H&G die head help please

[sundown57]

I have an H G geometric die head model 102. can anyone tell me how to move the jaws in and out to adjust the size for the rod im trying to thread ?

 

[mmcmdl]

On my 3 heads they have a bolt on the cylindrical side of the head . Not sure about yours , but look for that bolt .

 

[sundown57]

i don't see any thing, plus there is a groove in the part the chaser screws to that runs vertical so im thinking i need a separate set of holders for each size rod

 

[MrWhoopee]

There don't appear to be any chasers (cutting inserts) in that head, do you have them? They are specific for each size and pitch of thread.


FYI, Geometric is a brand of die head which is different from this one.

 

[sundown57]

There don't appear to be any chasers (cutting inserts) in that head, do you have them? They are specific for each size and pitch of thread.
View attachment 421316

FYI, Geometric is a brand of die head which is different from this one.

i do have a set of chasers but can't figure out how to close or set the jaws. Right now there is about a 3/4 inch opening. not good for 1/4-20. appears the jaw rides in an angled groove so there is no way to move it forward or back beyond what the release allwos.

 

[MrWhoopee]

Are they 1/4-20 chasers?

 

[sundown57]

Are they 1/4-20 chasers?

it says 20 on them and i checked them with a thread file. but it doesn't say 7/16-20 or 1/4-20 but either way the opening in the jaws is like 3/4 inch

 

[MrWhoopee]

My experience is limited to Geometric brand heads, but chasers are generally for a specific diameter and the head has a short range of adjustment. I looked on eBay for some chasers for your model head and they specify a particular thread diameter and pitch. It's puzzling that yours only specify pitch, but I suspect there is no way to adjust them down far enough for 1/4-20. Perhaps someone familiar with this style head will chime in. You might edit the thread title to H&G instead of Geo.

 

[mmcmdl]

Yes , as MrWhoopie said above , the chasers are limited to the amount of travel for fine adjustments only . The heads ( some )have a roughing and then a finishing adjustment . Geos look like these below .

 

[benmychree]

On most die heads, the chasers are specific to a size and pitch, and any adjustment for other diameters will distort the pitch, the only one that I know of that does not follow this pattern is the Landis die, which will cut different diameters with a given pitch of chaser, and individual chasers of the same number and pitch may be replaced if badly damaged; these are tangent chasers and may be carefully sharpened on an ordinary bench grinder without regard for chaser length.