# Two Piece Mill Vise



## devils4ever (Sep 13, 2020)

I'm looking at making a two piece mill vise to handle larger parts on my mini-mill (PM25) than I can't get in my Kurt vise.

I've seen a few designs. One design by This Old Tony that looks like it might be a bit large for my mini-mill and has more pieces to it, but seems very solid. I could probably scale it down a bit.

Another design that looks promising is by Blondihacks which is one piece, but doesn't seem it would be as solid and has limited range.

Neither design seems to offer a down force.

Harold Hall has some designs incorporated into a T-nut, but this design allows clamping in one direction (along the X axis). His designs do provide a down force which I like.

So, who has two piece mill vises and what do you like and dislike about them? Recommendations? Is a down force required?


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## cathead (Sep 13, 2020)

My machinist friend left me with two pair of these ERON sets.  Maybe the photos will help you fabricate some. 
These are pretty worn in the Acme thread area. 
	

		
			
		

		
	




The design might give some down pressure but I have not had an occasion to try them out yet.  
They are called ERON PV-1.


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## Diecutter (Sep 13, 2020)

Check out  MrPragmaticLee aka tin barn time, on U-tube.  He has a series of detailed and entertaining videos on the construction of a simple two piece vise  just the right size for a mid sized bench mill.  Don't forget a write up with pictures!


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## C-Bag (Sep 13, 2020)

I was thinking about a two piece vise like Rudy K but ended up getting a selection of TeCo toe clamps off eBay. They have served me well even though they were well used. But I got a huge range of them for less than what one new toe clamp would cost. By their design they are all down clamp. So much so they can easily mar the work. I like that not only is the jaw a “ramp”, but the slot that the table clamp bolt goes through is angled causing more downward force into the table as the jaw is tightened. Very handy.


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## devils4ever (Sep 13, 2020)

Thanks. I'll look into all these designs.


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## devils4ever (Sep 14, 2020)

C-Bag said:


> I was thinking about a two piece vise like Rudy K but ended up getting a selection of TeCo toe clamps off eBay.



Hmmm. I'm trying to find your reference to "Rudy K". Could you point me in the right direction?


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## C-Bag (Sep 14, 2020)

Rudy Kouhoupt. His vid on his shaper with his 2pc vise is one of the first ones on YouTube I watched on the shaper. It’s since been taken down .


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## MrWhoopee (Sep 14, 2020)

Here's mine. It began life as a vertical vise modification to a large angle plate, then revealed itself to also be a 2-piece table vise. I didn't really concern myself with down-force and have not encountered any problems with that issue. Parts clamped below the center line of the screw experience natural down-force due to the slight tilt of the moving jaw.


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## devils4ever (Sep 14, 2020)

Very nice design. I like it. 

What did you use for guide rods? They look like socket cap screws or is that drill rod?

What the approximate dimensions? Is that an Acme thread on the main screw?


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## MrWhoopee (Sep 14, 2020)

devils4ever said:


> Very nice design. I like it.
> What did you use for guide rods? They look like socket cap screws or is that drill rod?
> What the approximate dimensions? Is that an Acme thread on the main screw?


Thanks, it sort of took shape on the fly. The dimensions were dictated by the angle plate.
The guide rods are socket-head shoulder screws that I had on hand, running in bronze bushings.
The jaws are 1" thick, the fixed jaw is 3 x 7.25, the moving jaw is 2 x 6
Yes, that is a 1/2-10 Acme threaded rod.


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## devils4ever (Sep 16, 2020)

MrWhoopee said:


> Thanks, it sort of took shape on the fly. The dimensions were dictated by the angle plate.
> The guide rods are socket-head shoulder screws that I had on hand, running in bronze bushings.
> The jaws are 1" thick, the fixed jaw is 3 x 7.25, the moving jaw is 2 x 6
> Yes, that is a 1/2-10 Acme threaded rod.



I've been thinking about building this and a few things come to mind.

1. I might change the orientation of the jaws so the height is lower. This would make it a lower profile and give it more lateral support. For my smaller mill, I'm thinking 1.25" high and 1.5" wide closer to what This Old Tony did.
2. Is an Acme thread needed? I would love to try and make one, but it looks a little intimidating for the larger sizes. I would tap the hole and cut external thread on my lathe. Is 1/2-10 Acme doable with a tap? It looks like the forces are much higher for Acme threads vs 60 degree threads.
3. Are the guide rods threaded in or pressed in? I was thinking of using drill rod and pressing them into the jaw, but I need an arbor press.


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## dirty tools (Sep 16, 2020)

Great job


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## MrWhoopee (Sep 16, 2020)

devils4ever said:


> I've been thinking about building this and a few things come to mind.
> 
> 1. I might change the orientation of the jaws so the height is lower. This would make it a lower profile and give it more lateral support. For my smaller mill, I'm thinking 1.25" high and 1.5" wide closer to what This Old Tony did.
> 2. Is an Acme thread needed? I would love to try and make one, but it looks a little intimidating for the larger sizes. I would tap the hole and cut external thread on my lathe. Is 1/2-10 Acme doable with a tap? It looks like the forces are much higher for Acme threads vs 60 degree threads.
> 3. Are the guide rods threaded in or pressed in? I was thinking of using drill rod and pressing them into the jaw, but I need an arbor press.



Lower jaws would give more stability. When I was designing, I was thinking of standard (Kurt) height jaws, which was probably not necessary.

I used Acme threaded rod and nut that I bought from McMaster. 








						McMaster-Carr
					

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.




					www.mcmaster.com
				



The nut was turned round (not full cleanup) then pressed into a flat bottom hole in the jaw. The hole is flat bottom so the nut can't be pushed out under thrust.

The shoulder screws (guide rods) are threaded into the moving jaw. 








						McMaster-Carr
					

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.




					www.mcmaster.com
				



Unhardened drill rod is no harder than mild steel. Shoulder screws are equivalent to a Grade 8 bolt.


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## devils4ever (Sep 21, 2020)

While I'm waiting for supplies for the much larger version of this, I decided to make the blondihack's version. It seems pretty solid. I only wish I made the fingers a little thicker. This will be good for thinner material and light cuts.


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## MrWhoopee (Sep 21, 2020)

devils4ever said:


> While I'm waiting for supplies for the much larger version of this, I decided to make the blondihack's version. It seems pretty solid. I only wish I made the fingers a little thicker. This will be good for thinner material and light cuts.
> 
> View attachment 337802
> 
> ...



So cute!


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## devils4ever (Sep 30, 2020)

MrWhoopee said:


> Thanks, it sort of took shape on the fly. The dimensions were dictated by the angle plate.
> The guide rods are socket-head shoulder screws that I had on hand, running in bronze bushings.
> The jaws are 1" thick, the fixed jaw is 3 x 7.25, the moving jaw is 2 x 6
> Yes, that is a 1/2-10 Acme threaded rod.



Okay, I ready to start on this project. I was wondering if you milled any clearance under the moving jaw so it doesn't rub again the mill table when tightening? Maybe, 5 or 10 thou?

Also, the tricky part for me is aligning the guide rods so they are precise but do not bind. I was thinking of drilling the base piece and movable jaw together. For the guide rods, I'm using 0.375" drill rod and I bought reamers both under sized and over sized. I want to tap the drill rods into the movable jaw. Or, do I need a bushing of some type in the base?

My dimensions are 1.4" wide and 1.2" high for the base and fixed jaw and 1.2" square for the movable jaw.


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## MrWhoopee (Sep 30, 2020)

devils4ever said:


> Okay, I ready to start on this project. I was wondering if you milled any clearance under the moving jaw so it doesn't rub again the mill table when tightening? Maybe, 5 or 10 thou?
> 
> Also, the tricky part for me is aligning the guide rods so they are precise but do not bind. I was thinking of drilling the base piece and movable jaw together. For the guide rods, I'm using 0.375" drill rod and I bought reamers both under sized and over sized. I want to tap the drill rods into the movable jaw. Or, do I need a bushing of some type in the base?
> 
> My dimensions are 1.4" wide and 1.2" high for the base and fixed jaw and 1.2" square for the movable jaw.



I didn't leave any clearance under the moving jaw, I was more concerned about potential jaw tilt than about wear or drag. I would suggest making the guide rod holes with the parts stacked to assure alignment. Press fitting the guide rods in the moving jaw will give better location/alignment than tapped holes. Relying on a tapped hole for precise location is never a good idea. Since you are using drill rod, which is not particularly hard or wear resistant, I would recommend bronze bushings in the base.


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## devils4ever (Sep 30, 2020)

Hmmm. Okay. I don't have an arbor press, so pressing these in might be a challenge. I might have to get one.

I've never used a bronze bushing. Do they press in? Should it go across the full width (1.4")?


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## MrWhoopee (Sep 30, 2020)

devils4ever said:


> Hmmm. Okay. I don't have an arbor press, so pressing these in might be a challenge. I might have to get one.
> 
> I've never used a bronze bushing. Do they press in? Should it go across the full width (1.4")?


With a slightly under pilot on the end of the guide pin (and maybe some heat on the jaw) you should be able to drive the pins in. Or perhaps use a vise as a press?

Bronze bushings are designed to press into an on-size hole, then reamed to finish size. 








						McMaster-Carr
					

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.




					www.mcmaster.com


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## devils4ever (Oct 1, 2020)

What size arbor press would work for this? 2 ton? I think I'll have to get one.


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## MrWhoopee (Oct 1, 2020)

devils4ever said:


> What size arbor press would work for this? 2 ton? I think I'll have to get one.


Assuming  .0005 - .001 interference, even a 1-ton should do the job. Getting the pin started straight is the critical part.

With arbor presses, the limitation is frequently the vertical capacity under the ram. I'm currently struggling with this issue. A C broach (1/4-3/8) is 12 in. long, which stretches the capacity of a 3-ton press.

Far be it from me to discourage you from buying tools. Instead of buying a tool to do this job, try to imagine what your future needs might be and choose accordingly.


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## devils4ever (Oct 1, 2020)

Yeah, I've been looking at getting one anyways since I needed one a month ago to broach a keyway in a pulley. I made due with my large woodworking vise, but it wasn't easy. I see using this in the future, but not daily by any means.

Agreed that the vertical capacity is critical in this. I figured I needed at least 6-7" capacity for the broach. For this operation, I would need less.

All the 1 ton arbor presses I've looked at don't have the vertical capacity. That's why I'm looking at 1-1/2 and 2 ton models.

I can't find good reviews on arbor presses except for Dake which are $$$. I've looked at Jet, HHIP, Palmgren, Grizzly, Baileigh, etc.


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## C-Bag (Oct 1, 2020)

An arbor press for broaching and pressing in bushings is essential. After years of being on my list I found an old Jet #2 for $35. It has proven to be indispensable. When I ran out of height I remembered a trick from years ago and welded a plate foot to the bottom of some 3” pipe and set it under the table I have the press mounted to with some press plates on it. I had mounted the press with the end of it hanging off so long pieces could be pressed, so the pipe became the press anvil. I did a small weld to the the leg just in case. Not elegant but did the job. Ultimately I want to build heavy duty table for the press with stout legs that I can bolt knee type setup to. So far the arbor press only got stuck once and I have 12t hydraulic for that.


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## MrWhoopee (Oct 1, 2020)

C-Bag said:


> When I ran out of height I remembered a trick from years ago and welded a plate foot to the bottom of some 3” pipe and set it under the table I have the press mounted to with some press plates on it. I had mounted the press with the end of it hanging off so long pieces could be pressed, so the pipe became the press anvil. I did a small weld to the the leg just in case. Not elegant but did the job.



How about a picture or two?


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## C-Bag (Oct 1, 2020)

MrWhoopee said:


> How about a picture or two?


It was pretty ugly and I cut it back off when I was done. I don’t remember what I did with it but I’ll see if it’s out in the engineering pile


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## Larry$ (Oct 2, 2020)

I've been looking for at least a 3 ton arbor press so it has enough travel for C broaches. New ones are expensive and the shipping is a killer. In the mean time I've trued up my old 20 ton hydraulic press so it travels straighter. Way slower to use than an arbor press but I don't do a lot of broaching either. Since it's travel isn't perfectly true I push a little ways then slack off then repeat.  Press fits, pushing bearings & bending things makes the hydraulic press worth having.


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## vtcnc (Oct 2, 2020)

This thread is great looking forward to the finished product. Classic build a tool to make a tool to make a tool!


Sent from my iPhone using Tapatalk


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## devils4ever (Oct 2, 2020)

Here's the easy piece, the fixed jaw.


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## devils4ever (Oct 3, 2020)

More progress. I have everything done except the holes for the guide rods. I have to admit, I'm a little intimidated doing this last step after all the time I've put into this. So, I'm trying to determine the best way to drill these holes accurately. I want to stack them vertically and drill them at the same time to get better alignment. I trammed my mill. My vise is too shallow to put both in simultaneously. I'm thinking of doing it directly on the table. Alignment might take some time to get them directly on top of each other and aligned with the X and Y axis of the mill.

I decided to order an arbor press and went with the Interstate 2 ton model (#09511122) from MSC since it's reasonably priced and gets decent reviews. It has an 8-1/2" max work height and 1-5/8" ram. I'll have to buy or build a stand for it eventually. Shipping was a bit high.


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## devils4ever (Oct 6, 2020)

Okay, here's the setup I've come up with the accurately drill the two guide rods. I'm using two Kant-Twist clamps to hold the two pieces together and the vice to hold them accurately. Drill rod is 0.375" for guide rods.

My plan is:

Tram mill.
Spot drill both holes.
Use a 1/64" undersized (23/64") drill and go halfway into the bottom piece--movable jaw. (Do I need to go up in increments or go to the full size?)
Use a 1 thou undersized reamer to go through both pieces. This really only needs to be for the bottom piece, but it retains alignment.
Use a 1 thou oversized reamer and only go through the top piece--fixed base.
Remove and press drill rod into movable jaw.
Cross fingers it works!
Does this seem correct? Or, is there a better way? Maybe, I'm overthinking this, but I want this to work after the time and material I used to get this far.


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## Suzuki4evr (Oct 6, 2020)

vtcnc said:


> Classic build


It's a sickness I tell you......but one I can live with.


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## Papa Charlie (Oct 6, 2020)

If it were me, I would use something larger than 0.375" drill rod for my guides. If you look at the amount of meat inthe Kurt vice side guides that should give you an indication of the forces that you are trying to control. Especially when you might not have a work piece that goes the entire with of the jaws.

For the drilling operation, I would do it in steps. The first step, I would use a short drill which will serve as a guide for the following steps.

I think that your operational steps are just fine. I like the idea of running the first <0.001" reamer through both using the mill and then the final >0.001" reamer through the stationary piece, also using the mill to ensure alignment, without breaking them down. You may have to do some final clean up on the stationary piece but it keeps everything aligned for the majority of the work.


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## devils4ever (Oct 6, 2020)

Hmm. I'm all setup for 3/8" drill rod with the under and over sized reamers. Now, you got me thinking. 1/2"?

I do have 3/8" and 1/2" shoulder bolts which I understand is harder and stronger than drill rod.


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## Papa Charlie (Oct 6, 2020)

If I had a choice, I would go with 3/4" but you may be fine with the 1/2". Are the 1/2" bolts true enough to provide the alignment with the stationary part that they will be passing through? It may be worth the effort to validate and maybe even take a clean up pass on them to ensure they are as perfect as you can.

If you are going to use bolts, would you have them thread into the moveable jaw or just cut them off and press them in? If you thread them, you can always upgrade them if you need to much easier than if pressed.

I just have a tendency to over build things. Partly because I am not gentle at all. You can always make them larger if needed down the road.


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## devils4ever (Oct 7, 2020)

I may have to stay with 3/8" since the reamers for 1/2" and 3/4" are too long to get under my mill's Z-axis. I guess I could go with hand reamers if I had to, but they seem to cost twice as much.

Remember that this is for a PM25 mini-mill and I tend to take light cuts.

Is this the proper drilling sequence:

spot drill
drill 1/4" with screw machine length bit
drill with 1/4" jobber length bit
drill 23/64" screw machine length bit
drill with 23/64" jobber length bit


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## devils4ever (Oct 7, 2020)

It was mentioned earlier in this thread that I shouldn't rely on tapped holes for tight tolerances. So, I plan on doing a press fit.

If I use the shoulder bolts, I would cut off the threads and press them in.

Is there a way to remove a press-fitted rod? How would you pull it out?


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## Papa Charlie (Oct 7, 2020)

I should have asked the scale. For a mini I think you will be fine. Sorry to derail you.

Your sequence for drilling is fine. The final drill, 0.359 (23/64") might come out a little larger in the final hole. But given that by the numbers that should give you 0.016" (0.375"-0.359"=0.016") to ream out you should have enough extra to cover that. Clear chips often so that they don't enlarge or gouge the sides of the holes. Also, once you get into the first block with the last bit, you can double check what size you are ending up with before you go to far. Just in case you have to adjust sizes.

"Is this the proper drilling sequence:"

spot drill
drill 1/4" with screw machine length bit
drill with 1/4" jobber length bit
drill 23/64" screw machine length bit (If you have a gauge pin, good time to check final drill dimension)
drill with 23/64" jobber length bit
Ream small dimension through both pieces
Ream larger dimension through stationary piece


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## devils4ever (Oct 7, 2020)

Thanks. I don't have gauge pins, but I measured the drill rod to be 0.3751". That will have to be my gauge pin!

I have spiral flute chucking reamers so I shouldn't get much material in the bottom of the hole. 

What's the preferred method of using reamers? I've only used one once before. I understand you shouldn't peck, but go straight in and straight out? Also, don't dwell?


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## Papa Charlie (Oct 7, 2020)

I am no expert by any means, I pull often to clear the chips. Reamers, even fluted ones have a tendency to build up chips on the cutting points because we are generally removing very little material and without the larger chips, they don't seem to flow up the flutes. I have used straight reamers where this is compounded. 

I not only clear the reamer of chips, I make sure to blow out the hole as well to make sure I am not grinding the chips into the surface.

Lubrication is very important. I like the Anchor Lube as it is a heavy paste and stays in place as long as there isn't a high heat. But any good cutting oil like Tap Magic will do. 

Just take your time. You will be fine.


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## devils4ever (Oct 8, 2020)

Okay, holes have been drilled and reamed. Everything went pretty smoothly. I get a nice _pop _when I pull out the test guide rod!

I had some chips in the bottom of the holes when I was trying to ream them. I tried compressed air, but it didn't get them out. So, I used a long thin magnet and _*poof* _all the chips came out!

So, now I need to press the guide rods in. Should I keep the two pieces together or separate them? I like the idea of keeping them together for alignment, but I'm afraid it may bind if not perfectly aligned. Then, I'd be cooked and unable to separate them!

Thanks!!!


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## Papa Charlie (Oct 8, 2020)

Good job. Sounds like they came out perfect.

It shouldn't bind it at all unless you have the holes out of alignment. Either way should be fine. You can always test them by inserting a short way first to ensure you have your movement.

You could also ream out the moving block and use set screws to hold the rods in place.


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## devils4ever (Oct 9, 2020)

Success! The guide rods slide perfectly after pressing them in. No binding. It's like they were made for each other! 

This is probably one of the most precision set of parts I've made and I'm very pleased with the results. Thanks to all that responded and helped me!

I do notice the moving jaw seems to bind a bit when I tighten down on the fixed base. This makes sense since there is no clearance under the movable jaw. I may skim off 3-5 thou off the bottom so it doesn't hang up.


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## Papa Charlie (Oct 9, 2020)

Very nice job. I had thought you might have the moveable jaw out farther from the stationary, but now seeing how little that you will project out, the 3/8" drill rod should be perfect.

Removing a couple of thousands may reduce the binding you are describing. If you do, I would not remove much more than 0.001"- 0.002", as you want to support that jaw when under load. Remember everthing you remove will throw your part out by the same amount as you apply downward force from the cutting tool. It may also not give you as stable of a mount and enduce vibration and other issues. Frankly, I wouldn't remove any.

In fact, maybe a better solution would be to machine an oil groove the length (long dimension) of the bottom to provide lubrication. It would not require much to give you a small channel for the lubricant.


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## devils4ever (Oct 9, 2020)

Okay, I guess I'll leave it as.


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## Papa Charlie (Oct 9, 2020)

The end product looks very professional. My compliments on your work. Very nice.


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## devils4ever (Oct 9, 2020)

Thank you very much. I've learned tons in the few years I've starting machining in earnest and from this very friendly forum.


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## MrWhoopee (Oct 9, 2020)

Congrats, looks nice. A small tool that permits some large work.


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