chain-bracket-l-bracket
It’s the ‘bracket version’ in the question, that I don’t get.

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