Building 6" mini chop saw for small items....some modifications required.
Part 1 was
Out of the box-Observations,cause to modify..
Mics. Basic assemblage of grinder stand notes
The switch box Build switched rheostat speed control box
Rework 7/8" arbor flange Allowing use of 5/8" disks
6" guard Rework 4 1/2" guard to 6"
Vise 'equalizer' Simple bar to clamp short items and storage hook
Zero clearance insert Making table insert to better support material
Spindle wrench Thin wrench to lock spindle instead of the button
Part 2, this page addresses the vise
Temporary Add small bar that that engages deck ribs
Auxiliary vise screw Added additional screw and extended jaw to apply force at blade side of vise at 45°.
Upper vise jaw mount Replace undersized bolts and make one piece mount for upper vise jaw
Make deck extension, increasing material width/ size capability at an angle
After "refining" some of the simpler aspects of this small mini cut, continued with making a positive clamping screw for cutting at 45°. Then addressed the unbelievable slop in the upper vise and inability to fully tighten.
One thing I discovered is the limited material size that can be cut at an angle. What ever I decide to cut on this, it should be whether straight or angle, determined by size not angle. Piece of 3/4" flat bar just to show depth, rotating vise puts material at end of cut range and on the upward cut of blade.
Several ways this could be fixed, easy enough to allow larger material or centering on blade plunge is adding an extension to front of base. Re bolting the screw part of vise to it when needed. Haven't gotten around to it but that's the plan.
My original idea of redecking the base with say 1/4" plate, make couple of inches longer with a few pair of holes to locate vise where needed would have worked, still could.
Or had I seen this earlier, when I made the insert plate, I could have made it longer-T shaped
But if I address likely just bolt a length angle to end of base, again drill and tap a few pairs of holes to place screw end of vise where needed
But the real problem, even IF I relocate vise and material to be centered under blade when cutting at angle, increasing its material width capability...
Vise will not clamp material at 45°! So first solve is fixing inability to clamp.
Simply as shown all the force is at end of fixed jaw, over center. As vise is tightened just gets worse, as screw side 'slides' toward blade. Also force against end of fixed jaw overpowers screws that hold it in position. I can hold material so it doesn't rotate but in use blade is trying to pull material into it. I'm not holding with my hand. That's what the dang vise is for
The upper fixed jaw could have been manufactured at least an 1" longer. Tightening material would clamp instead of trying to rotate off end.
Though another problem that's then focused are the bolts holding upper vise jaw from rotating. A lot of force is exerted to the outer bolt(at scale) on fixed jaw to keep from rotating. Its nut is seated in the plastic pointer. Tightening when set at angle to stop rotation is going to break it. Worthless really so likely will removed.
Temporary fix to use saw....
Simple bar with piece that sets against ribs in deck, this 'stop' puts the force against the deck ribs instead of angle adjustment nuts.
Hokey but works for now, stops upper jaw from rotating. Also aids in setting up for 45°.
Auxiliary vise screw, Clamping at 45°
What I did. Other than material to be cut needs to be at least 4" or so long, the geometry is just all wrong. As pictured earlier, tightening vise it opens up at blade side, with a very small contact line clamping material. Part due to design of the little round pivot jaw. If it weren't hollow cast al, Id just put a bolt that would tighten in desired position so it doesn't rotate. Too simple. If both jaws were a little longer it would minimize how far jaw could spread. Because I want positive clamping I made another screw adjuster. It applies equal force to blade side of vice. Secondary stops rotating force. Between it and vise screw positive clamping along entire faces of vise jaws.
I've already done so not pictures of progress.
First I cut a full length piece of 1/2" flat bar to set against lower jaw, bent small lip that hooks jaw so cant be pulled into blade. To it I welded another piece of bent flat bar so screw will tighten on its flat and not at angle.
The clamping screw I used a 7" piece of 3/8" all thread. Welded 2 nuts to a short piece of flat bar that is bent over end of deck. Thru it is a 1/4-20 into base. 6-32 thru to into deck. Originally had the clamping screw butting against the flat bar boss but saw potential for it lifting. Drilled the hole and ground small nub on screw so they interlock
Works!
36" length held in vice! Pretty stoked, wasn't sure if this would really work.
Not planned but using the temporary angle stop bar gives me full support at blade end, but more stoked it extends past other end back so I could and likely will, make another 'equALizing' bar for cutting short material at an angle.
"Accessorized"
For a handel on the 45° screw I just screwed on a 3/8" threaded coupling nut with an acorn nut.
On the round to it, Making a new mount for the upper jaw, replace the undersized bolts. Currently 2 pieces. The plastic piece under angle bolt, and the square nut for undersized 'pivot' bolt. Between all that the slop, it could be anywhere from 40 to 50° with pointer at 45°, there's a good 10° potential. Most is in the pivot bolt which I'm changing to a 3/8" x 3/8" shoulder bolt. 3/8" shoulder blt is perfect fit for existing hole. Second is in the fit of square nut, just loose. When adjusting these fight each other binding.
Using 3/8" bolt thru angle slot, it will need minor cleanup to accept. The replacement clamp nut, will be one piece to accept both bolts, a glorified double T-nut. Also as the 3/8" bolts are closer to width of slot, when loosening to adjust jaw it isn't flopping all over. However 3/8" x 3/8" shouldered hex socket head drive bolts just not on most hardware shelves. That and fabbing the T-nut.
FYI- 3/8" shouldered bolt thru hole-If a person did nothing else, changing the pivot bolt dramatically improves slop, jaw actually pivots instead of slopping around? But 3/8" thread will need addressing
Whoo whoo! I found 3/8x3/8 shoulder bolts locally at Fastenall. I also picked up 2- 3/8x1/2 just incase as I'm not sure how this is going to be done. Both have 5/16-18 thread 1/2" in length.
Fastenall P/Ns (note local store didn't show single 3/8 x3/8 in stock #26326, but had them under the bulk p/n 1126326)
3/8" Shoulder x 1/2" Shoulder Length x 5/16"-18 x 1/2" lg Black Oxide Alloy Steel Socket Shoulder Bolt SKU: 26327 (SKU: 1126327) not used
3/8" Shoulder x 3/8" Shoulder Length x 5/16"-18 x 1/2" lg Black Oxide Alloy Steel Socket Shoulder Bolt SKU: 26326 (SKU: 1126326)
Though I had to clean up the slot the pivot hole was perfect.
Bonus is the heads are larger dia., was using washers under the metric cap screws cause they barley caught edges of holes.
Now to make a T nut. What occurred to me though instead is making a spacer that rides in slot to keep the bolts centered. Then a simple flat bar that sets against bottom of slot ribs that bolts thread into. Too easy. Plus it would travel in the cast iron slot a lot easier.
Cut a 1/2" thick piece of plastic to about 0.2 thick x 0.6 wide, just shy of 2 1/4" long. Used small flat file to scrap high spots on under side of cast slot. Drilled the plastic with 19/64" then again with 5/16". As its soft/thin this, though holes opened up, not to full 5/16" so they are snug on 5/16" bolts. Plastic is a bit thinner than depth of slot so doesn't get tightened against, only function is to guide/center the bolts.
Shown finished. I drilled the 1/8" x 1" x 2 1/2" lg flat bar for 5/16" tap. (Simpler would have been a thicker 1/4"+ piece of bar). Originally was going to drill thru holes as I'm welding nuts to flat bar, but threads of bolts would only engage by about 2 threads as I'm using the 3/8 shoulder bolts. The 1/2" shoulder bolts would have given more thread engagement but plastic would have been in the relief cut between threads and shoulder introducing slop. Simpler would be a 1/4- or better pice of flat bar
To center the nuts with tap holes I used an old tap- ran thru the nuts with tip protruding to center on hole in flat bat. Tacked nuts on then ran tap thru nut threading the flat bar That it worked amazed me, more that the holes aligned with holes in vise.
Guess I could have taken picture after finish welding & painting. But well worth the effort, loosening the screws I can adjust the angle incrementally from where ever its at. Before once screws loosened it was all over the map. I had left the flat bar under the plastic longer as I was going to weld a pin as a pointer. Now I'm not.
Several reasons, at 0° just rotating slot in jaw against 3/8" bolt- it is dead on square to blade. Second, would limit opening travel of jaw by 1/2" (which I gained by removing the factory pointer).
However mostly, any thing other that 0° (or 90° to blade) I'll be using a protractor to set. The 3° scale markings are off so indicator pointless. Don't know if it shows but the graduations from about 33 to 45° are scrunched and don't even point at pivot point? 0 to 30 close. Set up to cut at 45° using protractor, scale is reads about 43 1/2°? That and thinking in 3° increments...Just unsure how to remark the scale.
This is simply option to move materail down toward center of blade when cutting at angle
1/2" angle bolted to base with 2) 1/4-20 phillips screws. Drill and tap for the two 6mm vise cap screws. Was going to use 5/16", same as upper vise jaw, but a 5/16" allen also fits the 6mm more or less. Plus I dont think retapping the base for 5/16 good idea. So between the upper and lower vise halves still only one wrench needed for use and same bolts for either position.
The whole point...cutting wider material at 45°. I didnt gain as much as I thought due to pivot bolt of vise jaw hits bottom of slot. Minor opening of slot now allows 1 1/4", a bit more removal at slot end would give about another 1/2" of depth easily allowing 1 1/2" or better. Hesitant though removing more, completly removing raised edge thickness at bottom of slot. Likely as the boss for lower vise is close shouldnt be issue...then again. As I dont see really using this for that wide of material I'll hold off. Can always reset and double cut. Prior was 3/4" wide at 45° in single cut.
More effective, should I find the need, is remaking the lower jaw. Its junk anyway. Doesnt need to be 2 piece or bolted thru slot, face really could be wider...hmmm. Maybe later, all about options.
Second benifit of deck extension is I discovered when laying out, full width extension aids in support as its as tall as the ribs.
Notch extension for the secondary vise screw mount. Painted, reassemble.
The Kit. Actually entertaining -making it work. All materiall was cut using this saw. All said and done just another tool on the shelf. Mini saw. Perfect for cutting up small angle, tube and flat bar.
Back to Part 1 of the 'mini' cut saw
Back to Our shops tool mods section
