Here we have our general purpose die cutter, stencil, etching, marking machine.
By all marks a reliable, accurate, and best of all inexpensive piece of equipment. Pair it up with their Silhouette Studio Designer Edition, and you have a platform to go from CAD to anything that requires surface markup. We are constantly pushing the boundaries of what this machine can do.
Now, the machine only has one tiny flaw and it is strictly associated with how we are using it. No one (at least in their right mind) would be trying to create cut elements down to .001″ accuracy from a unit available from a craft store, but we are. To achieve this,the only part we had to modify was the deck hold downs.
The original design is beautiful and functional with a distinct usage pattern in mind. It was setup for the user to be able to quick change parts from the deck, simply undo the snaps and replace. Great concept, to be able to setup or work material while the unit is busy and then quick swap.
Where the quick swap gets us into trouble is the amount of play they require. Now while cutting a stencil of your name you won’t notice .050″ shift in the pattern, but an optical encoder will.
So this mod focuses replacing the snaps with hold down bolts. While we may lose some efficiency in the quick swap, we get a massive boost in accuracy when cutting small dimension structures.
First up we need to measure the build deck pad snap holes, and select an appropriate size of through bolt.
The build deck pad hole(s) measured 0.195″, so a #10 hex bolt at 0.180″ average shaft diameter gives us 0.015″ of play for mounting.
A 5/8th’s length bolt will give plenty of stock to work with for any size trimming required without excessive waste.
Next task is to drill the through holes into the deck that line up with the quick snap hold down posts.
Fortunately the hold down snaps are designed to be replaced, so we can make this mod and revert to the original configuration if desired.
With the snap hold down in place, strike alignment marks freehand with a sharpie or pencil. Given the free floating nature of the build boards, perfect hole alignment isn’t required…. but getting close helps.
Remove the hold down snap. Then use a straight edge to form a cross center mark based on your outside markings. This will be the drill point for the through bolts. Repeat this for all four hold down points.
Since plastic surfaces are slippery in general it is advisable to select a small drill bit to create a pilot hole. This will minimize “walking” when drilling the primary hole. Went one step further by using a spring loaded punch to dimple the center mark for the pilot hole.
Drill holes on all four marks and you’re ready to trim the bolts.
Insert only the upper left bolt, along with one build pad spacer. Lay a flat edge across the alignment post and against the side of the through bolt. Use a sharpie to mark where the flat meets the bolt, this will be trim height. Must be done to insure that all bolts clear the inside of the machine.
Measure and strike all four bolts for cutting to height. If you don’t want to trim things you can probably get away with 1/2″ length bolts to start, but has not been tested.
Using a machinist vice and hack saw, trim all four bolts to the strike marks. It is handy to put one nut on before cutting, so if threads get damaged you can back the nut off to straighten.
Last item is the head height of the bolts.
The two hold downs along the left side of the board are situated above a honeycomb structure. This provides excellent clearance for the stock bolt heads.
Unfortunately, beneath the right hand side of the board hold downs is where several motion components travel.
To fix this we need to shave the bolt heads to equal or less than the well depth. This conveniently is also the same thickness as the solid part of the quick snap hold down, so measuring is easy. The resulting bolt head should be 0.045″ +/- 0.005″.
If you don’t have access to a lathe of grinder, you can probably establish sufficient precision with just the two left hold down bolts and right quick snaps.
Mod is complete, tested for freedom of movement and ready for use.