Extruder motor judder

Nearing the point of my first build on a Replikeo Ormerod 2 but I can't get the extruder drive to work. The motor turns the cogs and insert ok with no filament in it, but when I add filament it just stops and the motor/cog judder. I don't even have the tube to the hot head connected. Any ideas what area I should look at or modify to get it to run more freely? The filament is between 1.73 and 1.76 with a pair of calipers so I don't think it's that.

Cheers

First check that with the extruder motor turned off, you can feed filament manually by turning the large gear by hand, in case the filament is catching on something. Then check that you have the extruder motor current set correctly.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Last time that happened to me, the cause was the printed extruder block and it just didnt want to work properly no matter what I did.

So I threw that one away, and printed another extruder block but of a modified design, and it worked like a charm.

With THIS ONE I had your problems.

With THIS ONE forums.reprap.org/ no problems what so ever.

Edited 1 time(s). Last edit at 04/02/2017 07:03AM by Sardi.

Thanks for the advice. When the filament is driven through by hand it leaves teeth marks from the insert on the filament and is fairly stiff to turn. Is that normal?. If I do need a new part, any idea where I can get one made as Replikeo is closing down so they can't give me any support. Catch 22, until I get the printer finished I don't have a way to make parts!

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InventEd
Thanks for the advice. When the filament is driven through by hand it leaves teeth marks from the insert on the filament and is fairly stiff to turn. Is that normal?.

It is normal to leave the marks on the filament, that means that there is contact so that the filament can be pushed through.

What is weird to me is that the original part is causing you problems.. I had problems only with the replacement printed part after the original was worn out.

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InventEd
If I do need a new part, any idea where I can get one made as Replikeo is closing down so they can't give me any support. Catch 22, until I get the printer finished I don't have a way to make parts!

This forum used to be very active while the ormerod was in production, these days not so much. There were a couple of times some user posted about giving away printed parts for ormerod, just wanted the shipping to be covered.

Maybe start a new thread asking if anyone in your area has an ormerod, or any 3D printer so someone can print you a new part. (hopefully that is the issue in your case, I know it was in mine, but not with the original part).

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InventEd
Thanks for the advice. When the filament is driven through by hand it leaves teeth marks from the insert on the filament and is fairly stiff to turn. Is that normal?. If I do need a new part, any idea where I can get one made as Replikeo is closing down so they can't give me any support. Catch 22, until I get the printer finished I don't have a way to make parts!

What country are you in? I'm in the UK, and can print what you need & post to you. Just send me a link to the STLs. Parts will be ABS - tell me what colour you prefer & I'll use that colour if I have it (otherwise you'll get whatever I have!).

For your issue - ensure that you have assembled the extruder correctly. Incorrect assembly is a common cause of extruder issues. It is *very critical* that you have washers in the correct positions otherwise it will be stiff to turn and causes unreliable behaviour at higher extrusion speeds or not working at all, which sounds similar to your symptoms. Also that the bearing is fully seated in the recess in the extruder block. That recess may need to be filed out a bit if you were over-extruding when you printed it, making it too tight to take the bearing properly.

Dave

Thanks. I am in sunny West Sussex on the south coast of the UK. I will check the washers and the fit tonight and see if I can get it working else I will take up dmould's kind offer of building me a part!

I will also work out how I check the motor current I have set.

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InventEd
Thanks. I am in sunny West Sussex on the south coast of the UK.

I'm a few miles East of you in Seaford, so getting the parts to you will be easy.

Dave