Wades Geared Extruder

How tight is the idler block supposed to be for the Wades Geared Extruder? Is it supposed to be so tight that the spring are completely compressed?

That's probably a bit too tight. You want it tight enough to drive the filament without the hobbed bolt slipping, and you want your E motor tuned low enough to skip steps in case of a jam, rather than strip the filament.

How much the springs are compressed depends on the spring: its length, diameter and wire gauge. If you need to compress them all the way then they are too weak.

---

[www.hydraraptor.blogspot.com]

I use a silicone washer instead of a spring. You can get good tension, but still with a bit of give to allow for filament tolerance. I have never found a good inexpensive source of springs with the appropriate properties, and you need longer bolts with springs.

keep in mind that you also don't want it tight enough to change the shape of feedstock that much. turn down motor current to e axis just enough that instead of slippage your motor does not turn the gear. this allows some sort of pressure control as well.

if your extrude starts to slip your hobbed bolt teeth with become saturated and overloaded quickly, reducing amount of grip the next time it bites feedstock.

Sorry for the late reply guys. I got sidetracked and just now remembered I posted this question. I should have sometime this weekend to play around with it a bit. I have been building my 3D in my spare time, which is rare since the birth of my daughter. I think I bought my kit back in December of 2011 and if I remember correctly there were two different sets of spring. I'll check the other set of springs and see if they are stronger because I can tell you the ones I have install right now springs are completely compressed.

Anyone have a good source for springs?

Certain types of clothes pegs..

I use a couple of zip ties as the axle for the idler block. This keeps the idler block under compression, making it less likely to split, and combined with 2 spring-washer/washer pairs on each of the tensioning screws eliminates the need for tricksy little springses.

You need to work it a bit, and then take out the slack though.

Vik :v)

JRMN Wrote: > Anyone have a good source for springs?

If you do a search (EDIT: ie, google etc) for "small springs" you'll find a variety of mfg and distributor channels that offer a wide variety of coil springs. You can choose the inner and outer diameter, length, compression force, etc. You do not have to defer to Home Depot or Lowes...

An example company is Century Spring

good luck

Edited 1 time(s). Last edit at 02/26/2013 08:46AM by xiando.

thanks

JRMN Wrote:
-------------------------------------------------------
> Sorry for the late reply guys. I got sidetracked
> and just now remembered I posted this question. I
> should have sometime this weekend to play around
> with it a bit. I have been building my 3D in my
> spare time, which is rare since the birth of my
> daughter. I think I bought my kit back in
> December of 2011 and if I remember correctly there
> were two different sets of spring. I'll check the
> other set of springs and see if they are stronger
> because I can tell you the ones I have install
> right now springs are completely compressed.
>
> Anyone have a good source for springs?


As Greg had mentioned, using (small) silicone O-rings is a great solution. You can use 2 or 3 on a bolt for more "give".

The best way to implement this is alternating washer, O-ring, washer, O-ring, washer. This way the O-rings cannot press over each other or slip over the bolt head.

SeeMeCNC's Steve's extruder implements this setup.

Edited 2 time(s). Last edit at 02/27/2013 12:58PM by xclusive585.

I tried a few different springs, but couldn't find anything that worked. I am not looking into the silicone O-rings. I went buy Lowes and Home Depot, but I couldn't find anything. Are you guys talking about the rubber faucet O-Ring?

They have a whole.section of springs at lowes just ask.someone usually at the end of.the hardware section.however the.one set I.found that would work were way too weak and didn't do well for me at all.

Thanks, what about O-rings?

I never see Amazon Supply (www.amazonsupply.com) mentioned in maker-like forums. This was the company formerly known as Small Parts, Inc, which was purchased by Amazon some time ago.

If interested, check out their spring selection in the "Power Transmission" section. It seems the springs come in packs of 10, and most are about US $16-18 for that, so it's pricey but the spring spec filtering is good. Hint: click the "see all springs in this family" link when you get a list of spring types. That's where you can fine tune spring length.

It's been a couple years since I last ordered from Small Parts, but I currently have an order for some springs good for mounting the heated bed. Local hobby and home improvement bigbox stores just don't have parts like this.

Thanks for the tip Brent, but I am looking in the silicone O-ring/washer option because I've had bad luck with springs.