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laura vianello
01-03-2018, 2:28 PM
Hello Forum,
Is there anybody who would be able to CNC a table top (Baltic Birch) with 20mm bench dog holes (like MFT top)? Anybody who has gone this route? Any reputable CNC services company in MA? The table top should be 2x5. Thanks

Jim Becker
01-03-2018, 4:57 PM
It's easy to make a jig to make these tops accurately yourself with a router. Watch Timothy Wilmot's bench video on YouTube...a simple tee-square with 30mm holes spaced at 96mm increments down the centerline for a 30mm guide bushing and the "tee" being the exact width to put the centerline from the previous row exactly 96mm over for the next row. You set it up to start 77mm from the corner in both directions. A 20mm router bit is relatively inexpensive, too.

Brad Shipton
01-03-2018, 6:15 PM
For a one off you might find someone reasonable at: https://100kgarages.com/ Anyone with a CNC can cut that if you give them a DXF file. The trick is finding someone willing to do it near you. It would be about 10-30min of machine time depending on what machine they have so there is not a lot of money in it for them.

Brian W Evans
01-03-2018, 6:59 PM
There are a few jigs out there that help you drill or rout those holes. I thought Woodpeckers had one but I couldn't find it on their site. Lee Valley has one of their own (http://www.leevalley.com/us/wood/page.aspx?p=72602&cat=1,41637)and also carries one called the Parf System (http://www.leevalley.com/us/wood/page.aspx?p=75354&cat=1,41637).

If you want one CNC'd, the only recommendation I can make is in CT - Parkerville Wood Products (http://parkervillewoodproducts.com/) near Hartford.

Good luck.

Ralph Okonieski
01-03-2018, 7:07 PM
Another fairly low cost jig is by Woodrave. I bought one to make several Christmas presents. Worked very well.

no affiliation with them, just a customer.

http://woodrave.blogspot.com/p/blog-page.html

Jim Dwight
01-03-2018, 7:17 PM
I will also report favorable results for the Woodrave jig. I did not expect the holes to be square enough to use for a squaring jig but they are. I used HD pegboard that didn't seem all that accurate. I think the secret if the pegboard has inaccuracies but over the 8 feet length, not the shorter lengths I am typically measuring and building. I don't have an 8 foot square. All my squares say the holes are square.

Mark Carlson
01-03-2018, 8:40 PM
I'd buy a MFT top from festool and use it as a template to route out the holes with a 20mm router bit. Then use 20mm parf dogs to index the top to the next set of holes.

Ted Derryberry
01-04-2018, 9:18 AM
Word of warning, CNC machines can be "out of square", especially the bolt together ones. I have an older ShopBot and it's out maybe 1/16" in 4'. Not enough to matter for what I use it for so I haven't gotten around to squaring it up. Just don't assume that because it's drilled on a CNC that the rows and columns of holes are square to each other, especially if somebody with a hobby level machine does the job for you.

Frankie Hunt
01-04-2018, 10:03 AM
There are a few jigs out there that help you drill or rout those holes. I thought Woodpeckers had one but I couldn't find it on their site.
Good luck.

The woodpeckers kit was a "one time tool" offering.

https://www.woodpeck.com/hole-boring-jig.html

Bob Vallaster
01-04-2018, 11:46 AM
Laura, thanks for raising this topic. I want to do a similar project.

To Frank and Brian, the Woodpeckers one-time-tool deadline passed in November; deliveries to commence in February. Made me think, "no harm in asking...". I just visited the link above (works dandy), called them, and placed an order.

I'm a happy camper.

BobV

Ben Abate
01-04-2018, 11:48 AM
I would suggest going over to the FOG Festool site and do a search. There is a lengthy discussion on how to do it your self with CNC accuracy. Peter Parniff from the UK along with Axminster Tools offer a set up that has gotten great reviews.

I went the CNC route and had a fellow I knew make my top. It took a few times for him to get it to my specs. A lot of time and money. If you go the CNC route find a reputable person and find out who pays for the mistakes. Also there will most likely be a setup and a charge for doing the programming. Some things you may have not thought of

take care

Ted Derryberry
01-04-2018, 12:24 PM
Another thing about CNC is the operator might be tempted to use a smaller bit and "cut out a circle" rather than "drill a hole" if they don't already have a 20mm bit. Unless the machine and bit are very stiff you're going to end up with a tapered hole. I tried this on my CNC table and had to go back with a drill bit and chase all of them. I bought a full size bit for the next time I do it, once I get everything squared up.

Programming charges for this project should be minimal. I could set up the file in about five minutes from opening the program to ready to cut.

Victor Robinson
01-04-2018, 12:25 PM
Of all the methods, the UJK Parf guide (that Lee Valley as well as TSO Products sell in the US) is probably the best combination of accuracy and price. It costs about as much as having one top made by a competent CNC operator, but you'll be able to make as many tops as you need. It's also the most labor-intensive since you're drilling (not even routing) each hole yourself.

The Woodrave jig is fine (I have it also) but you're dependent on the quality of the pegboard you source so if you're looking for absolute accuracy you might be disappointed.

Hoang N Nguyen
01-04-2018, 12:30 PM
I made a big MFT style table, 3'x6' and use it as an assembly table and outfeed table. Works great and love it. I'm lucky enough where the company I work for has a 20' CNC router and I was able to throw an entire sheet of MDF on it to have it cut.

If you do find a company to CNC the top for you, I would suggest having more than one cut and just saving it for later. This will increase the amount of machining time as well as cost, but would also entice the company to take on the job and save you money down the road when it comes time to replace. I use my table to make cuts with using my TS55 track saw so there's a lot of cut lines in it. Over time, stains, paints and glue gets on it as well and will need replacing.

Al Launier
01-04-2018, 12:46 PM
It's easy to make a jig to make these tops accurately yourself with a router. Watch Timothy Wilmot's bench video on YouTube...a simple tee-square with 30mm holes spaced at 96mm increments down the centerline for a 30mm guide bushing and the "tee" being the exact width to put the centerline from the previous row exactly 96mm over for the next row. You set it up to start 77mm from the corner in both directions. A 20mm router bit is relatively inexpensive, too.

I just watched the video. INCREDIBLE! What an ingenious design! And what a shop! Holy Moly!

Brad Shipton
01-04-2018, 1:02 PM
Cutting out these holes on a CNC is not that complicated, but I do agree you need to add a tolerance spec to the diameter callout for circles on your drawing. The tolerance should read 20mm -0.000" / +0.010" (assuming the exact diameter of the MFT dogs is 20mm). If you put a spec like that on the drawing and they ask what that is, go to someone else. Anyone with Biesse, CR Onsrud, Thermwood or another of the industrial machines can produce a ridiculously simple piece like this to a tolerance of 0.005". If you need better than that you are working with the wrong media. If you start talking to someone with a hobby machine you will need to make sure they understand the capability of their machine. I could produce this on my 4'x8' machine to within 0.010", but that takes time and the interest in setting up your machine to do so when you buy an entry level machine (grid squares in image below all within 0.010" so I can use vacuum pods).

I think Ted means an oblong hole. That will be largely the result of a sloppy operator that never checks the X/Y accuracy of his machine. So long as they use a 3/8" diameter bit, and the machine is not a cheap pile, using a pocket tool path is fine. If you spec that you want them to use a special bit they do not own, they will charge for that. A 20mm bit will be in the realm of $100 and they may need a $30 collet as well. Keep in mind you will be begging for someone to do this. Someone that owns a $100k machine could care less about your $100. The less annoying you are the more likely they will do it.

If you could live with a reduction in the length that will make the operators setup a bit quicker. To utilize the full 60" length without much extra setup time they would need popup pins. Most cab shops have that, but some of the smaller machines do not. Also, you can probably get two for very little cost. If it were me, I would charge you for the full sheet of Baltic Birch unless I had a piece kicking around.

375412

Keith Hankins
01-04-2018, 1:47 PM
I made my whole cnc 4x8 mft top so i could reuse my festool clams. You can also acomplish by making a jig and getting a forstner bit and do it that way.

Ted Derryberry
01-04-2018, 1:57 PM
I actually meant a tapered hole that is tighter at the bottom than it is at the top. My machine isn't so out of square that a 3/4" diameter hole is noticeably oblong! I don't even start to notice anything being oblong until I get to a 24" diameter circle and then it's within "sanding tolerances".

I was "drilling" using 1/2" bit on a spiral ramp to create a 3/4" hole through 1" MDF and 3/4" cabinet birch plywood. By the time it got through the bottom of the plywood the machine/router motor (not a spindle)/bit were flexing enough that it was trying to stay in the center of the hole. I couldn't get any of my dog clamps to fit and had to chase all the holes with a forstner bit. Now I know better and have a long 3/4" bit. Someone with less experience might be tempted to try the same thing in lieu of buying a 20mm bit, which I suspect is a little harder to find and more expensive than a 3/4".

In short there are two issues that could easily come up with a hobby machine and/or inexperienced operator. Out of square pattern and out of spec holes.

I agree the biggest issue is going to be finding someone with the proper machine that cares about a small job. The guy willing to take on the small job is less likely to have the machine capable of doing it well and the guy with the right machine can't be bothered. I'd probably go with one of the jig systems myself or make my own jig with very careful layout.

Brad Shipton
01-04-2018, 2:18 PM
That is interesting Ted. I have never had tapered holes, but I did have some oblong holes long ago when I did not always check my tolerances as carefully. I did a small project a few years back for someone where the a lot of dowels had to fit into holes, but the holes had to be quite reasonable so the dowels would not fall over. I nearly lost my mind, but I learned a lot about my machine. Small circular pockets are not the best on smaller machines. When I crank up the cut speed I can feel my machine vibrate back and forth a little bit and my machine still weighs 2600lb. There is a reason the industrial machines tend to weigh in around the 6,000lb+ mark.

Jim Becker
01-04-2018, 8:53 PM
I just watched the video. INCREDIBLE! What an ingenious design! And what a shop! Holy Moly!

Yes, the drilling jig is pure simplicity, although I will admit that the 20mm Freud bit I bought really needs a longer shank...I was, um...just barely getting through the 3/4" MDF with my jig being 1/2" thick. It's also only 1/4" shank and I'd prefer 8mm or 1/2" shank for this kind of job. If I make more tops, I'll likely look for another 20mm bit for the 'drilling'.

As to the rest of Timothy's setup...yea...it's really well thought out and executed. I'm building his MFSC and although there have been a few minor cut list issues, it's going well.

Jim Becker
01-04-2018, 8:56 PM
Cutting out these holes on a CNC is not that complicated, but I do agree you need to add a tolerance spec to the diameter callout for circles on your drawing. The tolerance should read 20mm -0.000" / +0.010" (assuming the exact diameter of the MFT dogs is 20mm).

The dogs for 20mm holes are typically 19.95-19.98mm. They can't be exactly 20mm or they'd be unusable. But that backs up your +/- specification. Smaller than 20mm is absolutely no-good. "Slightly" large by a tenth of a mm will likely be ok. CNC tool paths also have to be stepped enough to maintain tolerance at this depth of cut so there's no taper from excess lateral pressure on the cutter.

John Stankus
01-05-2018, 12:13 AM
On the Alpharetta Georgia craigslist there is a shop that is making these
Also there is a guy selling cad drawings for multifunction slab mfs (google it) so you can get you local CnC shop.
There are replacement mft tops and lee valley has something though it looks smaller
Dominofix has a jig to make your own

Google is your friend

Brad Shipton
01-05-2018, 9:46 AM
Thanks Jim. I had never measured my MFT hold downs, so that is why I assumed the size. Industrial CNC machines drive 3/8" and 1/2" diameter bits at 1000 - 2000ipm in many different woods cutting irregular shapes where you would see taper if you bit deflection were a problem. That is the reason they need 25 - 40hp vacuums for stock hold down. The head cannot accelerate to speeds anywhere near that speed for such small holes, so I highly doubt taper would be an issue with a reasonable machine.

laura vianello
01-06-2018, 7:56 AM
Thanks Jim, the table would be used to do cross cutting with the Festool track saw. I always have hard time with perfect 90. I created a jig with pins (instead of dogholes) but it has been hard to drill 90, drill perfectly spaced and aligned. I blamed my measurement tools and my power but there is more into this...So I decided to go for the perfect bench. While I can buy the Festool top, it does not have the dimension I want. I will look into your suggestion but I used the router only once and because I do not have dust collection on it, it is not my first choice. However I have not seen that video so I might change my mind. Thanks a lot for your suggestion

laura vianello
01-06-2018, 7:57 AM
Thanks, interesting option.

laura vianello
01-06-2018, 8:01 AM
I looked into this, however I read a lot about people struggling with aligned peg boards. It is a great idea but it relays on no so grate material that you need to be sure is perfectly manufactured. I got a little scared on spending time on the right peg board. Quality at the big box store is very poor as far as the measurement tool I buy there :(
Thanks for your valuable suggestion.

laura vianello
01-06-2018, 8:03 AM
Jim, see my message above. Thanks for your help. Interesting that you could use it exactly for squaring table.

laura vianello
01-06-2018, 8:06 AM
That is a possibility, I wish the table top was not $140 min. It would be nice to have a 1x1 square jig. Bench dogs are on their way!!! Thanks

laura vianello
01-06-2018, 8:07 AM
Good point. I think I will get the Parf system and call the day ;)

laura vianello
01-06-2018, 8:10 AM
I looked at it but there was a deadline to order. It is passed. Too long of a lead time at this point. Excellent suggestion. Thanks

laura vianello
01-06-2018, 8:12 AM
That is great! What is the new dead line? Which items did you buy? Why did you feel that it was better than Parf system? Do you have Veritas benchdog? Tx

laura vianello
01-06-2018, 8:15 AM
I spent tons of time on FOG. That is why I post here to look for a reputable CNC. In Fog it was the mainly suggestion because there are not better holes than 1) CNC, 2) routed with LR32 and Festool router and 3) Parf system. I decided to ask for CNC but at this point I might go for Parf. It looks like I can resell when I am done and recoup some of the expenses. Tx

laura vianello
01-06-2018, 8:18 AM
Is it an offer? I do not have a CNC.

laura vianello
01-06-2018, 8:19 AM
Yes, I love the Parf System. I am currently evaluating if I need a corded drill though. My 2 cordless are not going to to make it. Do you think I need a corded?

laura vianello
01-06-2018, 8:24 AM
Thanks Hoang, to have 2 is not an option because of space. I would use the table 45 min a day if lucky. I have a full time job and 2 kids. This activities is on the side. I do not think I will mess up because I will try to use sacrificial board to avoid replacement for something too painful to have. Thanks and enjoy your 3x6 ...sounds like a dream!!

laura vianello
01-06-2018, 8:35 AM
I was looking for a 24x50. We are discussing about talking with a CNC shop but I do not have a name. On the other hand I am probably “annoying” because I want things right. To have a table that does not suit the purpose is a waste of time, material and money. In addition ...I am a woman...that does not help either in woodworking. That is why I was looking for a reputable name that was used before by a member. I just stopped going to a local Woodcraft store because of attitude that I did not need. My money are the same money you spend. Anyway, I might just go for the Parf guide and blame myself is something goes wrong. Thanks for your suggestions.

Brad Shipton
01-06-2018, 10:18 AM
The best way to find a CNC is to start going to cab shops that are a reasonable size. When you go you should have a drawing in hand and a .dxf file. Most cab shops have CNC's and if you tell them exactly what you want they may be able to persuade them to make it. Craiglist was another good suggestion. There are lots of shops that do not quite have enough work volume to keep their machines running so they custom cut for other shops. Craiglists is a place some will post these offers. Shipping cost for this part size will add a bit I suspect, so it would be best to find someone nearby you can talk to face to face. It might not be a bad idea to find someone if you like the idea of CNC cut parts for the future.

If you do not have the software to prepare a drawing post a sketch and I can prepare a drawing and .dxf file for you. It would take me 5 or 10min is all if you sketch is clear.

I would probably buy the jig suggested and move on with life.

Keith Outten
01-06-2018, 11:14 AM
The best way to find a CNC operator is to visit our CNC Forum and ask your question. You won't find more qualified operators anywhere that right here at SawMill Creek.

Laura, your job is a cake walk. It should be very easy to get it done accurately in an hour or less.

laura vianello
01-06-2018, 7:49 PM
Thanks Keith, I just bought the Parf system for luck of hope to find a CNC reputable shop...too many negative stories. it looked very complicated. If I failed I will be back to the drawing table :)