• For most air tools used to build an airplane kit a 2 to 5 H.P. portable piston type air compressor is adequate. The main consideration is the CFM (cubic feet per minute) rating of the compressor. Most air tools will use 4 to 5 CFM at 90 PSI under continuous use. You will want a compressor that supplies a minimum of 5 CFM at 90 PSI. (Note: some compressors give CFM ratings at lower PSI pressures -- don't be fooled by a 4 or 5 CFM rating at 30 or 40 PSI). Also pay attention to the wattage or current draw of the motor -- a more energy efficient motor will pay for itself over the life of the project. Consider a 220 volt motor if electric service is available in your shop. If you plan to paint your airplane, and for continuous use tools (die grinders, sanders, paint guns) get a larger (6-8 CFM) compressor to avoid running out of air, waiting for pressure recovery, and over-heating the compressor. A special consideration here: Air compressors are designed to run a cycle and be off a sufficient time to avoid over-heating of the compressor cylinders, pistons, oil, valves, etc. If you get too small a compressor and run it continuously, it will over-heat, wear out quickly, and contaminate your air hoses and tools with burned oil and carbon particles, air hose rubber particles from deteriorating hoses, etc. (I've repaired a lot of air tools over the years and seen it all!!). Tank size determines the amount of time the compressor runs to fill up the tank -- so get the biggest tank you have room for. Last, check out how much noise the compressor makes when starting up & running before you buy it. If it's in the garage with you or outside next to the neighbor's bedroom, the noise level might be a big factor.

What tools do I need to build an airplane?

• It is best to refer to the building manual provided with your kit. It should provide a recommended tool list. If you do not locate the list, check with your kit supplier. We have designed our RV toolkit using the Van's Aircraft list. This list can be found in the beginning of our catalog. Stoodard Hamilton provided us with a recommended tool kit package for the Glastar, and this suggestion is available as the "Glastar Tool Kit".

Do I really need all of that?

• No, you do not absolutely need every item included in the lists; however you should try to have all of the tools the kit manufacturer recommends. Remember -- not having the right tool for a job can make the task much more difficult and time consuming, and may result in added frustation and sub-standard results. First, look around your shop -- you may already have a few of the tools needed. You could start with the basics -- a rivet gun, a few rivet sets, a bucking bar; and add the rest of the tools as you find a need for them and can afford them. Keep in mind that our catalog and the tool kits are full of items that are great time-savers and frustration-preventers. The best advice is to go out and talk to people who are building or have built a project like yours, and see what they experienced. Even better, think about taking a weekend sheetmetal course.

Which rivet gun do I need, a 2X or 3X?

• Both the 2X & 3X guns will set 3/32" & 1/8" rivets. The 2X gun has a shorter stroke and shorter (lighter) piston, and hits more blows per minute -- the blows are lighter than a 3X, thus it takes longer to set a rivet with a 2X gun. The 3X gun has a longer stroke and longer (heavier) piston, and hits fewer blows per minute -- the blows are heavier than a 2X, thus it takes a shorter time to set a rivet. Keep in mind you can regulate your air pressure up or down to make either a 2X or 3X gun hit harder or lighter. Suggestion: Contact other builders in your area and try out both a 2X & 3X gun -- choosing a rivet gun can come down to a personal preference of how a particular gun feels to each individual.

Can I use an "air hammer/chisel" in place of a rivet gun?

• Air hammer/chisel guns are designed for hitting hard and do not have a teasing trigger like a rivet gun. The results will not be good. Suggestion: Find another builder in your area with a real rivet gun -- set some rivets with a real rivet gun and some with a muffler cutter and compare the results.

What size air compressor do I need?

• For most air tools a 2 to 5 H.P. portable compressor is adequate. Check the CFM (cubic feet per minute) rating of the compressor. Most air tools (drills, die grinders, rivet guns) are rated from 2 to 6 CFM for continuous use. Keep in mind that you will not be drilling or riveting for long periods so the compressor will not need to run continuously. The exception is if you plan to paint your airplane -- get a compressor big enough to supply continuous air supply for the paint gun you plan to use. 

What kind of benchtop grinder do I need?

• The only use for a benchtop grinder would be for mounting a Scotchbrite wheel to deburr parts. The wheels have a 1/2" thru-hole X 1" width X 6" diameter.

What drillpress do I need?

• A bench model drill press is adequate for most application. One with variable speeds (step pulleys) will be more useful. Consider mounting your Scotchbrite wheel on an arbor in the drill press. This gives you more access to the wheel (than on a bench grinder with a guard) + the horizontal location of the wheel makes edge deburring of large pieces (such as wing skins) easier.

Can I use my cordless drill instead of an air drill?

• Yes, cordless drills are fine. Their rpm is slower but cordless drills work fine for hole drilling, countersinking, etc. Note: sometimes the slower speed of a cordless drill is an advantage for countersinking (the slower speed reduces the chances of the cutter chattering in the hole).

Which squeezer, Tatco or Avery?

• The Tatco squeezers are good, light duty squeezers. The deepest (largest) yoke available for a Tatco is 3" deep. Tatco yokes are only available from a Tatco source and no other yokes will interchange with Tatco Squeezers. The Avery squeezers are heavier duty and use the standard CP-214 style pneumatic squeezer yokes that are standard to the aircraft industry, and are available from any aircraft tool supplier. More sizes of yokes are available for the Avery squeezer -- up to 4" deep, +(3) sizes of no-hole yokes, & a longeron yoke. Consider starting with the Avery hand squeezer and if you ever decide to up-grade to a pneumatic squeezer; all you need to buy is the squeezer body, as all of the yokes you have will fit on either the hand or pneumatic squeezer.

Do I need (have to have) a pneumatic squeezer or a hand squeezer?

• For dimpling and flush riveting a hand (or pneumatic) squeezer is a necessary tool to have. Hand squeezers are adequate for most builders to build with. If you have problems with repetitive motion or stiffness of the finger joints, consider a pneumatic squeezer as they are easier to use and put less stress and wear on the hands. (Ask fellow builders that have pneumatic squeezers their opinion and most will say it's the best, most useful tool they ever bought).

How do I set/ adjust squeezers for different length rivets?

• Hand squeezers have adjustable set holders (the part that moves up & down when you move the handle). These set holders are internally threaded and screw up & down to give you a range of adjustment. Pneumatic squeezers have a rigid set holder and you adjust the die height by adding shim washers of different thickness, and / or use different height flat set holders. (Note: we make an adjustable set holder for pneumatic squeezers that works the same as the set holders on hand squeezers).

How do I change squeezer yokes?

• On the Tatco hand squeezers there are (3) 1/4" roll pins that you drive out with a hammer & punch to change yoke. (You could replace these roll pins with bolts or quick release pins). On Avery hand squeezers we use (2) quick release pins for easier / quicker yoke changes.

What is a fluting plier ?

• Fluting pliers are used to straighten ribs flanges and to form curved stringers. The jaws of the fluting plier form the metal in a fashion that "shrinks" a small section of a flange; as a small area is pushed down it pulls the adjacent material into the bend. When this is done close together you end up with a curved section of material -- a quick & neat way to make a curved stringer. Note: Our fluting pliers are capable of forming a flute about 1/2" wide -- so you can do a lot of fluting in a small section. The type of fluting pliers that have molded plastic jaws make a flute about 3/4" to 1" wide and do not work as well when trying to form curves and / or missing rivet spacing.

Measuring tips for AN bolts

• Do AN bolt length "--numbers" confuse you?? Here is the secret to how to measure bolt lengths with a scale. AN BOLT LENGTHS ARE MEASURED IN INCREMENTS OF 1/8". Example: a -4 length is 4-8ths, or 1/2"; a -6 is 6 - 8ths, or 3/4"; & a -7 is 7/8". Note that after a -7 the next size is a -10; this bolt would be 1" long. At 1" the 2 digit -- numbers start. You now read the first number as full inches & the second number as fractions of an inch in 1/8ths. Example: a -13 length is 1 & 3/8"; a -25 length is 2 & 5/8"; a - 34 length is 3 & 1/2". Note this length is measured from under the bolt head to the end of the threads. Also, note that bolt diam-eters are measured in 1/16ths. A -3 diameter is 3/16"; & a -4 dia. is 4/16 or 1/4". SIMPLE GRADE SCHOOL FRACTIONS !!!!!!

Punch use tips

• If you have a rivet that will not go in a hole, use a punch to align holes in mating parts - just insert the punch in the hole and twist around in a circular motion and this will pull the parts together in alignment. If the rivet is still tight, you can repeat with a little more circular force and the punch motion will actually enlarge the hole slightly -- (practice this slowly so you don't oversize the hole).
  When removing rivets drill into the rivet head to a depth equal to the height of the head (caution - any deeper may damage the hole in the part) and use a punch the size of the drill to break or snap off the rivet head; then drive the rivet shank out with the punch. You may need to back up the rivet when punching it out -- a simple method is to use a block of wood or plastic with a drilled hole large enough for the rivet shank to fall into. The block supports the area around the rivet + does not mar the surface; however, this may take an extra hand to accomplish.

Drilling tips : Strap duplicators

• Always use a drill stop on your drill when using a strap duplicator. Preset the drill depth to avoid drilling into the bottom part of the strap duplicator. (The guide pin piece is not hardened). Repeated drilling into the bottom part will eventually drill thru and cause the guide pin to fall off and will ruin the strap duplicator.

Drilling tips : Nutplates

• For nutplates first drill a clearance hole for the screw (should be the same size as the large pin on the nutplate jig). Locate the jig with the large pin in hole (both a small & large pin will be sticking up). Drill the first rivet hole with a #40 drill. Flip over the jig and insert the large pin in the clearance hole and the small pin in the first rivet hole just drilled. Drill the second rivet hole. Deburr & countersink holes and install nutplate. In a pinch, you can use a nutplate for a drill jig, Use a short screw or cleco to hold the nutplate in position; drill the first rivet hole; temporarily use a rivet to maintain the first hole location; then drill the second hole. Deburr, countersink, etc.

Helpful metal cutting tips

• Most metal snips leave marks on the edge of the material - some worse than others if the cutter jaws have serrations to grip the work. One way around this is to not cut directly on a finish line, but to cut about 1/16" away from the finish line. This serves two purposes - first it makes it easier to cut without worrying about cutting too deep or staying on a straight line; second, the marks made by the snips will be removed so they are not a problem. Use either a vixen file to finish the edge down to the line; or use coarse emery cloth (about 60 grit works fine) attached with staples or tacks to a straight board about 12" to 18" long. This sanding block will take the high spots down quickly and leave you with an unmarked straight edge, (no snip marks). Be careful as the edges will be sharp until you deburr.

Helpful deburring tips

• The Scotch-brite wheels listed above are primarily for deburring edges of aluminum sheets. The wheels cut too much to be used on the surface of a skin (the surface conditioning product are for that use). It is a good practice to first deburr the edges of aluminum sheets & parts with a hand scraping tool (such as our #1043 swivel deburr or our #1044 double edge tool). On the ends of angles and other parts it would be good to belt sand or roughly file & roughly radius all sharp corners & edges. Your wheels will last longer and wear down less quickly if you take this step before running the parts against the wheel. The Scotch-brite wheels can be dressed down when needed by carefully running a sharp steel object (needs to be supported as rigid as possible) against the edge of the wheel while the wheel is turning. Note that whatever you use (old file, chisel, etc.) will be cut down, so don't use anything you do not wish to be dulled or cut down. Above all, be extra careful & wear eye protection when dressing wheels - it's messy!!

Hole reaming tips

• Always use a lubricant when reaming holes. Use a slow turning drill (electric of cordless drill). Start with about a 1/32" undersize hole and finish ream to the desired hole size. Hold the drill and reamer square. To make a temporary drill or reamer guide for holes in parts that cannot be taken to a drill press, first drill or ream a guide hole in a block of mate-rial (wood, aluminum, plastic, etc.) and clamp the block onto your work -- you now have a true & square hole guide.

Bucking bar tips

• Bucking bars come in many shapes and sizes. Generally the heavier the bar, the better the bar works for upsetting the shop head side of the rivet. Also, the larger the working face size; the less chance you will slip off the face and damage the work or rivet. Most bucking bars have two surfaces polished to set rivets on, and the rest of the bar will be a rough cast finish. You can get extra versatility out of a bar if you belt sand and polish some of the other cast surfaces -- usually a side, edge, or opposite end. Use a belt sander first, and then a Scotchbrite wheel to finish. In a pinch, you can use any steel object as a bucking bar -- look around your shop & tool box and you will usually find a tool or part that will work as a bucking bar (does not need to be heat treated if just used for a few rivets).

Helpful riveting tips

• When riveting with a universal rivet set you may experience marks on the head of the rivet from time to time. An old riveting trick is to put one or two pieces of masking tape on the end of the set (sticky side into the cupping) and this will usually help cushion and protect the rivet head. Note the tape will have to be replaced every 4th or 5th rivet as the tape wears out. Also, a piece of masking tape put on the face of a flush rivet set will keep the set from leaving black marks on the surface of the work. This tape will have to be replaced periodically when it wears through.

Helpful air tool tips

• Air tools should be oiled daily when in use with a non-detergent type oil . We recommend 4 or 5 drops of air tool oil, or Marvel Mystery Oil, through the rear air inlet of the tool. If possible, a fog type oiler is recommended. Check your air compressor daily for excess water, and drain as necessary. Moisture greatly affects and reduces tool life and efficiency. 120 P.S.I. is maximum satisfactory pressure for most air tools, consult the mfg. specifications. Store your air tools in a clean and dry place when not in use. Also, cover air inlets and rivet gun barrels to keep bugs and foreign matter out. Lubricate and run air tools frequently to avoid corrosion and gumming of lubricants.

What is the difference between a 2X / 3X / 4X rivet gun ?

• The only outward difference is that the 3X gun has a barrel about 1/2" longer than a 2X gun. Inside, the 3X gun has a longer stroke and a heavier (longer) piston; thus it hits fewer strokes per minute but is harder hitting than a 2X gun. The 2X gun has a shorter stroke and a lighter (shorter) piston and while it hits more blows per minute (because of the shorter stroke) the lighter piston does not hit as hard, thus it is easier to control. Either the 2X or 3X guns will work for setting 3/32" and 1/8" rivets and the air pressure used can be adjusted up or down to each individuals liking to make either gun seem to hit harder or softer. Note the 4X gun is just bigger (longer) than a 3X gun and has a 1/4" rivet capacity.
  Tip: Check with local builders / mechanics and try out the different size guns before you order.

What size hand squeezer do I need ?

• Hand rivet squeezers are used for setting rivets around the edges of parts and for dimpling rib & spar flanges. By squeezing the handles together by hand, force is applied through leverage to an adjustable set holder that squeezes dies together to set a rivet or dimple. Hand squeezing 1/8" & larger rivets takes considerably more effort than dimpling, and rivets larger than 1/8" are normally set with a rivet gun.
  In most instances, a 1-1/2" or 2" yoke squeezer is all you need since most rib & spar flanges are less than 1" wide. Anything further in can be done with a rivet gun & bucking bar. With a squeezer that has removable / replaceable yokes, you could add a larger yoke if & when you find a need for one later during your project.
  You could choose a large yoke to start with, say a 3" yoke. This would give you the flexibility to do flanges as well as reach rivets up to 3" in from the edge of parts. The only disadvantage to the larger yokes (beside the added cost) is that they are bigger, heavier, and the larger yokes flex open a little when squeezing 1/8" rivets. (Yokes larger than 3" tend to flex or spread open enough to change the alignment between the dies and this makes setting rivets much more difficult, if not impossible to set - - better results are usually obtained with a rivet gun & bucking bar).

What is a hand seamer ?

• Hand seamers are used like a hand held bending brake. You can bend small flanges, straighten flanges, bend tabs in different directions, etc. with a hand seamer. For aircraft work make sure you get a hand seamer that has a radius on the edge of the jaw so you don't bend too sharp of a radius and scratch or mark the inside of the bend radius -- (both are bad practices for aircraft as fatigue cracks can result). Note that most welding & duct-work seamer pliers have too sharp of an edge for aircraft work and their jaws may be too thin to grind or modify with a radius for aircraft work.

What are "Spring back dimple dies" ?

• Spring back dimple dies are dies with a special angle machined on the faces of both dies. The male dimple die has a concave angle (negative taper) of about 1 degree on its surface, and the female dimple die has a convex angle (positive taper) of about 2 degrees to its face. This angle causes the material being formed to bend slightly upward (over-bend) during forming as the dies are pressed together and bottom out. After dimpling the surface "springs back" to a flat surface to give a better and smoother finish. This slight amount of taper on the dies is not much but it makes a big difference in the surface finish after riveting. (The skill & experience of the riveter / bucker make an even bigger difference, also).
  Note that due to the (negative) taper of the male die, you will experience a faint / slight marking on the top surface of the part being dimpled, about the size of the diameter of the die. This marking is not deep enough to cause any problems. This slight marking of the surface can be removed with a Scotchbrite handpad in the same manner as you would prepare the surface for painting.