Les Henson Posted November 13, 2007 Share Posted November 13, 2007 How do you scribe a perfect circle around a pipe (to cut it cleanly)? Les. Quote Link to comment Share on other sites More sharing options...
discojmz Posted November 13, 2007 Share Posted November 13, 2007 tbh i usually just cut it with something i know is going to cut it square simplest other way i found was use a wide jawed pipe cutter, not to cut it, just to run around and scribe the line round it sorry if that's no help at all Quote Link to comment Share on other sites More sharing options...
landrover598 Posted November 13, 2007 Share Posted November 13, 2007 I cut up a cereal box with one straight edge, wrap it tightly around the pipe, line up the straight edge where the ends meet, and draw along that edge. Quote Link to comment Share on other sites More sharing options...
alan kemp Posted November 13, 2007 Share Posted November 13, 2007 I cut up a cereal box with one straight edge, wrap it tightly around the pipe, line up the straight edge where the ends meet, and draw along that edge. As above but I use a piece of A3 paper and an indelible marker. Make sure both sides of the paper are in line or it will not be square. Quote Link to comment Share on other sites More sharing options...
SiWhite Posted November 13, 2007 Share Posted November 13, 2007 I use a wide strip of masking tape - usually good enough... Quote Link to comment Share on other sites More sharing options...
Tonk Posted November 13, 2007 Share Posted November 13, 2007 what size tube are you cutting? if its got to be perfect can you not face it off on a lathe afterwards? Quote Link to comment Share on other sites More sharing options...
LandyManLuke Posted November 13, 2007 Share Posted November 13, 2007 a new sheet of A4 paper normally does the trick. Quote Link to comment Share on other sites More sharing options...
T1G UP Posted November 13, 2007 Share Posted November 13, 2007 We use a wrap a round. 100mm wide rubber conveyor belt!Last for ever. Quote Link to comment Share on other sites More sharing options...
Les Henson Posted November 13, 2007 Author Share Posted November 13, 2007 I'm going to cut and shut a prop. I don't a lathe I'm afraid. Les. Quote Link to comment Share on other sites More sharing options...
Daan Posted November 13, 2007 Share Posted November 13, 2007 I used a large pipe cutter for this, bought cheaply on ebay. I'm going to cut and shut a prop. I don't a lathe I'm afraid.Les. Quote Link to comment Share on other sites More sharing options...
will_warne Posted November 13, 2007 Share Posted November 13, 2007 How about placing one end up against a vertical surface and the rolling the tube in a peice of angle clamped the the bench? You can then sit the scribe / pen nib up against one side of the angle. Alternativly speak to someone who owns a saw that'll chop at 90* nicely Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted November 13, 2007 Share Posted November 13, 2007 Clean sheet of A4 Paper and some making tape. Run the paper around with an "Edge" of the paper where the cut is to be Then overtape the paper with masking tape, ie part on the paper part on the tube. GENTLY hacksaw the joint between paper and tube, do a little bit and then rotate and continue around the tube untill all the wat around, then remove paper and tape, and the tube is scribbed all the way round properly Then cut to the line made job done Nige Quote Link to comment Share on other sites More sharing options...
Turbocharger Posted November 13, 2007 Share Posted November 13, 2007 Les, the way I've seen this done is to lop your prop in half as square as poss, chop out the requisite amount to shorten and then bash an offcut of tight-fitting tube down the inside of the prop. Slide the other half of the prop on, hold Will's pigeon above and tickle to taste while the inner pipe holds it square. Quote Link to comment Share on other sites More sharing options...
T1G UP Posted November 13, 2007 Share Posted November 13, 2007 If it's for shortening props then we've got a lovely GF that'll cut up to 4" and it does it SQUARE. Quote Link to comment Share on other sites More sharing options...
Les Henson Posted November 13, 2007 Author Share Posted November 13, 2007 Why not sleeve it on the outside? weld the two halves back together, clean off any weld that's greater than the diameter of the prop, slide the sleeve over the cut and then weld it? 3-welds are better than 1 I would have thought. Les. Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted November 13, 2007 Share Posted November 13, 2007 Why not sleeve it on the outside? weld the two halves back together, clean off any weld that's greater than the diameter of the prop, slide the sleeve over the cut and then weld it? 3-welds are better than 1 I would have thought.Les. NEITHER When I have done this I have cut CLOSE to the Yoke, then you can find that the yoke has a male end which can be reshoved back into the now shorthed tube its a super snug fit, and this way you get the straightness with a bit a BFH Tickling Nige Quote Link to comment Share on other sites More sharing options...
SiWhite Posted November 13, 2007 Share Posted November 13, 2007 Les, I've got a lathe and a power hacksaw - open invite to use either if you ever need..... Quote Link to comment Share on other sites More sharing options...
Astro_Al Posted November 13, 2007 Share Posted November 13, 2007 There are a million ways to get it straight - just clamp the two into some angle iron/I-beam/V-blocks for an easy one. Cut it any way you want. Then use your nice sheet of paper to mark a straight edge on each half, then grind down to the line - that'll get you close enough to perfect that your weld will cope with any minor imperfections. The straightness of the cut edge is only important if you're relying on the contact angle between the two halves to create the straightness. Better to ignore that angle (since its offset from the axis is small) and align the two bits lengthways - less error prone. Since you're now not worrying about the contact surface being straight, you can also chamfer round the end of each bit to help the weld, if you need to. You're far more likely to pull it off straight when you weld up one side and it pulls as it cools, than by failing to line it up ok in the first place. So make sure you tack it and clamp it up nicely to avoid distortion and it should be straightforward. Al. Quote Link to comment Share on other sites More sharing options...
BIG DAN T Posted November 13, 2007 Share Posted November 13, 2007 put a hose clip around it. Quote Link to comment Share on other sites More sharing options...
Tonk Posted November 15, 2007 Share Posted November 15, 2007 NEITHERWhen I have done this I have cut CLOSE to the Yoke, then you can find that the yoke has a male end which can be reshoved back into the now shorthed tube its a super snug fit, and this way you get the straightness with a bit a BFH Tickling Nige thats the way i always do it, be sure to remove the seam on the inside of the tube before reassembly Quote Link to comment Share on other sites More sharing options...
Guest diesel_jim Posted November 15, 2007 Share Posted November 15, 2007 I'm going to cut and shut a prop. I don't a lathe I'm afraid.Les. Les, when i've shortened propshafts, i just use one of those "cut off" machines, like an angle grinder mounted on a hinged pivot with a vice type thing to clamp the work in. we use them at work for chopping off conduit, and funnily enough, i happen to have one at home.... want me to drop it off? Quote Link to comment Share on other sites More sharing options...
Les Henson Posted November 16, 2007 Author Share Posted November 16, 2007 Just planning ahead and gathering information Jim. Thanks and I'll take you up on your offer in the near future. Les. Quote Link to comment Share on other sites More sharing options...
upnover4x4 Posted December 7, 2007 Share Posted December 7, 2007 I usually use a jubilee clip suitably sized. Tighten it fully & cut with grinder cutting disc or hacksaw Quote Link to comment Share on other sites More sharing options...
Guest mortus Posted December 17, 2007 Share Posted December 17, 2007 wouldnt the use of a mitre saw with a hack saw blade solve all of this? correct me if im wrong, and completely not understanding this thread. Quote Link to comment Share on other sites More sharing options...
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