130:
207:
184:
203:. As the extractor is turned, the flutes on the tool dig into the screw, causing it to lock tightly and withstand the applied torque required to remove the screw. A drawback to tapered screw extractors is that their wedge action tends to expand the drilled, and thus weakened, screw. This wedging action can lock the screw even more tightly in place, making it difficult or impossible to extract.
33:
222:, or be sold individually. The screw is drilled out with the appropriate drill and drill bushing. The extractor is then hammered into the hole with a brass hammer, because a steel hammer is more likely to cause the extractor to break. The appropriate special nut is then attached to the end of the extractor. The nuts can then be turned with a
226:
to remove the screw. Straight fluted extractors have less wedging effect than tapered screw extractors, so have less tendency to lock the screws into place. A further form is a parallel fluted extractor, with no taper at all and thus no wedging. These work well, but have the drawback of requiring the
235:
A tool analogous to a screw extractor, but for removing a seized or rounded off nut from a bolt, is a nut extractor, which has tapered, spiral flutes like a screw extractor, but located internally in the tool, not externally. These flutes or grooves grip the rounded nut from the outside, rather than
199:
out to the proper diameter for that extractor. The extractor is then inserted into this hole and turned in the direction opposing the stuck screw's original one, usually using a
227:
pilot hole to be drilled to a precise size. This size is often non-standard for most drill sets, requiring a dedicated drill bit to be supplied with the kit.
272:
325:
299:
116:
346:
50:
195:, for use on right-handed threads, though there are right-handed extractors for removing left-handed screws. The screw is first
97:
54:
69:
76:
83:
236:
being driven into the hollowed out screw shaft and taking hold of it internally as a screw extractor would.
65:
43:
192:
315:
129:
321:
295:
268:
289:
262:
191:
A spiral screw extractor is itself a coarse-pitched tapered screw thread. They are generally
90:
175:, and, if too much torque is applied, can break off inside the screw that is being removed.
351:
219:
206:
183:
340:
215:
17:
32:
214:
Straight fluted extractors may come in a kit that also has associated drills,
200:
239:
Another tool for a stuck nut on a bolt, but not a screw, is a nut splitter.
154:
149:. There are two types: one has a spiral flute structure, commonly called an
165:
169:
223:
205:
196:
182:
172:
146:
128:
291:
Land Rover Series II, IIA and III Maintenance and
Upgrades Manual
142:
26:
317:
Today's
Technician: Basic Automotive Service and Systems
264:
Automotive service: inspection, maintenance, repair
57:. Unsourced material may be challenged and removed.
267:(2nd ed.), Cengage Learning, pp. 62–63,
8:
161:; the other has a straight flute structure.
164:Screw extractors are intentionally made of
117:Learn how and when to remove this message
256:
254:
252:
248:
133:A screw extractor held in a tap wrench
7:
320:, Cengage Learning, pp. 53–54,
55:adding citations to reliable sources
294:, The Crowood Press, pp. 86–,
25:
31:
42:needs additional citations for
145:for removing broken or seized
1:
210:Square flute screw extractors
187:Spiral flute screw extractors
368:
314:Owen, Clifton E. (2010),
347:Metalworking hand tools
288:Hall, Richard (2016),
211:
188:
134:
209:
186:
132:
261:Gilles, Tim (2003),
51:improve this article
212:
189:
135:
18:Extractor (screws)
274:978-1-4018-1234-8
127:
126:
119:
101:
66:"Screw extractor"
16:(Redirected from
359:
331:
330:
311:
305:
304:
285:
279:
278:
258:
122:
115:
111:
108:
102:
100:
59:
35:
27:
21:
367:
366:
362:
361:
360:
358:
357:
356:
337:
336:
335:
334:
328:
313:
312:
308:
302:
287:
286:
282:
275:
260:
259:
250:
245:
233:
181:
139:screw extractor
123:
112:
106:
103:
60:
58:
48:
36:
23:
22:
15:
12:
11:
5:
365:
363:
355:
354:
349:
339:
338:
333:
332:
326:
306:
300:
280:
273:
247:
246:
244:
241:
232:
229:
218:, and special
216:drill bushings
180:
177:
125:
124:
107:September 2022
39:
37:
30:
24:
14:
13:
10:
9:
6:
4:
3:
2:
364:
353:
350:
348:
345:
344:
342:
329:
327:9781111783792
323:
319:
318:
310:
307:
303:
301:9781785001369
297:
293:
292:
284:
281:
276:
270:
266:
265:
257:
255:
253:
249:
242:
240:
237:
230:
228:
225:
221:
217:
208:
204:
202:
198:
194:
185:
178:
176:
174:
171:
167:
162:
160:
156:
152:
148:
144:
140:
131:
121:
118:
110:
99:
96:
92:
89:
85:
82:
78:
75:
71:
68: –
67:
63:
62:Find sources:
56:
52:
46:
45:
40:This article
38:
34:
29:
28:
19:
316:
309:
290:
283:
263:
238:
234:
213:
190:
163:
158:
150:
138:
136:
113:
104:
94:
87:
80:
73:
61:
49:Please help
44:verification
41:
193:left-handed
155:trademarked
341:Categories
243:References
201:tap wrench
153:after the
77:newspapers
151:easy out
197:drilled
170:brittle
91:scholar
352:Screws
324:
298:
271:
224:wrench
159:EZ-Out
147:screws
93:
86:
79:
72:
64:
231:Bolts
179:Types
173:steel
157:name
141:is a
98:JSTOR
84:books
322:ISBN
296:ISBN
269:ISBN
220:nuts
166:hard
143:tool
70:news
53:by
343::
251:^
168:,
137:A
277:.
120:)
114:(
109:)
105:(
95:·
88:·
81:·
74:·
47:.
20:)
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
