would it make sense to use a hollow core door (stable and flat) under spoilboard? i’m totally new to this but trying to understand what pieces i need.
most doors aren’t 4’ x 8’ but sure.
As long as you’ve got the chains/sled parallel to the sheet, the stiffer and flatter the structure (inclusive of any backing) the better.
it looks like you have the plywood clamped.
is that permanent? or is there a reason it should
be removable.
looks like a 4x8 door would be expensive. $270.
guessing that it’s not worth it since more brackets
or unistrut would flatten things out.
The thing that MUST be solid is the spacing between the motors, so any top-beam
design (especially if that beam is unistrut) is very desirable.
beyond that, you need the machine to not fall down, and if you are using thin
material, you don’t want to have it form into waves that are large enough that
it affects the depth of cut (because the sled happens to be on two peaks with a
valley under the bit)
The cheapest way to do this is to just use a sheet of plywood, and then put a
2x4 across the back of it to prevent bowing.
you could use a pair of hollow core doors, but if you cut too deep and hit them,
they are more expensive to replace than just a piece of plywood.
If you use doors, you will have to space out the motors a bit more to account
for their depth
David Lang
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got it. thanks! thinking that screwing unistrut to the back of plywood should do it.
My setup has a 3/4" piece of plywood with carriage bolts to the unistrut as part of the “frame” - after that point I have a spoil board and the workboard clamped to it.
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my machine is currently, um, ‘incomplete’ for a few reasons, mainly I’m unsatisfied with the vertical linkage kit’s chain attachment points.
I have no simple method for decoupling the sled yet. Considering moving to a Ring…
The hanging point seen in some picts above is not a good solution.
Additionally, my Aux1 pins are operating the opposite of as intended, but thats another thread.
Aux4 remains untested.
Back to the frame, Yes, my design above needs additional main work area stiffening, better clearance for the sled on the bottom of the frame.
I’ve been thinking things through while its been deadly cold here and should write up some more on this soonish.
good luck!
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what I’m doing now is sending out links like these:
https://www.ebay.com/itm/Qty10-25-Offset-LINKS-FOR-25-ROLLER-CHAIN-25-ROLLER-CHAIN-Cheater-LINKS
with the idea that you can use a pin like the maslow came with to hold these to
the linkage.
I purchased some like these
https://www.pivotpins.com/products/bs-hair-pin-cotters.html?filter=wire_diameter_in%3A2%3A0.091
and am sending them out, but while they fit through the linkage well, the don’t
fit through the half-links, so I may need to order some thiner ones.
I’m looking at getting some of the center brackets made and starting to send
them out to people who have the earlier kits, when I do that, I’ll add the half
links and pins as well.
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yeah, I tried that with some SS pins but the sizing wasn’t quite right, a 32nd off IIRC.
I do not like 2x $8 chain links, just on principle.
I have some more wiring/testing to do on Aux1 and Aux4. and Stiffening to work on. I’m gonna get those together 1st, before moving to a permanent sled, at which point sled design will be back on the table.
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I found them from US suppliers for ~$1 each, and from china for about half that.
The other thought I had (but haven’t tested) is to punch out the pin from the
chain so that you have two side plates at the end, no expensive links at all
(but surgury of the chain needed)
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I’ve considered a pipe across the top. I however I have not experienced any flex on mine, I added 2 x4’s in a simi X pattern to stiffen my plywood.
Thank you
I am planning to do the unistrut design and I was wondering if you can go straight to the unistrut frame or do you have to build the temporary one first.
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I don’t believe you have to start with the temporary frame, but…
My understanding is (and I could be way wrong here) that the temporary frame is intended to allow one to make certain components of the permanent frame more accurately. If you already have the means to make those parts or make a frame accurately enough, I believe you can jump right ahead.
I’m on the February delivery list, so I’m totally not speaking from experience.
A percentage of my frame will be unistrut. I’m not totally sure what that percentage will be, and it may change over time. At the moment I’m sure the top rail and the upright posts the rail and plywood backer make contact with will be unistrut.
Over time, I’d like to try to move in the direction of a completely CNC plywood frame - not unlike wikihouse (or similar) components. Because CNC routing plywood is why I’m getting into a Maslow anyway. To have my Maslow improve my Maslow sounds like fun.
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I went straight to the unistrut frame with a hand cut sled, the using that to cut my ‘real’ sled (mostly for esthetics… the hand cut works fine)
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go straight to the final frame.
The temporary frame is to allow you to cut out the plywood parts to hold your
final frame together (the gussets and wing shapes), when you aren’t using those,
there’s no need to do a temporary frame.
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did you get the unistrut cut where you purchased it?
I used a hacksaw and it cut pretty fast.
I cut it myself… metal cutting blade in my jigsaw (it’s tough stuff though… ate a couple of blades)
A rotary grinder with a metal cutting wheel will chew through the unistrut pretty quickly.
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thanks. our local electrical supply where we bought the unistrut cut it for us.