What length of faceplate screws should I use?

[Jesse Tutterrow]

How long does the screw have to penetrate into the wood to get a good hold? I realize that this depends upon the size of the blank I am turning but I hope to get a general rule of thumb.

At the moment I want to turn a 8" diameter by 1.5" thick blank as practice for platter turning. Finished platter would be about 1 to 1 1/4" thick.

 

[john lucas]

Platters are side grain so the screws hold really well. So I would say if they go in 3/4" you should have plenty. I turn platters using double stick tape or a screw center. For thin stock I use the double stick tape and turn the platter back with a rebate for the chuck. I use 4" jaws for the rebate. For thicker platters I start with a screw chuck that has a spacer on it so that it will only penetrated about 3/4". Then I turn the bottom and again use the rebate. I have also used glue blocks that I apply with medium CA and accelerator. I can easily break the glue joint when I"m done.

 

[Bill Boehme]

Always put screws in all of the holes and use screws that have deep sharp edged threads. The screws need to be long enough to get a solid hold in the wood. I generally go overboard on length, but if the wood is hard and solid then going deeper than an inch into the wood doesn't buy you much additional holding ability. On tall heavy hollowforms I use screws that go 1 1/2" into the wood. I strongly recommend predrilling the holes so that they don't split the wood. Never ever use hardened drywall type screws.

 

[hockenbery]

At the moment I want to turn a 8" diameter by 1.5" thick blank as practice for platter turning. Finished platter would be about 1 to 1 1/4" thick.

This blank is not thick enough for a faceplate tenon
The tenon for the faceplate holds the screws is usually waste wood.
The tenon should be a 1/4” longer than the screw penetration because the screws open a hole in front of them of about an 1/8” but never in my experience a 1/4”.
With 1” screw depth I use a tenon 1 1/4” long
With 3/4 inch screw dept you need an inch.

I use a faceplate on most of my hollowforms.

You can mount a glue block to a faceplate and glue that to your blank.

Or on a blank that size a chuck works great.

 

[Mike Johnson]

If the wood blank lacks in depth you can always glue another waste block to the piece. On a single slab of wood depending on the thickness of the slab you can use a length of screw that will not have a conflict with your depth of turning desired. Shorter screws usually require a larger number to secure the wood slab to the face plate. I have a supply of wood turned tenons that can be glued to a flat slab and then mounted in an adjustable chuck for wood turning, this eliminates the face plate/screw issue. A tenon can be turned on a wood slab while it is mounted between centers, or a recess can be turned while the piece is mounted between centers, this method can be used to eliminate the face plate/screws issue. I use this method when turning platters and saucer shaped pieces, a glued on tenon or turned recess allows quick mounting into an adjustable chuck. If a wood turner does not have an adjustable chuck (bowl chuck) then you are limited to working between centers with a face plate mounting or between spur drive and tail stock. You could also use a jamb chuck arrangement between centers if you have experience turning with this type of tooling. Jamb chucks provide the frictions required to hold the piece between centers while turning and finishing. Double sided tape would be another option with a face plate which can be successful if you have experience using this mounting method along with the assistance of the tail stock when roughing the piece. Without tail stock support you must take care in making cuts to the tape mounted piece whereas a good tool catch can cause the double sided tape to fail.

 

[Breck Whitworth]

There are so many different ways to do the same thing so I will agree with Bill and always use a screw in all the face plate holes even if you think it won't matter. I use wood screws that hold well into the wood and never never never use dry wall or sheet rock screws they are so brittle they tend to break to easily. If I am going to make a bowl the depth of screws should never exceed the depth of the bowl bottom, I know common sense huh? I drop a screw into the face plate while in my hand then see how far the screw extends beneath the faceplate I lay it on the piece I am working with just to make sure I have enough screw threads to hold but not go too deep.

 

[Emiliano Achaval]

Make sure you dont use deck wood screws, or other thin wood screws. I use (I think) #10 Sheet metal screws.

 

[JeffSmith]

As the former owner of a wooden boat that was under renovation from the moment it was purchased, I have a huge reserve of screws left over - from standard steel and brass to silicone bronze and stainless. The ones that have survived years of turning, and reside in a box in the drawer with my faceplates for ready use are large (#12 or better) squaredrive stainless button-headed sheetmetal screws. A sampling of lengths gets just about anything mounted, and they last virtually forever - the combination of square drive with the added strength of the stainless means I’ve retired several drives but still use the same screws that have lived in the drawer for over a decade.
Fill all the holes in the faceplate and predrill as Bill mentioned...as for length, long enough to hold, short enough not to show. If the blank doesn’t have enough wastewood, a layer of double-sided turner’s tape gives a little extra security.

 

[Larry Copas]

I bought a old Delta lathe at a school auction when they closed down shop classes. This was the faceplate that was on the spindle.



Sometimes I wonder.......

 

[Bill Boehme]

I bought a old Delta lathe at a school auction when they closed down shop classes. This was the faceplate that was on the spindle.

View attachment 25382

Sometimes I wonder.......

A little cleaning up, a little Bond-O, and a fresh oat of paint and that puppy is as good as new.

The headless screw could be an ominous sign.

 

[hockenbery]

I bought a old Delta lathe at a school auction when they closed down shop classes. This was the faceplate that was on the spindle.

View attachment 25382

Sometimes I wonder.......

A little rough about the edges. Once you get it broken in it should be fine.

 

[Bernie Hrytzak]

I would be concerned about the fractures in the cast iron around the thread area, looks like another piece is ready to fall off. That is the area that should make face contact with the lathe spindle for keeping things squarely line up.

 

[Hy Tran]

How long does the screw have to penetrate into the wood to get a good hold? I realize that this depends upon the size of the blank I am turning but I hope to get a general rule of thumb.

At the moment I want to turn a 8" diameter by 1.5" thick blank as practice for platter turning. Finished platter would be about 1 to 1 1/4" thick.

Hello, Jesse,

Not counting the point of the screw, in wood, you generally want to engage a minimum of 4x the diameter of the screw for maximum strength against pull-out. If you're using a #10 screw, the diameter of the screw is 0.19 inches; if you're using a #12 screw, the diameter is 0.216 inches. (I don't have a handheld calculator handy, so you do the multiplication by 4 yourself )

As the others said: Don't use a drywall screw. Look for a sheet metal screw (technically, a "thread tapping screw"). Production screws (used for production carpentry with powered or impact drivers, brands such as GRK or Spax), in my opinion, are also a good choice. Square drive (Robertson), Hex (Allen) or Torx are my preferences for drive type, followed by pozidriv. Craft supplies sells a bag of 100 faceplate screws (square drive, round head) which I find perfectly adequate for a midi-lathe-sized faceplate.

I generally pre-drill a small pilot hole in the wood (just a bit smaller than the root diameter of the screw). The better faceplates have a relief on the wood side of the faceplate to allow for the wood to "mushroom" a little as the screw goes in.

I prefer using a consumer grade (inexpensive porter cable at big box store) battery-powered impact driver to drive the screw in.

Hope this helps!

Hy

 

[John Torchick]

Curious- why not deck or drywall screws? Threads not adequate?

 

[John Tisdale]

I use #14 ss sheetmetal oval-head - on the inner holes a 1.25" and a 1" on the outer holes. I guess the extension is a bit less than some recommend but I've never had a problem.
I center each hole with self-center hinge bit and then drill to exact depth with a 11/64. I also grind the tips off the 1" screws on the outside - allows me to use a 6" faceplate and then turn down to a 4" base - I typically turn an inch under the faceplate before turning the 1/4" flat for the base.
As the above is confusing, will sent pics if you want.

 

[hockenbery]

Curious- why not deck or drywall screws? Threads not adequate?

Drywall Screws are too brittle, they don’t make them thick enough, and the threads are thin.

Screws need to go in and out. Reusability is a plus.

A broken screw takes a while to get out and it isn’t fun.
The big down side to drywall screws is you will break them a hundred times more often than a #12 sheetmetal screw. While drywall screws don’t hold as well as #12sheet metal screws, they probably hold well enough. #12sheet metal rarely break. Hundreds maybe thousands of mounts between a break ( of course you are replacing screws because the driver part is stripped)

I mostly use stainless steel #12 sheet metal screws. The stainlessmavoids the black marks. I use stainless faceplates usually.
Also a drywall is much more likely to pull out than than a #12 sheet metal.

 

[Bill Boehme]

Curious- why not deck or drywall screws? Threads not adequate?

What Al said. Often a drywall screw will go in and torque down without breaking, but when it is time to remove the screw the head will snap off. This is due to the high tensile load put on the screw when driving into hardwood combined with the high breakout friction to get the screw turning when it is removed. When drywall type screws break it seems like they nearly always snap off just proud of the wood surface. As Al said it's no fun digging out a broken screw.

Drywall screws and deck screws both use bugle heads which is fine for their intended purpose of sinking flush into soft material, but they're not compatible with faceplate holes.

In my opinion, deck screws are best considered one-shot fasteners just one step up from using nails. They're made to go in, but not to come out. Last year I started removing the screws on my deck. Out of a couple thousand screws removed about a fourth of them snapped off and had to be removed with Vise Grips. I'll be using SS fasteners on the new deck.

 

[Emiliano Achaval]

Using the wrong screws reminds me of the never ending story of new turners using the spindle roughing gouge on side grain. It's probably the 2 most common mistakes when someone gets started without a mentor or by watching the YouTube experts.

 

[Glenn Lefley]

Curious- why not deck or drywall screws? Threads not adequate?

That’s why screws are not allowed in house construction when framing. They have no sheer strength. Put a drywall or deck screw through s board with it sticking out an inch or two. Hit it with a hammer and it will break off on first hit. Now grk and spax are a different storey. They cost a dollar each for a reason. They are structural screws.

 

[Emiliano Achaval]

That’s why screws are not allowed in house construction when framing. They have no sheer strength. Put a drywall or deck screw through s board with it sticking out an inch or two. Hit it with a hammer and it will break off on first hit. Now grk and spax are a different storey. They cost a dollar each for a reason. They are structural screws.

Wonder if they are good enough for the faceplate? As strong as sheet metal screws? Reusable? Always good to have an option...

 

[Glenn Lefley]

Wonder if they are good enough for the faceplate? As strong as sheet metal screws? Reusable? Always good to have an option...

Stainless steel would be in the structural category. Good for faceplates.

 

[Owen Lowe]

Not counting the point of the screw, in wood, you generally want to engage a minimum of 4x the diameter of the screw for maximum strength against pull-out. If you're using a #10 screw, the diameter of the screw is 0.19 inches; if you're using a #12 screw, the diameter is 0.216 inches. (I don't have a handheld calculator handy, so you do the multiplication by 4 yourself )

Right. Once the risk of pull-out is eliminated, the screws' main job is to resist shear forces of the rotation & cutting pressure. Driving in longer screws won’t help much at all once pull-out is satisfied because it all comes down to the same shear forces on the screw shaft where the faceplate and wood mate.

I have used the blue Tapcon screws that are intended for concrete construction for years and years. I think I’m still on the same original batch — they really don’t seem to wear out — the phillips/square drive heads are still quite functional. They have a double-thread type of design and I sharpen the end to a pointier profile to ease entering the wood.

 

[John Torchick]

I have Tapcon screws with the hex head/slotted head. Got a lot of stuff on the block wall in the shop. Thanks for the replies, confirmed what I thought. I do use DW screws for some of the tables, etc. that I have in the shop. So far, so good. I did build a table for my DP and BS. Glued the joints before driving the screws.

 

[Bill Boehme]

I have Tapcon screws with the hex head/slotted head. Got a lot of stuff on the block wall in the shop. Thanks for the replies, confirmed what I thought. I do use DW screws for some of the tables, etc. that I have in the shop. So far, so good. I did build a table for my DP and BS. Glued the joints before driving the screws.

It's probably OK to use them for cabinets. There are similar looking coarse pitch screws that aren't brittle.

 

[John Torchick]

Again, thanks for the info on using DW screws in a faceplate. Needing to turn some small bowls or platters.