Router clamp issue- again! unbelievable

[pshupe]

Ok - this is going to be a bit of a rant. I cannot believe that this plastic router clamp design made it into production. I've had my CNC Shark Pro Plus HD for a few years now. I do not use it a ton but have been using it with a Bosch 1617 router. Now I haven't been able to use it with my dust collector, even though I did pay extra $$$ for the dust boot. The clamp was so poor that it wouldn't hold the router high enough to make the dust boot even somewhat useful. The Bosch 1617 router has a tapered motor that I had resting against the clamp. This guaranteed that it didn't slip down. The problem with that is that the router bit is so far below the dustboot that the dust collector is useless, as I have said previously. So I haven't been using it. Last week I was cutting a guitar top as a test carve in some MDF. The dust was so bad that it got into my router and the router stopped working. I ordered a new router and decided to use my dust collection system. I set my router up about 2 1/2" from where it was resting on the tapered portion and tightened the clamping screw almost to the point that I thought I would either break the clamp, or break the bolt. Then I tighted the 4 bolts that held down the clamp. I even marked a sharpie line around where it was located so I could see if it moved. I'm working on a guitar body for a friend. So I have an expensive mahogany body blank, and a book matched figured maple top. I cut all my channels in the mahogany for wiring, and routed for switch and control cavities as well as control cavity covers. Then I glued my maple top on and put it in my fixture to carve the top. I started my roughing pass and thought it seemed to be cutting a little deep about halfway through the pass. I checked the line and the router had dropped about 3/8". I am completely disgusted. I just turned everything off and left the shop. I don't even want to think about it. This has cost me my maple top and now I have to thickness plane away the ruined top and start over. I just cannot believe this.

Does anyone use the this clamp with this design flaw? I find it extremely hard to believe it to be of any use whatsoever, unless you want to wreck your tools by exposing them to all the dust that this thing kicks up. Funny thing is I just ordered the aluminum clamp from Dixie billet but after burning out a router, I thought I could atleast get a few days with this USELESS clamp. I guess not. Unbelievable!! Have I said that before???

Have they changed this system on newer machines? Thanks for listening. I have to go punch something now!

Regards Peter.

[Eagle55]

Peter,
Hope you feel better after the rant. I know sometimes I feel better when I just stomp around and tell about how bad something is. I'm sure you have known about how bad the clamp was for some time. I know I knew about the problem (and solution... Dixie Billet) for some time before I actually had no choice also. I don't know about the dust being a problem but suspect the MDF (that I don't even allow in my shop if I have a choice) and the glues or adhesive in it may be part of the problem. I cut more corian than I do wood but cut "real" wood when I do. I know I sand a lot of corian and the really fine dust is thick all over which has never been a problem yet. Anyway, all I can say is that I feel your pain and agree that the clamp issue, which has been a know design flaw has been produced for years and as far as I know continues to be. They do a great job to keep the price of the machine down but I still feel that a few tradeoffs such as the router clamp and flexible unlevel table would be good money spent to change the design. I know they have slowly (very slowly) finally gone to a thicker aluminum bed that is more connected and solid. I now they have made some modifications to the clamp but I still think they still hold to the clamp being of sound design. (design is fine... material choice is poor) I kept mine in place until one day I noticed the crack where the ear had completely snapped off. I was lucky that even then the router had not slipped but replaced it as soon as Dixie could get my new clamp to me. Hope things smooth out for you once you get the new clamp in. Just curious, do you know for sure that they dust was what killed the router or do you think the bearings went out. I know I had some experience with the many hours of the 690 series PC router running at 24,000rpm wearing the bearings out, but never have had dust problems that I am aware of, although I have a tremendous amount of it. (no shark dust system in place... just cut and sweep occasionally)

Roger

[pshupe]

Thanks Roger - I am much calmer now. It really is my own fault. There was a reason that I had the router sitting where it was. I guess I was just hoping that over the last 3 years or so relative gravity had changed! LOL Sorry about my rant. I love the Shark for what it is and what it does. Even the software, while somewhat perplexing as far as why it does what it does, is great. I have been very impressed with what I have been able to machine with the shark and vectric software.

I am looking forward to getting my new aluminum clamp and will just move my router down to where it was before and not cut any MDF until I get my new clamp. I would like to get some tips on installing the new clamp so I do not run into any problems. As I have said I am using a Bosch 1617, and now I have 2 of these. I traced the problem to the switch and have a new $8 switch on order. It was definitely the mdf dust. I had a light switch close to the CNC and it was also not working. I blew it out with my compressor and then it worked. Luckily I have tamper proof receptacles. The MDF dust is just so fine and horrible in a number of ways. I really do want to use my dust boot the way it was designed to work. Thanks guys.

Again any tips would be greatly appreciated.

Cheers Peter.

[4DThinker]

Where I work we believe MDF means Mostly Dust, Fine.

[Eagle55]

I don't know that there is anything with the clamp that is all that variable challenging. I can't remember if they have the two front holes slotted to allow for movement or not but mine screwed down in place without any strain or difficulty and held the router like you would think it always should have been. I don't know if the boot plate has any bearing on the install or not. Like I say, I don't use any vac system yet and not sure I plan to soon. I guess if I had the potential problem with the MDF dust I would likely try it. I have heard some stories at some point about the bristles being quit stiff when the shark plunges and the bristles actually push back on the gantry which is quite easily flexed due to the contact with the material being cut until there is lateral movement which sweeps the bristles to the side. I have very little problems with gantry flex because I have found appropriate feed rates that allow the router to cut with little back pressure. Many operators seem to want the magical capabilities and the speed to get things done quicker and begin to see the effects of the gantry flex show up with a vengeance. I'm sure that the boot is a matter of possibly having it right hight enough that it is not always dragging the material but low enough to keep most dust from escaping under it. I suspect that the power of the vacuum is enough to pull it back up even if you have a slight gap under the bristles. However, keep in mind that my experience with the vac has been as an observer on the forum. Also, I know that the hose hook up is important... you want the hose to be supported from above and merely directed by the gantry, not supported and carried by it. Again, the gantry is very subject to flexing which translates to accuracy errors that can ruin projects.

Roger

[NewAgent45]

Peter,
There are lots of posts on this forum discussing your issues. You should read my posts as well as others. I’m attaching links to some of my posts below.
1. Router clamp slipping – Replaced clamp with Sam’s Billet Aluminum clamp.
http://www.cncsharktalk.com/viewtopic.php?f=2&t=3619

2. Dust boot – Upgraded/modified dust boot.
http://www.cncsharktalk.com/viewtopic.php?f=7&t=4066

3. Gantry rigidity – Replaced HDPE gantry support plate with Aluminum plate available from NWA for $99. You could easily make one of these on your own. I choose to by one.
http://www.cncsharktalk.com/viewtopic.php?f=7&t=4264

Hope this helps!

………….. Rod

[pshupe]

Thanks Rod - Yeah I have been looking all over the forum. This started off as a bit of a rant because it really was my own fault. I knew there was a reason I had my router sitting so low in the clamp. Unfortunately I had to ruin a nice people of maple, not to mention having to plane the top from a guitar and joint, thickness, glue up, thickness again, and glue to the mahogany body, just to start from square 1 again to remind me.

I just received Sam's (dixiebillet) clamp yesterday and have it all installed with the dust boot and it seems to work OK. I might adjust the design of the dust boot at some point, as you have done in your thread. Thanks for the link. I think I saw it but didn't read well enough to get the understanding of what you had done. My front brush is a little long, I think, as it gets sucked up into the vacuum hole cutting off some suction. All your mods are great ideas. Thanks again.

The Gantry I was also considering. I want to try and do the simple fixes first. Thanks again for the link. After that I will turn my attention to the table. I think I will make slats from hardwood and bolt to the track, countersink the connections and use the hardwood slats as a spoil board and then I can also use them with the clamps. I think I saw a thread where Sam (dixiebillet) did something similar.

One thing that bothers me is the fact that the machine is sold as having a 7" Z axis but the underside of the Z axis support is barely 6" off the table, also the table isn't square so you have to add a couple of inches of spoil board, bring it down to probably closer to 4", if that.

Thanks for all the tips from the community at large.

Cheers Peter.

[NewAgent45]

Peter.

I'm glad to help! You mentioned working on table improvements. I decided to build a one piece 3/4" MDF spoil board with T-Slots instead of taking apart the machine to beef up the table. I didn't want to take the chance of voiding NWA warranty. I machined the entire piece on the machine. I surfaced the piece on the machine with a 1 1/4 planning bit to true the surface to the machine. During the surface planning step I noticed some stripping of the cuts. This is indication that the spindle is not perfectly perpendicular. In my case on my machine the router mounting leans forward slightly. I cured this by placing pieces of plastic shim stock under the front edge of the router clamp. I believe I ended up with about 0.025 - 030" shim.

After a year of use I just simply cut a new spoil board. I no longer cut through to the spoil board and have made it a practice to use a piece on 1/4" thick MDF mounted between my work piece and the table. I have a collection of different size pieces of 1/4 MDF on hand now.

See the attached link for additional details: http://www.cncsharktalk.com/viewtopic.php?f=7&t=4069

The post listed above is and update to my original: http://www.cncsharktalk.com/viewtopic.p ... ile#p19723

I'm not sure what model Shark you have. Mine is a CNC Shark Pro / Black Diamond. As your post stated the Z range is limited to about 7" total when the gantry is mounted using the upper bolt holes. This is the recommended position. However, the gantry can be mounted using the lower holes which would give you a couple more inches to play with. Of course there would be some additional torque imposed on the gantry of you decide to do this. This may work for you if you keep this in mind and decrease your feed rates a little.

[pshupe]

Thanks - I have the CNC Shark Pro Plus HD. I've had it for a few years and it was up at my father's place which he used it primarily for signs. I'm starting to use it for more guitar building and I need it to be more stable. Eventually I want to get up the nerve to cut fret slots which are 0.023" wide. I purchased a couple of that sized bits from Precise bits.com and also their collet kit for my Bosch 1617 router but haven't had the guts to put those in yet. I might try it after all my stabilizing work is done. I did use a 3/64" bit and it worked really well with no issues at all, but 0.023" is half that size. I will have to test a bit. I can cut the fret slots faster by hand in my mitre saw, so it's not an imperative.

I have the new clamp setup and it is working very very well. Next up will be the aluminum back plate and then a spoil board. I may try a T style spoil board using oak, so I can use my hold down clamps. I hated planing the MDF because of the dust, but I did buy a new dust collector recently and with my new clamp the router is up where it should be for the dust collector to work. There are some great ideas, from some very helpful people, on this forum. Thanks for the info.

Cheers Peter.

[NewAgent45]

Peter,

I'm not sure If you read all the detail in my post. This is a minor thing. When I ordered my Dixiebillet router clamp I asked Sam if he could countersink the bolt holes on the top side. He thought my minor improvement was a good thing too and did it at no additional cost. Per my post ( http://www.cncsharktalk.com/viewtopic.php?f=2&t=3619 ) I replaced the bolts with flathead bolts. This allows the router to sit completely flat on the clamp instead of on the roundhead bolts. If you missed this section of my post you may want to look at the additional details.

We are glad to here you are solving the issues............ Rod