Presentation on theme: "Disclaimer Not how but why Options"— Presentation transcript:
1Disclaimer Not how but why Options Types of DovetailsDisclaimerNot how but whyOptions
2Dovetail Discussion Partially housed, tapered mortise and tenon joint Cousin of box joint (see drawing)Old jointStrong jointMechanical jointIncreases glue surfacesDirectional jointExposed vs. non-exposedStart and end with pin or tail (?)Symmetrical vs. AsymmetricalStrengthProportions (size)DecorativeSelf aligning and squaringSign of craftsmanshipLearning curveTime involvedEasy to fix mistakesSingle use or variety of useEliminates the use of mechanical fasteners (except dowels)Angles of dovetailsNot just furniture/cabinetmakingTimber framingMetal workMasonryMachinery
3Angle of dovetailGenerally expressed as ratio (rise/run)– not in degrees1:6 for softwood (9.5 degrees)1:8 for hardwood (7.1 degrees)1:4 for thin stock (14 degrees)Hardwood/softwood mixed?Old furniture vs. new dovetailsRouter bits for machine cut dovetails – 7 to 14 degrees commonMarking gauges for dovetails (manufactured and shop made)Personal preference – looks
6Common dovetail bits by two manufacturers. Angle vs. depth of cutNotice the range in the angles.Must allow room for shank of router bit.
7Dovetail BevelTo find the angle draw a line square with the edge of a board and divide it into 6 or 8 parts as desired; from the end of the line and square with it, mark off a space equal to one of the divisions and set the bevel as shown.
8Dovetail MarkerManufactured dovetails markers mostly cover 3 common sizes.Shop made dovetails markers can be customized.
9Full/Through Dovetails Hand cut vs. machine cut vs. template cutDirectional – be aware of forcesExposed vs. non-exposedThickness of woodSpecies of wood (fibers)Symmetrical vs. AsymmetricalNumber of tails – even vs. oddProportions of tails and pinsSize of pinsHalf pin vs. half tail at topProud vs. flushUndercut vs. square cutLong grain vs. end grain glue surfaceIdentify Tails or Pins by looking at the face of the board.
10Full/Through Dovetail From Audell ‘sShop Manual1923.Dovetails are a dying art? 1902
11Half Pin vs. Half Tail Dovetail StrengthLocation of groove for insertPersonal preference
12Beveled DovetailsA full/through dovetail where one of the boards are at an angle other than a right angle.Common on tool totes.Use a “wedge” with marker to layout dovetails.
13Compound DovetailA full/through dovetail where both of the boards are at an angle other than a right angle.Common on serving trays.
14Lap Dovetail Lap joint in the shape of a dovetail. Can be full lap or half lap dovetailCan be blind or throughCommonly used where the top drawer rail meets the legLimitations?
15Sliding Lap Dovetail Directional Cross grain Half or full lap Can be used to allow for movement
16Bridle DovetailLike a bridle joint except the insert is dovetail shaped instead of rectangular.Mortise and tenon vs. bridle joint.Directional - only on exposed ends of boards.
17Used in place of a butt joint. Dovetail Scarf JointUsed in place of a butt joint.
18Half Blind Dovetail Joint hidden from front Tails on side fit into sockets on frontDirectionally strongTimeBe aware of directionCommonly used in drawers and cases
19Full Blind/Double Lap/Secret Dovetail Joint hidden from front and sideAlso called hidden or secret dovetail jointMolding of furnitureVeneer work?TimeHides joinery and craftsmanship
20Blind Mitered Dovetail Top pin is miteredSame as full blind except lap is miteredTimeHides dovetailsStrong exposed miter joineryEliminates cuppingFurniture
21Mitered Through Dovetail Top pin or tail is miteredRest of dovetails are throughCommon on tool chests, serving traysAnywhere the top rail is prominent
23Sliding/Housed/Tapered Dovetail Dovetailed shaped dadoCross grain - be aware of expansion of woodSlides through – directionalCan be parallel or taperedStopped or throughHand cut vs. template cutShelves and dividers
24Half Sliding/Bareface Dovetail One side is square and the other is dovetailedCan be taperedStopped or throughUsed when board is too thin for dovetails on both faces - strengthCommonly used in pigeon holes of desks and secretary
25Diminished Dovetail Cross between dado and sliding dovetail Always a stop jointDirectional
26Tensioned DovetailDovetails are narrow at edges and progress to wider in middleMakes joint stronger at edgesSaves timeLooks interestingLarge chests
27Modified Tensioned Dovetail More artistic than functionalStronger at ends but balanced proportions
28Decorative Dovetail (Hounds tooth) Many unique dovetails fit this categorySometimes cut in an arc shapePins and tails can be shaped differentlyOpportunity to set your own style
29Hounds Tooth Dovetail in progress Note small sized pinsPins set inside dovetailOff set at top of pin board
30Doweled Dovetail Dovetails for strength Dowels are quicker and added for strengthInteresting look
31Double Dovetail Made famous by Incra Through or half blind Usually contrasting species of wood to highlight joineryCan be cut by hand – usually with contrasting wedges installed in kerfs at jointsDecorative boxes
32Hand Cut Double Dovetail Contrasting wood to accentuate the double dovetailInteresting lookTwice the time
33Dovetail Keys and Splines Align cross grainPrevent warping and bowingAllow cross grain movementReinforce jointDecorativeQuick and easyBoxes
34Dovetail Inlay - Dutchman Inlay dovetail (bowtie) shaped piece of wood to hold split from opening up moreUsually contrasting piece of woodAccentuates a flawDecorative
35Other Dovetails??Comments on other unusual dovetails?
36Questions or Comments? Suggestions? You should be aware of the many different kinds of dovetails and their uses. This needs to include the strengths and weaknesses of each joint, so the next time you can determine the correct dovetail for your specific application. With knowledge, skill and experience you can alter or design your own style of dovetail joints!Questions or Comments?Suggestions?