šŸŒž New Stock Frame Design šŸŒž

you have a point about the forward curve.
I donā€™t mind the plywood being a part of it because I put 4mm mdf on top as replaceable spoil board

Maslow S: Wood arms glued and screwed into the leg with top beam resting on the arms attached via two simple L-brackets.
Maslow SL: All features of S-model with unistrut arms and top beam for adjustability
Maslow SLE: All features of SL-model with rear plywood storage
Maslow SLT: All features of SLE-model with cup holders
Maslow GT: All unistrut construction

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:rofl: Now thatā€™s the version I want! Never underestimate the value of being able to drink a beer while the Maslow is cutting!

But what about a GLT version?

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I know from experience that you are going to end up cutting up the frame
plywood, not just your wasteboard

Clamp, or temporarily screw or nail the joint together before drilling the hole (and after double checking with your speed square :grinning:). Remove the afixing device(s) and install the bolt, or bolt first if youā€™d rather. Unless youā€™re way off itā€™ll stay in place

This is what the joint would look like as you are mounting the bracket to the leg (with the top beam moved back a lot so itā€™s balanced to not fall down.

I havenā€™t modeled the bolt holes in the bracket

this will be very square, and the unistrut to top beam will be very square, and the result is adjustable and easily reaches the distances we need with a 6" unistrut, and can be extended out to arbitrary distances by people who need more.

I am in the process of finishing up my new frame and was wondering why not install a 2x on either side of the front leg and then sandwich a one more 2x between them for more support, like the following in red.image

I wonder if there would not be too much chance of the strut being loose on the backside, I would think that you would have to notch the back as well as the front so that it could be tightned down @dlang image

ideally two bolts up a couple inches apart

with he gusseted brackets <$6 each, they really seem like the easiest, and most reliable way to make this joint.

two arms would be overkill, one is plenty strong

@Bar, have you looked at using your sled L-brackets instead of a stack of 2 x 4 pieces for mounting the top beam? I found that they worked pretty well.

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they donā€™t have enough of those l-brackets

how far out did you get the beam moved using them? you should have about 6" from the front of the leg to the front of the eam.

here is what it would look like with bolts.

Thatā€™s odd, I measure in the neighborhood of 4" from the front of the beam to the face of the 2x4 upright. That places the chains parallel to the workarea surface on my rig, with a 3/4" workarea and a 5mm spoil board.
Is 6" based on assumptions about sled thickness and linkage standoff height? Those are quite variable. I chose my standoff height to match the height that balanced my quadrilateral sled, seemed a reasonable choice. The sled thickness is part of that height because thatā€™s how I made the measurement, from the chain to the work surface. Iā€™ve put quite a few miles on the rig with this geometry, the chains seem to run smoothly.

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back around post 151 we had this discussion:

Bar did some calcuations and came up with a smaller number (forgetting the wasteboard and the material being cut) and we eventually ended up with a target number of just over 6 1/4" from the front of the leg to the chain. Iā€™ve been using 6" as a nice round number.

you are using a shorter spoilboard.

the weight of the bricks you use will affect what the proper balance point on your sled is.

This is why I am pushing the idea of the adjustability :smiley:

I believe that the original motor mounts put the motors out approximatly 6 inches from the front of the 2x4 (they were 8", right?)

Well,I did quite a lot of cutting all ready and didnā€™t go through it yet.
The z axis is accurate enough.

seems like there is no reason you should go through it unless an accident happens. And even then, if you are monitoring, then you could stop it fairly quickly

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when you have experimenters creating the g-code, itā€™s all to easy to make it go too deep, and while the maslow is slow, itā€™s not always obvious when you are too deep (and a lot of people are not going to be paying that much attention a long time into the cut). Getting a faster Z axis (which we should do), will just make it easier to have a problem.

Weā€™ve had people have their router pop loose and the bungee cord drive it to full depth into the wood and frame. We have a very primitive g-code parser that ignores codes it doesnā€™t understand, so if you have the wrong g-code, it can end up flipping the Y and Z axis, and try to go down deep into the material (and with the router we have, it will cut down like that)

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But things like that donā€™t happen on a daily basis and youā€™ll need a lot of those mistakes before you have to replace the 4x8

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Thatā€™s true, but weā€™re still designing the machine to support it. Itā€™s not that much more in stick lumber

also, some people are interested in using foam as wasteboard, and you need more thickness to be stable, being able to eliminate that 3/4" helps make room for it

I think that is the main factor here. People are going to do different things depending on their use cases. No one design is going to fit all, and this thread is trying to define what is necessary and how to accomplish that necessity in the easiest way possible. Everyone has put forth great ideas, and it is really difficult to parse those great ideas out into the best yet simplest design while still creating something that isnā€™t unduly temporary (and in need of immediate replacement).

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our goals

  • no temporary frame (which means no CNC cut parts)
  • very rigid relative positioning of the motors (top beam support)
  • able to be built with minimal tools (currently aiming at)
    • drill/driver with drill bits
    • tape measure
    • square of some sort (speed square is cheap and effective)
    • saw (including a hand saw)
    • wrenches/socket set (not a hard requirement yet, may be bits for the drill/driver)
    • pen/pencil to mark cuts
  • fit through a normal doorway (80" tall, 28" wide)
  • only include parts that you can get at a local lumberyard (everything else must be included in the kit)
  • work with the exiting motor mounts (since they have already been purchased)

we are trying to avoid critical angles or measurements, especially ones that must be marked and be the same in multiple places.

Where itā€™s important that two measurements should match, use a spacer to make sure the multiple instances are the same.

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