Painter1 Posted September 3, 2016 Report Share Posted September 3, 2016 I have about a dozen molds from Delmart that are unpleasantly unique with respect to fastening & alignment. The fastener bolts are pressed in place and there are no permanent alignment dowels in the molds. The molds come with removable 1/4" pins that fit loosely but are adequate as designed. I bought a press to remove the bolts and press in some dowel pins. I am using the Ultra mold pneumatic clamp system (works great) so need to add alignment dowels on these Delmart molds to keep things square. The holes are there in every corner and are uniform at .002" over 1/4". I can order dowel pins from McMaster but not in a size .003" over. Would it work to use the .002 over pins with LocTite? I really don't want to try and fab these from dowel stock. Any other solutions are welcome. Quote Link to comment Share on other sites More sharing options...
CNC Molds N Stuff Posted September 4, 2016 Report Share Posted September 4, 2016 Some shim stock might work. Quote Link to comment Share on other sites More sharing options...
Baitjunkys Posted September 4, 2016 Report Share Posted September 4, 2016 (edited) Gouge the setting hole a bit. Red loctite. Ive done it to several del molds. With the .002 pins from mcmaster that is. Edited September 4, 2016 by Baitjunkys 1 Quote Link to comment Share on other sites More sharing options...
CNC Molds N Stuff Posted September 4, 2016 Report Share Posted September 4, 2016 Another option is to knurl the pins. Quote Link to comment Share on other sites More sharing options...
Baitjunkys Posted September 4, 2016 Report Share Posted September 4, 2016 If the diy guy has the tools to knurl it would work out great. Quote Link to comment Share on other sites More sharing options...
curt k Posted September 4, 2016 Report Share Posted September 4, 2016 (edited) travers tool sells pin gages cheap (class z) . You could chop one into at least two pieces which would probably be cheaper than buying a hardened dowel pin http://www.travers.com/search.aspx?keyword=pin+gage . Edited September 4, 2016 by curt k Quote Link to comment Share on other sites More sharing options...
Baitjunkys Posted September 4, 2016 Report Share Posted September 4, 2016 The holes are the same size in both halves. The .002 pins work well be it knurled or gouging the set hole. A press fit pin wont work without reeming the recieving hole. Quote Link to comment Share on other sites More sharing options...
Painter1 Posted September 4, 2016 Author Report Share Posted September 4, 2016 First thing - thank you for the help. Could you explain or point me toward some information about gouging & knurling. This is definitely an amateur DIY operation. Quote Link to comment Share on other sites More sharing options...
Baitjunkys Posted September 4, 2016 Report Share Posted September 4, 2016 Sharp object, scratch the inside of the hole a bit to induce interference. Dont smooth it out you want it to be burred up. Red loc tite let set overnight. Quote Link to comment Share on other sites More sharing options...
CNC Molds N Stuff Posted September 5, 2016 Report Share Posted September 5, 2016 Or if you are sure then use Loctite Bearing and Sleeve locker. It will take more heat and is actually intended to lock an interference fit. It used to be the green, but I haven't seen it in on the shelves in a while. I do recall one of the other brands had a green locker that was NOT for bearings and sleeves. Quote Link to comment Share on other sites More sharing options...
CNC Molds N Stuff Posted September 5, 2016 Report Share Posted September 5, 2016 I had to go look it up. Either they have changed the name or I just mis-remembered, but they use the description "sleeve retainer" on most of them now. Most of the Loctite retainers are green. 620 and 640 are rated for high (upto 400F) temperature. 620 is for loose fitting parts. Quote Link to comment Share on other sites More sharing options...
Frank Posted September 5, 2016 Report Share Posted September 5, 2016 Brass shim stock will work with standard pins. Just cut a piece into a strip put it in the hole and tap the pin in. Over time they will loosen but just put another piece in and go again. This way the two pieces will fit easily back together. Buy some pins and I could send you some of the brass. Pm me your address. 1 Quote Link to comment Share on other sites More sharing options...
Painter1 Posted September 11, 2016 Author Report Share Posted September 11, 2016 Update: ordered LocTite Primer, red thread lock and 1/2" pins at .252". About half of the 30 pins stayed, but the other half are loose already and causing problems getting the mold halves apart. Will turn them over to a proffesional machinist. Quote Link to comment Share on other sites More sharing options...
ipt Posted September 13, 2016 Report Share Posted September 13, 2016 i've done it by using the smooth part of a 1/4" bolt (not sure the technical name for that part of the bolt) and hold it in the mold with jb weld. Quote Link to comment Share on other sites More sharing options...
Painter1 Posted September 13, 2016 Author Report Share Posted September 13, 2016 I really appreciate the advice and help received here, related to this issue. It is clear that the failure to make it work is due to my inexperience and lack of skill in the this area. You can lead a horse to water .... Thanks especially to Leonard and Bob. Quote Link to comment Share on other sites More sharing options...
Thebassturd Posted January 19, 2017 Report Share Posted January 19, 2017 You can also toss the sloppy dowels and refit roll pins. easy and works just fine! Quote Link to comment Share on other sites More sharing options...
SlowFISH Posted January 19, 2017 Report Share Posted January 19, 2017 It won't hold forever - but you could even deform the edge of the hole in the mold - put a punch/chisel/etc on the edge - hit it real hard with a hammer - then press the pin in.... sort of like deforming threads on a bolt you want to have locked in place. It works - but if the mold gets real hot and starts expanding - them may loosen up.... this is what happened with me on a lead mold I did this with.... J. Quote Link to comment Share on other sites More sharing options...
mark poulson Posted January 19, 2017 Report Share Posted January 19, 2017 Would JB Weld hold the pins better? Maybe file a flat on two sides, so the Weld would have somewhere to go when the pins are pushed into place. Quote Link to comment Share on other sites More sharing options...
Baitjunkys Posted January 19, 2017 Report Share Posted January 19, 2017 your talking about molds that have identical size holes in both halves dont forget, Roll pins will not allow any clearance in the mating half. Quote Link to comment Share on other sites More sharing options...
Thebassturd Posted January 20, 2017 Report Share Posted January 20, 2017 On 1/19/2017 at 11:40 AM, Baitjunkys said: your talking about molds that have identical size holes in both halves dont forget, Roll pins will not allow any clearance in the mating half. Valid point, you have to slightly OS the mating side holes to allow for clearance. Quote Link to comment Share on other sites More sharing options...
edgecrusher Posted January 20, 2017 Report Share Posted January 20, 2017 Why not get 4 long dowels long enough to go through all molds you want to shoot, slide them in and out as needed, it's not perfect but it will get the job done? 1 Quote Link to comment Share on other sites More sharing options...
DaveMc1 Posted January 21, 2017 Report Share Posted January 21, 2017 5 hours ago, edgecrusher said: Why not get 4 long dowels long enough to go through all molds you want to shoot, slide them in and out as needed, it's not perfect but it will get the job done? They come with 2 like that, it's a royal pain in the butt to have to put the alignment pins back in every time you close the mold. Quote Link to comment Share on other sites More sharing options...
edgecrusher Posted January 21, 2017 Report Share Posted January 21, 2017 (edited) 2 hours ago, DaveMc1 said: They come with 2 like that, it's a royal pain in the butt to have to put the alignment pins back in every time you close the mold. Fully understand.... I run heaps of his molds and agree, I'm thinking along 6 inch dowels, put though 4 or so molds at once, clamp and shoot. Me, I still use his pins and thumb nuts, sure is painfull Edited January 21, 2017 by edgecrusher Quote Link to comment Share on other sites More sharing options...
bryanmc Posted January 22, 2017 Report Share Posted January 22, 2017 On 1/20/2017 at 3:48 PM, edgecrusher said: Why not get 4 long dowels long enough to go through all molds you want to shoot, slide them in and out as needed, it's not perfect but it will get the job done? This is probably the best (and easiest) idea. Quote Link to comment Share on other sites More sharing options...
