Mark Phillips (ripsteel@edge.net) adds: A neat trick is to wrap a rubber band or
two all the way around that "thing that holds the rivet die" and the yoke of
the squeezer- this will keep it from rotating and doesn't interfere with the
action of the squeezer!
Brian Denk <akroguy@wizrealm.com> says:
Do NOT use ATS rivet sets!! I borrowed one for #4's and mangled so many it made
me sick. Once I bought one from Avery's...like magic...came out perfect! I also
have one of their long, offset back sets...which I plan to use as much as
possible on the skins.
Air pressure settings....about 25-30psi for the rivet gun and touch-up spray gun for priming. I run a full 100psi to the air drill.
I use about 30psi for driving 3/32" rivets, 50 for 1/8" rivets, 50 or so for spraying, 90 for the drill.
RV-List message posted by: "Fesenbek, Gary"<gfesenbek@meridium.com>: I needed to buck a few rivets inside the canopy rail and just did not have a bucking bar that would fit in there. I decided to try my 4" no hole yoke for my Avery hand tool and must report that that thing works absolutely great as a bucking bar especially for -3 rivets. It can fit almost anywhere you can get your fingers into, is easily aligned and held and does not make a mess with the surrounding skin.
| Rivet dia | Drill size | Cleco color | Bucking bar wt | Edge dist. | Rivet pitch |
|
1/16 |
51 |
||||
| 3/32 | 40 | Silver | 2-3lbs | 6/32 | 9/32 |
| 1/8 | 30 | Copper | 3-4 | 1/4 | 3/8 |
| 5/32 | 21 | Black | 3-4.5 | 10/32 | 15/32 |
| 3/16 | 11 | Gold | 4-5 | 6/16 | 9/16 |
|
1/4 |
6.4mm |
Similarly, the rivet pitch, that is to say, the distance from the center of one rivet to the next is again a function of the rivet size. The center of a rivet of X diameter should be 3X away from the center of the next rivet.
In actual fact, these edge distances are slightly affected by countersinking and dimpling, and the EXACT edge distances that Van uses for his strength calculations are at the Mil-Spec on Gil Alexander's web site.
However, the minimum pitch you quoted seems almost like a "tear along the dotted line" instruction ...:^) It is different (by quite a large amount) for c/s and dimpled rivets - see Table VI on the Spec. above. The pitch you mentioned would fall under the following quote: "Lesser minimum spacings require government design activity approval unless otherwise indicated on the drawing"
I wouldn't put a row of structural rivets at the 3x pitch UNLESS that was actually called out for in Vans drawings.
RV-List message posted by: Kevin Horton<khorton@cyberus.ca>: For 1/8 rivets, the minimum shop head diameter is 0.163 and the minimum head height is 0.050. Both these values are quite a bit less than the oft quoted 1.5D and 0.5D.
| Catalog Method (AN or MS20) |
Head Style | Alloy | Diameter (1/32") |
Length (1/16") |
|
| Example Designation | AN | 470 | AD | 4 | 4 |
| Meaning | Air Force Navy | Universal Head | 2117T4 | 4/32" | 4/16" |
Gary Vanremog<Vanremog@aol.com>: A 7/64th steel rivet is weaker than a -3 AN rivet.
This is based on my shear tests at work using a calibrated Chattilon pull tester. I don't remember the actual values now (it was almost five years ago when I first started the project).
The MK-319-BS 7/64th rivet is not steel, but Monel (67% Nickel/30% Copper) with a steel mandrel that doesn't always stay in place. With the mandrel in place they were about 75% of the strength of a properly installed AN426-3 rivet in shear.
I didn't test tension but I assume this is also less because the shear test almost pulled the dimple flat on the Monel pop rivet sample and the shank deformed significantly prior to the break. The AN sample merely sheared in place with little surrounding hole deformation so the rivet kept its heads intact.
RV-List message posted by: "Bryan E. Files"<BFiles@corecom.net>: The only requirement for bolts that I know of is that bolts should provide full bearing surface for the bolt head and nut.
RV-List message posted by: Hal Kempthorne<kempthorne@earthlink.net>: This does seem to be the rule. I looked in my old Mechanical Engineering Design by Shigley book. He says roughly that bolts are normally arranged such that edge distance is not a problem!
It seems to me, however, that the material being bolted is a consideration calling for a larger edge distance with less strong materials.
Bolts do a lot of clamping over rivets. So, calculating the strength of a joint by evaluating the load carrying ability of the section of the parts to be joined is too conservative for bolts. In many machines you can see a bolt thru a part whose hole is a slot rather than a neat round hole. The slot allows for variations in fit at assembly time. The parts are held in position by clamping force, just as a C clamp or cleco does rather than by a precision hole.RV-List message posted by: ammeterj@home.com (John Ammeter) about bolt sizes:
Diameter is in 16ths while length is in 8ths.
An AN3-4 is a bolt that is 3/16" in diameter and 4/8" from the face of the head to the end of the bolt. There is no AN3-8 bolt since that would be one inch long and then it is called an AN3-10 or 1" plus 0/16". An AN5-23 bolt would be a bolt that is 5/16" in diameter and 2 3/8" long.
For tube nuts and 6061/5052 aluminium tube:
1/8
20 to 25 in/lb
3/16 25
to 35 in/lb
1/4
40 to 65 in/lb
5/16 60
to 80 in/lb
3/8
75 to 125 in/lb
1/2
150 to 250 in/lb
5/8
200 to 350 in/lb
3/4
300 to 500 in/lb
Hose couplings generally x1.5 but check to get the right values in a reference
book. This is out of the IAP Standard Aviation Maintainence Handbook, fig 6-25
p142. Other fitting combinations have different values.
RV-List message posted by: Vanremog@aol.com
Here are the torque values (+00%/-20% tol) we used at my last company for light
duty fastenings using steel (or stainless steel) screws into steel threads. If
you are going into aluminum threads multiply by .75 (75%). If going into a
thread form having a prevailing torque feature, add the prevailing torque to
the tightening torque in the table to get the final torque.
thread lb-in
0-80
1.0
2-56
2.0
4-40
5.5
6-32
10.0
8-32
20.0
10-32
28.0
RV-List message posted by: Vanremog@aol.com regarding screw hole sizes: This is from a chart I used at Lockheed:
2-56 screw clearance hole = .09375" = 3/32" or #41 drill
4-40 screw clearance hole = .12500" = 1/8" or #30 drill
6-32 screw clearance hole = .15625" = 5/32" or #22 drill
8-32 screw clearance hole = .18750" = #13 or 3/16" drill
10-32 screw clearance hole = .20313" = 13/64" or #6 drill
RV-List message posted by: Tom Barnes<skytop@megsinet.net>: Rather than using the standard AN426AD3-x to attach the platenut, I use the oops rivits (NAS1097-AD3-3.5 ) in Van's Summer catalog 1998 page 46. These rivets have 3/32 shanks but smaller than normal heads. They can be countersunk easily with 10-12 turns of Avery's deburring tool. This works in metal as thin as .025 with room to spare.
1. Drill a hole into the factory head (*not* shank) of the rivet. Use a drill size smaller than the rivet's size i.e. for a -4 rivet, drill this hole with a #40 or so bit. There's a dimple in the middle of the rivet head to use as a starting point. Turn the drill bit by hand a couple of times to get started exactly centred. Better yet, use a small automatic centerpunch to punch the head to get a good centre before drilling.
2. Pop off the head with a 3/32 inch pin punch or an old dull drill bit shank (exact same diameter as the hole!). Put the hardened end into the hole you just drilled and tilt slightly and the head will pop off once you have learned to drill the proper depth. This is more difficult with flush rivets than universals. If your drilling is accurate and you go slightly too deep, no problem. However, if your drilling is inaccurate and you go too deep, you'll damage the hole. For the real tough ones, use a *VERY* sharp chisel laid flat with the skin and tapped with a small plastic faced "dead blow" (shot filled) hammer that weighs less than 8 oz.
3. Drill down through the shank using the smaller bit, again being careful to keep it centred. This hole is important because it relieves the grip between rivet and hole.
4. Grasp the shop head tightly with a pair of long-nose pliers and twist and pull. The shop head and remains of the shank should come right out. If not, pull harder! Inspect the shank... hopefully the drill stayed inside the shank right through the hole. If not, the hole was probably enlarged a little.
5. Stop and think *why* did this rivet go bad. Is it something with your technique? Perhaps due to the awkward position/angle of the rivet? Or maybe it was just one of those things?
6. I've found that, with care, this should allow you to put another rivet the same size and length in the hole. However, if you need to drill out a second rivet from the same hole, the hole will almost certainly be enlarged.
7. If the hole is enlarged just a little, take a slightly longer but same diameter rivet, and squeeze it down a bit in your handsqueezer. Not in the workpiece, just loose in the squeezer. If it bends, throw it away and do another. When it's fattened up to the right diameter for the hole, and the correct length, insert it in the hole and drive as usual. Alternatively, use NAS 1097 "cheater rivets" which have the shank of the next size rivet with the smaller head of the old size. (-3 head with -4 shank)
8. If you screw up driving a fattened-up rivet, stop and take a break. Maybe stop rivetting and do something else for the rest of this session. It's probably late at night and you're maybe tired. You're probably also feeling frustrated, stressed out, and have lost some confidence. A rivet driven while in this state of mind will probably also be bad.
9. Next morning, consider your options. Have another look at that rivet. Consider whether it *really* needs to be drilled out. If it does, drill it out again as per steps 1-5, then drill the hole out to the next size up rivet.
10. Stop and think *why* these rivets are all going bad. It it something with your technique? Perhaps due to the awkward position/angle of the rivet? By now, there *is* SOME reason why you can't drive that rivet. Get someone to help, or to watch your technique. Correct that problem. Then drive the rivet and move on.
However, there are several other ways to achieve the same results.
I've used my jigsaw very successfully to cut large, odd-shaped holes.
If you want a slower, more accurate approach, try this:
Sam Richards crcar@cc.newcastle.edu.au said to the RV-list: The humble jeweler's
saw is a quick answer to the cutting of odd shaped or odd sized holes. This
type of saw is similar to a coping saw except the blades are clamped in
position rather than with the use of hooks and lugs. These are available from
hobby shops and jewelry tool suppliers. A wide variety of blade grades can be
had - from the coarsness of coping saw blades to teeth so fine you need a
magnifier to see them. Need a square hole in a panel for a switch? Forget about
countless drill holes and a file. It can be cut out to nearly the exact size
then finished with a fine file.
The blades come in packs of 12 or 144 and (as implied) are easily broken until you get used to them. To start a cut in the middle of a piece of material, drill a small hole in the waste section; unclamp one end of the blade; pass it through the hole and reclamp. Saw the hole and unclamp to extract the blade. Blades need to be clamped under tension, so before you tighten the clamp push the tip of the saw frame against a solid surface to 'flex' it slightly, then clamp and withdraw the pressure. The blade should sound with a 'ping' when plucked like a harp. If not, try retensioning.
William H. Watson <wmwatson@earthlink.net> wrote to the RV-list: I bought the 1/4" Aircraft Taper Pin Router Bit, p/n 933-4 from Avery, $9.00. Chuck it up in your die grinder and you have an instant,hand-held, milling machine. It's like a Dremmel on steroids.
Rough cut the shape or the hole, finish to final dimentions in minutes. So far, I have used it on the tank access hole, tank forward 1/4" angle flange, landing light hole, and push rod hole in rear wing spar. Clamp the work well. A short learning curve is needed to avoid chatter.
However, it *is* important to prime the steel parts when the kit arrives or soon after. I thought I'd leave that until later so they wouldn't get scratched. So, instead of maybe a few scratches getting corroded, the entire surface did. Sheesh! Talk about not thinking!
Here's what I do:
My priming session starts by lightly rubbing the work pieces with Scotchbrite,
just enough to take the shine off, to roughen the surface a little. Then wash
down with ICI (Dulux) Deoxidine (a phosphoric acid etch, I guess the same as
PPG DX533), leave for a couple of minutes, then rinse off with warm water. Dry
down, then wipe down with Prepsol to get rid of organic stuff. Dry (being
careful not to get fingers on the part) with a lint-free (more or less) cloth,
then paint. 
It's not worth going through all that, and the attendant cleaning up for single items, so I work on several components, then have a big spray session. Because I only have a small compressor (1/2hp) and tank, I can't paint much in one go, so I have various items in various stages of this process at the same time.
The deoxidine I just wipe on with a rag (rubber gloves, of course -- it froths kinda neatly when it lands on concrete), and keep the gloves on for the rinse off. Rinsing, I stand the item up in the bucket of water and wipe it down with a rag, splashing on plenty of water.
I replace the water fairly often... I just chuck it out over the concrete, aiming for it to kill the moss and stuff, and to stop the grass from growing over the path.
I started using ICI Dulux PA-10 automotive primer, but I understand there's some limitations on what can be put over the top of it. Nowadays, I use Croda Port-Etch 2-part epoxy primer. This is easy to mix, easy to spray, and produces a good hard surface.
Hint: Before painting, blow air through all the holes in thick items like spar stiffeners. Otherwise, when you paint one side, it'll blow water out of the hole and onto the other surface. You paint that, and it'll be a mess.
RV-List message posted by: Unistar Computers<unistar@mindspring.com>: How to prime (or paint) small objects without blowing them away with the spray gun? Put all your small pieces on screen wire and paint "through" them. The air will go right past the parts and not disturb them. The size of the screen varies with the size of the piece(s) to be painted. Chicken wire or Rabbit wire for larger parts, window screen for tiny parts.
RV-List message posted by: robin.y.wessel@exgate.tek.com: While surfing around I found this great WWWboard about spray painting. The site is hosted by some experienced paint jobbers - great reading!
http://Autobodystore.com/discussi.htm
1)If you prime early on, you'll need to scuff the primer and maybe reshoot a light prime to get the paint to stick.
2)The primed surfaces will get greasy, dirty, etc. with all the handling they will endure. More work like in #1, plus the need to remove the dirt and grease.
3)If you decide to glue (proseal, fiberglass, etc) anything to a primed part, the primer has to be taken off first....
4)You may pick a primer on the front end that is not compatible with the best finish systems available when you go to paint the aircraft. OR, if you have the plane professionally painted, the shop may not be comfortable putting their finish on your primer..
Try this for keeping all the braided shield wires out of harming ways . . .
1) Put 1" piece of 3/16" heatshrink over end of wire to be terminated.
2) Remove outer insulation to expose shield braid approx 1" from end of wire.
3) Push shield braid back slightly so as to "bunch" it up a bit right at the end of the outer insulation jacket.
4) Bend braid and internal conductors over right at the end of the outer jacket to make a "J" shape on end of wire.
5) Use blunted pick to tease an opening into the side of the shield braid exposing the wires within.
6) Use the pick to get under the wires and pull them out through the opening.
7) Pull the shield braid back out straight and twist the ends just slightly to take care of the "fuzzies" at the end.
8) Put piece of 3/16" heatshrink over shield braid leaving approx 3/16" exposed. Shrink down. Install PIDG or similar terminal on end of braid.
8) Install PIDG or similar terminal on center conductor(s).
9) Slide heat shrink from step (1) so that 1/3 of its length is past end of shielded wire's outer jacket and shrink in place.
This technique prevents damage to center conductor insulation since only standard strip-and-terminate operations are carried out. "Fuzzies" from stray shield braid are corraled because there's no attempt to "unbraid" or comb out the strands in an effort to make the center conductor accesable. ALL conductors are ultimately covered with insulation exposing only the portion of the terminals necessary for connection.
Pure aluminium is too soft for structural members. With the addition of various other metals such as copper, zinc, chromium, nickel, silicon, manganese, etc, the aluminium can be manufactured in structural strengths equivalent to that of steel. This is advantageous because the aluminium alloy is about one third lighter than steel.
However, these alloys are much more suscepible to corrosion than pure aluminium. The manufacturer therefore puts a coating of pure aluminium on both sides of the alloy. This is referred to as "Alclad". The surface is very soft and scratches easily. We must therefore take special care in handling Alclad material:
Brian Denk <akroguy@wizrealm.com> says:
I use a tool pouch around my waist..to keep clecos and pliers.
A plastic handy tote, with four compartments is used for small, often used items such as measuring tools, pens, centerpunch, files, deburring bits, emery paper, BANDAIDS, and the like.
My shop has LOTS of lighting...fluorescents and portable halogen flood lights on the floor. Eye fatigue sucks! I also painted the floor white...helps to reflect light upwards, into your work area.
I perform like operations..requiring a certain tooling setup on as many parts as possible. Like, skin stiffeners..cut them ALL for the elevators and rudder at one time. Then, deburr and polish the edges on ALL of them with the Dremel wheel..then, hole space them....using my underwear elastic band spacer rig! (ask me about this one, if ya need to!) Then, locate and drill ALL of them into place. Priming is optional of course...I choose to prime the ENTIRE interior of the plane...I like the peace of mind.
I mark ANYTHING that can even remotely be confused with an opposite side, like part. A Sharpie pen shows through Variprime if you don't wipe it off during the cleaning before priming.
For the small parts, and hardware, I bought two, 50 drawer small parts organizers. It required one for the tailkit and wingkit hardware, and the other will be used for the fuselage. I marked every drawer during inventory with their contents..and put them in a logical order...rivets first, from small to large, then nuts/bolts, then fittings and brackets, and put the deburring/drilling bits, sets and dies near the bottom.
One indispensable gadget that is a MUST have: the pop rivet tool dimple die...awesome! I can't imagine getting the last two stiffener holes (near the trailing edge) dimpled without them.. and I found the results to be absolutely acceptable...you'd think I made them with the C frame tool. I even used them in places where the squeezer or C frame tool would normally be used...such a neat little tool!
From the RV-list:
I was shown a neat way of filling those unwanted holes so they are almost
impossible to see after the paint has gone on and thought someone on the list
might find it useful. I have used it on a couple of occasions in the HS skin
(so far).
This will work for some slightly elongated holes, but suggest drilling out to the next bigger size rivet. It needs a little practice on scrap before plunging in on your project. I haven't had to fill figure eight holes though I think it would probably work with care. It will not work in really thin control surface skins.
Firstly, deburr the hole both sides, a little more than you would normally - so that you form a mini countersink both sides. (This is why it won't work in thin skins). Take it easy, it doesn't have to be too big - just a definite chamfered edge. Next find a rivet that is a close fit to the hole and using your rivet cutter - cut the end off the rivet. I have been able to use just 1/16inch lengths. Discard the rivet part with the head! You can use several bits from one rivet if it is long enough (and you have to fill a couple of holes). Next use a pair of pliers to hold the rivet and file smooth the cut surface as flat and square as possible. Place the skin exterior surface down on your back-rivetting plate or some other polished steel surface. Hold firmly down. Place the rivet in the hole, flat surface down on the plate and then using a light hammer, tap the rivet. It will swell and fill the hole and the mini countersink beautifully. Don't overdo it as you may swell the hole.
It takes a little practice but it looks wonderful on the exterior surface and
won't budge. The other side can be filed or machined down if you wish, but if
it is not in the way, I have left it.
Is the skin salvagable? Any suggestions? Yes, it is probably salvageable, unless the rivet will also hold the rib to the spar or something like that. I did something similar on an elevator.
Firstly, to correct the bad technique: Ensure that the skin is sitting down firmly on the dimple die, with the male die in the hole, before hitting. HOld the skin down whilst hitting.
To fix the bad part: Add a couple of rivets either side of the bad rivet hole, so that they all have good edge distance. Make sure you choose good locations (ie you can successfully drive and buck them) for these rivets. These will take the forces the original rivet was meant to, so the original rivet is now merely a cosmetic problem. If the extra hole is close to the original hole, you may be able to drill the original out to #30 and use a larger -4 rivet in the original hole to cover the extra one. If the holes are too far apart, put a -3 rivet in each one.
Note that a fix like the above probably means the end of your dream of OSH Grand Champion. That's not necessarily a bad thing, since it'll allow you to get on with building a good solid plane rather than a trying to do a perfect one.
Fom an RV-List message posted by: David Peck<dpeck@ozemail.com.au>: I bought some new edge clamps and spring tension clamps and was worried that themanufacturing forging marks could scratch aluminium, so I painted a layer of ProSeal on the jaws and now have non scratch clamps.
RV-List message posted by: Bob Skinner<bskinr@trib.com>: The Avery edge
rolling tool works much better if you stick some of the self-adhesive, UHMW
tape on the surface of the aluminum disk. The tool will roll much easier, there
will be no metal to metal contact and, as a result, no burrs are formed on the
edge.
1. Tube level. This can be used to get the wing spar mounted level on the jigs, and later to level the fuselage in pitch. Get a 1/4" or so diameter clear PVC tube around 12 feet long. Boiling an ounce or two of water a few minutes, cool, and adding a drop or two liquid soap will help eliminate gas bubbles and allow the water to "wet" the tube. Fill the tube about 80% full of this water, and duct tape one end of the tube to the end of the jig or whatever you want level, and then move the other end up and down until the water level is where it is most useful. Do not use too small a tube for this, as bubbles which are as big as the ID of the tube will make it inaccurate.
2. $85 engine hoist. The base is a rectangle consisting of two 60" and two 49" 2x4's, bolted together with two 1/4" carriage bolts in each corner. Under each 60" board are bolted two castering wheels (200# capacity each), 14" in from each end (32" from wheel to wheel). The vertical portion consists of four 84" long 3/4" rigid galvanized pipes, fashioned into a pyramid. At the bottom, each of the pipes lines up directly over one of the casters, with a little counterbore into the wood to keep it in place. At the top, I cut four pipe couplings (the above dimensions work this out to be 18 degrees) and welded them to a 4" square by 1/8" thick plate. In the middle of this plate is a hole for an eye bolt. I really like the fact that when I'm not using it, it can be disassembled for storage. The base is sized to straddle the engine pallet. This size lift will easily put the top of the engine at about 48" above the floor with a typical come-along, so size it as necessary for your application.
RV-List message posted by: "Randall Henderson" <randallh@home.com>
> How can you tell a good dimple from a bad one? My dimples are the right
depth for my rivets. What other criteria are there for 'goodness' in dimpling?
Look for a "fisheye" (distorted area) around the dimple. This can happen if you
over-dimple and stretch the skin, or under-dimple and don't bottom out the die.
If it's right, the skin will be flat right up to the dimple. To detect this,
move it around under the light until the light source is reflecting right at
the dimple.
Flush riveting in critical areas requires new techniques. The shin must be preapred so that when a 100degree flush rivet or screw is installed, a smooth skin surface is maintained. On heavier sections this can be accomplished by machine countersinking, on thinner materials by dimpling.
MICROSTOP COUNTERSINK CAGE
The countersink cage is faster and produces a more accurate, uniform countersink. It is adjustable in .001" steps for different cutting depths. It consists of a footpiece, locking sleeve, locknut, and spindle.
The Countersink must be adjusted by trial and error. Start with athe countersink cutting shallow. Test depth of cut with a rivet. Always check your countersink depth setting on scrap. Continue adjusting and testing until the proper depth is reached. Two or three consecutive good holes should be produced before moving to the airplane. Countersink all holes as required. Check depth of countersink holes frequently.
Hold the countersink at 90degrees to the material.
Hold the Locking Sleeve firmly; do not allow the footpiece to spin against the metal.
RV-List message posted by: smcdaniels@juno.com (SCOTT R MCDANIELS): The machine countersink required for a flush (AN426) rivet to fit flush, and the countersink for a dimpled skin to fit flush are 2 different depths. If you simply use the countersink cage that you have set for rivets the skin will not lay down flush. The depth of countersink required for a dimple somewhat depends on the thickness of the material that is dimpled (and it is the materials thickness that requires the countersink to be deeper). In the shop at Van's we have a bunch of what we call test patches. Little scrap pieces of aluminum with a 45 deg. bend in them. They have different sized holes in them (for rivets and screws) that have been dimpled. The 45 deg. bend provides a handle to let you test fit the dimple in a countersink when adjusting the countersink cage. You can make a few of your own to use when you have to machine countersink for a mating dimpled part or skin.
RV-List message posted by: Alex Peterson<alexpeterson@MCI2000.com>: To drill straight holes through three pieces that are separated by a half inch or so, drill holes in some hardwood blocks. Drill one of the three pieces, clamp the blocks in between the various layers, and drill.
RV-List message posted by: wntzl@execpc.com (David M Wentzell): Dimpling Table
for Avery Dimpling Tool: Top is 18 x 52 (not important). Channel down the
middle is 4x18x2.25 which allows the tool to slide front to rear. At the far
rearward position it must be supported by a leg (separate item, 2x4 with a U at
top to hold the free end). As I move the tool back, I fill the chanel with
precut filler blocks to keep the flat surface & prevent "accidents". I then
lay 3/16 foam core over the complete top surface to prevent scratches, with
that, the die surface is then at table height. Table height is also same as the
main work table so that when working at left end, right end is supported by
main work table & vice versa. Legs & channel base support are 2x4, top
is 3/4 plywood, as is channel and filler blocks. Nothing fancy here but it does
work very nicely. If anyone wants to do this and wants more info I can probably
explain better over the phone.
================== Drill Size versus Diameter ===================
Size Inch Size
Inch Size
Inch Size Inch
---- ------ ----
------ ---- ------
----- -----
80 .0135
32 .1160
M .2950 15/16 .9375
79 .0145
31 .1200 19/64
.2969 61/64 .9531
1/64 .0156 1/8
.1250 N
.3020 31/32 .9688
78 .0160
30 .1285 5/16
.3125 63/64 .9844
77 .0180
29 .1360
O .3160
76 .0200
28 .1405
P .3230
75 .0210 9/64
.1406 21/64 .3281
74 .0225
27 .1440
Q .3320
73 .0240
26 .1470
R .3390
72 .0250
25 .1495 11/32
.3438
71 .0260
24 .1520
S .3480
70 .0280
23 .1540
T .3580
69 .0292 5/32
.1563 23/64 .3594
68 .0310
22 .1570
U .3680
1/32 .0313 21
.1590 3/8 .3750
67 .0320
20 .1610
V .3770
66 .0330
19 .1660
W .3860
65 .0350
18 .1695 25/64
.3906
64 .0360 11/64
.1719 X .3970
63 .0370
17 .1730
Y .4040
62 .0380
16 .1770 13/32
.4063
61 .0390
15 .1800
Z .4130
60 .0400
14 .1820 27/64
.4219
59 .0410
13 .1850 7/16
.4375
58 .0420 3/16
.1875 29/64 .4531
57 .0430
12 .1890 15/32
.4688
56 .0465
11 .1910 31/64
.4844
3/64 .0469 10
.1935 1/2 .5000
55 .0520
9 .1960 33/64
.5156
54 .0550
8 .1990 17/32
.5313
53 .0595
7 .2010 35/64
.5469
1/16 .0625 13/64
.2031 9/16 .5625
52 .0635
6 .2040 37/64
.5781
51 .0670
5 .2055 19/32
.5938
50 .0700
4 .2090 39/64
.6094
49 .0730
3 .2130
5/8 .6250
48 .0760 7/32
.2188 41/64 .6406
5/64 .0781
2 .2210 21/32
.6563
47 .0785
1 .2280 43/64
.6719
46 .0810
A .2340 11/16
.6875
45 .0820 15/64
.2344 45/64 .7031
44 .0860
B .2380 23/32
.7188
43 .0890
C .2420 47/64
.7344
42 .0935
D .2460
3/4 .7500
3/32 .0938 1/4
.2500 49/64 .7656
41 .0960
E .2500 25/32
.7813
40 .0980
F .2570 51/64
.7969
39 .0995
G .2610 26/32
.8125
38 .1015 17/64
.2656 53/64 .8281
37 .1040
H .2660 27/32
.8438
36 .1065
I .2720 55/64
.8594
7/64 .1094
J .2770
7/8 .8750
35 .1100
K .2810 57/64
.8906
34 .1110 9/32
.2813 29/32 .9063
33 .1130
L .2900 59/64
.9219