What is a beam compass used to scribe?
a circleThe beam compass is used to scribe a circle, either by drawing with lead, penning by ink, or scratching with a sharpened point. The radius can be adjusted by sliding the metal point holder across a wood beam or metal rod, and locking it by turning a knob at the desired location.
What is the use of compass in drawing?
A compass (or pair of compasses) is a drawing tool that can be used to draw circles or arcs, parts of circles. They can also be used to measure distances, in particular on maps.
Who invented the beam compass?
Morton ToulminPatent Model for Beam Compass Invented by Morton Toulmin. This metal, brass, and ivory U.S. patent model is mounted in a square wooden frame that is painted gold. The trammels are on a 3-1/4" beam that consists of two metal pins and one metal screw.
What is a trammel beam compass?
0:004:48Shop built - beam compass (trammel points) - YouTubeYouTubeStart of suggested clipEnd of suggested clipHey guys did you know a beam compasses a compass with a beam. And sliding sockets or cursors forMoreHey guys did you know a beam compasses a compass with a beam. And sliding sockets or cursors for drawing. And dividing circles larger than those made by a regular pair of compasses. The instrument can
What are the 3 uses of compass?
Uses of a compass A compass helps you to: Know which direction you are travelling in – this is called your heading. Align or orientate your map with your surroundings – setting the map.
What are the two types of compasses used in technical drawing?
There are a couple of variants of drawing compass. A beam compass is made of brass of wooden beam, and it is used for drawing circles that are larger than those made by regular compass. This type of compasses is the most simple by form. The scribe-compass is used by carpenters to scribe a circle instead of drawing it.
What was the compass originally called?
South Pointing FishThe compass was invented in China during the Han dynasty between the 2nd century BC and 1st century AD where it was called the "south-governor"(sīnán 司南) or "South Pointing Fish" (指南魚).
What is a drop bow compass?
Definition of drop bow : a bow compass that permits the center leg to remain stationary while the pen or pencil rotates around the center shaft and that is used especially for drawing small circles.
Why did they invent the compass?
In ancient China, the compass was first used for worship, fortune-telling and geomancy - the art of aligning buildings. In the late 11th or early 12th century, Chinese sailors adopted the compass for astronomical and terrestrial navigation, heralding a new era in the history of navigation.
What is a double pointed compass used for?
Distances can be measured on a map using compasses with two spikes, also called a dividing compass (or just "dividers").
What is the purpose of a trammel?
Trammels are used to measure distance between two points that are too great to be reached with dividers.
What is the difference between divider and trammel?
Trammel heads can be adapted and used for a wide variety of layout tasks. Dividers have fixed metal points and cannot be used with a pencil. The metal points of the tool are used to mark a surface.
Why is compass important?
The invention of the compass made it possible to determine a heading when the sky was overcast or foggy, and when landmarks were not in sight. This enabled mariners to navigate safely far from land, increasing sea trade, and contributing to the Age of Discovery.
What is the main point of a compass?
cardinal direction one of the four main points of a compass: north, east, south, west.
What is compass used for answer?
Compasses are mainly used in navigation to find direction on the earth. This works because the Earth itself has a magnetic field which is similar to that of a bar magnet. The compass needle aligns with the Earth's magnetic field direction and points north-south.
What year was the Dietzgen beam compass made?
The instrument resembles a beam compass sold by Dietzgen in two different grades from at least 1904 to 1934, first as model numbers 646C ($10.70) and 1034C ($6.60) and then as models 927 ($16.75) and 978 ($8.10). The case was lined with silk only in the 1904 catalog description, but the case of pencil leads was not mentioned until 1926. As with many beam compasses, purchasers had to separately buy a wooden bar to connect the trammels, in widths between 5/32" and 3/16" and lengths between 24" and 60".
What is a German trammel?
This German silver instrument has steel and brass points. Two trammels have thumbscrews for fastening to a wooden bar (not included) and for attaching one of the five points. One trammel has a micrometer and is marked on the front: KEUFFEL & ESSER Co. N.Y. GERMANY. The back is marked: PARAGON. Above this mark is scratched: CE1RD. Compare this mark to 1978.2110.02.
What is the number 19 on a trammel?
These thumbscrews are ridged around the edge and have a circular pattern on their tops. The number 19 is engraved inside each trammel. Smaller thumbscrews attach holders for needle and pencil points. These holders have horizontal scrolling but are not identical to each other. Another thumbscrew allows the needle point to be reversed. A micrometer adjustment is below one of the trammels.
How long is a trammel?
This instrument has two very tarnished flat metal bars, each 22 cm long, with tapered ends that interlock to make a beam of 40.9 cm. The two steel sliding trammels resemble pencils and are marked: T.A. & SONS. The longer trammel has a needle point, and the shorter has a pencil point. The shorter trammel has a cam wheel that allows adjustment up to 3/16". Spring tension in both trammels may be adjusted by turning a knurled nut.
How are beam compasses used?
Beam compasses were used to draw circles of large radius by positioning the sliding pieces on a wooden lath. This German silver instrument, also called a draftsman’s trammel, has a smaller sliding piece with a pencil point that may be exchanged for the pen point holder also contained in the case. The smaller sliding piece is engraved with the Kern logo, a K inside a pair of dividers. The larger sliding piece has a needle point. Either end of the needle point may be used.
What are the attachments on a symlink?
The attachments include a pencil point, an adjustable pen point, two steel needle points, and one brass needle point. A rectangular wooden case is covered with morocco leather and lined with green velvet. The bottom of the case is marked: GERMANY.
Where was the beam compass made?
These beam compasses are also similar but not identical to each other. Although this beam compass could not be identified, it probably was made in Germany and dates to the first decade of the 20th century, like the advertised instruments.
Setting Beam Compasses to Radius
I have received many questions on setting a beam compass properly and it is one of the biggest differences between the designs so here is a short review. The compass below has screws labeled A, B, and C in order of adjustment. All beam compasses are set by fixing one trammel and adjusting the other. The adjustable point is always adjusted inward.
Beam Compasses Still in Production
These are still reasonably commonly available. It is not my preferred design but it will work and it will probably be more accurate than a bow compass with an extension bar. I would still check for a used example since these were made in all metal until reasonably recently and they are quite common and inexpensive used.
Beam Compass
A beam compass is used for drawing larger circles or curves larger than what would be possible with small compass sets. A scaled beam is required to carry two trammels found inside small casement. The beam can be of either wood or steel, depending on the workshop where the beam compass is being used.
The Inspiration
Right before Christmas I made a little bird feeder, that needed a plate-like base. I didn't have a compass big enough to properly draw a circle on the board, so I ended up getting a circle cutting jig for my router - and all turned out perfect:
Design and Build
Pretty fancy subtitle for making what has to be almost the simplest possible beam compass, but here we go. Because it's such a thing for me, I searched through some scraps and found the perfect piece!
Esthetics
With that done, that could simply be the end of the project. But I thought I'd give it at least a little bit of a finished look. I started by using a washer to mark out a radius on the ends of the beam.
Finishing
Somehow, pretty much since I first started making homemade tools (which isn't really that long ago), I've been drawn to Minwax Gunstock stain for the "signature" color.
The Collection
And with that, the beam compass is added to the collection of tools made right here at 173! Once again, writing this post took waaay more time to write than it took to make the tool!
Step 1: Cut Two Little Wooden Blocks
Depending from the diameter of the aluminium rod I cut two little pieces of hardwood, a little bit bigger, on my table saw.
Step 2: Drilling Holes
The first block gets a hole for the aluminium rod and a second one for the pencil.
Step 3: Add a Nail
I pushed a nail with a hammer in the pilot hole, cut it with pliers and sharpened it with a file.
Step 4: Assembling
Just put the block with the pencil hole on one end of the aluminum rod
Wide Range Tape Measure Compasses
Extend the blade to draw circles up to 144" diameter. The blade locks in place.
Compass Point-Holding Clamps for Beams
Clamp these point-holding clamps, also known as trammels, onto a beam to create a compass.
Compass Point-Holding Clamps for Rulers
Turn your ruler into a compass by adding these point-holding clamps. They're also known as trammels.
Compass Point-Holding Clamps for Pipes
Combine these point-holding clamps with a pipe to create a compass that marks circles 1 1/2" diameter and larger. They're also known as trammels.
Large-Diameter Layout Compasses
Compasses have spring-tension joints that stay rigid to draw large circles up to 100" diameter. They fold for easy storage.
Starrett Expandable Beam Compasses
Transfer measurements and draw large, precise circles. These compasses have expandable point-holding clamps, also known as trammels, that securely grip the flat top of the beam. Adjust the scribing points with the knurled grip on the clamps. One clamp has a screw for making fine adjustments to ensure accuracy when marking and measuring.
Expandable Beam Compasses
Draw circles up to 24" or add Extension Beams for Expandable Beam Compass to create even larger circles.
