Looking for temporary use of a zero clearance throat plate for 3D modeling

[jlmeredith]

I have uploaded this first version for others to take a look at or print if they would like. This does not account for several changes listed in my last comment:

https://thangs.com/designer/jlmeredi...urce=All+Files

[jlmeredith]

I thought others might appreciate seeing the iterations that I have been through to get to this point.

Today, I will print a new version that will account for the arbor/washer cut outs in the full height position as well as adding some additional support ribbing in the areas where the blade does not pass up through or interfere with the plate.

I think I will also need to make a small additional change to address the blade assembly on the back side of the saw making sure that there is not a collision point where the carriage assembly moves up toward the plate.

LCHIEN - I will be adding a version with a cut out for the factory splitter and I think because this is 3D printed, I can make it so that there is more support there hopefully. Like I indicated though above, I am also making a version that will have holes for the Microjig Splitter. I will be sure you get a couple of these when they are completed! Thank you for your encouragement and feedback/help!

This is just a photo of several iterations where you can see the progression of my work. Starting on the right, I modeled the insert for size, then adjustments for holes and thickness, then the version that had some print issues when making the deeper version, then the final version that I have confirmed clears the blade and arbor assembly.

[LCHIEN]

Very Cool! I see a lot of thinking has gone into this. More thinking than I have done. Good job!
I also like the idea that you hollowed out the underside some. I know that reduces material use and solves the jamming the blade and washers problem. But that you kept a lip around the area to stiffen the whole plate.

My ZCTP has suffered a lot of abuse through the years and I have thought about replacing it.
The three hole pattern as I suggested is in thin material and the use of countersunk flat head screws has made overzealous tightening break out the edges.
The poor plate has been jammed on much more than one occasion by attempting to bevel tilt the blade without changing to the metal OEM throat plate only to hear all the parts screaming in protest and the poor plate twisting in ways it was not meant to.
Finally, and I don't think there's much you can do about this, is that the thin portion at the back has cracked where the cut has been made all the way back to accommodate the riving knife. I can't think of any way to reinforce that part which is like .080 thick and about half an inch wide. Of course the original OEM metal throat plate is split in this area so maybe its not a big deal.

I sure would be happy to see that I could get a couple of printed blanks. Thank you for sharing.

[jlmeredith]

How about an interlocking joint like jigsaw puzzle? Overlapping perhaps for vertical alignment.

I am using a simple dovetail for the prototyping right now, but long term, I will use a scarf joint that will will ensure a perfectly flat surface for those that opt for printing in two pieces. I may also make a version that has just the blade cut out portion removable. This would allow one to print a solid outer section and then change out the Zero Clearance portion apart from the frame.

[jlmeredith]

This is the photo I am using to model the lower portion of the plate since I have not been able to secure a sample. I will do my best to create the same structure in the final part.



Here is the current state. I will add some cut outs for the arbor and add in the ribbing to give the plate more mass. I will also be generating a version that has holes pre-placed for a Microjig Splitter attachment.

Getting there!

[LCHIEN]

... what kind of joint I should use for joining the two pieces when split in two.

How about an interlocking joint like jigsaw puzzle? Overlapping perhaps for vertical alignment.

[jlmeredith]

You are correct and ideally printing as one piece will be ideal, but I think that given the way I am designing the joint and associated connection with the base, printing in two pieces will work as well and they can be joined with some quick set resin or even good ol superglue. I should have a tested design by this weekend.

[jlmeredith]

Yes, I am designing this to work with the 4 hole pattern as this is the original design of the ZCTP. The holes will be solid from top to bottom to ensure a solid connection. I am currently working through mirroring the lower portion of the original as best I can from photos. It is a time consuming process though given the way that the original was injection molded.

[dbhost]

I have the initial modeling completed. Now time to print and test fit. Once I have the test fit completed, I will add chamfers and some of the lower cut outs and then determine what kind of joint I should use for joining the two pieces when split in two.

Just FWIW, many of the newer affordable printers can handle the print in one piece. I have a Voxelab Aquila X3 Max with a 400x400x400 build volume. 14.25" is something like 360mm, so within the build plate. I believe Creality has a couple of models this large as well. I know not as common as the typical 220x220x250....

[LCHIEN]

Last question...

There are two sets of mounting holes... the four holes (B) and three hole pattern (A) (the latter used in the OEM ZCTP blanks)

Are you including both sets of holes? My ZCTP is "wearing out". The ZCTP is very thin at the ends where the 3-hole pattern lands. The fact that it has to be countersunk for flat head screws makes it even thinner and its a weak point if you torque the screw down hard, the chamfer tends to make the hole want to break out of the near edges.

Having the option to use the four hole pattern, would be an advantage because the holes are about 15/16" or one inch away from the edge and the ZCTP is much thicker there... at least 11/32" thick rather than 0.080" where the three hole pattern lands.

Having the option of using the 4-hole would be good. One option is to put the hole as a closed end hole from the top of bottom that the user could drill out to use. It would need a chamfer countersink on the top.

[jlmeredith]

LCHIEN d_meister - Yes, I am modeling it so that there are very similar structures on the bottom of the plates as was provided in the factory plate. I unfortunately had to travel this week and have not been able to circle back on things yet. I will update with additional renders as they are ready.

[d_meister]

There should also be an arced relief for the arbor washers at full height of the blade.

[LCHIEN]

Did you model the recess on the bottom so that a new plate does not jam the blade and break the belts?

There is an arc-shaped recess molded into the bottom of the OEM plastic ZCTPs to clear the blade even at its lowest position as a straight bottom would trap the blade when screwed down.

I recall that people who replicated the plate with no recess broke belts. To use them they had to lower the plate into position on a spinning blade, a kind of *shudder* scary operation. Or the other option was to use a 7-1/2" circular saw blade or a single side dado blade to start making the slot enough to put in a 10" blade.

[jlmeredith]

I have the initial modeling completed. Now time to print and test fit. Once I have the test fit completed, I will add chamfers and some of the lower cut outs and then determine what kind of joint I should use for joining the two pieces when split in two.

[jlmeredith]

d_meister - Yeah, I need to figure out where the signature is actually setup. That is my old trim and cab business.

dbhost - I will post the design for both a split version and full size version.