# CNC Cut Portable Wortable



## MT Stringer (Aug 15, 2012)

I found a guy locally that could cut a work table top for me. Actually, he cut two out of the sheet of 3/4 mdf.

One of these is going with me to Oklahoma soon to do some work on our kids house they bought recently. :grin:

The dimensions are 32 x 48. The holes are 3/4 inch on 4 inch centers with a second row spaced at two inches.

I also had the guy cut a pair of hand holes so it will be easier to carry, and they work well.

First chance I get, I will run a round-over bit around the outside and all of the holes.

Then I plan to roll on several coats of clear finish to help prevent glue and spills from messing up this purty little thing.

I modified a pair of 2x4's to fit some saw horses like the guy did in this video. The top should fit it nicely.


----------



## tomp913 (Mar 7, 2014)

Looks good Mike. That's very close to the size I had planned for my cutting bench, can I ask how much you paid to have the holes drilled?


----------



## Gaffboat (Mar 11, 2012)

A nice looking and sized table top, Mike. I like the way the cross supports are cut to fit the saw horses. That should give you a convenient and solid work surface.


----------



## TenGees (Sep 12, 2012)

That looks very handy, Mike. I guess one could notch wooden horses to use the same set-up. I usually just put a piece of ply across horses to make a temporary bench - that would be much straighter and sturdier.


----------



## MT Stringer (Aug 15, 2012)

tomp913 said:


> Looks good Mike. That's very close to the size I had planned for my cutting bench, can I ask how much you paid to have the holes drilled?


$80.00USD.:grin:
I sent him my drawing and he drew it up in CAD. That was basically the charge.

I was there to watch the machine work. It's an EZRouter or something like that. Man, I would like to have one like that. No room for it, though.:frown:


----------



## RainMan 2.0 (May 6, 2014)

Those dang CNC guys are ruining it for us Mike :|


I'm liking that portable work bench , great idea


----------



## roofner (Aug 1, 2010)

How did you find your guy? By the way next week the Valu home center will be having sale next week on those saw horses for $25.


----------



## MT Stringer (Aug 15, 2012)

roofner said:


> How did you find your guy? By the way next week the Valu home center will be having sale next week on those saw horses for $25.


I made a post on a fishing forum I belong to asking about someone with a big CNC, and VOILA!, a guy that lives 18 miles from me (via freeway mostly) said he could do it.

Here is a picture. Dang it is bad quality.
He had just got started on the first one.


----------



## roofner (Aug 1, 2010)

Well now that you have 2 you could make any size you want. I just posted on the mft thread about buying an mft top and using it to make the size I want similar to shelf pin holes.


----------



## MT Stringer (Aug 15, 2012)

OK, So I got to thinking...what am I going to use to protect the surface of these mdf tops?

I heard water base poly was a no-no. :surprise: 
What about lacquer sprayed on the surface?
Shellac?

What I want to do is protect the surface from glue and paint or stain messing it up, if that is possible.


----------



## RainMan 2.0 (May 6, 2014)

MT Stringer said:


> OK, So I got to thinking...what am I going to use to protect the surface of these mdf tops?
> 
> I heard water base poly was a no-no. :surprise:
> What about lacquer sprayed on the surface?
> ...


 Glue on Arborite , then drill out the holes and route them out flush again ? 
I know , I always overthink things


----------



## honesttjohn (Feb 17, 2015)

Mike,

A couple coats of either shellac or laquer should do it. MDF already comes with a coating on it.


----------



## roofner (Aug 1, 2010)

Mike your tops are made of 3/4 mdf correct not medrite and you were planning on using a sealer to protect correct.


----------



## tomp913 (Mar 7, 2014)

MT Stringer said:


> OK, So I got to thinking...what am I going to use to protect the surface of these mdf tops?
> 
> I heard water base poly was a no-no. :surprise:
> What about lacquer sprayed on the surface?
> ...


Several coats of Bullseye shellac, sanding with fine paper between coats, finish with a buffed out coat of paste wax.


----------



## MT Stringer (Aug 15, 2012)

roofner said:


> Mike your tops are made of 3/4 mdf correct not medrite and you were planning on using a sealer to protect correct.


Yes sir.


----------



## MT Stringer (Aug 15, 2012)

tomp913 said:


> Several coats of Bullseye shellac, sanding with fine paper between coats, finish with a buffed out coat of paste wax.


Just took inventory. I have about 1/2 gallon of the Bulls Eye Shellac, and two partial cans of Deft lacquer.

I think I will save the lacquer for another job.

So Bulls Eye Shellac it is. Maybe today, but most likely, it will be tomorrow.


----------



## roofner (Aug 1, 2010)

I found a guy but his machine only has a bed of max 24 by 36 he has to do it in 2 passes . I will end up with 6ft by 2ft but I will leave the panel actual 3ft maybe even 40 inches width and from the off cut make a template to extend holes to full width of the panel. Hopefully the template will be accurate enough.


----------



## roofner (Aug 1, 2010)

Hey mike have you made any cuts with your tracksaw to see how well it works? Maybe I can get rid of my radial arm saw.


----------



## MT Stringer (Aug 15, 2012)

roofner said:


> Hey mike have you made any cuts with your tracksaw to see how well it works? Maybe I can get rid of my radial arm saw.


Not yet. I did lay out a 4 foot drywall square, and it is perfect.


----------



## MT Stringer (Aug 15, 2012)

@roofner

Just for you! :grin:

I scrounged up a piece of plywood for a test cut.

It looks like I need to refine my cutting technique. The dowels I used had a little play (not much but just a little). And they could have been longer. :surprise:

So, with the stuff I had on hand, I made a cut and it is off about 1/16th inch.

Tomorrow is going to be a busy day, so it may be next week before I can check things out.

One thing I noticed is my track has a lip on the outer edge. That may have been the culprit. Or, the holes may be off slightly. I hope not.


----------



## tomp913 (Mar 7, 2014)

@MT Stringer

I made a drawing and sent it to a local CNC shop - probably less than 10 miles from me - now waiting for a quote. I have been reading posts on Festool forums about hole size versus dog size and that led me to go ahead and order a set of the parf dogs from Lee Valley so I can have them match the holes to the dogs. In thinking though, it would seem that, within reason, a minor difference between the hole and dog shouldn't affect the accuracy as the dog will touch the hole at the tangent point and still have the plane of the dogs perpendicular to the other row of holes - assuming that the holes are all the same diameter.

A thought - a dowel is not necessarily round as there is different shrinkage with and across the grain so it could be a cause of some error. Just a thought.


----------



## roofner (Aug 1, 2010)

The difference in size is 20 millimeter which .787 inch 3/4 inch .75 difference is .037 inch . Close equivalent 1/32 is .03125 the 20 mm
holes are bigger by that amount. Parf dogs are bigger than Mikes 3/4 holes by that much. Closes equivalent is 25/32 in US size if you could find a 25/32 router bit it may work don't think they make that size.


----------



## tomp913 (Mar 7, 2014)

@roofner

I was thinking a difference just of thousandths rather than 1/32". On the Lee Valley site, the size of the Parf dog is given as 19.90 mm, and I read somewhere that the tolerance on that size is held to .0005" which is pretty tight. The site also states that the holes in the MFT are 20 mm which would give a clearance of 0.1 mm (.004") which seems reasonable - and the Parf drilling system comes with a 20 mm dia. forstner bit which would indicate that they're shooting for a nominal 20 m hole. Seneca Engineering has published a drawing of the MFT top which shows the hole size at 20.2 mm - this gives a nominal clearance with the Parf dog of 0.3 mm (.012") which I feel is starting to get a little sloppy. Hence the recommendation to provide the CNC shop with the dog that you are planning to use and let them cut some trial holes to establish the size needed.


----------



## roofner (Aug 1, 2010)

I had an idea for a substitute for parf dogs if you use 3/4 holes. Go to hardware sections of your home center find some 3/4 id by 1 od by 2 inch bushing using 3/4 inch bolt through the bushing then through your top with a flat wash and nut. The bushing were brass.


----------



## MT Stringer (Aug 15, 2012)

roofner said:


> I had an idea for a substitute for parf dogs if you use 3/4 holes. Go to hardware sections of your home center find some 3/4 id by 1 od by 2 inch bushing using 3/4 inch bolt through the bushing then through your top with a flat wash and nut. The bushing were brass.


For me, that might be a good choice. My 3/4 inch holes are exact and the dowels don't fit. But I do have four dogs made on the lathe by a friend. They fit snugly. Maybe a bolt would be an even better fit.


----------



## roofner (Aug 1, 2010)

That's my plan I have not setup the time yet to cut holes.


----------



## roofner (Aug 1, 2010)

By the way I did get a pair of the saw horse at Valu home Center for $25 on Sunday. The brand is stanley .


----------



## roofner (Aug 1, 2010)

Tom to drill your holes they need to be between .791 to .795 inches that gives your .004 tolerance. It is not a lose tolerance.


----------



## SteveMI (May 29, 2011)

I bought the DXF from MFSlab MultiFunction Slab Work Bench - Multi* Function* Slab for $18. I customized it with an opening to hold a router plate or other use. I plan to make an insert for my Kreg Pocket hole drill, vacuum hold and a vise.

I do not route or cut MDF due to the dust. I also wanted a table that wouldn't be junk after a liquid spill, rain, glue squeeze out or paint, so I chose to put Formica on 3/4" MDO before cutting holes. MDO may look like plywood, but is not. It is the material that outdoor sign makers use. 

Major lessons learned; put the MDO on the CNC properly the first time (notice extra holes on left) and test the diameter of your end mills. Picture tells full story of positioning the MDO. Even in the world of +$80 router bits do not expect you are buying NASA precision tooling. This project needs minimal clearance for a precise fit of the inserts and if your bit is 0.001" undersized, then the inserts won't fit. I already have Formica put on another piece of MDO and will cut it after more evaluation of this one.

My shop made (cobbled) router fence uses one of the holes to pivot on and a clamp to hold it in position. Has worked well for couple initial jobs.

After making the slab, I went about looking for gadgets to use on it. I bought some Bessey auto-adjust clamps from Lee Valley which are awesome. I plan to get some of the Parf dogs, wedge dogs and surface dogs. 

In hindsight, I saw that Rockler carries a lot of gadgets for 3/4" holes that I would like. I would advise people to look at those offerings before making the diameter decision.

Steve.


----------



## roofner (Aug 1, 2010)

For 3/4 holes bolt probably will not work because your hole would have to be .008 min bigger then the hole and no more than .012 bigger at the upper limit. The 3/4 inch router bit is probably very close to .75 inch


----------



## SteveMI (May 29, 2011)

roofner said:


> For 3/4 holes bolt probably will not work because your hole would have to be .008 min bigger then the hole and no more than .012 bigger at the upper limit. The 3/4 inch router bit is probably very close to .75 inch


One answer might be a 13/16" bit at 0.81". Freud and Whiteside make them. I didn't see it in a spiral right away.
https://www.amazon.com/Freud-12-162-16-Inch-Diameter-Straight/dp/B00004T7CT
https://www.amazon.com/Whiteside-Ro...coding=UTF8&psc=1&refRID=NHB7X0QZKRXWQR5S1HNT

Steve.


----------



## roofner (Aug 1, 2010)

This is the closes size bit The 13/16 .019 over upper limit This bit is .010 under low limit
https://www.amazon.com/Whiteside-Ro...coding=UTF8&psc=1&refRID=AT3XCGZAD8HB83XWYGRX


----------



## tomp913 (Mar 7, 2014)

@MT Stringer

Hey Mike,

While surfing Pinterest, I found this article on making a clamp for an MFT-style table that can be installed and removed from the top, no bottom access needed.

Making a MFT Clamp

Should be pretty easy to knock out a bunch of these, and at minimal cost too.


----------



## MT Stringer (Aug 15, 2012)

That looks pretty neat. Thanks


----------



## MT Stringer (Aug 15, 2012)

Well, when I asked for 3/4 inch holes, I got exactly that. My clamps won't fit through the holes. After a lot of soul searching, head scratching, and cussing (not), I came up with a plan to remedy the situation. (The guy even offered to cut a new table for just the cost of the mdf.)

Today, I pulled out my 4 inch hand grinder and got after the lower part of the shaft on a couple of the clamps. I got to thinking that only the first inch was binding, so I ground away some of the shaft diameter and worked on the radius of each one of them. And VOILA! It worked. They slip in and out of the holes with no problem. WHEW!


----------



## honesttjohn (Feb 17, 2015)

Don't 2nd guess the CNC computer!! It does what you tell it to do. Sometimes it just doesn't understand what you meant.


----------



## MT Stringer (Aug 15, 2012)

honesttjohn said:


> Don't 2nd guess the CNC computer!! It does what you tell it to do. Sometimes it just doesn't understand what you meant.


The holes are slightly less than 3/4 inch. None of my factory made bench dogs will fit. I have a set of Kreg dogs and they won't fit. Also, a couple of brass style with the spring to hold it in place. Nah, won't fit.

I was thinking about how I would ream the holes slightly, but now that these clamps fit, I am going to forget it. I still plan to run a 1/8th inch round-over bit around all of the holes on both sides.


----------



## MT Stringer (Aug 15, 2012)

If you have been following this thread, you may recall that I made a portable work station out of 2x4's and a couple of sawhorses. Today, the weather was outstanding, and I got to set up outside to break down the sheet goods.

My Keter portable workstation is just a little short so I had to shim it with some plywood. All in all, everything went smoothly. I had a sheet of 3/4 birch plywood and a sheet of Baltic Birch (for drawers).

We are planning a trip to Oklahoma next month so this was a good time to see how it all works together.


----------



## roofner (Aug 1, 2010)

Mike your kreg jig dogs are within .009 they must be a good fit. They would be on the low end of spec compared to holes in factory jig and the size of dog must be on the titer side .008 is min.


----------



## MT Stringer (Aug 15, 2012)

roofner said:


> Mike your kreg jig dogs are within .009 they must be a good fit. They would be on the low end of spec compared to holes in factory jig and the size of dog must be on the titer side .008 is min.


Yes sir. They are a tight fit. They will help hold the work piece in place and the clamps will work also, so all should be good.


----------



## roofner (Aug 1, 2010)

Did you protect your top yet? If so what did you use?


----------



## MT Stringer (Aug 15, 2012)

Two coats of clear finish - Parks Pro Finishes Poly.
Rust-Oleum Parks 1-gal. Crystal Clear Satin Water-Based Polyurethane-258690 - The Home Depot

So far, it has rejected the glue. Thank goodness.


----------



## roofner (Aug 1, 2010)

Mike another question the 2 x 4 used for bench supports if you make them flush with top horses you have lest than 50 % of material. I was thinking only 1.5 notch with tapered bottom. I have made notched grids that are inter locking and if dropped they break. I bought a 3/4 forester bit and drilled a hole with my drill press in 3/4 mdf took it to my home center and 3/4 bolts and 3/4 id x 1 od x 2 brass bush works just like a parf dog fits with no play with washer and nut.


----------



## MT Stringer (Aug 15, 2012)

roofner said:


> *Mike another question the 2 x 4 used for bench supports if you make them flush with top horses you have lest than 50 % of material. I was thinking only 1.5 notch with tapered bottom.* I have made notched grids that are inter locking and if dropped they break. I bought a 3/4 forester bit and drilled a hole with my drill press in 3/4 mdf took it to my home center and 3/4 bolts and 3/4 id x 1 od x 2 brass bush works just like a parf dog fits with no play with washer and nut.


I have been using the work bench with no problems while breaking down sheet goods. Since the notch in the 2x4 fits into the notch on the saw horse, downward force is spread through the saw horse legs to the ground. At least that is the way I see it.



> I bought a 3/4 forester bit and drilled a hole with my drill press in 3/4 mdf took it to my home center and 3/4 bolts and 3/4 id x 1 od x 2 brass bush works just like a parf dog fits with no play with washer and nut.


Hmmm...I don't think I have ever seen any grass bushings at my store. Probably wasn't looking for them. 

Do you have any pics of your set up?
Thanks


----------



## roofner (Aug 1, 2010)

Mike I will not be able to get back at the project until Wednesday. I will post pictures then . I may be able to show the concept earlier they only had 2 of the bushings and I wanted 4 they were going to get 2more from another store.


----------



## roofner (Aug 1, 2010)

*perf dogs*

Here are concept pictures. I was wrong there called 3/4 sleeve Barrings.


----------



## tomp913 (Mar 7, 2014)

MT Stringer said:


> For me, that might be a good choice. My 3/4 inch holes are exact and the dowels don't fit. But I do have four dogs made on the lathe by a friend. They fit snugly. Maybe a bolt would be an even better fit.


A standard 3/4" bolt has a body diameter allowable range of .750 - .741"; a bolt at minimum allowable size would probably be too loose in the hole to give accurate location. Also, brass/bronze bushings are typically oversize on the OD and ID - the bushing is pressed into a nominal hole to fix it in place, and this causes the ID to shrink to give the correct fit to the shaft. A bushing assembled on a bolt will be loose. and this will add to any clearance between the bolt and hole to allow the bushing OD - which is used as the locator on the table - to further misalign with the hole. You could possibly select bolts which are towards the maximum size - bearing in mind that you still need some minimal clearance between the bolt and hole so it can be installed - and then try to find a bushing that is about .001 tight on the bolt, heat it to expand the ID, drop it in the bolt and allow to cool and you have a zero clearance assembly.


----------



## roofner (Aug 1, 2010)

Tom they fit nice and will work if holes are drilled with cnc.


----------



## tomp913 (Mar 7, 2014)

@roofner

How much clearance do you estimate between the OD of the bolt thread and the hole ID and the OD of the bolt body and the ID of the bushing? - the OD of the bushing can be offset to the hole, in any random direction, by half the diametral clearance. For woodworking, it may not give enough error to be significant, but remember that the errors can be in both the X & Y axis so the total will affect the 90° angle between these axes.

If you look on the Rip Dog website, they address compensating for clearance between the dog and the hole before tightening down the clamp bolt (or nut in your case). This makes installing the dogs a little fussy, but should help to minimize any locational discrepancies.


----------



## MT Stringer (Aug 15, 2012)

roofner said:


> Here are concept pictures. I was wrong there called 3/4 sleeve Barrings.


Thanks for the pics. I think I am giving up. I will just keep using my track saw the old fashioned way...measure and cut. :frown:

Another thing I noticed. Why do those guys cut up their MFT's? They can be expensive to replace. I always use a piece (or pieces) of insulation board under the work piece so the blade doesn't damage the table.


----------



## tomp913 (Mar 7, 2014)

MT Stringer said:


> Another thing I noticed. Why do those guys cut up their MFT's? They can be expensive to replace. I always use a piece (or pieces) of insulation board under the work piece so the blade doesn't damage the table.


Yes they do, and some of them look to be pretty chewed up too. When I got rid of my 40 year old Craftsman radial arm saw, it still had the original particleboard top, but I lost count of the number of 1/4" Masonite tops I went through over the years. I've got a sheet of 1/4" MDF on top of my MFT (4 tabs of double-stick tape to hold it in position but easily moved), and thinking that I should get the same kind of life out of it. The saw is set to only cut 2mm into the 1/4" MDF so I figure that I can flip it 4 times (and maybe move it backward and forward a little too) before it has to be replaced.


----------



## roofner (Aug 1, 2010)

Mike I agree with what you have said. I am not planning on using a cnc to make the holes. Here is my plan I'm going to have my home center rip my 3/4 mdf. to 3 ft. by 8 cut 2 2.5 inch wide strips out of the cut off by 8ft. These strips would be lamenated to make instead of a cross cut sled a cross cut table using parf dog guide pins only 4 holes needed. Table will be 3 x 6 .


----------



## roofner (Aug 1, 2010)

*Radial arm replacement c utting table.*

Here is what I hope can replace my radial arm saw using my version of parf dogs. I am happy with my results so far have to make my 2 fences to finish . My cutting table is 3 ft x 6 ft can cut 30 inch wide stock using stop blocks.


----------



## MT Stringer (Aug 15, 2012)

I left my portable work table in Oklahoma at our kids new home. That way it will already be there next time we visit. So, I have bought new sawhorses and a couple of 2x4's to make a new set up. You may recall I have a second work top because the guy cut two of them from a single sheet of mdf.

Today I spent a little time in the shop piddling around. While I was at the store, I bought a 2x4 piece of mdf so I could make an extension. And that is what I did. I cut it to the same width of the work top (32 inches) and started routing the 3/4 inch holes. And then I got tired and quit for the day!

Gotta rest up. It's going to be a long day tomorrow at the crawfish boil! :surprise::grin::grin::grin:

Here's a few pics from the setup in Oklahoma and a couple from today. When I finish the table extension, I will be able to use it in the shop or the portable work table set up. The 2x's will be cut just shy of 68 inches so they fit in the bed of my truck. 32x68 will make a nice portable work area for sure.

Oh, I also upgraded the saw horses to the Stanley Fat Max model that has adjustable legs. That has already proved to be a Plus so I can level them with my work bench in the shop.

Onward and upward! :smile:


----------



## MT Stringer (Aug 15, 2012)

Worked on the portable table tops today. Finished rounding off all the holes, edges and hand holds on both sides. Then I rolled on two coats of Parks Pro Finishes semi gloss polyurethane.

Tomorrow, I will flip 'em over and coat the other side. They are looking good and should make for a nice portable work station.

Note: The guy that cut the top put a 3/8 inch radius on all four corners. I changed that to 3/4 inch. I like the look better. :grin:


----------



## MT Stringer (Aug 15, 2012)

Today I finished the portable workstation. All of the holes and edges have been rounded off and both pieces now have two coats of poly on each side.

I cut two 2x4's 68 inches in length so they will fit inside the bed of my truck. After cutting the notches for the saw horses, I did a test fit. It turned out just as I had planned. I have 32x74 inches of work space. That should work out well.

So, another project comes to a close. Hope you enjoyed following along.
Mike


----------



## DesertRatTom (Jul 3, 2012)

That portable work bench is perfect for my garage space. Easy to get out of the way, a couple of trusses to stiffen it, made as light as possible for easy lifting by an old guy. Big enough to lay some foam on it if I want. Let the ply overlap the long beams for clamping purposes. Really nice way to go. I think the folding saw horses are Stanley, which are pretty cheap. About 36 x 60 would be perfect, using 1/2 ply with trusses would lighten it up, 1x4 instead of 2x4 would help with weight as well.


----------



## roofner (Aug 1, 2010)

Mike since you now have a cnc have you thought of cutting a jig yourself to see if you could get better results?


----------



## MT Stringer (Aug 15, 2012)

roofner said:


> Mike since you now have a cnc have you thought of cutting a jig yourself to see if you could get better results?


If I make another one, I will give it a shot. I can cut up to 35 inches wide and how ever long it is needed. Normally, I can cut 22 inches long, but by using the "Tiling" feature in the software, I can set up the work piece so I can cut it in "sections". So theoretically, I can replace the larger piece 30x60 if I need to. Or anything smaller. It won't be as fast as the guys with the larger work areas, but that's OK. The guy that cut my original piece has a larger CNC, so he cut it all at once while I watched.  

I have been using the set up on my last project (kitchen cabinet remodel). Great to have a portable work table.


----------



## roofner (Aug 1, 2010)

My portable got rid of my radial arm saw and freed up space for me.


----------



## AshleyJ (Dec 1, 2017)

@Gary, a month later are you still happy with this as a radial arm saw replacement? Are your cuts as square? (Thinking about the photo Mike showed of an early cut that was about 1/8" out of square.) Did you use 3/4" holes and the bolt based dog you showed earlier in the thread? Anything you'd do different if you did it over?
@Mike, same question... anything you'd do differently if you did it over?

I'm debating 20mm vs. 3/4" holes, and I'm learning from your experience and ordering dogs _before_ cutting the top. Any other gotchas?


----------



## roofner (Aug 1, 2010)

It does work perfectly. I have been using for 3 or more months and sold my radial arm saw to a friend. Bought myself a 8 1/4 Makita 
to be able to cut 2 inch stock . Just got notice it shipped suppose to be here Tuesday. Cuts better than radial arm saw. The 3/4 bolts with 3/4 inch brass bushings.


----------



## roofner (Aug 1, 2010)

I am thinking of down sizing from the 6 ft. to 4 ft. with the back fence still 6 ft. Getting old the 6 ft. is heavy


----------

