Make your own Delrin (aka Big Dog) grips for your CS9/40/45
Hi Folks -
I read a lot of post on this site about these "Big Dog" grips. Like some of you, I tried to contact BIG Dog but no response. So I took it upon myself to see if I can do this. After 2 failed attempts I found the right combination of parts to successfully make these grips for my CS45 (see pics).
If anyone is interested, I attached a PDF file with the parts, tools and steps I used. Sorry - I didn't have time to take step by step pics (which would be after the fact anyway). If you try my instructions, please let me know how you make out. Good luck!
Cheers!
CSFan45
Nice job.
Tell me about using Krylon for a touchup. I've been considering trying it to get a little more grip. Was it the "for plastics" type of Krylon? How does it hold up?
Thanks and thanks for your write-up.
Nice work! I've been working on a pair of 3913TSW grips for my CS9 since I brought it home. I've been doing a little each day, but so far they're coming along nicely.
My goal is to make everything fit around the mag catch and side plate. It's not quite where I want it yet, but it's getting there.
ETA: New picture with the re-contoured mag catch notch.
Last edited by Nakanokalronin; 10-20-2014 at 09:39 AM.
I've read of folks using it their firearms and I can't tell you how it holds up - but I suspect it won't hold up like Cerakote You can always respray it if it wears - only takes a few minutes and suppose to be completely dry in 1 hr. Just don't over spray!
I did another pair of used delrin grips that were really wore and now they look brand new. You can buy it at any automotive store. Best part its cheap for a can and will last a long time.
To Nakano - they are looking really nice!!! The trick is that backstrap - plunger area and how you get the plunger to sit in there. Good luck!
Nice work! I've been working on a pair of 3913TSW grips for my CS9 since I brought it home. I've been doing a little each day, but so far they're coming along nicely.
My goal is to make everything fit around the mag catch and side plate. It's not quite where I want it yet, but it's getting there.
Looking good, Nakanokalronin! Through research and some experience with making these grips, I'm convinced you won't be able to get these on totally straight, they'll always be slightly skewed.
From what I can see from your picture, you are basically there already. I would recommend grinding the mag release button arc a little longer & higher to help it clear the button, then see if that helps to move the grips forward a smidge.
I also took material off of the back vertical wall of the sideplate cutout (top left of the left grip side) to relieve pressure on the sideplate tab. This also helped my grips to slide forward a bit.
Looking at my CS40 with original Big Dog grips, the forward edge of the grips are parallel with the edge of the mag well where it meets the front strap. The cutout for the mag release button is lower than the button (not centered) but it doesn't come near touching the button.
Mine have the extended rear section of the grips so the bottom lines up with the mag bottom. I much prefer this, the extra length makes the grip better - for me.
Looking good, Nakanokalronin! Through research and some experience with making these grips, I'm convinced you won't be able to get these on totally straight, they'll always be slightly skewed.
From what I can see from your picture, you are basically there already. I would recommend grinding the mag release button arc a little longer & higher to help it clear the button, then see if that helps to move the grips forward a smidge.
I also took material off of the back vertical wall of the sideplate cutout (top left of the left grip side) to relieve pressure on the sideplate tab. This also helped my grips to slide forward a bit.
Next comes the fun part - finding the hole!!
I was planning on making the mag catch area on both sides a little bigger for clearance and did so this morning. The grips don't move any farther than in the picture so I may just leave it as is. I ordered a really inexpensive used set of 3913 Hogue grips yesterday so I could modify that insert instead of the one that came with my CS9. This way the CS9 Hogue grips I have stay complete and unaltered.
I have a few ideas to mark and maybe even cut out the hole from the inside. One involves heat and the other is a custom finger operated drill.
Last edited by Nakanokalronin; 10-19-2014 at 10:34 AM.
I think you've figured out the secret to this modification by using the little plastic blocks. This is a great approach to solving the mainspring cup problem.
The little plastic blocks are both a blessing - in that they make it possible - and also a curse in that they are easy to screw up. I went through a bunch of them when I was modifying the Crimson Trace lasergrips to fit various 3d gen models. CT finally wouldn't give me any more and they wouldn't sell them individually. But the good folks at Hogue were happy to sell them to me at a buck a pop (which I was only to happy to pay). Much cheaper than buying spare grips. I might have a few left if you have any problems getting them from Hogue.
I'm sure you figured this out, but there is a ridge inside the Delrin grips that has to fit tight against the rear of the frame. The grips index on the tab under the beaver tail and this ridge and if you don't have it tight the grips will wobble just enough that you'll hate it.
Getting that ridge tight against the frame - and then drilling the hole in the right spot - looks to me to be the toughest part of the project. The CT grips were much easier since I could just put one side on the frame and use that for a template (and it was still tricky).
Last edited by Hill_Country; 10-19-2014 at 08:06 PM.
I was planning on making the mag catch area on both sides a little bigger for clearance and did so this morning. The grips don't move any farther than in the picture so I may just leave it as is. I ordered a really inexpensive used set of 3913 Hogue grips yesterday so I could modify that insert instead of the one that came with my CS9. This way the CS9 Hogue grips I have stay complete and unaltered.
I have a few ideas to mark and maybe even cut out the hole from the inside. One involves heat and the other is a custom finger operated drill.
Looks good with the new mag catch cutout!
Tom 45 shared a good method for finding the pilot hole that has been successful for me, basically a very educated guess with a tiny drill bit. Making sure that the bottom of the grips are straight and flush with the bottom of the frame, I marked the center line of the pin hole first on the frame, perpendicular to the bottom edge, then put the grips on and transferred the mark to the bottom of the grips. I then measured the distance to the approximate center of the grip pin hole from the bottom of the frame on the same line, using a digital caliper. With a 1/16" bit, I drilled a hole the same distance up from the mark on the bottom of the grip, and have been inside the pin hole every time.
@Bruce B,
I have seen some photos of CS40's & CS45's with straight-fitted Delrin grips before, even one example with the extended grip that was fully straight and seated, with the mag button cutout centered and the sideplate apparently fully covered. I believe it is possible to do so with these models, but have yet to find a photo of a CS9 that didn't look to be a bit skewed.
If it is possible, I would love to hear about how someone did so, as I wasted a few grips trying myself.
It might have to do with the types of grips used. The TSW grips may be a tad askew, but still cover the plate while the regular 3913 grips fit straight right off the bat. It could be that the back strap is thicker on the TSW grips towards the bottom due to where the hammer spring cup area is cut off. I'm not 100% sure, but most of the Big Dogs grips I've seen are askew and only a few are straight. This is all speculation since I don't have any factory 3913 grips to compare them to, but mine were more askew until I started taking material off the bottom inside of the back strap past the removal of what's left over of the spring cup retainer.
If you Google "CS9 Big Dog grips" you'll see both examples and the straight one's seem to have been cut all the way across the bottom like what would have to be done with a regular 3913 grip. I can make mine straight, but I have to push them back and up which won't do. As they sit in the picture, they don't move at all and look to be in the same position as the Big Dog versions I've seen.
Thanks for the tip on the hole positioning. After thinking about the other options, I figured that I might as well make a small jig that fits in where the spring cup retainer goes, put the factory pin in and put the grips on. The jig would go up and around the bottom and have a hole on the other side lined up with the one inside. This way I just drill straight through from the outside. I'm waiting on the Hogue 3913 grips to come in so I have time to make one on my milling machine. If it works I'll send the jig to the next person doing the same grip modification and they can send it to someone else, etc.
Last edited by Nakanokalronin; 10-20-2014 at 03:40 PM.
This is a photo of my CS9.
This is the best I could do to get the side plate and mag release centered.
Don't ask me how I did it.
This is the second grip I did...
I really took my time on it.
Wow, great fit on your grips Tom 45!! Your front edge looks parallel to the frame to me, and I've never seen a better fit on a CS9. Thanks for sharing that man, I wish you knew exactly how you did it.
Now that I see it's possible, I think I'll try making a new set for mine as well and see if I can't fit them better. I've still got a few extra grips and won't be using my CS9 during the Winter, so good time for a project!
Looks pretty good to me. I'll try to get mine a little straighter after I get the hammer spring cup insert in. It might have more to do with aligning them better.
This is a photo of my CS9.
This is the best I could do to get the side plate and mag release centered.
Don't ask me how I did it.
This is the second grip I did...
I really took my time on it.
Well done! That's how grips should fit !
I tried to get some shots of the real Big dog grips on my two-tone CS40, it's tough to get any contrast between the grips and the black frame.
I sold my custom CS9D in 2013 and don't come on this side of the forum much but thought I could add some insight to making your own delrin grips.
I did my own and my suggestion is don't make the final cut on the bottom or drill the mainspring hole till you are happy with the grip fit.
I kept messing with mine till I got it up as high as I could. Even though my grip is high on the frame, I could never get the mag release portion of the grip to line up with the frame area. I just opened one side up with the dremel and removed the tabs on the other side by filing them flat with the grip lines.
Unfortunately, most of my images are gone except for one which was my qualification target with the CS9D next to it.
Hope this helps, just keep removing a little on the inside to get it as high as possible till you make the final two mods.
I made a set of grips today for my CS40 using your instructions and they worked well. However, my Dremel skills came up a little short. The grip bottom cut off is not perfect. My only other issue is a little movement, front to back, near the top of grips. Any idea what caused this and any suggestions for a fix? Also, any suggestions for filling the hole on the bottom by the main spring retainer? BTW, the people at Houge were kind enough to send me a new mainspring retainer at no charge.
Maybe this will give you some ideas. I used to modify CT laser grips to fit 3d gens. The construction is a little different, but the principals are the same.
First, the fit at the top under the beaver tail is critical so make sure you have a good fit there. The CT's index along the back edge of the frame and if you don't have a good fit there you'll have trouble. I don't know if the Delrin grips are the same, but there is something that keeps them from moving around. If you have installed the mainspring cup that may be part of the problem if it is keeping the grip from seating properly against the rear edge of the frame. The mainspring cup does not need to be attached to the grip, it will sit in the fingers on the frame with no problem.
As for filling the hole on the bottom, I used black RTV from the auto parts store. An easy way to do it is to wrap the frame very tightly with a single layer of Saran Wrap then install the grip and squirt RTV in the area you want to fill. It needs to cure for several days then the Saran Wrap can very gently be removed. The RTV can be trimmed easily with an Xacto knife. You can also use two part epoxy with a little bone black mixed in for color, but you'll need tiny Dremmel bits to trim it.
Thanks for the info. The Delrin grip fits pretty good but it moves at the top less than a 1/4 inch. I'm thinking about putting some type of glue under it. I like the idea of using the RTV. I'll do that when I get everything else right.
Thanks for the info. The Delrin grip fits pretty good but it moves at the top less than a 1/4 inch. I'm thinking about putting some type of glue under it. I like the idea of using the RTV. I'll do that when I get everything else right.
If it moves at the top - even a fraction of an inch - the grip is not properly hooked under the beaver tail.
I just went down to my shop and looked at an unmodified Delrin grip - there is a shallow ridge <1/16" that has to be flat against the back of the frame. This seems to be missing on a Big Dog grip I looked at and I suspect it was removed on purpose so the lower part of the grip can index against the fingers that support the mainspring cup.
There are also a couple of ears on the inside of the grip that keep the front edge of the grip tight against the frame, but the grip indexes against the back. There is no doubt when it is secured properly. I'd tinker with the fit before I glued anything in place.
CS45Fan & all the others
Thanks for all the pic's and info, nice work! Just picked up a CS40 and am going to give this grip thing a try. Then it's on to the 10MM conversion, maybe!
T&B
I'll check the beaver tail area. That sounds reasonable. Could be my grip is mounted a little bit low and the beaver tail part is not engaging. I know that I didn't remove anything from that area. I was only kidding about the glue...sort of! Ha! I'll post again when/if I get it to stop moving. i may have to get another grip and start over!
Hill Country you were right about the grip not being where it should be under the beaver tail. It needs to go slam up as far as possible. Of course, I can't move it any farther up due to the pin holes already drilled. Not enough length on the bottom to redrill. I was able to put a tight little shim between the grip and the beaver tail and that stopped the movement. Doesn't seem to obstruct any of the works but I haven't fired it yet. I guess I'll get another grip and try to get it just right. Again, thanks for your input on finding the problem. Oh, I really like the feel of the Delrin grips vs the factory Hogue grips.
If it makes you feel any better, every time I modified a new model for CT grips I screwed one up.
Before you write off that grip, you might try a dap of epoxy in the hole and redrill it. Mix in a pinch of boneblack (from Brownells) and it will even match the color. At the very least, you may be able to use the repaired grip to fabricate a jig to locate the hole. Drilling that hole is the most difficult part of the modification.
Refilling the holes with epoxy is a good idea! I really don't want to start another set of grips. If my little shim holds up after firing I may just leave it as is. That Dremel tool is a wonderful device but with a cutting wheel it is very unforgiving! Have a great summer!
I found a grip on Numrich that worked very well on my CS40. Even has the extended rear so it is flush with the bottom of magazine. You have to do the mods like any other grip like in the instructions from above. Mine fit very well with edge parallel with the front strap and correct at the mag release button. The grip is for 4513TSW, 4553TSW part # 762280. Hardest part is drilling the pin holes in the right place..
If you are using the grip I recommend above you will be marking off about 5/16 to 3/4 of an inch
Should that second dimension possibly be 3/8 of an inch?
Not being critical, it just seems to me like 5/16 to 3/4 of and inch is a big tolerance (7/16") - whereas 5/16 to 3/8 seems a much more reasonable tolerance (1/16").
Make your own Delrin (aka Big Dog) grips for your CS9/40/45
So I took it upon myself to see if I can do this. After 2 failed attempts I found the right combination of parts to successfully make these grips for my CS45 (see pics). 
Linear Mode
