If you cut it in half, you could cut a pocket that matches one of the shapes and cut a spline from a separate piece of wood. For instance, in your center frame piece you could cut a piece of 1/8" differently colored wood the same size and shape as the circle and T shape on top, then cut the design in half and remove 1/8" from the halves of the circle and T. Make the spline a design feature instead of a fix…
@RobertA_Rieke - So basically use an inlay to join the pieces? That’s a great idea! Thanks. Even if I didn’t want to expose it as a design feature, I could do similar on the back side with the same plywood. I could even design it as a stopped dovetail lap joint for added structural integrity. I like this direction…
By suggesting that you’ve forced my hand on leveling my wasteboard though, haha. I’ll have to have it leveled to cut the pockets.
I own Clayton’s Simplicity plans and definitely want to cut them out with an XC1000, so this topic is of great interest to me.
My first thought was to plunge through the thickness, to reduce tear-out on the back side, which you’ve done. You’re using a down-cut spiral, so the only thing I can think of is what about stabilizing the plywood with penetrating epoxy? This would turn your plywood into basically a piece of wood/plastic. It’s expensive, but would probably make your carving a slam-dunk.
I’ll be keeping an eye on this subject since Clayton was gracious enough to give me permission to use one of his gears in a “How To”.
Keep us posted, and good luck!
Chris
@NicholasKoza Nice work - looks like you’re working through your issues. I made a similar clock (Brian Law’s, Clock 22 http://www.woodenclocks.co.uk/page70.html).
Keep at it, there’s a lot of trial and error. I know I spent a few weeks making mine, although it was really the first thing I’d ever made on my machine.
It’s interesting reading the comments about speeds & feeds - unless I’m using a bit that needs a lower speed, I pretty much leave my DeWalt on maximum and simply adjust the feedrate. I get zero burning and with downcut bits (or sharp straight bits) I get nice clean cuts in ply.
My first version of my clock was cut mostly in ply, but I found there are some very low quality plywoods out there. Generally, I now use Grade A, hardwod marine ply. It’s a bit more expensive, but so is spending hours on a gear and then having a section of it fall out,
Cant wait to see some pictures…
A shot of mine the first time I got it running - so proud of it then. Looks a bit plain now…
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Hey, could you share your work flow in Fusion 360? So far I have not been able to get a usable drawing from the Deco drawings i upload to it. For example, using the trial version of CamBam i can open the drawing of a gear, convert it to polylines then join polylines. After that i can pick the profiles of the inside spokes, the center hole and the entire gear profile for machining. But in Fusion sometimes I can get the individual cutouts in between spokes to be selectable as one profile but the teeth are always 50 million surfaces and I cannot figure out how to join them within Fusion.
I have tried opening the drawing in Draftsight and converting to polylines and joining but when I upload to Fusion I still get way too many segments.
Don’t know if I explained my problem well enough but any help is appreciated. I love the all in one function of Fusion and the fact that it is free but I just can’t figure out how to make it work for me.
Thanks,
Stan
I starting using Estlcam partly for this reason. It loaded Clayton’s dxf files really easily. I haven’t cut any clock parts with it yet, I have only done dry runs, loading and preparing.
@DavidWestley - Thanks. This is the first big project I’ve done on my machine as well, so there’s a big learning curve. That gravity escapement is a thing of beauty. That’s a very nice looking clock that you’ve put together.
@StanPhillips - The only reason my workflow works at all is because I’m stubborn and pressed through a lot of manual work to fix up the plans, hah. Fusion360, as far as I can tell, doesn’t have a method for automatically closing the open splines.
Instead I imported the cut diagram into a sketch and proceeded to manually close up the splines. Basically I found that if I just wiggle the node a tiny bit it causes the spline to close up usually. In all reality it didn’t take terribly long to do. Most of the outside gear splines are usable as-is, thankfully, so that saves a ton of time (you shouldn’t need to close up each individual tooth.) The only gear spline I had to fix was the escapement.
From there, it was a matter of extruding the shapes, turning them into components, and positioning them for cutting, just like any other project at that point. This is the video that I keep referencing for that part.
@AngusMcleod - Easier said then done. The 500mm stock machine is going to be my machine for the foreseeable future.
@AlanWalls - I’m really interested in hearing how Estlcam ends up working out for you. I’ve not yet found CAM software that is both inexpensive and usable. Hence my weird workflow in Fusion360.
Edit - @MidnightMaker (that I somehow missed in my reply) - Yeah, I was trying to think of ways to stabilize it other than adjusting cutting settings. The idea I had was just applying some thick masking tape across the top. I’m not sure though that’d be worth the hassle. I picked up some more ply today and I’m going to give it a go at a lower speed. I’ve started to suspect that the little bit of chatter I was getting was part of the reason for the tear out, so I’m going to try a more conservative cut to reduce chatter.
Thanks Nicholas, guess I was just not patient enough. Your gears look great! Hope you get the frame worked out. Will be looking forward to seeing finished Deco.
@NicholasKoza Depending upon how you’ve set up your wasteboard, you can sometimes clamp things so the material sticks out the front and rear of the machine, allowing you to cut projects longer (or wider) than your machine.
Can you set up your jobs like this? You’ll need to be able to move the work and re-establish zero, however this isn’t an insurmountable problem.
@DavidWestley - I can have the material overhang the cutting area. I’m just not sure how I’d go about doing such a large multi-cut part. Right now I’m leaning towards the method of breaking it apart and putting it back together that Robert suggested above. If there’s a reasonable guide on doing multiple cuts on a large piece available though then I’d definitely weigh the option.
I am making a start at converting these drawings to V carve pro
if you are doing the same then we should collaberate.
I am gonna email the owner of the drawings to ask for permission to distribute my final notes
regards Neal
@NealRobinson
The Brian Law plans were simple to import into V Carve Pro. All I did was open the PDF version of the plans in VCarve and then adjust the material size to match the actual plan size. Delete all the bits you’re not cutting and then resize the material in V Carve to suit the remaining parts you’re cutting.
Sometimes had to use the “Edit. Select all Open Vectors” and then “Close Open Vectors” commands, but it’s pretty simple…
Yeah, I completely forgot about tape. I’ve had great success when taping the cut line on plywood when using a circular saw. Since you’re covering larger surface area, maybe contact paper.
did you complete any work on the Law clock because I downloaded the no. 2 clock PDF and didnt continue because some stuff wasnt to scale or had any dimensions to them.
The Randle clock WC5 is to scale or has enough info for me to safely continue. I live in Norway and dont have access to some of the hardware in the specifications, so I am adapting the plans for millimeter hardware. I am converting 1 page at a time and then cutting it out, its not material efficient, but it saves me getting bored.
My apologys to the thread starter for hijacking, if you want me to I can start a new thread.
regards Neal
@NealRobinson yes, I too had a few problems getting materials and I had to replace many measurements to suit what I could get.
Providing you keep the centre distances correct, it’s a simple matter to replace shafts and bearings. Most (possibly all) of Brian’s designs have measurements in both metric and imperial.
I also tweaked his design to make the clock run for 36 hours instead of having to wind it both in the mornings and at each night. Again, a pretty simple thing to do.
Can thoroughly recommend having a go at something like this. You’ll learn a huge amount about your machine and how to get it to do what you want.
Plywood is very susceptible to tear out especially if you are taking too deep of a cut. In this case 2mm is too deep. When I cut Birch plywood I set my cutting depth at .5mm per pass and my speed about 300-400. I rarely have tear out using these settings, the only time I have tear out is when I use the wrong bit for the job. What I did in the very beginning is I took the materials that I would be working with, the bits that I have on hand and I ran test cuts at various cutting feeds and speeds each individual bit. By the time I was finished I had documented well over 50 scenarios of what bits would give me the best results in the material that I was cutting.
Alright, an actual update. I got some time on the machine today and got a decent number of parts knocked out. Here’s what I have so far:
For the basic shapes I’m taking it at 650mm/m and 1.5mm depth per pass, and that works great. No tear out at all. On the intricate pieces (such as the wheels and pinions) I’ve pulled it back to 500mm/s and 1mm depth per pass. That seems to be working reasonably well. There’s still a tiny bit of tear out, but nothing like before:
That seems like a reasonable result to me. I don’t think the tiny bit of a tear out along the edge will affect the aesthetic or function of the clock once it’s actually assembled. I guess we’ll see. I could probably get it smoother by taking it slower and shallower, but as it is this is taking longer than I had initially expected.
And now for the “lessons learned” part of the story. When setting the home position, always make sure you take into account not just the width of the cutter but also the width of any pieces above the cutter. I narrowly avoided disaster:
I thought it was pretty funny that it looked like a tiny shark had taken a bite out of my clamp. The red is what remains of the plastic ring on the endmill.
Next up will be the frames and another attempt at the wheels.
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are you sure your not running a shark cnc in an x-carves clothing?
@NicholasKoza They’re all looking good.
The minimal tearout shouldn’t matter at all, but you will need to get the face of the teeth nice and smooth - particularly for the escapement gears. I ended up using a spray-on dry lube and a Dremel to polish them up - I used a narrow cylindrical stone bit (used for sharpening chainsaws I think) and cleaned each one individually (held in a vice and using an illuminated magnifying glass because I’m old…). The stone clogged up pretty quickly and provided a nice polishing effect without removing much material. You may get a little burning if you run the Dremel a little fast, but that’s usally not very visible. The bit I used just happened to be the same diameter as the gaps at the bottom of each tooth.
It looks like it wont be too long and you’ll be beginning to put it all together. Cannot wait to see how it looks and to see it running.