topic Re: Two Polylines Won't Join? in AutoCAD Forum

Two Polylines Won't Join?

Anonymous — Mon, 09 Feb 2015 19:06:08 GMT

Hi! I'm new to AutoCAD.

I'm trying to join the two polylines that I have visible in the attached file, but for some reason they just won't. I've tried PEDIT and MPEDIT. I assume this means that they're not quite touching but I can't find the issue. It looks like the shorter one has a line segment on the left end that is causing a problem but I don't know what.

Please help!

Thank you!

Re: Two Polylines Won't Join?

steve216586 — Mon, 09 Feb 2015 19:12:56 GMT

Most likely one or both have a Z value, or Z values which aren't equal. Try FLATTEN. If that doesn't work, I often EXPLODE the plines, FLATTEN and JOIN successfully.

Re: Two Polylines Won't Join?

Patchy — Mon, 09 Feb 2015 19:13:20 GMT

Explode the short one, you have 2 segments at the end.

Re: Two Polylines Won't Join?

Kent1Cooper — Mon, 09 Feb 2015 19:19:10 GMT

The upper-rightward one doubles back on itself -- the place where you want to Join it to the other one is an intermediate vertex, not the end. In PEDIT, select Edit Vertex, hit Enter to see the X marker move around. PEDIT / <select upper-rightward Pline> / Edit vertex / Break / Next / Go / eXit / Join / <select other Pline> <Enter> <Enter>

Re: Two Polylines Won't Join?

HullDrafter — Mon, 09 Feb 2015 19:16:48 GMT

I couldn't get them to join using Pedit either.

However, if you use "Fillet" with a Radius of Zero (0), it does work.

An AuotLISP routine that I got from Dan Abbott's Book "AutoCAD, secrets every usaer should know" helped me to short cut the fillet with zero radius down to two letters "FZ"

(defun c:fz () ;begin fillet zero
(setq old_radius (getvar "filletrad"))
(setvar "filletrad" 0)
(command ".fillet" pause pause)
(setvar "filletrad" old_radius)
)

Hope this helps.

Re: Two Polylines Won't Join?

Anonymous — Mon, 09 Feb 2015 19:28:47 GMT

Thank you everyone! Exploding and deleting the extra line segment worked great.

Re: Two Polylines Won't Join?

Patchy — Mon, 09 Feb 2015 19:38:19 GMT

I agree your way works good until a polyline has a zero length at the end and I missed it.

Re: Two Polylines Won't Join?

Kent1Cooper — Mon, 09 Feb 2015 20:20:13 GMT

@Patchy wrote:

I agree your way works good until a polyline has a zero length at the end and I missed it.

You can tell whether there's a zero-length segment at the end in at least two ways. In PEDIT, in the Edit vertex mode, hit Enter/space to move to the next vertex, and if it starts with a zero-length segment, the X marker won't move the first time, or if it ends with one, won't move between two "stops" at the end. Or in the Properties box, Geometry list, Vertex slot, pick on the left-right arrows to move the same X marker around, and for a zero-length segment, it won't move between two adjacent numbered vertices. If either reveals a zero-length segment, the same PEDIT approach can be used to fix it [or a variant if it's at the end, which would also of course be needed with my earlier suggestion in that case].

If this is a common-enough problem, a routine could certainly be made [there's probably something out there already -- this is at least related] to take any zero-length segment(s) out of any Polyline.

Re: Two Polylines Won't Join?

Anonymous — Tue, 05 Apr 2016 06:09:33 GMT

u can select one of them then move the vertix that u want to join with the other vertix then move it back to it then use join ( click j then enter )

Re: Two Polylines Won't Join?

Anonymous — Mon, 27 Feb 2017 07:10:01 GMT

This is the only method that worked. Thanks 🙂

Re: Two Polylines Won't Join?

Anonymous — Sun, 03 Mar 2019 01:37:55 GMT

it joined my plines but it also distorted my geometry, some times even deleting altogether.

@steve216586 wrote:

Most likely one or both have a Z value, or Z values which aren't equal. Try FLATTEN. If that doesn't work, I often EXPLODE the plines, FLATTEN and JOIN successfully.

Re: Two Polylines Won't Join?

Alfred.NESWADBA — Sun, 03 Mar 2019 06:18:59 GMT

Hi,

>> it joined my plines but it also distorted my geometry

Can you please show the dwg-files, one before the JOIN and a second one after the JOIN? So the next time this happens and after JOIN the geometry has issues then save the drawing, then run undo to the state before the JOIN and save again (well, with a different name).

Also please start command _ABOUT and show us a screenshot from that dialog so we know your exact AutoCAD type and version.

- alfred -

Re: Two Polylines Won't Join?

Anonymous — Mon, 20 May 2019 09:59:52 GMT

Problem is in Elevation.... go to Properties and make both polylines elevation "O" or same value

Re: Two Polylines Won't Join?

binaya.paudelL8YWS — Wed, 31 Aug 2022 15:29:09 GMT

Thanks for your input. Exploding plines and joining helped me.

Re: Two Polylines Won't Join?

n_mirshokraei — Wed, 10 Jun 2026 07:21:52 GMT

type PEDIT and M , then J and join type = both and fuzz distance something rathe

Re: Two Polylines Won't Join?

n_mirshokraei — Wed, 10 Jun 2026 08:04:53 GMT

rather than zero , i go with 0.001 and that works for me